| If you are involved in
vacuum filtration, have large air leaks, or just exhibiting these problems,
this is not unusual. In filtration or drying it is possible that a large portion of what you are drying off your samples is ending up
in the pump. Then you have two problems. Contamination of the pump and
generally rising oil levels inside the pump from the condensed material,
solvent, or water.
Contamination In Pump
1. You are contaminating your pump with your
wash material or what is drying of the filtered product. Some simple solutions are as
follows.
a. Change the oil frequently to eliminate contaminate.
b. Install a cold trap to remove condensable vapors from air stream.
Oil coming from exhaust port
2. You are operating at high pressures (not full vacuum) and are having high gas flows
and oil mist (smoke), pump gurgling and might be making a real fine oil mess
all around the pump. Depending on the pump buy generally oil sealed
pumps have very tight tolerances to make them achieve high vacuum numbers.
If you really don't need those vacuum numbers and are quite happy with 27"
Hg and the system is leaking all over the place then you pump will misbehave
some. This is normal, nature of the beast. There are some thing
you might try to help alleviate this problem...
a. Raise exhaust port using standard pipe fittings or quick disconnect
vacuum fittings.
b. Install a coalescing exhaust filter to stop oil from exiting pump.
HyVac exhaust filters are designed to stop oil mist which requires to a
minor degree a special filter. Not any old off the shelf filter will
do it. Our oil filters are rated at like 99.9% or something like that.
c. Clean up your pump and confirm that the oil mess was from exhaust port and not a leak from
the pumps shaft seal, O-rings or the housing gaskets. 3. Sometimes
with a wet vacuum system enough condensable vapors come across go into the
pump and then turn back into a liquid in the pump oil which then increases the
overall liquid level in the oil sump of the pump. There is an airspace
in these pump, but if we fill this up with other liquid, along with the
original oil, then the next time you go to start the pump, it sucks in a
large gulp of air but the air has no where to go and ends up pushing the oil
and extra liquid right out the exhaust port of the pump as the intake of air
displaces this volume. |
