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Which type of PVC sheet do I need for my application?

Descripción:     Which type of PVC sheet do I need for my application?     What is PVC (PolyVinyl Chloride)?     Polyvinyl Chloride (PVC or Vinyl) is an economical and versatile thermoplastic polymer widely used in building and construction industry to produce door and window profiles, pipes (drinking and wastewater), wire and cable insulation, medical devices, etc. It is the world’s third largest thermoplastic material by volume after polyethylene and polypropylene.     It is a white, brittle solid material available in powder form or granules. Due to its versatile properties, such as lightweight, durable, low cost and easy processability, PVC sheet is now replacing traditional building materials like wood, metal, concrete, rubber, ceramics, etc. in several applications.     Basic Forms of PVC(including PVC rod)     Polyvinyl Chloride is widely available in two broad categories: Flexible and Rigid. But, there are more types like CPVC, PVC-O and PVC-M.     Plasticized or Flexible PVC (Density: 1.1-1.35 g/cm3): Flexible PVC is formed by the addition of compatible plasticizers to PVC which lower the crystallinity. These plasticizers act like lubricants resulting in a much clearer and flexible plastic. This type of PVC is sometimes called as PVC-P.     Unplasticized or Rigid PVC (Density: 1.3-1.45 g/cm3): It is a stiff and cost-effective plastic with high resistance to impact, water, weather, chemicals and corrosive environments. This type of PVC is also known as UPVC, PVC-U or uPVC.     Chlorinated Polyvinyl Chloride or perchlorovinyl: It is prepared by chlorination of PVC resin. High chlorine content imparts high durability, chemical stability and flame retardancy. CPVC can withstand a wider range of temperatures.     Molecular Oriented PVC or PVC-O: It is formed by reorganizing the amorphous structure of PVC-U into a layered structured. Bi-axially oriented PVC has enhanced physical characteristics (stiffness, fatigue resistance, lightweight, etc.).     Modified PVC or PVC-M: It is an alloy of PVC formed by addition of modifying agents, resulting in enhanced toughness and impact properties.     Polyvinyl Chloride (PVC) is one of the most widely used polymers in the world. Due to its versatile nature, PVC, or other plastic rod, is used extensively across a broad range of  industrial, technical and everyday applications including widespread use in building, transport, packaging, electrical/electronic and healthcare applications.     PVC, including soft PVC sheet roll, is a very durable and long lasting material which can be used in a variety of applications, either rigid or flexible, white or black and a wide range of colours in between.     The essential raw materials for PVC are derived from salt and oil. The electrolysis of salt water produces chlorine, which is combined with ethylene (obtained from oil) to form vinyl chloride monomer (VCM). Molecules of VCM are polymerised to form PVC resin, to which appropriate additives are incorporated to make a customised PVC compound .     The PVC production process consists of 5 steps:     The extraction of salt and hydrocarbon resources     The production of ethylene and chlorine from these resources     The combination of chlorine and ethylene to make the vinyl chloride monomer (VCM)     The polymerisation of VCM to make poly-vinyl-chloride (PVC)     The blending of PVC polymer with other materials to produce different formulations providing a wide range of physical properties.     PVC sheet, PE sheet and PP sheet have excellent corrosion resistance and weather resistance. The working temp is 33 deg F to 160 deg F. and the forming temperatures of 245 deg F. It is good electrical and thermal insulator and has a self-extinguishing per UL Test 94. PVC applications are almost unlimited. It's the most widely used member of the vinyl family. It is excellent when used for corrosion-resistant tanks, ducts, fume hoods, and pipe. Ideal for self-supporting tanks, fabricated parts, tank linings, and spacers. It is not UV stabilized and has a tolerance of +or 10%. Not FDA approved materials. Colors available: Gray PVC Type 1 Sheet, White PVC, Clear PVC.    

