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Zirconia: Taking Dental Restorations to the Next Level

Descripción: Zirconia: Taking Dental Restorations to the Next Level     Since the introduction of porcelain-fused-to-metal (PFM) crowns in the 1960s, the dental industry has sought materials with both the esthetic value of porcelain, and the strength of noble metals to withstand the pressure of posterior occlusal forces.     Glass-ceramic materials that came along in the 1980s were confined to use on anterior teeth. In the early 2000s, researchers found that a toughened version of the metal zirconia met the strength requirements needed for posterior teeth, although the esthetics of the material left much to be desired.     Today, with improved technology, zirconia now rivals PFMs and all-ceramic restorations both for strength and beauty.     A member of the titanium family of metals, zirconia has multi-industry uses and is ideal for use in both anterior and posterior crowns where it fulfills functional requirements and can be custom shaded for quality esthetics.     Advantages     Zirconia is now the preferred material for crown and bridge fabrication, including implant-supported restorations. These are replacing metal-based restoration as the choice of most dentists, lab technicians, and patients. Because it can withstand occlusal forces without causing wear on opposing teeth, the material has quickly replaced full-metal and PFM’s as the material of choice.     Zirconia is more wear resistant than gold, retaining its shape and resisting the tendency to crack and erode by patients who brux. The flex strength value (MPa) of zirconia is more than twice that of traditional lithium disilicate (glass-ceramic) making it the ideal material for posterior crowns and bridges.     Recent Article: Benefits of Digitally Planned Implant Placement     While there is, as always with innovative technology, a learning curve for dentists new to working with zirconia, the techniques for tooth preparations is basically the same as for porcelain and glass ceramic materials. A more conservative preparation of the patient’s original tooth structure is a distinct advantage.     With zirconia, clearance may be as little as 1 mm, while lithium disilicate materials require 1.5 to 2mm and will not be as strong. A thicker chamfer is preferable to a feathered margin to provide for minimum thickness at the margin while retaining the ability to taper it to the prep.     Traditional impressions or digital impressions can be used with equal success.     Concerns     As with all new materials and technology, dental zirconia does have its drawbacks.     Many dentists are hesitant to use zirconia because there are fewer long-term research studies to assess its properties and compare the longevity of the material to gold, porcelain, and lithium disilicate. However, the studies completed thus far all reflect positively on the future of zirconia crowns.     There is also a lack of ability to bond the material to the preps. Though, that might be seen as an advantage by some, since only cement is needed to permanently seat the restoration. The hardness, while certainly considered one of zirconia’s advantages, might be a disadvantage when having to remove or access through them for endodontic treatment.     Recent Article: Why You Should Go Digital With IOS Dentistry     Chairside adjustments, while usually minimal, must be made safely, using diamond burs at slow speed with copious amounts of water, polishing wheels, and cones specifically designed for use with zirconia.     Do not use carbide burs or diamonds at high-speed for adjustments due to microscopic fractures that can occur from the impact of the burs on the material.     Ready to Try?     The future of zirconia use in dentistry is unlimited.     Gold and other noble metals used for decades are slowly dying out due to not only prohibitive cost, but also lack of demand by consumers. Zirconia more than fills that gap.     Researchers continually improve the translucency of these restorations, making them legitimate rivals to all-ceramic for beauty and surpassing other dental materials for strength and durability.     Here are First Choice Dental Lab, we specialize in all types of zirconia restorations, including full-contour and esthetic anterior.     Ship us your case today by clicking HERE, or send digital scans HERE to give zirconia restorations a try!     Want to learn more? Complete the form below and let us help you plan your next restoration!     Pre shaded zirconia has become popular with dental laboratories due to the time-savings and shade consistency the base shade provides. With pre-shaded zirconia there is no need for laboratory technicians to shade each unit in the green stage, saving production time and freeing them up to produce more units. However, standard pre-shaded zirconia systems require the dental laboratory to stock an inventory of 16 shades, each in a large selection of disc thicknesses to cover all unit shades and sizes. Furthermore, you can mill only one shade at a time, thus tying up your mill.     The ArgenZ Anterior Value Shaded Disc System is a collection of pre-shaded super translucent zirconia that covers all 16 shades of the VITA Classic shade guide with just six value-shaded discs. Each disc covers 2-3 shades based on value and chroma, requiring much less inventory and mill time. No green stage shading is required. You simply design, mill, sinter, and stain and glaze.     The discs are as follows: ? Disc 1: Shades A1, B1 ? Disc 2: Shades A2, B2, A3 ? Disc 3: Shades C1, D2 ? Disc 4: Shades C2, D3, D4 ? Disc 5: Shades A3.5, B3, B4 ? Disc 6: Shades A4, C3, C4     Hue and Chroma Shading     Similar to the 16-disc shade systems, each ArgenZ Anterior Value Shade Disc group will be approximately one-half shade lighter than the lightest shade in that group. This makes it easy for the technician to change hue, adjust chroma intensity, and create a good incisal transition zone with external chroma stains.     Value     Traditional all ceramic systems are low in value, especially the light high value shades such as A1. The ArgenZ Anterior Value Shaded System is formulated to deliver a true value to match the guide.     Incisal Translucency and Appearance     The translucency of ArgenZ Anterior and the additional light refraction from the cubic ZR phase results in a natural incisal translucency requiring little to no incisal staining. Units with thicker incisals may require some minor incisal enhancement with incisal enhancement stains.     Stain and glaze system     Many companies make a low fusing fluorescent stain-and-glaze system designed primarily for all-ceramic systems. The most important stains in the kits are the A, B, C, and D chroma stains. These stains are essential to stain up to the next chroma or shade level in each shade group. Incisal stains or intensive blue stains can be customized with black, white, or violet to make any incisal enhancement color needed.     Firing Temperatures     Stains do not penetrate zirconia, so it is not necessary to fire above 800°C. The systems the author uses allow stains to be fired at 750°C (fully melting) and glazes to be fired at 730°C.     Die Shading System     Units must be seated on a die for final staining to match the shade guide. Due to the translucency of anterior zirconia, the final shade is slightly affected by light diffusion and the color of the underlying die and preparation. The anterior unit will appear to have a higher value and slightly more chroma when seated on a die.     Using a die color coating system to match preparation shades (stump shades) is recommended. Preparation coloring systems contain a variety of colors to match light to dark shades. If you do not have guidance on preparation colors (picture or preparation shade), match the die shade color to the prescribed base shade.     Glass Ceramic Materials     Glass ceramic materials have the same chemical compositions as glasses but differ from them in that they are typically 95-98% crystalline by volume, with only a small percentage vitreous. The crystals themselves are generally very small, less than 1μm and most often very uniform in size. Furthermore, due to their crystallinity and network of grain boundaries, they are no longer transparent.     Production of Glass Ceramic Materials     Glass ceramic components are formed using the same processes that are applicable to glass components. To convert them from a vitreous glass material into a crystalline glass ceramic material they must be heat treated or devitrified.     Devitrification can occur spontaneously during cooling or in service, but is most commonly incorporated to produce glass ceramics. It involves heating the formed glass product to a temperature high enough to stimulate crystals to nucleate throughout the glass. The temperature is then increased, which induces growth of the nuclei, crystallising the remaining glass.     Nucleation requires a critical number of atoms converging to form a nucleus. When the nucleus reaches critical size, nucleation occurs. In many glass compositions, nucleation is hampered by the fact the material is silica-based and highly viscous, making it difficult for the required atoms to come together. The crystal compositions can also be complex making nucleation difficult. These factors aid glass forming and cooling without crystallisation.     The devitrification heat treatment must be carefully controlled to ensure the maximum number of nuclei are formed and that these nuclei grow into a uniform fine crystal structure. In order to obtain a high concentration of nuclei throughout the structure, it is common to add a nucleating agent to the glass composition.     How are resin frameworks made? CAD design software is used to design the framework and then it is milled out using milling machines. The resin clasps engage the origin of the undercut rather than the terminal third to allow three to four times the retention of metal. In addition to a superior esthetic color, the resin clasps can be placed more gingival, further increasing its natural appearance.     Acetal dental can also be used for tooth shaded clasps on acrylic partials as well as a single and two tooth posterior unilateral partials. The latter situation is a great way to make an interim partial for a patient having implants placed.     For these reasons, we believe in recommending acetal resin to other dentists and our customers. It’s a strong, versatile material that has proven to be superior to using metal clasps and frameworks. We are committed to researching and finding the best products for our dentists.     Roland DGA Corporation’s three Diamond-Coated Dental Milling Burs, meant to be used with Roland’s DXW-50 zirconia milling machine, are specially engineered for precise performance, maximum durability, and longer life. Extensively tested for tolerances, Roland’s new milling burs are available in three different sizes – 2 mm, 1 mm and 0.8 mm – allowing dental professionals to choose an ideal tool for every milling strategy.     The proprietary design of every Roland Diamond-Coated Dental Milling Bur enables the user to produce up to 10 times the number of units that can be milled with a standard carbide model. Because they are fully compatible with Roland’s existing carbide tools, users can switch to the new tools without any changes in the CAM software, making the upgrade a true “plug-n-play” solution.

