一台ＺＬ５０装载机的转向阀因外壳有裂纹而漏油，由于外壳材料为铸铁，用胶粘和加热保温电焊修补裂纹均未能解决漏油问题。因该机采用转向机与转向阀一体的结构，即转向阀直接装在转向机下端，故决定将转向机与转向阀总成全都更换新件。更换转向机与转向阀总成后，试机时出现 A ZL50 loader steering valve due to shell cracks and leakage, the shell material is cast iron, with adhesive and heat insulation welding repair cracks are not able to solve the problem of oil spills. Because the machine adopts the structure of the steering machine and the steering valve, that is, the steering valve is directly mounted on the lower end of the steering machine, so it is decided that the steering gear and the steering valve assembly will all be replaced with new ones. Replace the steering and steering valve assembly, the test machine appears