Can asbestos rubber gaskets be used on CPVC, PP and other plastic pipes?
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Can asbestos rubber gaskets be used on CPVC, PP and other plastic pipes? Now in the construction service, the gaskets on CPVC, PP and other plastic pipes specified by our design institute during design are asbestos rubber sheets. However, Party A and the construction party believe that asbestos rubber sheets have no elasticity, and plastic pipe flanges cannot be tightened with great force, so they are prone to leakage when used on plastic pipes. Is this true? So what material is generally better to use? The solution is an acidic corrosive medium and contains chloride ions.
PLEASE USE THE FOLLOWING: GASKET CL150 FF 3.0 MM THCK FULL FACE PTFE PLUS FILLERS GARLOCK GYLON STYLE 3500 OR EQ. ASME B16.21 B16.5
According to the "General Installation Guidelines for Industrial Chlorinated Polyvinyl Chloride (PVC-C) Pipes", when connecting PVC-C pipe flanges, use an elastic gasket to seal between the two flanges. The material of the elastic gasket must be resistant to corrosion. I think acid and alkali resistant rubber plates can be used. Its use of flange installation mainly has the following requirements:: 1) Scope of application of pipe flange connection: It is generally used to connect PVC-C pipes with other types of pipes, valves, and equipment, and when the pipeline system needs to be temporarily repaired and disassembled or when adhesive connections cannot be made at the installation site. ； 2) Steps for pipe flange connection: (1) Bond the CPVC pipe and CPVC flange joint together according to the above method ； (2) The CPVC flange holes should be aligned with the flange holes of the connected pipes, valves, and equipment. ； (3) After the flange and the pipe are bonded and connected, the insertion time should be maintained and the flange connection should be made after 15 minutes of rest. (4) Use an elastic gasket to seal between the two flanges. The material of the elastic gasket must be corrosion-resistant. ； Insert bolts into matching holes, and spacers must be used under each nut and bolt. (5) Use a wrench to tighten the bolts symmetrically and tighten the bolts. Note: The pressure endured by the flange connection is basically set at 20°C. At higher temperatures, the pressure endured by the flange is calculated based on the pipeline system pressure correction coefficient. You can negotiate with the design institute.
After checking the information, I feel that the flatness and compressibility of the flange of the non-metallic pipe are not enough. Party A should be right. Asbestos rubber gaskets are indeed not good. I initially considered using soft PVC or fluorine rubber. (Ethylene-propylene rubber is not resistant to organic matter such as kerosene, so it was abandoned)
Generally, there are neoprene gaskets, which have good elasticity and are acid-resistant.
5# 1234wzw Just use soft PP