Fecha de Publicación: 24-09-21

Cook Your Meat in a Beer Cooler

Descripción:     Cook Your Meat in a Beer Cooler     By this point, there is absolutely no question that the method of cooking foods at precise low-temperatures in vacuum-sealed pouches (commonly referred to as "sous-vide") has revolutionized fine-dining kitchens around the world. There is not a Michelin-starred chef who would part easily with their Polyscience circulators. But the question of when this technique will trickle down to home users—and it certainly is a question of when, and not if—remains to be answered.     The Sous-Vide Supreme, introduced last winter, and of which I am a big fan, is certainly a big step in the right direction. But at $450, for most people, it still remains prohibitively costly. In an effort to help those who'd like to experiment with sous-vide cookery without having to put in the capital, a couple weeks ago I devised a novel solution to the problem: Cook your food in a beer cooler.             "a beer cooler is just as good at keeping hot things hot as it is at keeping cold things cold"             Here's how it works: A beer cooler is designed to keep things cool. It accomplishes this with a two-walled plastic chamber with an air space in between. This airspace acts as an insulator, preventing thermal energy (a.k.a. heat) from the outside from reaching the cold food on the inside. Of course, insulators work both ways. Once you realize that a beer cooler is just as good at keeping hot things hot as it is at keeping cold things cold, then the rest is easy: Fill up your beer cooler with water just a couple degrees higher than the temperature you'd like to cook your food at (to account for temperature loss when you add cold food to it), seal your food in a plastic Ziplock bag*, drop it in, and close your beer cooler until your food is cooked. It's as simple as that.     How to Clean Your Beer Taps     One of the best options for cleaning your beer taps is to use a cleaning kit. A beer tap cleaning kit comes with all the equipment and chemicals you need to clean your system, and they come with easy-to-follow instructions. Instead of cleaning the taps themselves, many bar owners choose to use a cleaning service. Services are quick and convenient, and they ensure that your system is cleaned efficiently and regularly.     How Often Should Beer Lines Be Cleaned?     How regularly you should clean your beer tap system will depend on the volume of your business. High-volume nightclubs, sports bars, and banquet halls should clean their beer tap lines every week or two. Lower volume establishments only need to clean their draft lines every 2 or 3 weeks.     How to Tap a Keg     Beer Keg is an essential skill for bartenders. Here is how you can tap a keg in three easy steps:             Attach the coupler to your gas cylinder. Make sure that you have the correct coupler for the beer you're serving, as using the wrong coupler can affect the gas pressure and how your beer pours.                     Open the gas valve and adjust the gas pressure. Most light beers, ales, and lagers should be dispensed at 10 - 12 PSI. Darker beers like porters and stouts should be dispensed at higher pressure levels, closer to 25 - 30 PSI.                     Take the dust cover off your keg. Attach your beer tap to the keg, ensuring that it is securely locked in place.             Common Problems and Solutions for Beer Tap Systems     Is there an issue with your beer tap system? Most issues with beer tap systems are a result of improper temperature, improper pressure, or cleaning issues. So before you call a technician next time you have an issue with your beer lines, check out this list of common problems and solutions.     How to Choose the Right Draft Beer Tower     There are many reasons one would want to upgrade their draft beer tower on an old kegerator or converted freezer. It might be that the kegerator you bought came with a cheap plastic tower. It may be that the tower you have does not have beer industry standard fittings. It may be that you want to serve something like Guinness? or cold brewed coffee and you need stout faucets to get the restricted flow necessary for that application. Maybe you find yourself filling taller glasses or growlers and need a tower with increased height to accommodate them. Perhaps you are tired of your faucets always being stuck and you're ready to switch to Perlick faucets for their forward-seat design that ensures smooth operation every time. You might just want to make sure that you have 100% stainless steel contact to make sure your system is as sanitary as possible and suitable for serving wine or cider.     Tower Options     Whatever the reason, Beverage Factory has a plethora of draft beer kegerator available with a host of finishes and an assortment of faucet options to choose from. We have basic single faucet towers all the way up to elaborate multi-faucet ceramic towers. We've got customizable T-Style towers that have the same column diameter as a standard kegerator tower, allowing you to easily switch them out with your existing tower.     Generally, switching out your tower is as easy as unscrewing your old tower and screwing in your new one. Something to consider would be how your tower is currently connected. If, for example, you have a 2.5" diameter tower or a tower with a base that screws into the top of your kegerator and you want to replace it with a tower that has a 3" diameter, you will need to drill new screw holes to attach the new tower to the top of your kegerator. The kegerators that we have seen do not have coolant lines in the top of the cabinet so you can be 99% sure you're not going to damage anything by drilling into the top, but if you want to be 100% sure, it's a good idea to call the manufacturer of the model you're working with to ask.     Another thing to consider is how wide the hole in the top of your kegerator is and if it will allow you to drop the beer line through the hole without removing the fittings on the end. If you are upgrading from a single faucet tower to a multi-faucet tower, you may not be able to push all the lines through without detaching one or all of the fittings. You can try pulling the nut back away from the end of the line to push the tube through and then squeezing the nut through afterward, but detaching and re-attaching the fittings may be the only answer. Usually, this just means removing the clamp that holds the beer line onto the hose nipple and then cutting the hose off to release the hose nipple and hex/wing nut that attaches it to your keg coupler. Once they are removed and the lines are pushed through the hole, you can re-attach them with a new clamp. If you are having a hard time getting the hose to slide over the hose nipple, putting the end of the hose in boiling water will make it more pliable. If, for some reason, you find that you cannot reuse the fittings you have removed, we have plenty of new fittings available.     There are a few kegerator brands out there that do not use industry standard parts, so our industry standard fittings may not fit on the non-industry standard coupler that came with your kegerator, but we've got plenty of new keg couplers as well.                             Dispenser Types                             With beer dispenser, the beverages are kept inside the pressurized kegs until you pull the tap lever and pour it. It isn’t magic that pulls the brew through the hoses, it is science. Kegerators dispense the beverages using either CO2 or nitrogen gas.                              CO2 is the most common option for home brewers and beer aficionados. The fermentation process creates a natural level of CO2 when making the beer. Using CO2 to lift the brew to the tap is completely flavorless and preserves the natural carbonation of the beer, helping it maintain freshness in the keg longer. This is closer to the direct-pour taste, right out of the keg.                              Nitrogen dispensers are commonly associated with dark beers, like stout or porters, but also help preserve flavors in other beverages like wine or coffee. They produce smaller bubbles in the drink as it is dispersed and result in a “creamy” effect for some brews. When poured with a slow-pour, stout faucet, it produces a thicker foaming head on the beer.             Beer aficionados, coffee addicts, and wine connoisseurs, consider every detail in pursuit of their passions. How their drinks of choice are served can have an impact on flavor, and some cold beverages just taste better out of a tap. Kegerators keep beverages fresh, perfectly aerated, and always at the ideal serving temperature.     All it takes to experience your favorite on-tap drinks at home is a keg to pour from, the appropriate dispenser set up, and a refrigerator to keep it cool, which is exactly what you get with a beer kegerator. These specifically designed refrigerators not only hold multiple sized kegs of your chosen beverage, they do so at a specific temperature, alongside the tanks that allow it all to be dispensed directly from the keg, with just a pull of a faucet lever. It is the easy, classy way to enjoy your favorite beverage at home.

Fecha de Publicación: 24-09-21

How to Pick A Lawn Mower

Descripción: How to Pick A Lawn Mower     According to the U.S. Environmental Protection Agency (EPA), traditional gasoline lawn mower is a public nuisance to say the least. Using one of them for an hour generates as many volatile organic compounds—dangerous airborne pollutants known to exacerbate human respiratory and cardiovascular problems—as driving a typical car for 350 miles. The EPA estimates that, with some 54 million Americans mowing their lawns on a weekly basis, gas lawn mower emissions account for as much as five percent of the nation’s total air pollution. Beyond that, homeowners spill some 17 million gallons of gasoline every year just refueling their lawn mowers.     So what’s a green-minded property owner to do about keeping the grass down? Go electric, of course!     Electric mowers, which either plug into a wall outlet via a long cord or run on batteries charged up from the grid, create no exhaust emissions and run much cleaner than their gas-powered counterparts. They also need less maintenance, with no spark plugs or belts to worry about, and are easier to use, as they tend to be smaller and come with push-button starters. The icing on the cake might be the fact that electric mowers are cheaper to run, using about as much electricity as an ordinary toaster. Most electric mower owners spend about $5 a year on electricity to keep their grass trimmed just right. The non-profit Electric Power Research Institute reports that replacing half of the 1.3 million or so gas mowers in the U.S. with electric models would save the equivalent amount of emissions of taking two million cars off the road.     But going electric has some minor trade-offs. Electric mowers tend to cost up to $150 more than their gas-powered counterparts, and the plug-in varieties can only go 100 feet from the closest outlet without an extension cord. And the cordless models last only 30-60 minutes on a charge, depending on battery size and type, though that’s plenty sufficient for the average lawn (just remember to re-charge it in time for the next mow).     And, of course, just because electric mowers don’t consume fossil fuels or spew emissions directly doesn’t mean they are totally green-friendly. Most people derive their household electricity from coal-fired power plants, the dirtiest of all energy sources. Of course, running an electric mower on electricity generated from clean and renewable sources (solar, wind or hydro power) would be the greenest of all possibilities, and those days may be upon us soon.             In the market for a new lawn mower, but not sure which type is best? Let us help you navigate the debate on electric vs. gas lawn mowers.             With more lawn mower models on the market than ever before, and so many sizes, styles and features to consider, making the best choice isn’t as simple as it once was. And now, electric mowers are making a big splash in the lawn care industry.         Not long ago, mower motors required too much juice for a cord or batteries to be practical. Not anymore. Modern refinements and innovations allowed corded and battery-powered electric mowers, such as twin-battery mower, to burst onto the scene with gusto.         Gas-burning mowers ignite a mixture of air and fuel, compressing it in a cylinder, then igniting it with a spark to create a miniature explosion which is harnessed to power the machine. Electric mower motors, however, feature magnets interacting with electromagnets, energizing metal coils to move rotors and create power. Electric mowers can be powered by batteries or a 120-volt receptacle via extension cord.     Motor Power     Lawn mower manufacturers can be disingenuous about the real world power levels of their products. It’s not uncommon for electric mowers, for example, to have their “max torque” specs touted as evidence they match gas-burning models in power output. This is deceptive.     Max torque gives an inflated perspective of a mower’s true power because it measures engine torque under little or no load. The fact is, horsepower is the only reasonable unit of measure for lawn mowers, which I suspect is why electric mower manufacturers don’t share this figure. The real-world horsepower of most electric mowers is half, or less than half, the horsepower of a similarly sized gas-powered machine.     Run Time     It’s hard to measure exactly how much run time you’ll get from a tank of gas in your average fuel-burning mower, because much depends on the speed you run it and the density of the grass you’re cutting. It’s a safe bet, though, that a tank of gas will last longer than a fully charged battery on any equivalent electric model.     Most electric mower manufacturers give a maximum run time estimate, which for push and self-propelled mowers is almost always an hour or less. Riding electric mowers might run two hours, tops, on a single charge. Plug-in mowers don’t require batteries and will keep running continuously unless there’s a power outage. In that case, a generator with sufficient voltage capacity can keep you going.     The Environment and Noise     While power and run time certainly favor gas-powered mowers, noise and environmental considerations support electric. Battery-powered mowers have zero carbon emissions, so running one won’t contribute to climate change.     Noise is also a factor worth considering. Many municipalities regulate the acceptable amount of yard noise. Big, beefy gas-powered mowers can easily exceed these guidelines, but battery-powered mowers almost certainly won’t.     Note: Some users find vibration is more severe and bothersome with gas burning mowers than electric.     Operating and Maintenance Costs     Although it’s tempting to believe battery-powered mowers will always cost less than gas-burning mowers long-term, this isn’t necessarily the case. Although you’ll almost certainly spend less on electricity charging your batteries or running your corded mower then on gas and oil for your fuel-burning machine, there’s more to the equation.     Lithium ion batteries don’t last forever and eventually need replacement. They’re not cheap, either. If your electric mower comes with a generous warranty, you might be lucky enough to get a replacement battery (or batteries, if your mower takes two) for free when yours bites the dust. Otherwise, you could be looking at a $200 to $400 expense.     Ease of Use     Robotic lawn mower is usually simpler to use and maintain than their gas-powered counterparts. They don’t need gas, oil changes or new air filters, and you don’t have to make sure the carburetor and spark plugs are clean and functional.     Electric Lawn Mower Pros                     Much quieter;                     Lower maintenance (no fueling, oil changes, belt replacements, air filter changes, etc.);                     Zero carbon emissions;                     Lighter weight (matters for push mowers you need to lift and store).     Electric Lawn Mower Cons                     Battery power only lasts a couple hours (and often less) before requiring charging;                     Corded models can only be used near a power source, unless you have an extremely long extension cord;                     Extension cords are troublesome to lay out and roll up again for storage;                     Often have much less power than most equivalent gas-burning models;             Replacement batteries are often expensive.             Gas Lawn Mower Pros                     Generally much more powerful than electric mowers;             Don’t require cords or batteries;             Often built tougher;             Replacement parts are often less expensive than those for electric mowers.     Gas Lawn Mower Cons                     Considerably louder than electric mowers;             More costly to run (unless you need to replace a battery outside the warranty period);             Require more maintenance (oil changes, fuel preservative added during off-season, etc.);             Generate carbon emissions.     How To Choose the Right Mower     Battery-powered mowers work best for people with small lots who want to minimize maintenance, noise and carbon emissions. But if noise and exhaust don’t bother you, and you just want to mow and be done with it as quickly as possible, you’re probably better off using gasoline engine.     Whether you go with gas or electric, it’s important to choose the right model for your needs. If you’ve got an acre or less to mow, a self-propelled walk-behind mower is probably your best bet. If you’ve got a larger lawn or simply don’t like walking and mowing at the same time, a riding mower will make your life much easier.     More detailed considerations like engine power, blade speed, deck width, regular range and other features come down to personal preference and available budget.     Cordless Lawn Mowers have taken over the lawn and garden section in many retail stores. Six years ago, Tool Box Buzz ran a Best Cordless Lawn Mower Head-to-Head test of five cordless mowers, so we were really interested in how the field of manufacturers has increased and how the offerings have changed after six years.     Our 2020 cordless lawn mower head-to-head will answer the question of whether cordless mowers’ performance “cut it” when compared to a gas-powered mower.     Why Cordless Lawn Mowers?     Even when operated correctly, gas-powered mowers require lots of service including oil changes, fuel filters, spark plugs, and air filters. Oftentimes people wait to do service until the mower won’t start! Anyone who has had to get a small engine repaired knows the hassle and time-sink that can be. Cordless mowers eliminate all of the above-mentioned maintenance, last-minute fuel purchases and they’re quieter to operate and do not emit fumes.     Landscaping on wheels. Thats what lawn and garden tractors provide. If you're serious about having a professional looking lawn, then you need to move beyond a simple mower. At this level, mowing becomes just one task out of many that you need to perform. Enter the lawn tractor, a heavy-duty machine that lets you handle whatever curveballs your lawn throws your way, from dethatching, to aerating, to snow plowing. Keep reading to learn about the different types of lawn tractors and how to pick one.     How to Choose a Lawn Tractor     When deciding what kind of lawn tractor is best for your yard, you should consider what you'll be using it for. If you just need it for some light mowing on a small yard, then a standard lawn tractor will work fine. However, if you want to use heavier attachments for aerating, dethatching, or even tilling, then you'll need a heavy-duty garden tractor.     Two important factors to consider when shopping for the perfect lawn tractor are the grade and the deck size of the tractor.     1. Select a Grade     Lawn tractors can be grouped into the following grades:     Standard Lawn Tractors     Standard lawn tractors provide great power and versatility. They have twin cylinder engines for low-end torque and are a must if you intend to mow large areas or use any attachments on a regular basis.     Some tasks that  lawn tractors can perform with the proper attachements include aerating, dethatching, spraying, spreading, and even snow plowing during winter.     Lawn tractors are designed with hydrostatic transmissions, which offer simple speed adjustments while driving. There are two hydrostatic transmission options: lever or pedal-operated. The pedal-operated option provides the most comfort and flexibility in speed.     Garden Tractors     Garden tractor is lawn tractors on steroids, capable of everything lawn tractors can do plus tilling, furrowing, towing heavier cart loads, and more. Their rugged decks, anti-scalp wheels, and powerful engines enable them to slash through tough brush.     They also include forged or cast iron axles, which are stronger and a good indicator of overall quality level. Finally, their larger back tires provide extra ground clearance and enhanced stability on slopes and inclines. However, if you're dealing with slopes greater than 15%, you should consider a tractor with a traction control system or locking rear differential.

