At present, hydraulic valve has the deficiency of inadequate interchangeability and machining difficulty of unsymmetrical valve spool.
目前，液压阀存在互换性差、不对称阀芯的设计加工困难等不足。
2
Because of the high flow resistance and the poor flowing ability, the spool valves can't meet the requirements for high velocity or huge hydraulic equipment.
同时由于滑阀流动阻力大，通流能力小，不能满足高速或大型液压设备对流量的要求。
3
In jet oil hydraulicspool valves, the oil flows through a rush path because of the shape changing of the valve.