Fecha de Publicación: 08-09-21

What Is a Brake Caliper

Descripción:     What Is a Brake Caliper     If your car is equipped with disc brakes, brake calipers are critical to slowing and stopping your car. Here's what you need to know.     The brake caliper plays a central role in a disc-brake system and has two functions. First, it acts either as a bracket to support the brake pads on either side of the rotor or to support the caliper bracket itself — there are other designs, but these are the two most common. Second, it uses pistons to convert pressure exerted on the brake fluid by the master cylinder into friction on the rotor.     In simple terms, a brake caliper’s purpose is to squeeze the brake pads against the rotor to stop the car. There are two main types of calipers, a single piston and a dual piston. Most front calipers are dual piston but many cars use single piston calipers on the rear, where less braking force is needed.     Stepping on the brake pedal forces the master cylinder piston forward, compressing the brake fluid. The brake fluid forces the brake caliper pistons toward the rotors, pinching the rotors in between the brake pads, which creates friction and slows the vehicle.     When Brake Calipers Go Bad     In general, brake pads and rotors wear out and need replacement far more often than calipers. A leading cause for damaged calipers, however, stems from driving a vehicle on worn-out pads or warped rotors. Both prevent the system from dissipating the heat of friction, as they’re designed to do, which can damage the calipers.     If the pads fail to insulate the caliper from excessive heat, the piston can be damaged or the heat can be passed through the piston to the brake fluid, which can cause it to degrade. The latter can result in brake failure.     A damaged piston, or one that is simply corroded, may get stuck in one position. If it sticks in the retracted position, that wheel will lose braking ability. If it sticks in the engaged position, the wheel will brake continuously until freed.     How to Tell That a Caliper Has Failed     With a retracted piston, the car may pull toward the side of the car with operating brakes when they are engaged. You may also notice that braking distance increases. Conversely, an engaged piston will cause the car to pull toward the engaged brake when driving. (Note: A stuck caliper can cause pulling, but there are many other possible causes as well.) Excess heat will be present, and the brake pad will quickly wear down. Any of these symptoms indicate immediate need for service.     Another sign of caliper failure could include leaking brake fluid, as a damaged piston may no longer seal completely. If enough fluid escapes from the system, the warning light on the dashboard will call your attention to it. If you check your pad wear regularly, you may note uneven wear on the pads, comparing one side of the rotor to the other, or even left wheel to right wheel. If the pads show uneven wear, check the caliper function. And yet another sign of a seized caliper is excessive brake dust on one wheel compared to the other.     In the rarest form of failure, the caliper bracket could snap, causing a clunking sound when the brakes engage. If you hear this, stop immediately and do not operate the vehicle.     Ignoring any of these symptoms can magnify the damage. The cost and effort required to address the problem increases proportionally. Make an effort to examine the problem as soon as possible or have it evaluated by a qualified technician.     Important Maintenance Points     ? As the brake pads wear, the caliper needs to stay centered on the rotor to allow for even pressure on both sides. There are different ways manufacturers accomplish this, and some designs are better than others at keeping the calipers sliding to compensate for pad wear. When brake service is done, always clean and grease the sliding mechanisms with a high-temp brake grease to preserve the full range of travel. If not properly lubricated, calipers can lock in one position, resulting in only one pad getting proper pressure on the rotor.     ? Whenever possible, inspect the dust boots protecting the caliper piston and the two slide pins. These flexible covers prevent dirt and moisture from fouling the action of the associated parts. Any damage or tears found in the boots must be addressed quickly, before dirt and corrosion cause the parts to seize. It is possible to disassemble the caliper, clean the parts and replace the boots if you have some skill as a DIYer. Labor charges, however, make this impractical in most auto shop situations, so the most common resolution is full replacement of the caliper and bracket.     Regardless of the type of support, it is designed to have parts that withstand increased wear. The pads and discs we have not considered because they are considered consumables. As for the support, the return movement of the piston is provided by a rubber sleeve. When the driver depresses the brake pedal, the piston comes out of the body and deforms the brake sleeve kit, when the pedal is released, the cuff tends to present a starting position and drags the piston.     The brake system includes brake calipers, brake discs, brake pads(including brake pad fitting kits), steel pipes, brake fluid, etc. There are also brake rubber dust cover kits.

Fecha de Publicación: 08-09-21

What uses does rubbing alcohol have?