Fecha de Publicación: 24-09-21

Solar Water Pumps: Things To Know andTips For Use

Descripción: Solar Water Pumps: Things To Know andTips For Use     Mechanical pumps have a lot of uses nowadays. They are common in pumping water from wells, aquarium filtering, pond filtering and aeration. When it comes to water pumps, the main use of this device is the exchange of fluids such as water.     From agriculture to the energy industry, pumps are found in a wide range of applications. The main working principle of a water pump basically depends upon the positive displacement principle and kinetic energy which helps pushing the water.     Solar water pumps are a relatively new concept in mechanics. A solar water pump system is commonly seen in residential and commercial uses, as well as for irrigation of agricultural land. Through solar panels, the pump can eliminate the cost of energy and provide a more feasible option that uses energy from the sun (and not fuel-burning mechanisms) for pumping water.     Introducing solar-powered irrigation for poor and remote areas     In times when the entire world is switching to solar, using the sun’s energy in water pumping systems can significantly help and accelerate the development of agriculture in African countries and many other poor remote areas. This concept is known as solar-powered irrigation and is used in many regions nowadays.     The truth is, solar energy might be the easiest way for farmers to produce energy, especially for those living off the electricity grids with poor infrastructure around their homes. Therefore, the use of solar water pump in agriculture is becoming increasingly popular. The concept of solar irrigation represents a virtuous circle—when the sun shines, it feeds the irrigation system and feeds the crops which are dependant on water in sunny weather. Therefore, a large quantity of energy is being released right at the time when it is needed the most.     Solar irrigation is a concept that works through solar water pumps. Below, we are describing them in detail.     What is a solar water pump and what are the most popular types?     As we discussed before, solar pumps present a clean, simple and energy-efficient alternative to traditional electric and fuel-driven pump sets. They are part of an environmentally friendly approach in agriculture and can be used to exploit every region, whether its developed or poor.     Due to their immense potential for productive use and agricultural productivity, solar water pumps are now powering more and more agriculture projects. Knowing that 40% of the global population relies on agriculture as its main source of income, access to water remains an ongoing struggle for many people. This is what solar aims to change and introduce a cost-effective future for around 500 million small-scale farmers all around the world.     The main components in a solar pumping system include a photovoltaic (PV) array, an electric motor and a pump. Solar water pumping systems, on the other hand, are classified as either direct current (DC) or alternating current (AC) systems based on their motor’s ability. Recently, the concept of brushless DC (BLDC) motors for solar pumping water applications was presented as well.     Classification and types of solar pumps     When it comes to stand-alone solar pumping systems, the main types include rotating and positive displacement pumps or hybrid solar pump. Centrifugal pumps are the common choice for rotation and are designed for fixed head applications. Their output increases in proportion to their speed of rotation.     Additionally, pumps are also classified as submersible and surface pumps, based on their placement (underwater and above the waterline).     All in all, the main aspect related to the efficiency of a solar water pump is based on three variables including pressure, flow and input power to the pump. Wire-to-water efficiency is the commonly used metric that determines the overall efficiency of a solar water pump (as the ratio between the hydraulic energy that comes out of the pipe and the energy coming over the electrical wires through solar panels).     Why solar-powered water pumps are the ideal way to boost agriculture in remote areas (And Africa)     A solar-powered water pump is a concept that is environmentally-friendly. More importantly, it is a concept that gets rid of any power grids or fossil fuels used to pump water out of the ground. Below, we are listing the advantages and disadvantages of their use.     Advantages of solar water pumps     The first advantage of solar pumps is that they are reliable in regional and remote areas. A perfect example of this is Africa, which is one of the poorest remote regions in the world with an abundance of water—but also the most dominant region when it comes to most days of sun in the year. On the flip side, Africa is thought to possess 9% of the world’s freshwater resources which translates to around 4,000 km3 of water per year. Deploying solar water pumps in Africa is, therefore, the perfect alternative to any other fuel-based sources—and an alternative which can stimulate life in every part of this continent.     What Is the DC Submersible Pump?     The DC submersible pump as well as other types of submersible pumps look like a metal tube and their goal is to push the water to the surface. This type of pipe-look water pumps conceals the motor within the tube so that the liquid outside the pump does not get access to the electrical parts inside the pump.     The DC submersible pumps are versatile and can better accommodate with different working environments because they can be powered from a variety of independent DC power sources. The most common power sources for the DC submersible pumps are the solar modules, batteries, or generators. The DC submersible pumps with solar power supplies sometimes have a controller in order to enhance the current when the sunlight is low.     More Information on the Power Supply     Typically, the DC submersible pumps can operate on multiple volts of DC power such as 6V, 12V, 24V or 32V. There are some advantages of applying the direct current instead of the alternating current (AC). The first advantage is that the DC power system allows the submersible pumps to adapt to more power supply options such as batteries. It makes the machines portable and is more convenient to apply.     Also, the AC power system needs a controller to control the speed while the AC power system does not need such device. In most cases, the controller of the power system is only needed when the solar power modules are applied.     The DC submersible pumps are more energy efficient too; it takes less power to run a DC submersible pump than an Ac Dc submersible pump. However, there are limits to the DC machines as well. The DC submersible pumps have a shorter lifespan than the AC counterparts. Besides, though the DC machines are more energy efficient and easier to operate without a current controller, they tend to work in a rather lower speed and they are less powerful in pumping.     The Application of Submersible Pumps     The submersible pumps are applicable in multiple areas. For example, they can be used to pump sewage from the septic tanks and it is convenient because the pump deliver the sewage directly to tanks so that they can be transferred to treatment facilities and handled later on.     Secondly, they can be used both industrially and in buildings. Wherever there is too much unwanted water in a work site or when the basement of a building is flooded, the submersible pump can be applied to extract all the water out of the place easily.     The other common use of a submersible pump is for the oil wells. Whether it is an inland oil well or an offshore oil well, the submersible pump can pump out the oil from the ground and transfer it to the factory for further process. Some types of submersible pumps can also be used for drilling wells to a certain depth.     They are called the drilling pumps or borehole pumps. In addition to the industrial use, the submersible pumps can be used agriculturally as a part of the irrigation systems.     What Are the Advantages of a Submersible Pump?     The main goal of asubmersible pumpis to pump out liquids from the ground or from places under the surface level. The submersible pumps are best for job because of several reasons. For one thing, the submersible pump keeps almost all the components within the pipe-like body; therefore, it does not take up much space.     In other words, the submersible pumps can work best in a confined environment comparing to other types of pumps. The submersible pumps connect directly to the storage tanks with pipes or hoses which also take up very limited space as well. As a result, they accommodate with most working environments possible.     The other quality that the submersible pumps have which again comes from the design is that it is the safest options to operate among all other types of water pumps. Since all the working parts of the machine is contained within the body and the whole body will be in the pit of the work site, there is not much of a chance that the user around the machine gets hurt when it is running. This feature alone makes the submersible pumps stand out and become widely accepted.     Once again, because all the components are carried inside the pump body and they operate under the water in most cases, they do not make loud noises. Or to be specific, the noises made while the machine is running are all blocked by the water and the case of the machine. What’s more, the simplicity of the mechanism makes this kind of water pump more effective when it comes to pumping out liquids from underground.     In addition to the safety, the efficiency and the quietness a submersible pump have, the maintenance of the machine is also quite easy. In fact, it does not require much maintenance because the working parts and electrical components are all protected inside the case of the machine, the small contaminants are not likely to enter the body and harm the machine.     Moreover, because the submersible pumps are working in water, they are cooled by the water when running and the machine can last longer with this style of operation.     The application of the DC submersible pumps is mainly in the so called dewatering operations and because of the design and the power supply that they work with, there are a lot of advantages to the use of them.     The primary advantage of a DC submersible water pump is its convenience and ease of operation because the mechanism of the pump is simple and the power system allows more portability to the machine. If the users are looking for a reliable yet compact water pump with multiple power supply options, the Ac Dc screw submersible pump may just be the right choice for them.

