How should the pressure rating be selected for mechanical seal selection?
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Dear experts: When selecting mechanical seals, should the design pressure rating be based on the pressure at the shut-off point of the pump outlet, or on the working pressure in the pump chamber at that shut-off point? Thank you.
Personally, I choose the latter; no explanation needed!
It should be the design pressure of the pump; this design pressure is definitely higher than the pressure at the closed outlet and the pressure inside the pump chamber when it is closed
The pressure in the sealed chamber is much lower than the outlet pressure of the pump
This post was last edited by COMPUMP_BZXS on 2018-2-12 at 16:49. The normal operating pressure is indeed lower than the pump outlet pressure, but standards require that the maximum allowable operating pressure in the sealing chamber be no less than the pump’s maximum allowable working pressure (MAWP). This applies to components that are under pressure, such as sealing gaskets; as for components that are not under pressure, such as springs, moving and stationary rings, and O-rings, it is not necessary, in my opinion. But for bellows as well, the requirements of standards should be taken into account.