Descripción:     What uses does rubbing alcohol have?     Wound Dressings     Wound, whether it is a minor cut or a major incision, it is important to care for it properly, part of this process includes wound dressing. Dressing is designed to be in contact with the wound, which is different from a bandage that holds the dressing in place. Historically, wet-to-dry dressings have been used extensively for wounds requiring debridement. In 1600 BC, Linen strips soaked in oil or grease covered with plasters was used to occlude wounds. Clay tablets were used for the treatment of wounds by Mesopotamian origin from about 2500 BCE. They cleaned wounds with water or milk prior to dressing with honey or resin. Wine or vinegar usage for cleaning the wounds with honey, oil and wine as further treatment was followed by Hippocrates of ancient Greece in 460- 370 BCE. They used wool boiled in water or wine as a bandage. There was a major breakthrough in the antiseptic technique during the 19th century, antibiotics were introduced to control infections and decrease mortality. Modern wound dressing arrival was in 20th century.     When the wound is closed with dressing, such as transparent film dressing, they are continuously exposed to proteinases, chemotactic, complement & growth factors, which is lost in the wound exposed. So during late 20th century, production of occlusive dressing began to protect and provide moist environment to wound. These dressings helps in faster re-epithelialization, collagen synthesis, promotes angiogenesis by creating hypoxia to the wound bed and decreases wound bed pH which leads to decrease in the wound infection. Woven absorbent cotton gauze was used in 1891. Until the mid 1900’s, it was firmly believed that wounds healed more quickly if kept dry and uncovered whereas ‘closed wounds heal more quickly than open wound’ written in an Egyptian medical text -Edwin smith surgical papyrus in 1615 BC. Oscar Gilje in 1948 describes moist chamber effect for healing ulcers. In the mid 1980’s, the first modern wound dressing were introduced which delivered important characteristics providing moisture and absorbing fluids (e.g. polyurethane foams, hydrocolloids, iodine-containing gels). During the mid 1990’s, synthetic wound dressings expanded into various group of products which includes hydrogels, hydrocolloids, alginates, synthetic foam dressing, silicone meshes, tissue adhesives, vapor-permeable adhesive films and silver/collagen containing dressing.     Traditional wound dressing     Traditional wound dressing products including gauze, lint, plasters, bandages (natural or synthetic) and cotton wool are dry and used as primary or secondary dressings for protecting the wound from contaminations. Gauze dressings made out of woven and non woven fibres of cotton, rayon, polyesters afford some sort of protection against bacterial infection. Some sterile gauze pads are used for absorbing exudates and fluid in an open wound with the help of fibres in these dressings. These dressings require frequent changing to protect from maceration of healthy tissues. Gauze dressings are less cost effective. Due to excessive wound drainage, dressings, including foam dressing, become moistened and tend to become adherent to the wound making it painful when removing. Bandages made out of natural cotton wool and cellulose or synthetic bandages made out of polyamide materials perform different functions. For instance, cotton bandages are used for retention of light dressings with non woven dressing, high compression bandages and short stretch compression bandages provide sustained compression in case of venous ulcers. Xeroform? (non-occlusive dressing) is petrolatum gauze with 3% of Bismuth tribromophenate used for non-exudating to slight exudating wounds. Tulle dressings such as Bactigras, Jelonet, Paratulle are some examples of tulle dressings commercially available as impregnated dressings with paraffin and suitable for superficial clean wound. Generally traditional dressings are indicated for the clean and dry wounds with mild exudate levels or used as secondary dressings. Since traditional dressings fail to provide moist environment to the wound they have been replaced by modern dressings with more advanced formulations.     Modern and advanced wound dressing     Modern wound dressing have been developed to facilitate the function of the wound rather than just to cover it. These dressings are focused to keep the wound from dehydration and promote healing. Based on the cause and type of wound, numerous products are available in the market, making the selection a very difficult task. Modern wound dressings, transparent dressing with absorbent pad, are usually based on synthetic polymers and are classified as passive, interactive and bioactive products. Passive products are non-occlusive, such as gauze and tulle dressings, used to cover the wound to restore its function underneath. Interactive dressings are semi-occlusive or occlusive, available in the forms of films, foam, hydrogel and hydrocolloids. These dressings act as a barrier against penetration of bacteria to the wound environment.     