PTFE pipes are used in low-temperature applications

Tests, inspections, and application scope for PTFE lining layers: 1. Pipes and pipe fittings are subjected to hydrostatic testing at 1.5 times the design pressure. 2. For all cases involving a PTFE lining layer, a 100% integrity inspection is carried out after the hydrostatic test, and the leakage detection method employed is spark testing. 3. Usage specifications: a. Nominal diameter: DN25~DN600 b. Length: ≤2000mm c. Operating temperature: -20~150℃

The temperature can be tolerated, but I’m not sure about the pressure level~~ If the pressure is high, it’s recommended to use a PTFE lining ~~

This post was last edited by HaoYuBuQiZhi on December 1, 2015, at 15:13. For frozen water at 4 degrees Celsius, the pressure is probably not very high; thus, PE pipes should suffice. Using PTFE would be a waste. Furthermore, the installation of PTFE pipes is much more complicated than that of PE pipes.

PTFE of poor quality can withstand temperatures up to 150 degrees; higher-quality versions can handle temperatures ranging from -29 to 260 degrees without issue. Of course, for safety reasons, 230 degrees is often specified as the upper limit

How to distinguish the quality of PTFE materials? Are there any grade standards?

This post was last edited by od110 on 2016-12-21 at 16:25. To tell what’s good and what’s not, it depends on the brand – after all, you get what you pay for. Or, most intuitively, one can check its raw materials, or feel the finished product with their hands – it’s obvious that inner linings of average quality are made from PTFE particles, which are placed in molds and molded into shape. Such materials have a low density, high permeability, and poor tensile strength; they give a granular feel when touched by hand. High-quality products are made by using PTFE powder and extruding it at low temperatures in a paste form. It feels very smooth to the touch. Of course, the price difference is quite large. There are no grades, but there are standards; to determine the quality of a product, one simply needs to look at its manufacturing standards – things like tensile strength and the required values for material testing – and the differences can be significant. For example, this requirement is not specified in the national standard HG 3705 for lining materials; the best standards are the European standards, followed by the American standards and then the national standards. DIN 2848: Steel flanged pipes and lined steel and cast iron flanged fittings. ASTM F1545: Standard specification for ferroalloy pipes, fittings, and flanges with plastic lining. HG 3705-2003: Metal mesh polytetrafluoroethylene composite pipes and fittings. HG21562-92: Polytetrafluoroethylene-lined steel pipes and fittings

Then you specify to use PTFE powder, but this increases the cost significantly