Fecha de Publicación: 24-09-21

What's New With Nonwovens in the Medical Industry?

Descripción: What's New With Nonwovens in the Medical Industry?     The utilization of medical nonwoven fabric has outpaced woven materials in recent years. Even when traced back to their rapid adoption during WWII, nonwovens were proven to be superior products in terms of adaptability, disposability, cost, and effectiveness. Manufacturing technology improved in the following decades until current-day use of nonwovens has placed them in a position to dominate the medical textile industry.     What are Nonwovens Fabrics?     Nonwovens are defined as sheets or web structures bonded together by the process of entangling fibers or filaments (and sometimes by perforating films) mechanically, chemically, or thermally. The fibers may be oriented randomly throughout the fabric or only following one direction.     Multiple layers may be combined to achieve the desired elongation, strength, and other mechanical properties. Porosity is controlled by varying fiber density, diameter, orientation, and the use of additional mechanical processing.     Key characteristics of nonwovens that justify their use and popularity:     durability     strength     resilience     dimensional stability     low elongation     specific processing to control porosity     Benefits of Nonwovens Driving this Market     With very deliberate care being taken to lower the incidence of hospital-acquired infection, nonwoven medical textiles are the clear winner in this category, thanks to their unique qualities. Medical textile technology is subject to intense monitoring since human lives are at stake. The intense scrutiny has resulted in better quality products and the development and implementation of innovative new uses in the medical field.     Nonwovens are preferred and poised to dominate the industry because they:     are effective barriers against bacteria     outperform linens for reducing airborne contaminants     can be tailored to changing specifications     help mitigate the risks of today's medical environments due to drug-resistant bacteria, worsening viral threats, polluted indoor and outdoor air, and increases in the numbers of blood-borne diseases     In 2014, nonwovens dominated the global medical textiles market. They accounted for over 55% of global volume, and are projected to gain market share through 2024 consistently.     What is SMS Material?     “SMS” stands for spunbond meltblown spunbond. SMS non woven fabric is a type of nonwoven fabric that combines spunbond and meltblown fabrics.When SMS material is created, it has great water repelling capabilities. This is why manufacturers choose to use SMS material in things like face masks, parts of baby diapers, sanitary napkins, and janitorial coveralls. It’s also used for caps, gowns, beddings, and other hospital accessories.     Why Combine Spunbond with Meltblown?     Spunbond polypropylene is a material that has great durability and strength, no matter if it’s wet or dry. It’s very resistant to fraying and is difficult to unravel, plus it barely absorbs any moisture if it becomes wet.     Meltblown, on the other hand, is softer and more pliable than spun bond polypropylene. Their main advantage is their web strength, which is why they’re usually combined with other nonwoven fibers. While spun bond polypropylene has its advantages, it can feel stiff and uncomfortable when it’s put in everyday applications such as coveralls.Since meltblown has a webbed structure and is softer, when you combine these two nonwoven fibers, it provides the wearer with water resistance while still retaining comfort. It’s also breathable, so even if you’re covered from head to toe (as with coveralls), your comfort won’t be compromised.     Applications for SMS Material     Because of how well SMS material repels water, it’s used in a number of industries where people need to block off fluids or other wet substances. Some areas that utilize SMS material’s benefits used are:             Protective apparel                   Cleanroom coveralls                     Filtration                     Insulation                     Medical healthcare                     Sanitary products             Why The Future Is Nonwoven     Wherever you are sitting or standing right now, there’s bound to be at least one nonwoven fabric in your midst. Teabag or coffee filter, maybe? An air conditioning filter. Lens tissues, bleach wipes, diapers. Surely a face mask or seven.     Though the COVID-19 pandemic certainly pushed awareness of nonwoven fabrics to the forefront, we’ve had our eye on this growing market segment for years. Why? Because pressure-sensitive adhesive tape is often used to make or convert these textiles into usable everyday items.      Here’s our take on how non-wovens will continue to evolve and play a distinct role in the convenience economy.     What Is Non-Woven?     Nonwoven fabrics are the simplest and oldest textile fabrics. Neither woven nor knitted, as the name suggests, non-woven fabrics are broadly defined as sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically.     They are flat or tufted porous sheets that are made directly from separate fibers, molten plastic, or plastic film. They are not made by weaving or knitting and do not require converting the fibers to yarn.     Typically, a certain percentage of recycled fabrics and oil-based materials are used in non-woven fabrics. The percentage of recycled fabrics varies based upon the strength of the material needed for the specific use. In addition, some nonwoven fabrics can be recycled after use, given the proper treatment and facilities. For this reason, some consider non-woven a more ecological fabric for certain applications, especially in fields and industries where disposable or single-use products are important, such as hospitals, schools, nursing homes, and luxury accommodations.     How are Nonwoven Fabrics Made?     Non-woven fabrics are made in two main methods: they are either felted or they are bonded. Felted non-woven fabric is produced by layering thin sheets, then applying heat, moisture, and pressure to compress the fibers into a thick matted cloth that will not ravel or fray.     There are there main methods of manufacturing bonded non-woven fabrics:  Dry Laid, Wet Laid & Direct Spun.     In Dry Laid Non-woven Fabric manufacturing, a web of fibers is laid in a drum and hot air is injected to bond the fibers together.     In Wet-Laid, a web of fibers is mixed with a softening solvent that releases a glue-like substance that bonds the fibers together, and then the web is laid out to dry.     In Direct Spun, the fibers are spun on to a conveyer belt, and glues are sprayed on to the fibers, which are then pressed to bond. (In case of thermoplastic fibers, glue is not required.)     How are Non-Woven Fabrics Being Used?     Nonwoven fabrics penetrate a wide range of markets including medical, apparel, automotive, filtration, construction, geotextiles, and protective. Day by day the use of non-woven fabric is increasing and without them, our present life would be incomprehensible.  Indeed, nonwovens play an integral role in the convenience economy.     Basically there are two types of nonwoven fabric: durable and disposal. Around 60% of nonwoven fabric is durable and the other 40% is disposal.  These specialty fabrics are engineered to provide specific functions such as absorbency, sterility, liquid repellency, resilience, stretch, softness, strength, flame retardancy, cushioning, thermal insulation, acoustic insulation, and filtration. These properties are often combined to create fabrics suited for specific jobs while achieving a good balance between product use-life and cost. There are many kinds of it, such as non-woven fabrics for clothing, non-woven fabrics for packaging, and so on.     Non-woven fabric, is made of oriented or random fibers. It is a new generation of environmentally friendly materials. It is moisture-proof, breathable, flexible, light, non-combustible, easy to decompose, non-toxic and non-irritating, rich in color, and price. Low cost, recyclable, and so on. For example, polypropylene (pp material) pellets are used as raw materials, which are produced by high-temperature melting, spinning, paving, and hot-rolling and continuous one-step process. It is called cloth because it has the appearance and some properties of the cloth.     Therefore, in the non-woven fabric, S, SS,SSS, SMS mean the following: S: spunbonded non-woven fabric = hot-rolled single-layer web; SS: spunbonded nonwoven fabric + spunbonded nonwoven fabric = hot rolled from two layers of web; SSS: spunbonded nonwoven fabric + spunbonded nonwoven fabric + spunbonded nonwoven fabric= hot rolled from three layers of web; SMS: spunbond non-woven fabric + meltblown non-woven fabric + spunbond non-woven fabric = three-layer fiber mesh hot rolled     S and SS non woven fabric are mainly used for furniture, agriculture, hygenic products, and packaging products. And SMS nonwoven fabric is mainly for medical products, like surgical gowns.  We are now exporting these non-woven fabrics to different countries in the world.