What uses does rubbing alcohol have?     Rubbing alcohol is a common household chemical. It has several potential uses in personal care, as well as in general household cleaning.     However, the incorrect use of rubbing alcohol can cause serious side effects, including skin irritation and poisoning.     In this article, we list some common uses for rubbing alcohol. We also outline some situations in which a person should avoid using this chemical.     Common uses for rubbing alcohol, or alcohol pad, include:     1. Disinfecting tick bites     People can use tweezers to remove a tick carefully from the skin. Following its removal, they can use rubbing alcohol to disinfect the bite. They should apply rubbing alcohol to a cotton swab and dab it onto the area where the tick had attached itself.     2. Caring for pierced ears     According to the American Academy of Dermatology (AAD), people can use rubbing alcohol to help clean the skin around new ear piercings. To do this, a person should dip a cotton ball or pad into the rubbing alcohol. They should then gently wipe it around the piercing on the front and back of the ear.     People should clean the piercing twice a day to help prevent bacterial infections and scabbing.     It is important to note that some experts disagree with this advice, recommending that people avoid using rubbing alcohol because it might slow the healing process.     3. Reducing body odor     Rubbing alcohol can help kill odor-causing bacteria, and it can be used in woundcare dressing, or hydrocolloid dressing. A person can apply rubbing alcohol under the armpits to help eliminate body odors.     However, they should avoid applying rubbing alcohol soon after shaving, as this will cause stinging.     4. Deodorizing shoes     Shoes can develop a strong odor, particularly if a person wears them while exercising or doing other physical activity. Spraying the insoles of the shoes with rubbing alcohol can help eliminate odor-causing bacteria.     A person should fill a spray bottle with rubbing alcohol and use this to spray the insides of the shoes. Leaving the shoes in the sun will help dry them out.     5. Creating homemade room deodorizer     It is possible to make a room deodorizer by pouring rubbing alcohol into a spray bottle and adding a few drops of an essential oil. A person can then spray the mixture around the room to help mask unpleasant odors.     6. Creating homemade ice packs     By mixing water and rubbing alcohol, a person can create a reusable and malleable homemade ice pack. They can follow these steps:     Fill a sealable freezer bag with 2 cups of water and 1 cup of 70% rubbing alcohol.     Push as much air out as possible, and seal the bag.     Place the filled bag inside another freezer bag, pushing out as much air as possible before sealing it.     Freeze for several hours.     Once the ice pack is ready, people can apply it to sore muscles or joints to relieve pain and inflammation.     7. Cleaning and disinfecting hard surfaces     Rubbing alcohol can help clean and disinfect hard surfaces. It is effective against most, but not all, pathogens.     The main ingredient in rubbing alcohol is isopropyl alcohol (IA). Most rubbing alcohols contain about 70% IA, but the amount can range from 60% to 99%, depending on the product.     According to the Centers for Disease Control and Prevention (CDC)Trusted Source, alcohol solutions are most effective at concentrations of 60–90%. People should avoid using diluted solutions that have a concentration of 50% or below, as these will be less effective in killing pathogens.     8. Disinfecting sponges and cloths     Rubbing alcohol can also help disinfect household items, such as bathroom or kitchen sponges or cleaning cloths.     A person should pour some rubbing alcohol onto the sponge or cloth and let it soak for several minutes or hours inside a sealable container.     9. Cleaning and sanitizing electronic devices     Alcohol evaporates quickly and can kill pathogens on phones, laptops, tablets, and other devices. It is best to use a rubbing alcohol with 99% IA for electronics.     A person should apply a small amount of the rubbing alcohol to a paper towel or cloth and gently wipe it across the electronic device.     This chemical can also help remove water from an electronic device if a person accidentally drops it into water or spills some water on it. If the device was switched off at the time, removing water with the rubbing alcohol should recover it.

