Sealing Efficiency

[ADNPD]

Hello,

I was wondering if a globe valve creates a better seal than a gate valve when the flowing element is a gas?
Also, are rounded seals better than flat faced seals?

ADNPD

 

[ADNPD]

Correction,

I was actually wondering if a ball valve creates a better seal than a gate valve when the flowing element is a gas.
Thanks

 

[DLANDISSR]

ANDPD:
Both Ball Valves and Globe Valves with resilient seals provide better sealing that Gate Valves. If you want a tight seal use resilient seals.

Metal to metal seals leak more readily than resilient seals.

One precaution about using soft seats they must be compatible with the chemicals and the temperatures. If a valve is closed and gas enters under high pressur the heat of compression can heat the seat beyond its capability.
Another consideration when using soft seats, in high pressur gas service, is extruding. Some sofe material will extrude or flow under pressure will cause the seat to fail.

Valve manufacturers have test their valves and give the contiditons of pressure and temperature under which they will operate satisfactorily.

 

[ADNPD]

DLANDISSR,

Thank you for your reply. It was very informative and helpful. If I wanted to use a gate valve are there any sealing elements which would be beneficial. Thank you.

ADNPD