Teflon is useful in multiple other industries
Food processingComponents and linings made with DuPont™ Teflon® can help cut equipment maintenance costs, increase uptime, increase throughput, and safeguard product purity. They also allow use of the same equipment to make a wider range of food products. Easy cleaning reduces the frequency, amount, and severity of cleaning chemicals used in processing facilities -- a benefit to the environment. Reduced downtime for cleaning can potentially improve plant productivity by 15-25%!
Not even the stickiest food products and biomaterials adhere well to DuPont™ Teflon®. Surfaces of Teflon® are easy to clean, and they stay cleaner longer. The payoff: faster, easier cleaning and longer intervals between cleanings. As an alternative to stainless steel, exotic alloys, and many other polymers, DuPont™ Teflon® fluoropolymers deliver more value and performance in food processing uses. Applications include linings for metal vessels, piping, pumps, and valves; pipe, hose, and tubing; components for valves and pumps; and seals and gaskets. Teflon® is impervious to attack by the fastest-acting and strongest cleaning agents and solvents we've tested. Many components made with Teflon® can be steam cleaned. For most plastics, that's out of the question. |
Pharmaceutical and Biopharma ManufacturingMany of today's pharmaceutical and biopharmaceutical manufacturing facilities must be flexible to produce multiple products while meeting both traditional and growing needs for product purity, cleanability, durability and low maintenance costs.
To meet these demands, engineers are turning to piping, components and vessels made with DuPont fluoropolymers. Traditional stainless steel and glass no longer deliver the best results. Teflon® PTFE, Teflon® PFA, Teflon® FEP and Tefzel® ETFE are strong candidates for pharmaceutical and biopharmaceutical processing equipment because they have excellent chemical and thermal resistance. Their molecules have continuous non-reactive surfaces and are compatible with virtually all chemicals and solvents. They are far more resistant to chemical attack than conventional chlorinated and hydrocarbon plastics, and have far higher service temperatures. Because Teflon® is non-reactive, there are no corrosion byproducts or extractables to contaminate processes. Teflon® is extremely pure, and it resists sorption of chemicals. Teflon® provides smooth non-wetting hydrophobic surfaces that resist biofilm buildup, and it can be used with the strongest cleaning solutions and steam-in-place processes. Surfaces of Teflon® are easy to clean, and because they resist buildup of process materials, it may be possible to extend intervals between cleanings. |
AnaLog’s Teflon wire
Teflon insulated wire is wonderful stuff. If you are accustomed to fighting insulation melt-back with ordinary PVC hook-up wire, you are in for a treat when you try Teflon (you cannot hurt it with a soldering iron). Teflon wire has been used in downhole logging tools almost exclusively since the 1960s because of its excellent high temperature performance. Some manufacturers have also used it in logging surface electronics. AnaLog Services, Inc. uses Teflon wire for all well logging electronics applications.
Teflon insulated wire is made using several techniques, including extrusion and wrapping. The extruded type is most commonly used in logging tools and surface electronics, usually in stranded sizes 22 and 24 AWG. Smaller sizes are found in the smaller diameter production logging tools where space is at a premium, and as inductor leads (high voltage transformers and the like). Miniature Teflon coaxial cable is also commonly found in well logging electronics; it often has the wrapped and fused type Teflon as the outer jacket insulation.
Teflon wire is available in a wide variety of colors. For the most part, the well logging industry has adopted the color code scheme used by the military. Said scheme uses the same numbering as resistor color codes, with black = 0, brown = 1, red = 2, orange = 3, yellow = 4, green = 5, blue = 6, violet (purple) = 7, gray (slate) = 8, and white = 9. There has been less agreement historically within the logging industry over the numbering scheme for the multi-colored striped wires. Unfortunately, the wire manufacturing industry has never established standards for color shades; actual wire colors vary over a wide range. Some of the Teflon wire insulation colors can be very pretty, almost with a glowing or neon quality.
Why silver plated?
Teflon wire is usually silver plated, as is most wire rated for use at over 125°C. At high temperatures, and over time, tin plating or solder tinning can dissolve into the underlying copper wire, leaving a surface that is difficult to solder. Silver plating can withstand higher temperatures for longer periods of time than can conventional tinning. Further, at the temperatures Teflon insulation is extruded and cured, individually tinned strands would be effectively soldered together to make a solid wire. Freshly stripped Teflon wire is truly beautiful with its white silver luster. But silver plated wire tarnishes (just like silverware); it should not be stored near sources of sulfur fumes such as cardboard, paper, rubber bands, etc. Teflon insulated silver plated copper wire is fairly immune to tarnish, but sometimes it is necessary to cut off and discard an inch or two if discoloration is seen at the end.