Fecha de Publicación: 08-09-21

What uses does rubbing alcohol have?

Descripción:     What uses does rubbing alcohol have?     Wound Dressings     Wound, whether it is a minor cut or a major incision, it is important to care for it properly, part of this process includes wound dressing. Dressing is designed to be in contact with the wound, which is different from a bandage that holds the dressing in place. Historically, wet-to-dry dressings have been used extensively for wounds requiring debridement. In 1600 BC, Linen strips soaked in oil or grease covered with plasters was used to occlude wounds. Clay tablets were used for the treatment of wounds by Mesopotamian origin from about 2500 BCE. They cleaned wounds with water or milk prior to dressing with honey or resin. Wine or vinegar usage for cleaning the wounds with honey, oil and wine as further treatment was followed by Hippocrates of ancient Greece in 460- 370 BCE. They used wool boiled in water or wine as a bandage. There was a major breakthrough in the antiseptic technique during the 19th century, antibiotics were introduced to control infections and decrease mortality. Modern wound dressing arrival was in 20th century.     When the wound is closed with dressing, such as transparent film dressing, they are continuously exposed to proteinases, chemotactic, complement & growth factors, which is lost in the wound exposed. So during late 20th century, production of occlusive dressing began to protect and provide moist environment to wound. These dressings helps in faster re-epithelialization, collagen synthesis, promotes angiogenesis by creating hypoxia to the wound bed and decreases wound bed pH which leads to decrease in the wound infection. Woven absorbent cotton gauze was used in 1891. Until the mid 1900’s, it was firmly believed that wounds healed more quickly if kept dry and uncovered whereas ‘closed wounds heal more quickly than open wound’ written in an Egyptian medical text -Edwin smith surgical papyrus in 1615 BC. Oscar Gilje in 1948 describes moist chamber effect for healing ulcers. In the mid 1980’s, the first modern wound dressing were introduced which delivered important characteristics providing moisture and absorbing fluids (e.g. polyurethane foams, hydrocolloids, iodine-containing gels). During the mid 1990’s, synthetic wound dressings expanded into various group of products which includes hydrogels, hydrocolloids, alginates, synthetic foam dressing, silicone meshes, tissue adhesives, vapor-permeable adhesive films and silver/collagen containing dressing.     Traditional wound dressing     Traditional wound dressing products including gauze, lint, plasters, bandages (natural or synthetic) and cotton wool are dry and used as primary or secondary dressings for protecting the wound from contaminations. Gauze dressings made out of woven and non woven fibres of cotton, rayon, polyesters afford some sort of protection against bacterial infection. Some sterile gauze pads are used for absorbing exudates and fluid in an open wound with the help of fibres in these dressings. These dressings require frequent changing to protect from maceration of healthy tissues. Gauze dressings are less cost effective. Due to excessive wound drainage, dressings, including foam dressing, become moistened and tend to become adherent to the wound making it painful when removing. Bandages made out of natural cotton wool and cellulose or synthetic bandages made out of polyamide materials perform different functions. For instance, cotton bandages are used for retention of light dressings with non woven dressing, high compression bandages and short stretch compression bandages provide sustained compression in case of venous ulcers. Xeroform? (non-occlusive dressing) is petrolatum gauze with 3% of Bismuth tribromophenate used for non-exudating to slight exudating wounds. Tulle dressings such as Bactigras, Jelonet, Paratulle are some examples of tulle dressings commercially available as impregnated dressings with paraffin and suitable for superficial clean wound. Generally traditional dressings are indicated for the clean and dry wounds with mild exudate levels or used as secondary dressings. Since traditional dressings fail to provide moist environment to the wound they have been replaced by modern dressings with more advanced formulations.     Modern and advanced wound dressing     Modern wound dressing have been developed to facilitate the function of the wound rather than just to cover it. These dressings are focused to keep the wound from dehydration and promote healing. Based on the cause and type of wound, numerous products are available in the market, making the selection a very difficult task. Modern wound dressings, transparent dressing with absorbent pad, are usually based on synthetic polymers and are classified as passive, interactive and bioactive products. Passive products are non-occlusive, such as gauze and tulle dressings, used to cover the wound to restore its function underneath. Interactive dressings are semi-occlusive or occlusive, available in the forms of films, foam, hydrogel and hydrocolloids. These dressings act as a barrier against penetration of bacteria to the wound environment.     