With the development of social science and technology, more and more industries have strict demands on clean vacuum, environmental protection, etc. to avoid the pollution of oil return and leakage, so the oil-free vacuum pump has developed rapidly. Because of the late start, many enterprise users’ impression of oil-free vacuum pump only stays in a few categories of claw vacuum pump and screw vacuum pump. In fact, oil-free vacuum pump involves more than these types.
Speaking of oil-free vacuum pump, the first mentioned is claw vacuum pump. It is a dry vacuum pump developed for the electronic semiconductor industry. It can meet the needs of clean vacuum, and has the effect of self opening and closing valves with high efficiency.
Oil free rotary vane vacuum pump and oil free piston vacuum pump (reciprocating pump). Although the common rotary vane vacuum pump and piston vacuum pump have oil medium in the pump cavity, they can also achieve oil-free operation by using self-lubricating materials and become oil-free vacuum pump. In addition, the diaphragm vacuum pump in the reciprocating pump is also oil-free.
Vacuum is an indispensable part of many laboratory processes, but the costs related to vacuum generation, such as process cost, user cost and environmental cost, have never been considered. Although technology has improved to provide smaller, cleaner, quieter options, few people can use it.
The vacuum pumps used in the laboratory can be divided into two main types: rotary vane vacuum pump (sometimes referred to as oil lubrication pump) and dry-type (oil-free) pump. They operate in different ways to create a vacuum and pump liquid. Centrifugal pump uses centrifugal force to push the fluid through the outlet. The metering pump (such as diaphragm pump, piston pump and injection pump) sucks the fluid into the chamber and pushes it through the outlet valve; the positive displacement pump uses bellows, piston, rotating convex angle and rotating blade to push the fluid through the chamber, leaving a vacuum, so as to attract more fluid.
Oil lubricated pumps have been around for decades, and oil-free diaphragm pumps have only recently been added. Although the price without oil pump is often one and a half to two times that of oil pump, the use without oil pump has many advantages and can greatly save the service life. First of all, no oil is used, so there is no oil pollution and no need to change or dispose of the oil. No oil pump can be made corrosion-resistant, so no regular maintenance is required.
Piston type vacuum pumps and compressors must be used with oil-free air. The oil-free feature of vacuum pump ensures low maintenance cost.
Piston vacuum pumps and compressors are used where oil-free air is required. The oil-free feature of vacuum pump ensures low maintenance cost. These pumps have a maximum capacity of 6 m3 / HR and can achieve a vacuum of 10 mbar (a). When used as compressors, their pressure is approximately 7 bar (g) maximum.
These oil-free piston vacuum pumps are used in light industry, medical industry, printing and instrument industry, plastics, food and packaging, electronics, chemistry and textile industry.