1、分析说液压阀芯和阀体在使用时不断产生磨损，使得零件尺寸、形状和表面质量发生变化，液压阀中的平衡弹簧、阀芯及阀座，在长期变载荷下工作，产生疲劳及裂纹，造成弹簧、折断或阀座密封表面剥落、损坏。
Lift manufacturers and analysts say hydraulic spool valve in the use of the continuous generation of wear and tear, making the part size, shape and surface quality changes in the balance of the hydraulic valve springs, valve and valve seat, working in long-term variable loads, fatigue and crack, causing the spring, break or seating surface spalling damage.

2、介绍液压阀零件加工过程中残留的残余应力和使用过程中的外载荷应力，超过零件材料的屈服强度，零件产生变形，液压油中混有水分或酸性物质过多，使用较长时间后，腐蚀液压阀中的零件，使其丧失应有的精度。
After the introduction of hydraulic valve lifter manufacturers parts processing residual residual stress and use external load stress, the yield strength of the material than the parts, parts deformation, hydraulic oil mixed with too much water or acidic substances, the use of a longer time corrosion of hydraulic valve parts, due to the loss of precision.

3、升降机在液压阀制造或修理时，没有达到规定的技术要求，阀芯与阀套间液的径向力不平衡，最终使阀芯压向阀套内壁面出现卡紧现象。
When the hydraulic lift valve manufacture or repair, did not meet the technical requirements, the radial force of the valve spool suites liquid imbalance eventually appear clamping pressure spool valve comprising a wall to the phenomenon.