What materials are generally used for gaskets in low-temperature heat exchangers?
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I need to design two heat exchangers for foreign clients recently; they are of the pressurized type and operate in low-temperature conditions. I would like to know what materials are generally used for gaskets in low-temperature heat exchangers. As a supplementary note, the structure is shell-and-tube type, with fin arrays consisting of finned tubes. Last edited by vivo1314 on 2009-4-19 22:01
The take over can be selected in accordance with HG20592-20635--97, taking into account factors such as the properties of the material and the pressure level; alternatively, the equipment can be chosen based on JB/T 4704~4706-2000, again with consideration given to the material properties and pressure.
I am referring to low-temperature heat exchangers, namely those with a design temperature of less than -20 degrees Celsius
Flexible graphite composite gasket, wound gasket (stainless steel + graphite)
I have seen: graphite metal wound gaskets, 4F gaskets, asbestos gaskets
Gaskets made of polytetrafluoroethylene for low temperatures; this material is widely used in cryogenic equipment
Various rubber pads, with a minimum operating temperature of -50℃； Flexible graphite composite gasket, no temperature restrictions ； Various copper, aluminum, and stainless steel gaskets can be used down to at least -196°C.
It depends on the type of heat exchanger you use. If it is a plate heat exchanger, according to Appendix A of national standard 16409, the operating temperature range for gaskets is as follows: nitrile rubber: -20 to 110, EPDM: -50 to 150, fluororubber: 0 to 180, neoprene: -40 to 100, silicone rubber: -65 to 230, asbestos fiber board: 20 to 250. If your customer’s price is acceptable, silicone rubber should be a good choice. I still have one thing that’s unclear: the fluororubber is described as having excellent low-temperature performance, so why is the temperature specified here as 0 degrees?