Stellite Hardfaced Valve trim
Stellite Hardfaced Valve trim
(OP)
Hello,
Subject: stellite 6 trim on Gate valves
I'd like to know if galling prevention is better achieved on full stellite trim (wedge and seat area) or half stellite trim (seat only)for wedge type gate valves?
Thanks in advance
Rusty211167
Subject: stellite 6 trim on Gate valves
I'd like to know if galling prevention is better achieved on full stellite trim (wedge and seat area) or half stellite trim (seat only)for wedge type gate valves?
Thanks in advance
Rusty211167





RE: Stellite Hardfaced Valve trim
Whats the size and service? Full stellite overlay shall not done properly (especially for big sizes) will overheat the 'soft' wedges and then bent.
Nature of operation? Operates frequently, NO, NC?
Why do you need full stellite if: 1. Most of the time the wedge (non sealing area) not in contact with abbrasive medium (steam, cat cracker, etc.). 2. Wedge design supposedly prevent friction for non sealing area side against the seat.
If you are tyring to control the flow by Gate valve, then it would be different case. But then it is questionable why you choose such type for controlling flow function.
Unless you have solid case, manufacturers most likely is reluctant for full stellite overlay
Regards,
MR
Greenfield and Brownfield have one thing in common; Valve(s) is deemed to "run to fail" earlier shall compared to other equipments
RE: Stellite Hardfaced Valve trim
The spec does not define between full or half hard faced trim.
The valve supplier has offered full hard faced trim valves and my concern is whether that trim will cause galling.
I've read elsewhere that satellite 6 on satellite 6 is okay, just looking for confirmation.
RE: Stellite Hardfaced Valve trim
Shall in doubt, choose the part which easier to be repaired (or replaced). For instance wedge against welded in seat. Then logically speaking shall the wedge is stellite 6 then the welded seat supposed to be at least st. 6 or higher (st. 12, etc).
In addition to that, yes smaller wedge may often offered as full stellite. Some manufacturer prefer to apply stellite overlay in one go for relativy small valves.
Regards,
MR
Greenfield and Brownfield have one thing in common; Valve(s) is deemed to "run to fail" earlier shall compared to other equipments