Lubricated Compound Expands Advantages Of Tpvs Over Rubber In Seals And Gaskets For Pipes

Lubricated compound expands advantages of TPVs over rubber in seals and gaskets for pipes

22-Jun-16

A new thermoplastic vulcanizate (TPV) elastomer for pipe seals exhibits the same processing and performance advantages over thermoset rubber as a well-established TPV while providing enhanced lubricity for faster insertion of seals and more error-free assembly, it was announced today by Teknor Apex Company. For use in seals for non-pressure water and drain pipe, Sarlink® 9156-02 provides physical properties nearly identical to those of Sarlink 9156B, a workhorse compound for pipe seals, but as a lubricated compound it exhibits a coefficient of friction that is only 16% as high.
“The substantially greater lubricity of new Sarlink 9156-02 is a big advantage for inserting the seals into the fittings—a mechanical process in which lubrication increases speed and helps to prevent rejects,” said Stef Hordijk, general sales manager for the Thermoplastic Elastomer Division of Teknor Apex. “Fittings with lubricated seals also facilitate pipe insertion, which is done by hand at the construction site. By reducing the forces needed for inserting the pipe into the fitting, lubrication helps prevent improper assembly and damage to the seal.”
Like Sarlink 9156B, the new lubricated compound exhibits greater retention of sealing force over a period of years than rubber, prolonging the working lives of pipe seals, which must prevent leakage from within the pipe and seepage from outside. Sealing force is measured by the degree of stress relaxation. Compared with rubber, both TPVs exhibit lower levels of stress relaxation over a period of years, particularly at elevated temperatures. Both TPVs also make possible substantially greater productivity than rubber by eliminating the crosslinking step, by being processable on standard thermoplastic equipment with much less scrap, and by providing the capability of two-component molding. “The ability to be two-component molded is a key advantage of Sarlink compounds for pipe seals,” said Chris Smith, senior market manager. “This has made it possible to create seals as single, integral parts that combine the sealing performance of elastomers with the rigidity of materials like polypropylene or higher-durometer TPVs. The two-component seals differ in design from rubber seals, providing easier and more effective ways to position the seal in the fitting. By contrast, rubber seals have typically been single-component items that are made thicker to provide sufficient rigidity to hold the seal in place.”