用户购买我公司的一台ＷＹ３２型液压挖掘机，在施工过程中出现斗杆液压缸工作乏力并伴有自然下垂现象，起初怀疑是液压缸内泄，更换活塞组合密封后，该现象仍然存在。经过压力测试，我们认为可能是由于组合阀组的阀芯内泄所致。为了进一步验证上述判断，将该阀组拆下清洗，使 The user purchased a WY32 hydraulic excavator of our company. During the construction process, the hydraulic cylinder of the arm appeared weak and accompanied by natural sagging phenomenon. At first, it was suspected that the hydraulic cylinder was drained. After changing the combination of the piston seal, the phenomenon still existed. After the stress test, we think it may be due to the combination of valve spool valve leakage caused. In order to further verify the above judgment, the valve group removed and cleaned