If there is phenol in the process pipeline and the temperature is 200 degrees, what material should be used for the gasket inside the stop valve on the pressure gauge?
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If there is phenol in the process pipeline and the temperature is 200 degrees, what material should be used for the gasket inside the stop valve on the pressure gauge?
I personally recommend using soft cutting gaskets, modified polytetrafluoroethylene gaskets, or flexible graphite gaskets such as Fluoric Sigma 500 or Fle*Carb
The melting point of tetrafluoroethylene is around 415 degrees Celsius; if annealed copper gaskets are used, it’s difficult to achieve a tight fit and leaks can occur easily
PEEK material can be considered for use as gaskets, as it can withstand temperatures of up to 260 degrees when used over extended periods of time. It is also resistant to corrosion, wear, high temperatures, and hydrolysis. It can fully meet just the requirements.
Is it resistant to phenol corrosion? Is it resistant to high pressure? The pressure is 20 kilograms
I couldn’t find any information on whether phenol is corrosive to PEEK; among the substances that are corrosive to PEEK, this material was not listed. At 200 degrees, the grade of PEEK with 30% glass fiber is suitable; a pressure of 20 kilograms poses no problem and is more than sufficient.
Graphite gaskets with high temperatures can definitely be used
The PTFE gasket at a temperature of 200 degrees is not suitable; copper can be used instead
Use a PTFE gasket; that’s the right choice. Hundreds of transmitters in the factory use this in their pressure gauge pressure guiding tubes, and it has proven to be very reliable over the years. Although copper gaskets provide good fastening performance, it is difficult for workers to tighten them; even a slight lack of force can result in leakage. This makes the operation cumbersome for workers and requires high technical skills.