Vacuum pump oil filtration and replacement considerations
During the use of vacuum pump oil, some of the oil deteriorates due to oxidation, emulsification and external impurities. When the metamorphic components and impurities are too high, the color of the oil changes, the viscosity and acid value increase, and precipitation Insoluble resinous substance. The vapor pressure of the vacuum pump oil is increased and the performance is deteriorated. At this point, the pump oil cannot be used anymore and a new pump oil is required.
In order to prevent the dust and the pulling substance in the pump oil from entering the pump chamber together with the pump oil, for some processes, a continuous filtering 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 flow into the auxiliary tank through the return pipe to separate and precipitate. The emulsified oil, water, dust and impurities sink into the bottom of the auxiliary tank and are periodically discharged by the discharge valve. The relatively clean oil Then, it is filtered by a filter disposed in the upper part of the auxiliary oil tank, and then enters the oil separation chamber through the oil inlet pipe to supply the end cover and the pump chamber.
The filter element inside the filter blocks mechanical contaminants as the oil passes. The pump oil is purified. A pressure gauge is often attached to the filter to show if the filter is clogged. When the pressure increases, the oil does not flow normally. That is, the filter is clogged, and the filter should be replaced or cleaned.
The rotary vane pump generally checks the amount of oil every week. The time interval for oil change depends on the working conditions. Generally, when the pump pressure rises due to poor oil lubrication, oil decomposition or too much contaminants, it is necessary to change the oil.
When the pumped medium and oil discharged from the exhaust valve pass through the separate exhaust cap, the gas and a part of the steam are discharged from the exhaust port, and the valve is interlocked with the pump, that is, when the pump is working. The valve is activated. The oil port opens and the inflation port is closed. When the pump stops, the valve oil passage is closed, and the inflation port is opened, and the atmosphere is inflated from the air inlet through the oil inlet pipe to the pump chamber to destroy the vacuum in the pump chamber, so that the pump oil cannot enter the pump chamber.