大型挖掘机回油背压系统的优化设计

针对含有博世力士乐背压阀总成的大型挖掘机液压回油背压系统，存在液压油温偏高及液压油散热器使用 800~1 200 h后出现渗油的故障现象，通过在外部管路增设单向阀、节流阀等零部件，实现回油背压单向阀的控制腔内最高工作压力设定及液压油快速充放，降低单向阀开启压力超调量，避免故障现象的产生。经试验验证，该方案简单可行、成本低，已授权实用新型专利（CN216199383U），在某公司的中大型液压挖掘机上推广运用。

Optimal Design of Oil Return Back Pressure System for Large Excavator

For large excavator hydraulic oil return back pressure system containing Bosch rexroth back pressure valve assembly,hydraulic oil temperature is high and the hydraulic oil radiator occurs oil leakage failure phenomenon after it was used 800~1 200 h.To solve the problem,through adding components on the outside pipe,such as check valve,throttle valve,the maximum working pressure setting in oil return back pressure valve control cavity and fast charging and discharging of hydraulic oil were achieved.The opening pressure overshoot of the check valve was reduce to avoid the occurrence of faults.The experimental results show that the scheme is simple and feasible with low cost,and the utility model patent (CN216199383U) has been granted.It has been popularized and applied in medium and large hydraulic excavators of a company.