BRT549
Chemical
- Dec 27, 2002
- 115
Got a problem pump that is regularly breaking the seal faces. It's a vaneaxial pump used as a circulator on a vacuum evaporator in phosphoric acid service. 528 rpm, 27,000 gpm, 195F, 21 psi deltaP across the impeller. The current Flowserve seal gets broken about 5 times a year when the pump impeller chatters during water washes. The silicon carbide seal faces shatter, and since it isn't a split seal it takes about 12 to 20 hours of downtime to fix. A split seal should be replacable in less than 2 hours.
I'm trying to get our maintenance people to use a split seal, but they think the split seals are unreliable. It doesn't fix the root cause, which the pump manufacturer says is us running against a shutoff head pressure. However, the split seal manufacturer I want to use (John Crane 37FS) says this seal will tolerate vibration better since it has a rubber 'boot' that will isolate the seal faces. Usually after a mechanical seal breaks, the pump is otherwise in okay condition and just needs a new seal. Any comments on split seal robustness would be appreciated.
I'm trying to get our maintenance people to use a split seal, but they think the split seals are unreliable. It doesn't fix the root cause, which the pump manufacturer says is us running against a shutoff head pressure. However, the split seal manufacturer I want to use (John Crane 37FS) says this seal will tolerate vibration better since it has a rubber 'boot' that will isolate the seal faces. Usually after a mechanical seal breaks, the pump is otherwise in okay condition and just needs a new seal. Any comments on split seal robustness would be appreciated.