Bellows seal YT
This is a 2001 model, retrofitted with the bellows seal kit after 2 seasons, now dripping too much again. VFD drive, 123. No excess purge at all. Very tight, hardly ever lets a fart. Runs like a top other than the seal drip. I just set the cavity pressure barely positive at 60 Hz.
The machine spends most of the time around 45Hz, so the question is, should I set the cavity pressure at that speed or wound up?
Any other ideas about the bellows seal would be appreciated.
Thanks to all...
God Bless the USA
i won't change the oil setting. are you running unloaded for lengthy periods?heat seems to affect the performance
We lost the bellows type seal on a YT after 3500+/- hours. Upon disassembly I found burnt or coked oil on and around the carbon. This unit spends most of its time running at low load, it does have the VSD.
When the seal was originally installed the shaft seal cavity pressure was set at 17 psi. That number came from somewhere, but I don't recall the source.
When we installed the new seal the shaft seal cavity pressure was set at 2 psi. Here's why; when you look at how the shaft seal cavity and pressure regulator are built you'll see that oil is fed into the cavity and the regulator controls the pressure on the outlet of the cavity. When the pressure is setting is high less oil flows, when it is set low more oil flows through the cavity thus providing more cooling to the seal surfaces.
The machine has run continuously for 2700 hours since the new bellows seal was installed with about 1 inch of oil accumulation in the catch bottle.
Don't know if any of this helps. I would appreciate you posting the condition of the seal itself when you get a look at it.
When the going gets weird, the weird turn pro. HST