What uses does rubbing alcohol have?     Rubbing alcohol is a common household chemical. It has several potential uses in personal care, as well as in general household cleaning.     However, the incorrect use of rubbing alcohol can cause serious side effects, including skin irritation and poisoning.     In this article, we list some common uses for rubbing alcohol. We also outline some situations in which a person should avoid using this chemical.     Common uses for rubbing alcohol, or alcohol pad, include:     1. Disinfecting tick bites     People can use tweezers to remove a tick carefully from the skin. Following its removal, they can use rubbing alcohol to disinfect the bite. They should apply rubbing alcohol to a cotton swab and dab it onto the area where the tick had attached itself.     2. Caring for pierced ears     According to the American Academy of Dermatology (AAD), people can use rubbing alcohol to help clean the skin around new ear piercings. To do this, a person should dip a cotton ball or pad into the rubbing alcohol. They should then gently wipe it around the piercing on the front and back of the ear.     People should clean the piercing twice a day to help prevent bacterial infections and scabbing.     It is important to note that some experts disagree with this advice, recommending that people avoid using rubbing alcohol because it might slow the healing process.     3. Reducing body odor     Rubbing alcohol can help kill odor-causing bacteria, and it can be used in woundcare dressing, or hydrocolloid dressing. A person can apply rubbing alcohol under the armpits to help eliminate body odors.     However, they should avoid applying rubbing alcohol soon after shaving, as this will cause stinging.     4. Deodorizing shoes     Shoes can develop a strong odor, particularly if a person wears them while exercising or doing other physical activity. Spraying the insoles of the shoes with rubbing alcohol can help eliminate odor-causing bacteria.     A person should fill a spray bottle with rubbing alcohol and use this to spray the insides of the shoes. Leaving the shoes in the sun will help dry them out.     5. Creating homemade room deodorizer     It is possible to make a room deodorizer by pouring rubbing alcohol into a spray bottle and adding a few drops of an essential oil. A person can then spray the mixture around the room to help mask unpleasant odors.     6. Creating homemade ice packs     By mixing water and rubbing alcohol, a person can create a reusable and malleable homemade ice pack. They can follow these steps:     Fill a sealable freezer bag with 2 cups of water and 1 cup of 70% rubbing alcohol.     Push as much air out as possible, and seal the bag.     Place the filled bag inside another freezer bag, pushing out as much air as possible before sealing it.     Freeze for several hours.     Once the ice pack is ready, people can apply it to sore muscles or joints to relieve pain and inflammation.     7. Cleaning and disinfecting hard surfaces     Rubbing alcohol can help clean and disinfect hard surfaces. It is effective against most, but not all, pathogens.     The main ingredient in rubbing alcohol is isopropyl alcohol (IA). Most rubbing alcohols contain about 70% IA, but the amount can range from 60% to 99%, depending on the product.     According to the Centers for Disease Control and Prevention (CDC)Trusted Source, alcohol solutions are most effective at concentrations of 60–90%. People should avoid using diluted solutions that have a concentration of 50% or below, as these will be less effective in killing pathogens.     8. Disinfecting sponges and cloths     Rubbing alcohol can also help disinfect household items, such as bathroom or kitchen sponges or cleaning cloths.     A person should pour some rubbing alcohol onto the sponge or cloth and let it soak for several minutes or hours inside a sealable container.     9. Cleaning and sanitizing electronic devices     Alcohol evaporates quickly and can kill pathogens on phones, laptops, tablets, and other devices. It is best to use a rubbing alcohol with 99% IA for electronics.     A person should apply a small amount of the rubbing alcohol to a paper towel or cloth and gently wipe it across the electronic device.     This chemical can also help remove water from an electronic device if a person accidentally drops it into water or spills some water on it. If the device was switched off at the time, removing water with the rubbing alcohol should recover it.

Fecha de Publicación: 08-09-21

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