Fecha de Publicación: 24-09-21

The Benefits of Stainless Steel Fittings

Descripción: The Benefits of Stainless Steel Fittings     Stainless steel is a versatile material that is used in many different applications. The two most common types of stainless steel are austenitic which is highly corrosion resistant and ferritic which is magnetic.     In this blog we are going to break down the basics of what austenitic stainless steel is, the key benefits it provides and where the uses of stainless steel fittings can be most beneficial.     Stainless Steel     All steels have the same basic iron and carbon composition along with nickel, but stainless steel also contains chromium - the alloy that gives stainless steel its well-known corrosion resistance.     Austenitic stainless steel contains high levels of chromium and nickel and low levels of carbon providing a balance of strength, workability and corrosion resistance. The standard stainless steel alloys used in plumbing applications contains between 18-20% chromium and 8-12% nickel, as well as small amounts of carbon 0.08% and manganese 2%. Austenitic stainless steel has the highest corrosion resistance and are the most commonly used type of stainless steel around the world.     Stainless steel offers a wide range of benefits to the architect and designer of plumbing systems:     Material Benefits     The combining of corrosion resistance with high strength allows the reduction in wall thickness and weight. Stainless steel is resistant to heat and chemical damage. It can withstand very high flow rates - in excess of 40m/s, making it capable to withstand long-term exposure to the elements in almost any environment.     Environmental Benefits     Stainless steel can be used in all types of water, including drinking water in public supply. It has an excellent resistance to the full range of potable waters, including various chloride levels. At the end of its useful life, stainless steel is fully recyclable and retains a higher residual scrap value than ordinary steel.     Economic Benefits     Stainless steel is low maintenance and requires no additional coating, in both indoor and outdoor applications. The expected lifetime of a stainless steel system is more than 50 years, reducing system down time, replacement and maintenance costs over the life of the installation.     Stainless Steel Fitting Applications     With all the benefits that come with stainless steel there are equally just as many applications where stainless steel fitting can be utilized. Here are some key beneficial areas:             Residential & Commercial water systems that are subject to various stresses.                     Commercial & Industrial piping systems that are needing to perform well under the toughest and harshest conditions.             Industrial Projects for sanitary or highly corrosive applications.     WHAT ARE THE BENEFITS OF USING STAINLESS STEEL VALVES?     There are many benefits of using stainless steel valve. There’s no doubt that stainless steel is a great material that is tougher than brass, copper, and cast iron when it comes to tolerating high pressures and temperature. Carbon steel is probably the only material that comes closest to stainless steel. Generally, stainless steel values have various applications due to their great performance in terms of temperature limits, corrosion resistance, and high-pressure tolerance.     APPLICATIONS OF STAINLESS STEEL BALL VALVES     Since stainless steel delivers phenomenally on all fronts, they are used in various industries. Here are a few applications of stainless steel ball valves.     OIL REFINING     Refining crude oil is a long and complicated process that is made much easier through the use of stainless steel ball valves. Crude oil may contain sulfur, carbon dioxide, and many microorganisms, which makes it an extremely corrosive substance. Over time, the constant movement of this substance can break down the metal of the valve. Therefore, you will need pipes and valves that can withstand corrosive crude oil for the longest time. Since stainless steel valves have very high corrosion resistance, they are the obvious choice of use in the oil refinery industry.     MARINE PROJECTS     Certain applications involving pipes and valves occur under or near seawater. Since seawater contains chloride and sodium, it is pretty corrosive to all materials, especially metals. That’s not all, marine environments naturally involve water, a substance that has a substantial impact on all metals.     In such applications, many prefer to use plastic valves since they are more resistant to water and other harsh chemicals compared to most metals. However, the main concern with using plastic valves is that they can’t withstand extreme temperatures and high pressures.     Stainless steel ball valves, on the other hand, have a high-temperature tolerance, are corrosion resistant, and can withstand high pressures. The only thing these valves require is proper maintenance to extend their lifespan under or around seawater.     BREWERIES     Stainless steel ball valves are widely used in breweries. These valves are typically situated on the kettle to help control the flow of liquid during transfers. The reason that stainless steel valves are a top choice in breweries is that during the mashing process, the valve comes into direct contact with a liquid known as wort, which is highly corrosive and can very easily wear down iron valves, and since plastic valves lack the ability to handle high temperatures, stainless steel valves are the best option.     WRAPPING UP     The industries mentioned above are just a few examples of the application that stainless steel valves have. These valves can be used in any process that involves the transfer of a corrosive, high temperature, or high-pressure substance such as gas or liquid.     Stainless steel 304 is one of the most common metals used nowadays. Stainless steel is well known and preferred over several other metals due to its physical properties including good corrosion resistance, durability, high strength, etc. Various types of commercial, industrial, and residential products are created using Stainless Steel. Stainless Steel 304 flanges are one of the most popular meteal products created out of this metal. There is a vast variety of flanges available for purchase. This article discusses eight important types of flanges and their uses.     Types of Stainless Steel Flanges     The following are the top 8 stainless steel flange used in stainless steel pipes:             Weld Neck Flanges: Flange is distinguished by their protruding necks. The weld neck flanges have the same angle and thickness as that of the pipe. Weld Neck Flanges are considered best for use in severe service conditions such as sub-zero or high temperatures and high pressure.             Slip-On Flanges: These are the most affordable range of flanges available for purchase. The slip-on flanges as the name suggests need to be easier to slip them over the pipe and hence they have a slightly larger diameter than the pipe. These stainless steel Slip On flanges are fillet welded to a position and are ideal for low-pressure applications.                     Blind Flanges: The flanges are designed without a bore, and are used to seal vessel openings or piping systems. Blind Flanges are ideal for use where the piping systems or vessels require constant inspection. The blind flanges can be supplied with or without hubs. This SS 304 Blind Flanges can easily handle high stress caused due to internal pressure.                     Threaded Flanges: Threaded Flanges also known as screwed flanges, and have a thread inside the flange bore which fits on the pipe with matching male thread on the pipe. Threaded flanges are used for special applications and can be easily assembled without welding. Stainless steel 304 threaded flanges are compatible with pipes with external threads.                     Lap Joint Flanges: The lap joint flanges are the type of slip-on flanges that are used with stub end fittings. Lap Joint Flanges are ideal for piping systems that require regular inspection and maintenance such as low alloy steel pipes or carbon steel pipes.                     Socket Weld Flanges: The flanges are designed for use on small diameter and high-pressure piping. The socket weld flanges have internal welds which contribute to their durability as well as endurance limit. These flanges are used in the chemical processing industry.                     Orifice Flanges: The function of these steel flanges is to provide access to a line for metering liquids or gases. The orifice flanges are installed with orifice plates or flow nozzles.                     Ring–Type Joint Flanges: These flanges are used for high pressure and temperature applications. The ring-type joint flanges has a specially designed grove that can be easily compressed on blind, slip-on or weld neck flange. The flanges help in avoiding leakages in pipelines where media is transferred at high pressure and high temperature.

Fecha de Publicación: 24-09-21

Nonwovens for Home Textiles

Descripción:   Nonwovens for Home Textiles     Nonwoven fabric is a fabric-like material made from lengthy fibers, bonded together by chemical, mechanical, heat or solvent treatment. In simple terms, they are textiles made from fibers or threads joined together without weaving. Nonwoven materials classically lack strength unless densified or toughened by a backing. In recent years, nonwovens have become an alternative to polyurethane foam. Nowadays nonwoven fabrics are mostly used as home furnishing fabrics. Nonwoven fabrics are described as sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically. They are flat, porous sheets that are made directly from separate fibers or from molten plastic or plastic film. They are not made by weaving or knitting and do not require converting the fibers to yarn. Typically, a certain percentage of recycled fabrics and oil-based materials are used in nonwoven fabrics. The percentage of recycled fabrics varies based upon the strength of material needed for the specific use. Conversely, some nonwoven fabrics can be recycled after use, given the proper treatment and facilities. For this reason, some consider nonwovens a more ecological fabric for certain applications, especially in fields and industries where disposable or single use products are important, such as hospitals, schools, nursing homes and luxury accommodations. Nonwoven fabrics are engineered fabrics that may be a limited life, single-use fabric or a very durable fabric. Nonwoven fabrics provide specific functions such as absorbency, liquid repellence, resilience, stretch, softness, strength, flame retardancy, washability, cushioning, filtering, use as a bacterial barrier and sterility. These properties are often combined to create fabrics suited for specific jobs, while achieving a good balance between product life and cost. They can mimic the appearance, texture and strength of a woven fabric and can be as bulky as the thickest paddings. In combination with other materials they provide a spectrum of products with diverse properties and are used alone or as components of apparel, home furnishings, health care, engineering, industrial and consumer goods. Types of nonwoven fabrics: Nonwovens, depending on the production process can be divided into: ? Materials produced by physicochemical methods; and ? Mechanically produced materials. Materials produced by physicochemical methods Most nonwoven materials, are made by binding fibers with adhesives. The most common glued materials are those based on fibrous cloth (a layer of textile fibers whose weight is 10–1000 gsm and more). The cloth is most often formed mechanically from several layers of combed fibers passing through the dotting drum of a combing machine. Fibrous cloth may be produced by the aerodynamic method in which the fibers are removed from the drum of the combing machine by a stream of air and transferred to a mesh drum (condenser) or a horizontal mesh with a maximum speed of up to 100 m/min, or by water dispersion of the fibers on the mesh of a paper machine. A fibrous cloth is usually made of cotton, a mixture of viscose and polyamide fibers or the waste products of textile manufacture, including unspun fibers. The most common method of producing bonded nonwoven materials are to  impregnate  the cloth with a liquid adhesive or  spraying/printing the adhesive over the surface of the cloth. Gluing the fibers includes saturate bonding and spray bonding or a latex adhesive is applied to the fibers and then the fabric is dried. The impregnated material is dried and treated in chambers heated by hot air or infrared radiation. The nonwoven materials made in this fashion (at a rate of 50 m/min and more) are used as interlacing and sealing materials, as heat and sound insulation materials for upholstery, bedding and drapery liners. Melting fibers together can only be accomplished with synthetic, thermoplastic fibers or with a blend of fibers containing thermoplastic fibers or fusable powders. These methods include thermal bonding (heat applied to the web with or without pressure) a carded web, ther-mobonding a spunlaid web with a calendar, thermobonding a melt blown or flash spun web with a calender, thermal bonding a carded or air laid high loft web in an oven.In the hot-pressing process, the fibers are bonded by thermoplastics such as polyamides, polyethylene, and polyvinyl chloride at pressures of up to 2 mega newtons per sq m (MN/m2), or 20 kilograms-force per sq cm (kgf/cm2), at high temperatures, usually on special calenders. The bonding is preceded by thermal treatment of the fiber layer, which contains an adhesive that is applied to the fibrous cloth during its formation or after its formation. In the spunbonded method, synthetic fibers are formed as they leave the spinnerets of spinning machines and pass through troughs in which they are stretched in an air current; they are then placed on a conveyor belt and form a sheet. The material formed in this way is most often bonded with an adhesive; in some cases the stickiness of the fibers themselves is sufficient.     SPUNBOUND/SPUNLACE     Spunlace nonwoven fabric is produced by depositing extruded, spun filaments onto a collection belt in a uniform random manner followed by bonding the fibres. The fibres are separated during the web laying process by air jets or electrostatic charges. The collecting service is usually perforated to prevent the air stream from deflecting and carrying the fibres in an uncontrolled manner. Bonding imparts strength and integrity to the web by applying heated rolls or hot needles to partially melt the polymer and fuse the fibres together. Since molecular orientation increases the melting point, fibres that are not highly drawn can be used as thermal binding fibres. Polyethelene or random ethylene-propylene copolymers are used as low melting bonding sites.     Spunbound products are employed in carpet backing, geotextiles, and disposable medical/hygiene products, automotive products, civil engineering and packaging products.     The process of Spunbound non-woven production tends to be more economical as the fabric production is combined with the fibre production.     AIRLAID     The process of airlaying is a non-woven web forming process that disperses into a fast moving stream and condenses them onto a moving screen by means of pressure or vacuum.     Airlaid fabrics is mainly composed of woodpulp and has a nature of absorbing well. It can be mixed with a definite proportion of SAP to improve its capabilities of absorbing wet. Airlaid non-woven is also referred to as dry paper non-woven. The nonwoven is made through the airlaying process. Transit the woodpulp into the bundle of airflow to make the fibres disperse and agglomeration on the floating web. Airlaid non-woven is reinforced of web.     Airlaid non-woven products are employed in a number of different products across a wide range of industry’s including; the interlining of clothes, medical and hygiene products, embroidery material and filter material.     DRYLAID     Dry laid webs are mainly produced using staple fibres natural or manmade. Dry laid webs formation mainly consists of 4 steps: Staple fibre preparation –> Opening, cleaning, mixing & blending –> Carding –> Web laying.     Advantages of Drylaid non-woven production include; The isotropic structure of the web, voluminous webs can be produced and a wide variety of process able fibres such as natural, synthetic, glass, steel and carbon.     Drylaid non-woven products are employed by many products ranging from cosmetic wipes and baby diapers to beverage filtration products.     WETLAID     Wetlaid non-woven are non-wovens made by a modified papermaking process. That is, the fibres to be used are suspended in water. A major objective of wet laid nonwoven manufacturing is to produce structures with textile-fabric characteristics, primarily flexibility and strength, at speeds approaching those associate with papermaking.     Specialized paper machines are used to separate the water from the fibres to form a uniform sheet of material, which is then bonded and dried. In the roll good industry 5 -10% of nonwovens are made by using the wet laid technology.     Wetlaid is used for a wide ranging amount of industries and products. Some of the most common products that use wetlaying non-woven technology include; Tea bag paper, Face cloths, Shingling and Synthetic fibre paper.     NON-WOVEN CHARACTERISTICS     The particular set of properties that a printed nonwoven fabric may have is dependent upon the combination of factors in its production. Each different ttype of non-woven will consist of different characteristics.     The range of characteristics include             The appearance of non-woven fabrics may be paper like, felt like, or similar to that of woven fabrics.                     They may have a soft, resilient hand, or they may be hard, stiff or broadly with little pliability.                     They may be as thin as thin tissue paper or many times thicker.                     They may also be translucent or opaque.             Their porosity may range from low tear and burst strength to very high tensile strength.             They may be fabricated by gluing, heat bonding or sewing.                     The drapability of this type of fabrics varies from goof to none at all.             Some fabrics have excellent launderability; others have none. Some may be dry-cleaned.             Non-woven fabric is a material defined as     Sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically.     Non-woven polypropylene fabric is, similarly, a thermoplastic polymer – like polypropylene – but made to look non-woven. One of its major applications is non-woven bags for shopping. Nevertheless, the non-woven fabrics gain more and more popularity in the fashion industry.     With so many plastic bags ban policies sweeping the world in their attempt to reduce plastic pollution, non-woven bags (either for shopping or for fashion) are becoming the norm. But are non-woven bags as eco-friendly as advertised?     Why Are Non-Woven Bags Environmentally Sustainable?     As we all know, the true sustainability of a product or a fabric resides in its recyclability and reusability. Just like canvas shopping bags or jute bags, non-woven carriers are reusable for very long periods. Polypropylene is recyclable, and so are non-woven polypropylene tote bags for shopping or drawstring bags for sports or leisure.     After years of use, you can throw away a broken, non-woven polypropylene office bag uses PP nonwoven fabric, for instance. As long it is collected and appropriately sorted, you can rest assured it will enter the recycling process and give life to a new item.     Non-woven bags for shopping come with plenty of eco-friendly advantages that are not available to plastic bags or natural fibers, for instance:     You can wash them and disinfect them without worrying about their resilience; as long as you wash it in cold water, your washing machine will not take its toll on it;     You can spray your non-woven bags with disinfectants and anti-bacterial substances for enhanced safety, especially during these times of global health concerns;     Both woven and non-woven polypropylene comes from recycled materials (plastic), so it is easy to understand why non-woven shopping bags come with high levels of sustainability. They are products of recycling and make products of recycling in their turn.     Before we move on to the next reason why non-woven bags are the sustainable answer to plastic bags, we have to say that no plastic whatsoever is biodegradable or ecologically friendly.