Wire stripping
Only stranded wire should be used in well logging electronics. Long experience has shown that solid hook-up wire fails long before stranded wire, probably because of vibration during transport more than anything else. However, improperly stripped (nicked) stranded Teflon wire often fails at the connection point. (An alternative theory holds that these failures are related to solder wicking up the silver plated wire strands, but proper stripping seems to eliminate most of the failures.) A common complaint heard about Teflon wire is that it is hard to strip. Most authorities recommend expensive automatic stripping tools with special Teflon insulation cutting dies installed. These gizmos cost a small fortune, we hate their cumbersome action, and they do not always do such a great job.
Expensive and Worth It
Teflon insulated wire is expensive, several times more expensive than ordinary PVC insulated wire. One manufacturer's published literature states the cost is eight to ten times as great. Unfortunately, in recent years, the audiophile community has driven surplus Teflon wire prices up considerably. These folks believe they can actually hear an improvement when audio equipment is constructed with Teflon wire. This is of course utter nonsense, but they sure buy a bunch of Teflon wire, thus driving up the surplus prices.
Teflon insulated wire is made using several techniques, including extrusion and wrapping. The extruded type is most commonly used in logging tools and surface electronics, usually in stranded sizes 22 and 24 AWG. Smaller sizes are found in the smaller diameter production logging tools where space is at a premium, and as inductor leads (high voltage transformers and the like). Miniature Teflon coaxial cable is also commonly found in well logging electronics; it often has the wrapped and fused type Teflon as the outer jacket insulation.
Teflon wire is available in a wide variety of colors. For the most part, the well logging industry has adopted the color code scheme used by the military. Said scheme uses the same numbering as resistor color codes, with black = 0, brown = 1, red = 2, orange = 3, yellow = 4, green = 5, blue = 6, violet (purple) = 7, gray (slate) = 8, and white = 9. There has been less agreement historically within the logging industry over the numbering scheme for the multi-colored striped wires. Unfortunately, the wire manufacturing industry has never established standards for color shades; actual wire colors vary over a wide range. Some of the Teflon wire insulation colors can be very pretty, almost with a glowing or neon quality.
Why silver plated?
Teflon wire is usually silver plated, as is most wire rated for use at over 125°C. At high temperatures, and over time, tin plating or solder tinning can dissolve into the underlying copper wire, leaving a surface that is difficult to solder. Silver plating can withstand higher temperatures for longer periods of time than can conventional tinning. Further, at the temperatures Teflon insulation is extruded and cured, individually tinned strands would be effectively soldered together to make a solid wire. Freshly stripped Teflon wire is truly beautiful with its white silver luster. But silver plated wire tarnishes (just like silverware); it should not be stored near sources of sulfur fumes such as cardboard, paper, rubber bands, etc. Teflon insulated silver plated copper wire is fairly immune to tarnish, but sometimes it is necessary to cut off and discard an inch or two if discoloration is seen at the end.
Wire stripping
Only stranded wire should be used in well logging electronics. Long experience has shown that solid hook-up wire fails long before stranded wire, probably because of vibration during transport more than anything else. However, improperly stripped (nicked) stranded Teflon wire often fails at the connection point. (An alternative theory holds that these failures are related to solder wicking up the silver plated wire strands, but proper stripping seems to eliminate most of the failures.) A common complaint heard about Teflon wire is that it is hard to strip. Most authorities recommend expensive automatic stripping tools with special Teflon insulation cutting dies installed. These gizmos cost a small fortune, we hate their cumbersome action, and they do not always do such a great job.
Expensive and Worth It
Teflon insulated wire is expensive, several times more expensive than ordinary PVC insulated wire. One manufacturer's published literature states the cost is eight to ten times as great. Unfortunately, in recent years, the audiophile community has driven surplus Teflon wire prices up considerably. These folks believe they can actually hear an improvement when audio equipment is constructed with Teflon wire. This is of course utter nonsense, but they sure buy a bunch of Teflon wire, thus driving up the surplus prices.