Smoking Oil-Sealed Rotary Vane Pump Background
Katy Manning | May 28, 2015

Smoking Oil-Sealed Rotary Vane Pump

Smoking Oil-Sealed Rotary Vane Pump


Question: What is causing the “smoke” coming out of my oil-sealed rotary vane pump exhaust ?

Answer: A common complaint we hear about oil sealed rotary vane pumps is that they create a lot of “smoke” from the exhaust. What is commonly reported as “smoke” is often actually oil mist vapor. 

The oil in your rotary vane pump both lubricates the moving parts and seals the fine clearances in the pump. Oil has the benefit  of stopping air leakages inside of the pump, however the rigorous oil flow during operation creates an oil mist on the exhaust side of the pump.  An unusual increase in oil mist vapor can indicate that there is a vacuum leak in your system.

If you find an increase of oil mist emitting from your vane pumps, first check that the position of your gas ballast is closed. The gas ballast is designed to allow a vacuum leak into the pump to temporarily drive off moisture and condensables. If the gas ballast is left open for an extended period, the oil will eventually drain out completely and will need to be refilled.

After checking the gas ballast move up the vacuum line and check that all o-rings and seals are properly seated and that there are no leaks. You may need to helium leak check your vacuum system.

For more technical assistance on your vacuum pump give us a call or send us an email here .

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