In addition to standard PTFE and PFA lining, the protef, FLOWTEF andSPEED-LOCK product ranges are also available with Polypropylene and PVDF linings.
When used with compatible applications in terms of chemical resistance and temperature, they offer a superior resistance to permeation and a remarkable cost saving with respect to PTFE and PFA.
Polypropylene is a thermoplastic polymer and has a good chemical resistance to aqueous solutions of inorganic salts as well as almost all inorganic acids and bases. Provided temperatures are limited to +107°C, the minimum temperature is -20°C. PP lined steel pipes and fittings are not subject to dimensional instability or cracks as some solid plastic systems moreover they do not suffer from aging due to UV rays and weather
Polyvinylidene fluoride (PVDF) is a thermoplastic fluoropolymer with excellent chemical resistance and in difficult services such as Phosgene, Chlorine, Bromine, give better service than either PTFE and PFA. Compared to these materials, PVDF also has a better resistance to abrasion, it can withstand temperatures up to +135°C, the minimum temperature is -12°C.