Fecha de Publicación: 24-09-21

The evolution of plasma cutting

Descripción: The evolution of plasma cutting     Plasma cutting has come a long way since it was first developed in the late 1950s by engineers at Union Carbide Corp. Today it is one of the most widely used metal plate cutting processes for a large variety of industries.     Early plasma cutting systems were used primarily for cutting stainless steel and aluminum plate from 0.5 to more than 6 in. thick. These systems, primitive by today’s design standards, were the most practical method for cutting heavy nonferrous plate. Most were mounted on XY cutting pantograph-style machines that used either photo-cell tracers to duplicate large black line engineering drawings of the parts to be cut, or a magnetic tracer to follow the path of a steel template.     Engineers continuously worked on the process throughout the 1960s with the goal of improving cut quality and the life of the consumable nozzles and electrodes in the cutting torch. Plasma began gaining momentum during this period as the process improved and as users became aware of its ability to cut complex shapes in nonferrous materials at very high speeds.     In 1968 radial water injection was introduced. This patented nozzle technology used pure water injected radially around the plasma jet to constrict the arc, increasing its energy density while improving nozzle cooling and thus allowing faster cut speeds, higher-quality cuts, and the ability to cut carbon steels at speeds four to six times faster than an oxyfuel cutting process.     At about that same time, XY coordinate drive cutting machine technology was being improved. Microprocessor control technology started to become the brains of the XY motion control machines, allowing for better accuracy, higher cutting speeds (necessary for the new-technology plasma systems), and higher levels of automation and productivity on the shop floor.     Through the 1970s plasma cutting technology replaced many oxyfuel-based steel cutting applications from 0.25 to 1 in. thick, while still maintaining its stronghold on the stainless and aluminum markets. While plasma could cut steel thicker than 1 in., the oxyfuel process still was a lower-cost alternative for heavier steel plate.     Timeline of Major Engineering Breakthroughs     With the baseline of plasma’s early history established, let’s take a look at some of the major engineering breakthroughs with this technology:     1957 The plasma cutting process was developed and patented by Union Carbide as an extension of the gas tungsten arc welding (GTAW) process.     1962-1967 Several new developments were completed in consumable design, and the dual flow torch was designed to help improve consumable life and cut quality on nonferrous materials.     1968 The water injection process was commercialized. This process allowed for cutting with clean, square-cut edges and faster speeds, as well as cutting of carbon steels with acceptable cut quality.     1970-1979 The water table and water muffler, designed to provide fume and smoke control, debuted. Automated arc voltage-based height controls for more consistent cut quality and longer consumable parts life emerged.     1980-1984 Oxygen-based plasma cutting systems that helped improve edge squareness and edge metallurgy (softer, weldable edge) and allowed for cutting carbon steels at lower power levels and higher cut speeds (see Figure 2) were introduced.     1984-1990 Many developments in the air plasma cutting process allowed for better portability and lower power levels for hand cutting and mechanized thin-sheet cutting.     1990 Better power supply designs using pulse width-modulated, current-controlled outputs were developed. Some systems started to use lighter-weight, smaller inverter technology power supplies suitable for portable, hand-held plasma systems.     1992 Long-life oxygen process technology was introduced. This was essentially a microprocessor-controlled method of controlling plasma gas ramping pressures as well as power supply output amperage. It helped increase typical oxygen plasma consumable parts life by four to six times; improved parts consistency; and helped lower the cost of plasma cutting.     1993 High-definition plasma, a technique that required the previous long-life oxygen technology to implement, was developed. This process allowed for a new nozzle design that increased the energy density of an oxygen plasma arc by as much as four times, allowing for squarer, cleaner cuts in all material thicknesses.     1996 Automated gas flow control systems emerged. They interfaced digitally with the machines’ CNCs. These gas flow controls eliminated some of the potential for machine operator-related errors in setting parameters for the cutting process.     1996-2006 Many developments occurred relating to improving cut quality and productivity and automating the many process cut parameters. These included integrated plasma, a system that closely coupled the CNC, the plasma power supply, the gas flow control, the CAM software, and the height control system to automate the process. With this expertise built into the system, the machine operator’s job became much simpler, and the process relied less on operator expertise.     Recent Technology Developments     In the last seven years, developments in plasma cutting technology have come at a fast pace. The latest revision on high-definition machines is their full integration with the CNC machines they are coupled with. New CNCs have touchscreen accessibility, minimizing the number of buttons involved in operating a plasma cutting machine and making operation as simple as almost any Windows?-based software. Operator training has been simplified on even the largest, most complex CNC plasma cutting machines.     The operator’s job also has been made easier with improvements in auto-calibrating height control functionality. The operator does not need to make adjustments as the consumable parts in the torch wear out.     Hole cutting has been improved with a large database of information in the CAM software that automatically recognizes CAD features and implements the best possible cut path and plasma cutting parameters, including on-the-fly shield gas changes that nearly eliminate the normal taper found in plasma-cut holes on steel (see Figure 3). This process is transparent to the machine operator and system programmer, eliminating the need for them to be experts.     Improvements in cut-to-cut cycle times have been incorporated into CAM software. The software automatically recognizes areas of a full cutting nest (multiple parts) and modifies the traverse time, torch retract time, and gas preflow time to decrease production times and improve product throughput.     Nesting software now applies the lead-in points in the most effective way to avoid traversing over areas prone to collisions with previously cut parts.     Improved plate beveling software has simplified the integration and operation of a bevel head with XY CNC cutting machines. This advancement, again associated with the system’s CAM software, saves much of the programmer/operator trial-and-error testing that has always been necessary to hold the best tolerances on plate edge beveling applications, such as weld prep.     Very new vented nozzle and gas mixing technology has helped improve stainless steel edge quality. Edges are squarer, shiny, and weldable.     Air plasma cutting systems from the major manufacturers also improved dramatically in terms of cut quality, consumable life, and duty cycles. These systems, primarily designed for portable and in-shop hand-held cutting applications, now are available with quick-change mechanized torches and interface easily to a variety of lower-cost CNC machines. Systems are available from a 30-amp, toaster-sized unit that operates on 120-V household current to sever materials up to 0.5 in. thick, to a 125-amp, 100 percent duty cycle industrial unit that can sever 2.25-in. materials. Both portable systems can be used with a hand torch or can be mechanized for a variety of automated cutting applications.     Industrial mechanized systems typically are 100 percent duty cycle, available with machine torches, and designed to use a variety of compressed gases to fine-tune the cut quality for different materials. These systems are available in various sizes and capacities from 130 to 800 amps.     Many other advances have been made to improve reliability, performance, consumable life, cut quality, and ease of use since the first plasma system was created. The process shares the cutting market with laser cutting, abrasive waterjet, and oxyfuel cutting, all of which deliver accuracy, productivity, and long-term cost-effectiveness when used for the appropriate applications.     What can be considered light duty?                                                                                     A light duty plasma cutting machine can become a need for any workshop, artist, contractor, etc. that so far have been using oxy-fuel and is ready to make the leap to a better solution.                                                                                        Actually, after experiencing a handheld plasma machine, almost nobody wants to return to oxy-fuel.                                                                                   That is because even a light-duty plasma cutting system can make a big difference in efficiency and productivity.                                             So, in this post, we are going to consider what a light-duty plasma cutting system is and which one you should get.                                                                                     But before getting into this amazing topic, let’s consider what plasma cutting is.                                             Most people classify plasma cutting systems in light, medium and heavy-duty. A handheld plasma cutting machine used in a small cutting table can be considered light-duty.                                                                                     In general terms, a medium-size cutting table powered by some plasma cutting machine would be a medium-duty system.                                                                             A mechanized cutting system, which could occupy the heavy-duty slot, can be built in a stronger structure and composed by more than one cutting machine.                                                                           But that classification is not a general rule for plasma cutting manufacturers.                                                                             For the sake of this post, as quoted before, we are considering a handheld or portable plasma cutting machine as a light-duty one.                                                                                 Now, before buying a light-duty plasma system, you may need to know when to use a portable and when to use an automated system. So, let’s consider some of it.                                         What Are The Advantages Of Fiber Laser Cutting Machine     Fiber laser is well received in the market now, because of its outstanding advantages of good beam quality and high conversion efficiency, it is widely loved in some finishing fields. At present, the proportion of fiber laser in the industrial field is close to 50%, which is also a kind of active choice for products in many industrial applications. Compared with traditional gas and solid-state lasers, fiber lasers have great advantages as frequency conversion light sources. In this article, we are going to talk about what is fiber laser cutting machine, what are the features, advantages & benefits of fiber laser cutting machine and applications & uses of fiber laser cutting machine.                                     What Is A Fiber Laser Cutting Machine?                                             Fiber laser cutting machine is a new type of machine in the world, which is used to output high energy density laser beam. The laser beam is concentrated on the surface of the workpiece, so that the area of ultra-fine focus on the workpiece is instantly melted and evaporated, and the spot is moved through the CNC mechanical system. Automatic cutting by illuminating the position. Compared with large volume gas laser and solid-state laser, it has obvious advantages and has gradually become an important choice in high-precision laser processing, lidar system, space technology, laser medicine and other fields.                                                                                     The optical plate fiber laser cutting machine can be used for both plane cutting and oblique cutting, with neat and smooth edges. It is suitable for high precision cutting of metal plate. At the same time, the manipulator can replace the original five axis laser for 3D cutting. Compared with ordinary CO2 laser cutting machine, it saves more space and gas consumption, and has high photoelectric conversion rate. It is a new energy-saving and environmental protection product, and also one of the world’s leading technology products.

