Thread seal tape

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Thread seal tape is wrapped around the threads, lubricating the connection and allowing the two pieces to be screwed deeper together. shirutepuShi Gong .jpg
Thread seal tape is wrapped around the threads, lubricating the connection and allowing the two pieces to be screwed deeper together.

Thread seal tape (also known as PTFE tape, Teflon tape, or plumber's tape) is a polytetrafluoroethylene (PTFE) film tape commonly used in plumbing for sealing pipe threads. The tape is sold cut to specific widths and wound on a spool, making it easy to wind around pipe threads. Thread seal tape lubricates allowing for a deeper seating of the threads, and it helps prevent the threads from seizing when being unscrewed. [1] The tape also works as a deformable filler and thread lubricant, helping to seal the joint without hardening or making it more difficult to tighten, [2] and instead making it easier to tighten. [1] It also protects the threads of both pieces from direct contact with each other and physical wear, and helps seal and prevent leaks from the connection.


Typically the tape is wrapped around a pipe's male threads three times before it is screwed into place. It is wrapped in the same direction the male threads go for tightening. The tape is commonly used commercially in applications including pressurized water systems, central heating systems, and air compression equipment.

Temperature Range: -268°C to +260°C (-450°F to +500°F). PTFE is completely stable up to +260˚C (500˚F). Decomposition is slow up to 400°C (750°F). Decomposition will occur on contact with open flames.


PTFE tape used for different sized fittings PTFE Rolls.png
PTFE tape used for different sized fittings
PTFE tape for natural gas FUM-lenta iz teflona.png
PTFE tape for natural gas

There are two US standards for determining the quality of any thread seal tape. MIL-T-27730A (an obsolete military specification still commonly used in industry in the US) requires a minimum thickness of 3.5 mils and a minimum PTFE purity of 99%. [3] The second standard, A-A-58092, [4] is a commercial grade which maintains the thickness requirement of MIL-T-27730A and adds a minimum density of 1.2 g/cm3. [4] Relevant standards may vary between industries; tape for gas fittings (to UK gas regulations) is required to be thicker than that for water. Although PTFE itself is suitable for use with high-pressure oxygen, the grade of tape must also be known to be free from grease.

Thread seal tape used in plumbing applications is most commonly white, but it is also available in various colors. It is often used to correspond to color coded pipelines (US, Canada, Australia and New Zealand: yellow for natural gas, green for oxygen, etc.). These color-codes for thread sealing tape were introduced by Bill Bentley of Unasco Pty Ltd in the 1970s. In the UK, tape is used from coloured reels, e.g. yellow reels for gas, green for oxygen.

In Europe, the BSI standard BS-7786:2006 specifies various grades and quality standards of PTFE thread sealing tape. [5]


PTFE tape applied on an NPT fitting, in the direction of the threads. PTFE Tape.png
PTFE tape applied on an NPT fitting, in the direction of the threads.

Thread seal tape is appropriate for use on tapered threads, where the sealing force is a wedge action. Parallel threads may not seal effectively with or without tape, as they are intended to be sealed by a gasket.

Thread seal tape is almost always applied by hand, although at least one machine is available for production wrapping of fittings. [6] [7] [8]

Thread seal tape is also commonly used in the stretching of body piercings, through a process known as taping, because it is inert and safe for this use. The wearer wraps a layer of tape around a plug and uses the jewelry, adding another layer every few days, thus gradually stretching the piercing. [9]


Overuse or misapplication of thread seal tape may be a hazard. Excess application of tape can prevent mating threads from fully engaging, reducing the shear point of the threads. Combining thread seal tape with a pipe dope compound can also overload threads. Also, internal overhangs of loose material may constrict a joint or slough off and form a foreign body that could jam a valve seat. Therefore, use of tape as a thread sealant is generally not considered appropriate in fluid power (hydraulic) systems. Overheating and subsequent decomposition of Teflon can produce perfluoroisobutene which is 10 times as toxic as phosgene. Inhalation of even a minute amount can be fatal.

Use of names

Familiarity with the Teflon brand of fluoropolymers has led to the name becoming a generic trademark, and the practice of any PTFE-based thread seal tape being referred to as "Teflon tape". Chemours, owner of the Teflon trademark, no longer manufactures any thread seal tape, [10] and objects to this practice. [11]

Most references to "plumber's tape" nowadays refer to thread seal tape; however, the original use in the plumbing trade describes a strap of material with holes in it used for supporting pipes and fixtures. [12]

Related Research Articles

Polytetrafluoroethylene Synthetic polymer

Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. The commonly known brand name of PTFE-based compositions is Teflon by Chemours, a spin-off from DuPont, which originally discovered the compound in 1938.

