Metal Bellows Ambient Crude Oil

[Aerohorn]

Does anyone have any experience, good or bad, that they can share with using a metal bellows type seal for ambient crude oil BB1 pump (~200psi discharge).

We had a seal failure which looks to be abrasive damage on the rotor carbon face. The current seal is a pusher type and the springs were not easily compressed after 8 months in service. We've changed to a hard vs hard configuration but I was thinking a metal bellows would help keep the faces together such that solids can't enter easily.

However, I'm getting mixed recommendations from different seal OEMs. Some say the metal bellows is likely to tear or clog. Others says metal bellows would be a good upgrade.

 

[flexibox]

Few questions to ask. Does the crude oil contain water or sand or both? If you have water then the VP of the oil changes and you may be experiencing vapourisation. If you have sand it is possible you have abrasive wear. I don't believe that a metal bellows will solve your problem. I would use an single seal with silicon vs silicon carbide with external spring. If you identify there is water present then you need to go dual pressurised seals.
Send some pics to see if what you are seeing is abrasive wear. Do the face show radial cracking on the face? If so that confirms vapourisation.

A drawing with full duty conditions may help too.

Await to hear back.