Fecha de Publicación: 24-09-21

How we got duped into cooking with gas

Descripción: How we got duped into cooking with gas     Gas stove actually unleash indoor air pollutants like soot, formaldehyde, carbon monoxide, and nitrogen dioxide. Beyond that, greenhouse gas emissions from fossil fuels like natural gas drive climate change. That’s why there’s a push now to electrify homes; electric stoves can run on clean energy.     The history of how “cooking with gas” campaigns have made a source of fossil fuel combustion in our homes seem completely innocuous gets pretty ridiculous. Leber dug up a rap video from 1988 that spends an entire four minutes hyping up gas stoves in rhyme. “Gas is so hot, it’s not on when it’s off / it’s the only way to cook, that’s what I was taught,” the rap starts off.     Fast forward to about two minutes into the video, however, and there’s a disclaimer in the lyrics that my colleague Sean O’Kane noticed: “Safe cooking begins with range location / avoid main traffic paths and also isolation.”     Today, gas groups pay social media influencers to advertise the supposed benefits of cooking with the fossil fuel, Leber reports. A public relations representative even posed as a resident in a neighborhood to stir up backlash against building codes that would discourage natural gas hookups in new construction, she writes.     You have to read the truly bizarre and alarming history of gas that Leber traces in her article. With many of us spending more time working and hanging out at home during the pandemic, it’s more important than ever to be aware of what we’re exposed to inside the place that’s supposed to be our refuge.           How to Deep Clean Your Gas Stove Burners Using Natural Cleaners         No library of kitchen cleaning tips would be complete without an article on deep cleaning gas and electric burners! Dirty, greasy gas burner grates and drip pans not only age the appliance, but they also can affect your cooking and present a fire hazard. Cleaning stove burners is simple when you use these tips from the pros. Read on to see how you can get your stove sparkling clean with gas stove cleaner made from natural ingredients.         How Often To Clean Gas Stove Burners         Tempered glass gas stove is easy to maintain. However, when the flow of gas gets blocked, the burner heads can’t burn efficiently. Check the gas burners for irregular flame patterns and yellow flames. These are the best indicators that it’s time to grab your gas stove cleaner and get to work. Other than that, cleaning your gas stove monthly should keep it working at its best.         Here’s what you’ll need to get your gas burners clean:              Dishwashing detergent             Baking soda             Non-abrasive scrub pad         Cleaning cloths         Old toothbrush             Paper clip             Cleaning Gas Stove Burners and Caps         If you have a cooktop with a pilot light, you’ll need to shut off the gas valve first. Gas burners have a removable ceramic cap that diffuses the flames. Beneath the caps, the burner head sits atop the gas tube. Remove the caps and the burner heads by carefully lifting them straight up. Avoid damaging the ignition electrode if you have one.         Soak the burner heads and caps in soap and warm water for 30 minutes. Scrub buildup from the burner heads and caps using a non-abrasive scrub pad and an old toothbrush. If the port openings are clogged, use a paper clip to clear them. Be careful not to damage the metal.                 How To Clean Electric Stove Burners             Here’s what you’ll need to get your burner stand clean:             Dishwashing detergent             Baking soda             Non-abrasive scrub pad         Microfiber towel             Cleaning cloths                 If your coils and drip pans have caked-on grime, turn the burners on for a few minutes to burn off residue. After they cool, wash the drip pans with warm soapy water and cover them completely with a mixture of 2 parts baking soda and 1 part water. Let the drip pans sit for 15 minutes.               While the drip pans are soaking, wipe down the stove coils with a damp cloth to remove stains and residue. Scrub the drip pans and rinse the baking soda mixture. Use fresh soapy water to wash off the residue, then rinse and dry. Buff them to a nice shiny finish with a microfiber towel. Now, on to your stovetop.                 How to Clean Your Stovetop                For gas stovetops, use caution and avoid getting the electric starter wet. Degrease the stovetop by wiping it down with a damp cloth to loosen up the top layer of residue. Use a sponge and soapy water to cut through the grease and wipe down your stovetop with a damp cloth to remove the cleaning solution.                 For tough buildup, turn to your homemade baking soda mixture. Spread your cleaning paste over the entire stovetop and let it sit for at least 15 minutes. Scrub the stovetop and wipe off the baking soda cleaner with a clean, damp cloth.                 If you are intimidated by cleaning your gas or electric stove, or any other place in your kitchen, don’t fret. Call The Maids for a free estimate and get that good-as-new, clean home feeling you love.                             Gas stove tops offer quick temperature control and are more affordable to use than electric stove tops.                 The best material for a gas stove is one that can conduct and distribute heat evenly, and respond quickly to temperature changes.                             For the best cookware for gas stoves, look for ones that are made of stainless steel with aluminum or copper layers.             The average household gas stove looks like it can handle quite a bit. Its sizable build, durable fabrication, rugged cast iron grates, all signify a hard-wearing kitchen appliance.             Still, as with any appliance, especially one used practically every day to prepare food, it’s important to handle gas stoves with care. This means making sure the stove is well-maintained, properly cleaned, and used with the right cookware.                 While technically any pot or pan can be used on a gas stove, there are certain materials that are better suited for its open-flame style of cooking. We recommend our own stainless steel cookware for gas stoves. In this article, we’ll share what those materials are, explain why they work so well, and round up some of the best cookware for gas stoves available today.                 The Features of a Gas Stove                 Iron gas stove may be older than electric stoves, but they’re still the preferred option for a number of reasons.                 First and most important is how easy it is to adjust the heat of a gas stove. A burner can be turned on and off in an instant. And every twist of the control knob creates an immediate corresponding change in the burner’s flame level — a lightning quick heat response that’s crucial in cooking.                 Many cooks also like how the flames provide a convenient visual cue about the stove’s current heat setting. This can be a bit trickier to gauge with the dark glass tops of electric or induction cooktops.                An added bonus of the open flame is that it lends itself well to quickly roasting a few small items, like corn tortillas, bell peppers, or marshmallows.           Cooking with gas is also comparatively cheaper than cooking with electricity. Gas stoves generally run on propane, butane, petroleum, or natural gas, all of which are quite affordable. This gives gas stoves an advantage, not only for the cost-conscious home cook, but for anyone who finds themselves in the middle of a power outage.             As for cookware, gas stovetops easily accommodate a wide range. They can be used with just about any type of cookware material and shape — from small skillets to tall stockpots. Woks in particular were designed to be used over an open flame.             Flames, however, don't naturally distribute heat in a uniform manner. Some parts of a pan will have more contact with stronger flames than other parts, and the heat can be very concentrated, especially on a low setting.             Add this to a gas stove’s ability to change temperatures in an instant, and it's easy to see why it's so important to use cookware that can ably withstand these variations.         Choosing the Best Portable Gas Stove                 Portable gas stoves are crucial gear for the gourmet on the go. These stoves usually come with a burner and a cooking surface, and they let you boil, simmer, sauté, and fry. If you can do it on a stovetop at home, you can do it on a portable stove.                             Folding gas stove is different than a portable gas grills. Portable grills are similar to the grills you use at home. If you want to grill up hot dogs, chicken, or vegetables, you’re good to go with a portable grill. But sometimes you want more than your standard backyard barbecue menu, and that’s where a portable gas stove comes in. These have burners more like a traditional stove. They often come with containers to cook in, but many can also be used with other types of pots, pans, and skillets like a regular stovetop.                 What Kind of Portable Gas Stove Do You Need?                 The adventures you have on the trail aren’t like anyone else’s. Your needs and your priorities are unique. That’s why there are stoves for every type of outdoor explorer, from long-distance backpackers to car campers.                 As you think about your needs, there are some specific features you may want to think about:                 Size – If you’re hiking, you’ll want to save as much space and weight in your pack as possible. If you’re getting to base camp and setting up quickly, you might be more willing to haul a little more gear in the name of having the perfect home away from home.                             Fuel type – There are three main liquid fuels. Each have their own considerations and limitations. Then there’s our Jetpower fuel, which combines the benefits of both.                                             Propane is the most common camp stove fuel. It’s high-performance, and you can find it just about everywhere. Propane is what powers the Genesis base camp system, and Jetlink technology lets you build a high-efficiency network of burners from one propane tank.                         Isobutane has a lower boiling point, and it’s lighter. That means it’s easier to carry, and it’s more efficient in colder environments. However, it’s also more expensive.                         Butane is the cheapest fuel for a portable gas stove, but it’s also the least efficient and reliable. It has the highest boiling point and the lowest vapor pressure of the three gases.                         Jetpower is Jetboil’s engineered blend of propane and isobutane. It’s a unique mix that combines the best aspects of both, and it’s what we trust to power most of our stoves. Jetpower delivers high vapor pressure in all four seasons.                 Cost – Cost is certainly a factor in choosing a portable gas stove, and there are options at every price point. However, it’s worth noting that sometimes paying more up front can save money in the long run. A high-efficiency stove means you’ll spend less on fuel over time, and durable equipment means you won’t have to buy a replacement for a long time.                                         Durability – Most people want a stove that holds up outdoors as well as they do. Knowing that you’ve got a well-engineered stove means knowing you’ve got a reliable one.                             Number of burners – How big is the group that you’re feeding? If you’re solo, or just out with a partner, you can probably get away with one. But if you’re feeding a group, you may want a setup like the Genesis, which starts with two burners and can expand as your group dose.                 Utility – What are you cooking? Are you boiling soup? Are you making a three-course meal? The meals you plan to cook may be the biggest factor of all in choosing the stove that suits your needs.