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Plumbing is any system that conveys fluids for a wide range of applications. Plumbing uses pipes, valves, plumbing fixtures, tanks, and other apparatuses to convey fluids. Heating and cooling (HVAC), waste removal, and potable water delivery are among the most common uses for plumbing, but it is not limited to these applications. The word derives from the Latin for lead, plumbum, as the first effective pipes used in the Roman era were lead pipes.

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Plumber Tradesperson specializing in water and sewage systems

A plumber is a tradesperson who specializes in installing and maintaining systems used for potable (drinking) water, and for sewage and drainage in plumbing systems.

Gasket Type of mechanical seal

A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. Given the potential cost and safety implications of faulty or leaking gaskets, it is critical that the correct gasket material is selected to fit the needs of the application. A Gasket is a deformable material that is used to create a static seal and maintain that seal under various operating conditions in a mechanical assembly.

A plumbing fixture is an exchangeable device which can be connected to a plumbing system to deliver and drain water.

Drain-waste-vent system

In modern plumbing, a drain-waste-vent is part of a system that allows air to enter a plumbing system to maintain proper air pressure to enable the removal of sewage and greywater from a dwelling. Waste is produced at fixtures such as toilets, sinks, and showers. As the water runs down, proper venting is required to avoid a vacuum from being created. As the water runs down air must be allowed into the waste pipe either through a roof vent, or the "drain waste vent" (DWV).

National pipe thread

American National Standard Pipe Thread standards, often called national pipe thread standards for short, are U.S. national technical standards for screw threads used on threaded pipes and pipe fittings. They include both tapered and straight thread series for various purposes including rigidity, pressure-tight sealing, or both. The various types are each named with a symbol and a full name; examples of the symbols include NPT, NPS, NPTF, NPSC, and others.

Hose clamp

A hose clamp is a device used to attach and seal a hose onto a fitting such as a barb or nipple.

Compression fitting

A compression fitting is a fitting used in plumbing and electrical conduit systems to join two tubes or thin-walled pipes together. In instances where two pipes made of dissimilar materials are to be joined, the fittings will be made of one or more compatible materials appropriate for the connection. Compression fittings for attaching tubing (piping) commonly have ferrules in them.

Screw thread A helical structure used to convert between rotational and linear movement or force

A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread and the latter called a tapered thread. A screw thread is the essential feature of the screw as a simple machine and also as a threaded fastener.

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Threaded pipe

A threaded pipe is a pipe with screw-threaded ends for assembly.

Coupling (piping)

A coupling is a very short length of pipe or tube, with a socket at one or both ends that allows two pipes or tubes to be joined, welded (steel), brazed or soldered together.

Piping and plumbing fitting

A fitting or adapter is used in pipe systems to connect straight sections of pipe or tube, adapt to different sizes or shapes, and for other purposes such as regulating fluid flow. These fittings are used in plumbing to manipulate the conveyance of water, gas, or liquid waste in domestic or commercial environments, within a system of pipes or tubes.

For the "Fiombonan'ny Fiangonana Kristiana eto Madagasikara" (FFKM) see Council of Christian Churches in Madagascar.

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  1. 1 2 Cauldwell, Rex (Sep 2, 2008). Taunton's Plumbing Complete: Expert Advice from Start to Finish. Taunton Press. p. 38. ISBN   9781561588558.
  2. Doran, David (Jul 24, 2013). Construction Materials Reference Book. Routledge. p. 274. ISBN   978-1135139216.
  3. "MIL-T-27730A, 15 Apr 1964, and Notice 1, 17 Jul 1994, and Notice2, 9 Feb 1998" (PDF). Whole Building Design Guide (WBDG). United States General Services Administration (GSA), via National Institute of Building Sciences. 1998.
  4. 1 2 "A-A-58092, 7 Jan 1997" (PDF). Whole Building Design Guide (WBDG). United States General Services Administration (GSA), via National Institute of Building Sciences. 1998.
  5. BS-7786:2006 Specification for unsintered PTFE tapes for general use
  6. "Thred Taper, automatic tape application machine".
  7. Assembly Magazine. 1 June 2000.Missing or empty |title= (help)
  8. "Automated teflon-tape wrapping". Machine Design. April 2002.
  9. Hedrick, Dale. "Ear Lobe Stretching FAQ". Onetribe. Archived from the original on 25 February 2009. Retrieved 9 November 2010.
  10. "History of Plumber's Tape". Chemours. Retrieved 2016-03-21.
  11. Real Teflon Brand
  12. "Pipe Fitting Accessories - Plumbing & Sanitation - Plumber's Tape - Galvanized". Downwind Marine. Archived from the original on 26 April 2018. Retrieved 28 December 2018. Example of the original strapping "plumber's tape".