Soft-sealed ball valves use PPL instead of PTFE
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I would like to ask the experts: For a steam pipeline with a design pressure of 300 degrees that is rated PN16, all hard-sealed valves of this rating use cemented carbide, while ball valves use PPL instead of PTFE. What could be the reason for this?
The possible reason is that PPL (polyphenylene sulfide) has better heat resistance at high temperatures compared to PTFE (polytetrafluoroethylene), and it also exhibits better pressure resistance under PN16 conditions. Therefore, in high-temperature steam pipes, it is more suitable to use PPL as a soft sealing material. .
The operating temperatures required for these two should not reach 300°C; neither material is suitable for such high temperatures. There is a problem with the design provided by the design institute.
Bro, what if it’s 250°C? I’m not sure if PPL will work
The maximum temperature tolerance of PPL material is 220°C, while the temperature for long-term use is 180°C; therefore, for your application, only hard-sealed ball valves can be used.
I wouldn’t dare call myself an expert; I’ve never actually used PPL, but from what I’ve read online, it seems to be usable. However, steam generally does not require soft seals.
The phrase \"a steam pipeline grade PN16 with a design pressure of 300 degrees\" is full of contradictions
The manufacturing standards of that unit are relatively poor; I think the pressure value is appropriate, but the temperature might be set too high
In the compound of a certain EI, the documents indicate that 300 degrees was used by PPL.