Repeat Seal Failures
Repeat Seal Failures
(OP)
Suction pressure is 335PSIG
Disch Pressure is 590PSIG
PT is about 155C
Its got a plan 11 on the inner seals with this little bitty seal cooler on there. Delta T right now is about 5 degrees, basically doing nothing. The outer seal has plan 52 on it. About every 4 months or so the seal fails.





RE: Repeat Seal Failures
RE: Repeat Seal Failures
RE: Repeat Seal Failures
RE: Repeat Seal Failures
None of the seal plans you list should include a seal cooler. The pictures show a Plan 21 rather than Plan 11. You did not provide any details about the seal design, configuration or materials of construction. The pictures show a few deficiencies. The seal pots are too small for this pump. We would require 5 gallon pots. The seal pots are too low. The bottom of the pot should be at least 18 inches above the shaft center-line to provide for good thermo-siphon. The seal coolers are too small for a Plan 21. With a product temperature of more than 300 °F, I would expect those coolers to lime up quickly (depending on your water quality). Even with larger coolers, this is too hot for our water system. We would use an air-fin cooler or convert to a plan 23 to reduce the load on the cooler.
You did not mention where the seal pots are vented to. This is rather high suction pressure. I assume that the seals are a pusher design rather than bellows. You did not describe what you see when you disassemble a failed seal.
If we had this pump in our plant, I would recommend a Plan 53, double pusher seal. I would install five gallon pots with cooling water coils. I would use a similar high temperature synthetic oil to the Royal Purple product that you are using. I would have a Plan 23 on the primary seal. I would review the seal materials of construction for compatibility with my product stream.
Johnny Pellin
RE: Repeat Seal Failures
RE: Repeat Seal Failures
You must reply to your own thread to continue the discussion. That is how it works here.
Johnny Pellin
RE: Repeat Seal Failures
RE: Repeat Seal Failures
Johnny Pellin