What gasket should be used to connect a pressure gauge or pressure transmitter to the pressure tap?
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For pressure gauges and pressure transmitters connected to pressure tapping pipes, what material should be used for the gaskets? What size and material should they be? I have organic materials here; for steam, PTFE is used. When I took them apart, I saw that the gaskets had melted.
We use annealed copper, which is generally used once only – it’s replaced after being assembled and disassembled once; of course, this depends on its compatibility with the medium
When the temperature exceeds 200 degrees, PTFE cannot be used; instead, annealed copper gaskets should be employed. The size of these gaskets can be determined according to specific requirements, with a thickness of 3 mm.
Annealed copper gaskets are usually supplied with PTFE coating; they cannot be used at the pressure tapping point, but can still be used somewhat at the transmitter
Tetrafluoro gaskets are a fairly common type of gasket, and basically nothing can corrode them. I’m not very convinced by your claim that it’s melted; unless you’ve indeed been exposed to high-temperature media, then it’s the same as what was said above – if even the gauge can’t withstand it, there’s no point in worrying about gaskets. In my opinion, PTFE gaskets are not suitable for use in common operating conditions in three situations: 1. High temperatures, as PTFE cannot withstand them ； 2. High pressure; the strength of tetrafluoro material is insufficient ； 3. Rare cases of corrosion; it seems that materials containing fluorine cannot be used. This is not clear. From past experience, PTFE is not used in oxygen pipelines due to concerns over rapid aging, and graphite is used instead.
If the temperature is high, copper gaskets can be considered; however, for pressure gauges and transmitters used to measure high-temperature media, a condenser must be installed to prevent damage to the PTFE gaskets. Otherwise, problems will arise with both the pressure gauge and the transmitter. Investigate the specific cause.
If the temperature is high, copper gaskets can be considered; however, for pressure gauges and transmitters used to measure high-temperature media, a condenser must be installed to prevent damage to the PTFE gaskets. Otherwise, problems will arise with both the pressure gauge and the transmitter. Investigate the specific cause.
Annealed copper gaskets are commonly used; in addition, there are also base-type graphite wound gaskets
For the gaskets behind the pressure-varying condenser, there are no major issues with using PTFE; as for the gaskets in front of the condenser, it’s better to choose annealed copper gaskets. I’ve also seen steel paper gaskets being used in applications involving low-pressure steam~~
Is the poster sure that F4 gaskets are being used for the steam pipes instead of metal-wound graphite gaskets? Discussing gasket selection without considering factors such as pipe diameter, material, properties of the fluid, and pressure isn’t it like trying to understand an elephant by feeling it blindly? :lol:lol
It is better to use metal wound gaskets.