Fecha de Publicación: 24-09-21

How to Choose a Transformer: Dry Type vs. Oil Cooled

Descripción: How to Choose a Transformer: Dry Type vs. Oil Cooled     Transformers are common and useful devices which take high voltage electricity directly from a power station and convert it to a lower voltage. This allows the energy to be safely and efficiently used by machinery and appliances that can only handle low voltage in spaces such as offices, transportation hubs, schools and factories.     Through this process transformers generate a lot of heat that must be dissipated to keep them running safely. There are two types of transformers being used in the industry currently: Dry-type transformers and oil-cooled transformers. Dry-type uses air as a cooling medium, and liquid cooled uses oil. Although both types have the same end result there are a number of differences between them worth noting, that will affect which type you choose.     Maintenance: Oil cooled transformers required more maintenance procedures, which must be performed more often than dry-type. The oil needs to be sampled to test for contamination, whereas dry type transformer is very resistant to chemical contaminants.     Costs (Initial and Operating): Compared to oil cooled, dry type has a significantly higher operating loss. Oil filled transformers have a higher standard energy efficiency, and as a result have a higher lifespan than dry type.     Noise: Oil cooled transformers have a lower operating sound level, thus less noise pollution than dry-type.     Recyclability: The end of life recycling for dry type is limited, while oil units boast an easier core/coil reclamation. Oil cooled have superior operating life and maintainability, producing less waste and requiring less replacements and labor.     Efficiency: Dry type transformers are larger units, limited in voltage and size, making them more prone to overheating if they experience overload. As a result, they have higher electrical losses, and it is more expensive to maintain dry type power supply over time. Oil cooled units are smaller and more efficient. They require less demand and create a smaller environmental footprint.     Voltage Capabilities: Dry type transformers are designed to handle small to medium MVA and voltage ratings, making them ideal for smaller applications. Oil cooled transformers can handle heavier loads, so applications that require higher voltages will require oil units.     Location: Location of the transformer will be the biggest determinant for which type you will need. Dry type is specified for use in buildings and near buildings, simply because they are environmentally safer. Dry type transformers are less flammable and pose less of a fire risk, making them ideal for shopping malls, hospitals, residential complexes and other commercial areas. Oil cooled transformers are used in outdoor installations due to the possibility of oil leakage and spills which pose a fire risk, but these units are more environmentally friendly.     Taking these variables into account, oil units appear to be the better option overall with higher energy efficiency, recyclability, low noise pollution, lower operational costs and a small environmental foot print. However, oil units simply cannot be used in any situation. Dry type is the best and many times, required option for commercial and indoor operations, because they are safer units to operate around people and areas where fire hazards may exist.         Types of transformer         Oil Immersed Transformer                                 As the name suggests the coils in this type of transformers are immersed in oil (mostly mineral oil) which helps in keeping the temperature of the transformer under control. This oil type transformer dissipates the through the radiators which are attached on the tank of the transformer and are referred to as ONAN type transformer. To further improve the cooling of the transformer the radiators are installed with fans which helps in bringing down the temperature and referred to as ONAF type transformer. This type of transformer can reach high voltage capacity, in some cases 1000kV.                                             Dry Type Transformer                                           In this type of transformer, air is used as the cooling medium. They are made using vacuum pressure impregnation in polyester or silicone varnish. Some of them are also made using VPI epoxy and cast resin for tougher environmental conditions. Since they are limited with regards to cooling aspect the maximum voltage is limited up to 35kV.           Switchgear     Switchgear is electrical distribution equipment: it accepts power from a source, routes it to a number of outputs and provides overcurrent protection and control functions. Of the types of distribution equipment described in the NFPA 70: National Electrical Code Article 408: Switchboards, Switchgear and Panelboards, switchgear is generally the most robustly constructed, the largest and the most expensive. It’s typically applied in high-reliability facilities, like hospitals or data centers, where continuity of power is critical to effective operation.     Switchgear is available in a wide range of voltage ratings, from below 1,000 volts to more than 200 kilovolts. Medium-voltage switchgear, rated above 1,000 volts, is manufactured by producers in a variety of configurations. Assemblies are available for exterior padmount installation, vault installation or installed in dedicated freestanding metal buildings, with air, gas, vacuum or oil as insulating media. This discussion will focus on interior low-voltage switchgear.     The alternative to switchgear is switchboard construction. Switchboards generally require less space and are less expensive. Both are typically constructed of a number of vertical sections. Each section is enclosed in sheet metal, with openings in front for overcurrent protection devices, monitoring equipment and control devices. A section may contain a main overcurrent protection device, metering devices, automatic control and monitoring systems, overcurrent protection devices for distribution feeders or a combination of these or other equipment specific to the installation. Overcurrent protection is typically accomplished with circuit breakers, with fused switches are less frequently.     Electric power substation     An assembly of equipment in an electric power system through which electrical energy is passed for transmission, distribution, interconnection, transformation, conversion, or switching. See Electric power systems     Specifically, substations are used for some or all of the following purposes: connection of generators, transmission or distribution lines, and loads to each other; transformation of power from one voltage level to another; interconnection of alternate sources of power; switching for alternate connections and isolation of failed or overloaded lines and equipment; controlling system voltage and power flow; reactive power compensation; suppression of overvoltage; and detection of faults, monitoring, recording of information, power measurements, and remote communications. Minor distribution or transmission equipment installation is not referred to as a substation.     Substations are referred to by the main duty they perform. Broadly speaking, they are classified as: transmission substations, which are associated with high voltage levels; and distribution substations, associated with low voltage levels. See Electric distribution systems     Substations are also referred to in a variety of other ways:     1. Transformer substations are substations whose equipment includes transformers.     2. Switching substations are substations whose equipment is mainly for various connections and interconnections, and does not include transformers.     3. Customer substations are usually distribution substations on the premises of a larger customer, such as a shopping center, large office or commercial building, or industrial plant.     4. Converter stations are complex substations required for high-voltage direct-current (HVDC) transmission or interconnection of two ac systems which, for a variety of reasons, cannot be connected by an ac connection. The main function of converter stations is the conversion of power from ac to dc and vice versa. The main equipment includes converter valves usually located inside a large hall, transformers, filters, reactors, and capacitors.     5. Most substation is installed as air-insulated substations, implying that the bus-bars and equipment terminations are generally open to the air, and utilize insulation properties of ambient air for insulation to ground. Modern substations in urban areas are esthetically designed with low profiles and often within walls, or even indoors.     6. Metal-clad substations are also air-insulated, but for low voltage levels; they are housed in metal cabinets and may be indoors or outdoors.     7. Acquiring a substation site in an urban area is very difficult because land is either unavailable or very expensive. Therefore, there has been a trend toward increasing use of gas-insulated substations, which occupy only 5–20% of the space occupied by the air-insulated substations. In gas-insulated substations, all live equipment and bus-bars are housed in grounded metal enclosures, which are sealed and filled with sulfur hexafluoride (SF6) gas, which has excellent insulation properties.     8. For emergency replacement or maintenance of substation transformers, mobile substations are used by some utilities.     An appropriate switching arrangement for “connections” of generators, transformers, lines, and other major equipment is basic to any substation design. There are seven switching arrangements commonly used: single bus; double bus, single breaker; double bus, double breaker; main and transfer bus; ring bus; breaker-and-a-half; and breaker-and-a-third. Each breaker is usually accompanied by two disconnect switches, one on each side, for maintenance purposes. Selecting the switching arrangement involves considerations of cost, reliability, maintenance, and flexibility for expansion.     A substation includes a variety of equipment. The principal items are transformers, circuit breakers, disconnect switches, bus-bars, shunt reactors, shunt capacitors, current and potential transformers, and control and protection equipment. See Circuit breaker, Electric protective devices, Electric switch, Relay, Transformer     Good substation grounding is very important for effective relaying and insulation of equipment; but the safety of the personnel is the governing criterion in the design of substation grounding. It usually consists of a bare wire grid, laid in the ground; all equipment grounding points, tanks, support structures, fences, shielding wires and poles, and so forth, are securely connected to it. The grounding resistance is reduced enough that a fault from high voltage to ground does not create such high potential gradients on the ground, and from the structures to ground, to present a safety hazard. Good overhead shielding is also essential for outdoor substations, so as to virtually eliminate the possibility of lightning directly striking the equipment. Shielding is provided by overhead ground wires stretched across the substation or tall grounded poles. See Grounding, Lightning and surge protection

Fecha de Publicación: 24-09-21

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