Minor Gasket Leakage During Cooldowns
Minor Gasket Leakage During Cooldowns
(OP)
This may qualify for stupid question of the year, but...
Does anyone know how cooling down a system (dropping both temperature and pressure) affects leakage through gaskets as compared to full power operation? My practical experience is that when a system is heating up, minor gasket leakage tends to disappear and generally does not reappear. However, I haven't been able to find anything about minor leakage that shows up during shutdowns - if that leakage would be there during full power operations. This is on a dual gasketed pump where it's not possible to check for leakage while at power. I've done the Google search, and read through all the information I have on hand, so I'd appreciate any leads.
Thanks much
Does anyone know how cooling down a system (dropping both temperature and pressure) affects leakage through gaskets as compared to full power operation? My practical experience is that when a system is heating up, minor gasket leakage tends to disappear and generally does not reappear. However, I haven't been able to find anything about minor leakage that shows up during shutdowns - if that leakage would be there during full power operations. This is on a dual gasketed pump where it's not possible to check for leakage while at power. I've done the Google search, and read through all the information I have on hand, so I'd appreciate any leads.
Thanks much
Patricia Lougheed
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RE: Minor Gasket Leakage During Cooldowns
Hope this Helps.
saxon
RE: Minor Gasket Leakage During Cooldowns
saxon
RE: Minor Gasket Leakage During Cooldowns
RE: Minor Gasket Leakage During Cooldowns
RE: Minor Gasket Leakage During Cooldowns
RE: Minor Gasket Leakage During Cooldowns
If you use a "soft seating" spiral wound gasket, and install it correctly so the flanges are squeezing against the outer guide ring, you have a rigid metal to metal joint. The thermal expansion of the system is taken up elsewhere- not by the gasket. Voila! the gaskets stay tight during operation, cool down and restart. Assembly torque values can be very misleading, so unless you know exactly what your friction factor is, you may have difficulty knowing if you have compressed the gasket all the way down to the guide ring. Take a look at a used spiral wound gasket. If it was installed corretly, you should see marks from the flange raised face biting into the guide ring all the way around it on both sides.
There are BIG differences between spiral wound gaskets. Make sure you specify and receive a low stress design.