Bearing material 1

[Graybags]

Hi,

Currently designing a trunnion mounted ball valve for use on seawater. The trunnion locates in a blind hole in the bottom of the ball and is normally sleeved with a nylon bush. Due to the fact that this valve needs to be of a "fire safe" design (client is insistent on it!), i'm looking for an alternative bearing material that won't perish at 500 deg C +. The ball and trunnion are both aluminium bronze B148 C95800.

Thanks in advance.

Graham

 

[unclesyd]

Your biggest problem is the bushing will be in stagnant area, very very bad for most materials. Materials like Nitronic 60 are out.

I would give Ampco technical people a call as they have been in the business for a while.

I know of a Fero-TiC bushing being tried in similar service, so you might give these people a call.

http://www.ampcometal.com/row/index.htm

http://www.alloytechnology.com/alloybonded/index.html

 

[boo1]

if sleeved with nylon, the seal will no hold at 500 c.