PTFE material is a component very commonly used at plumbing, specially its tape format, for sealing thread accessories. We will see below some of its properties and advise.
PTFE means "polytetrafluoroethylene" and it is a type of plastic polymer, where the Hydrogen atoms have been substituted by Fluor atoms. Its chemical formula is (C2F4)n.
It was discovered by Roy J. Plunkett (1910-1994), chemist from the United States who spent all his labor life in the company DuPont, corporation that traded his discovery under the name of “Teflon”, the name the product was known.
Thanks to its great properties such as resistance to erosion and corrosion, because it is a good insulator and its thermal stability, it has multiple applications. It’s very well-known its use as non-adherent but very common between plumbers as well, who use it to lubricate and seal male tapered pipe thread’ accessories, both for fluid conduction and gas transport. The format for plumbing is usually tape, at different widths, facilitating its application around the threaded pieces. Depending on the brands, you can find it also in different colours, which may have different densities and so purposes, for instance the yellow one for gas.
The way of application of the PTFE tape is very important for the correct sealing, and will depend on how wide or of which quality the trade mark is. The tape is allowing to filling in the gaps between thread’s roots and crests, at the same time that provides lubrication to be more easily screwed together, facilitating the tightening up to deformation point, which is what guarantees the tight seal.
Correct application of the product is crucial in security terms, an excessive use or under-application may imply hermetic problems. Steps to follow for a proper application:
1/ clean the threads with a brush, to avoid any kind of dirt or dust;
2/ wrap the tape around the thread in the direction of the thread spiral, covering it but without going out from the thread perimeter;
3/ make sure the sealant product is properly placed and with enough quantity, but not excessive;
4/ press manually the tape against the bottom of the roots, and then you can introduce the male thread into the female thread and tighten them manually or by the use of a special tool.
As indicated, PTFE has got lots of properties, and their combination makes the PTFE into a unique product. Some of these properties are:
- Thermal stability: unalterable up to 260ºC
- Thermal conductivity
- Resistance to a big number of chemical products
- Resistance to radiations and light
- Flexibility
- Low coefficient of erosion and friction
- High non-adherence
- Good insulation feature