Vacuum pump oil filtration and replacement

During the use of vacuum pump oil, some of the oil deteriorates due to oxidation, emulsification, and impurities from the outside. When the metamorphic components and impurities reach a certain degree, the color of the oil changes, and the viscosity and acid value increase. The insoluble resinous material is precipitated, resulting in an increase in the vapor pressure of the vacuum pump oil and deteriorating the performance. The pump oil cannot be used anymore and new pump oil must be replaced.

In order to prevent the dust in the pump oil and the sucked material from entering the pump chamber together with the pump oil, for certain processes, a continuous filter device should be provided during the operation of the pump. Dust, impurities, and contaminated oil sink into the bottom of the main tank and then pass through the return line to the auxiliary tank. After separation and precipitation, the emulsified oil, water, dust, and impurities sink into the bottom of the auxiliary tank and are regularly discharged by the discharge valve. The relatively clean oil It is filtered by a filter located in the upper middle of the auxiliary fuel tank and then fed into the oil separation chamber through the oil inlet pipe and then fed to the end cap and the pump chamber.

The filter element in the filter blocks mechanical contaminants as the oil passes. The pump oil is purified. A pressure gauge is often attached to the filter to indicate if the filter is clogged. When pressure increases, oil does not flow normally. That is, the filter is clogged and the filter element should be replaced or cleaned.

Rotary vane pumps generally check the amount of oil every week. The time interval between oil changes depends on the operating conditions. Generally, the oil needs to be replaced when the pump extreme pressure rises due to poor oil lubrication, oil decomposition, or too much contaminants.

When the pumped medium and oil discharged from the exhaust valve pass through the separate exhaust cap, gas and a part of the steam are discharged from the exhaust port. The valve and the pump are linked, that is, when the pump is operated, the valve is started, and the oil passage opening opens the inflation port. When the pump is stopped, the valve oil outlet is closed, and at the same time, the air inlet is opened. Atmosphere inflates from the air inlet to the pump chamber through the oil inlet tube to destroy the vacuum in the pump chamber, so that the pump oil cannot enter the pump chamber.