The reason is the breakdown on the gear pump oil and oil (two)       

Hydraulic oil will gear pump skeleton oil seal breakdown and overflow, resulting in oil seal string. Gear pump oil will seriously affect the normal operation of the machine. The reason is roughly the following four aspects: today, Xiao Bian introduced second aspects.

2, gear pump and the installation quality of the main engine is not required

(1) the installation of gear pump and main engine can not meet the requirements

When the gear pump is installed on the main engine, the coaxial error is less than 0.05mm.

If the end of the transmission installation of spline shaft spline shaft of the rotary center of the beating of tolerance, the gear pump will bear radial force under high rotation speed, resulting in the breakdown of oil and oil on; especially the sleeve type CBZb gear pump, bearing the radial pressure will damage the sleeve size to compensate, the harm is far greater than the fixed gap type CBC gear pump.

(2) the installation gap between components is not required

Before and after the pump cover and the pump gear pump stop function, therefore, with the gap is not too big; the gear pump and the transmission of external spline spline shaft spline belonging to the transmission device, with the gap is too small, otherwise it will form the interference.

(3) the asbestos gasket between the end of the front cover of the gear pump and the end of the transmission assembly is too thick.

In the installation process, the clamping force of the 4 fixed bolts is inconsistent, resulting in the deflection of the pump, affecting the seal of oil seal. The assembly between the end faces of asbestos pad sealing glue, although sealing more reliable, but the maintenance to bring a lot of inconvenience, a use of asbestos pad can be added after gel. Change the gear pump or the variable speed pump, change the asbestos mat every time. It is suggested that 0.6~0.8mm be adopted to make the installation deviation of the pump smaller, and it can be used repeatedly, and vibration and noise can be reduced.

(4) spline shaft causes oil seal string

Because the gear pump shaft spline and the transmission shaft shaft spline effective contact length is shorter, and the gear pump transmission torque is certain. When the gear pump works, the spline bears a large torque and produces extrusion, wear and even rolling key, resulting in high temperature, resulting in the skeleton oil seal lip burn, aging, and then breakdown and string oil. Therefore, when choosing the gear pump, the main engine should check the strength of the gear pump spline, and ensure that there is enough effective contact length.