Hydraulic diaphragm metering pump in which the hydraulic system is very small. In general, oil is incompressible, but the compressibility of air is large, about 10,000 times that of oil, so even if there is a small amount of air in the system, its influence is very large.

Dissolved in the oil in the air, when the low pressure will escape, from the oil bubble, form the cavity phenomenon, in the high, in the role of pressure oil, the bubbles and was quickly break, sharply under compression, noise in the system, at the same time in the gas is compressed when suddenly let out a lot of heat, so as to cause local overheating and accelerated the oil temperature is high, make the hydraulic components and hydraulic oil damage. The compressibility of air can also lead to the failure of working organs to creep and so on, which undermines the stability of the work and sometimes produces vibration.

The way to prevent air from entering the hydraulic system is:

The suction and return tubing should be inserted below the oil level and sufficient depth;

In the system, all parts should be filled with oil fluid. The method is to install a one-way valve at the outlet of the hydraulic pump, and the back pressure valve is set on the return oil road.

The oil level of the oil tank should be as large as possible. The suction side and the oil side should be separated by partitions to achieve the purpose of eliminating the bubble.

Place the air hole at the top of the pipe and hydraulic cylinder, and the air should be released when starting.

Should maintain the good seal of the pipe joint, especially the pipe line, if the seal is not good, the air is sucked into the hydraulic system.