May I ask, for hydrofluoric acid, what type of flange should be used: a necked weld-on flange or a necked butt-weld flange?
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May I ask, for hydrofluoric acid, what type of flange should be used: a necked weld-on flange or a necked butt-weld flange?
Hydrogen fluoride is highly hazardous; refer to GB50316 13.2.6 – Butt welding flanges should not be used
There’s another issue: according to 13.2.13, soft gaskets cannot be used. The suitable material for hydrogen fluoride is polytetrafluoroethylene. After looking for a while, it seems there is no suitable material for hard gaskets. Polytetrafluoroethylene-coated gaskets exist, but with such gaskets the metal part on the outside will get corroded; I’m not sure how to choose a gasket in this case
There’s another issue: according to 13.2.13, soft gaskets cannot be used. The suitable material for hydrogen fluoride is polytetrafluoroethylene. After looking for a while, it seems there is no suitable material for hard gaskets. Polytetrafluoroethylene-coated gaskets exist, but with such gaskets the metal part on the outside will get corroded; I’m not sure how to choose a gasket in this case
This post was last edited by 955559 on 2018-10-8 at 21:24. For stainless steel wafer butt weld flanges, feel free to contact me
13.2.13 It doesn’t say that soft gaskets cannot be used
We use the IDT 7551. You can find out by asking a manufacturer; it’s quick to find out