It is often to observe that a vacuum pump has some faults like oil mist or oil spitting. Do you know why that happens?
You may find oil mist
• When the vacuum pump is started after the maintenance is finished and new exhaust filter is just installed.
The observed oil mist comes from the gas inside the oil tank before maintenance. It will be exhausted in about one minute and it’s normal to find such oil mist. If the vacuum pump keeps generating oil mist after maintenance, you have to check
a. if the exhaust filter is properly installed;
b. if the sealing between the exhaust filter and pump body is correct.
In case it’s not an installation problem, you need to check the quality of seals of the pump and that of the new filter.
• When the vacuum pump operates a couple of days or weeks after the maintenance
The service life of an exhaust filter is 2000 hours or 3 months plus. Short working life is usually caused by exhaust filter or vacuum oil. If the surface of the filter is darkened or very dirty, the oil is the root cause. On the contrary, if it’s pretty clean, it means the filter element has quality problem.
• When the vacuum pump works more than 2000 hours or 3 months
It can be considered as normal and it’s the time to do maintenance again. However, it’s not recommended to maintain the pump when obvious oil mist is observed. A regular maintenance will help extend the lifespan of the vacuum pump.
Oil spitting problem is similar, but not the same.
The most possible reason is sealing problem caused by seals, O-rings or gaskets. Some other reasons could be: