先导阻尼对二通插装阀组合换向阀压力损失的影响

The Influence of Pilot Damping on Pressure Loss of Two-way Cartridge Valve Combination Reversing Valve

二通插装阀组合而成的功能阀在各类高压大流量系统中应用广泛。常用的O型机能三位四通换向功能阀由P型先导电磁阀+二通插装阀组合而成,有一种由O型先导电磁阀+二通插装阀组合而成的换向阀,不仅具有O型机能三位四通功能,同时在进油端还集成防反冲功能,在系统急停等情况下供油端已卸荷,因换向功能阀阀芯未来得及关闭到位,可有效防止液压缸压力油瞬间超大流量回流并经已卸荷的电磁溢流阀回油的情况。但这种换向功能阀在使用一段时间后出现回油压力异常增高的现象。本研究为了解异常现象的背后机理,首先通过介绍其详细工作原理,分析并定位了影响回油压力异常增高的几个可能因素,针对换向功能阀,基于AMESim软件仿真模拟不同先导阻尼孔径对插装阀压力损失的影响效果来复现故障,再通过现场试验,验证了分析结果,最后给出了设计细节方面的优化建议。

The function valve composed of two-way cartridge valves is widely used in various high-pressure and large-flow systems.O-type three-position four-way directional valve composed of P-type pilot directional valve + two-way cartridge valves is used commonly,while there is a directional valve composed of O-type pilot directional valve and two-way cartridge valves,which not only has reversing function of O-type three-position and four-way valve,but also integrated with anti-backlash function at the oil inlet,which can effectively prevent the problem that the oil of the cylinder instantly recoils the HPU through the unloaded relief valve caused by emergency stop of the system or other situations,because the valve core of the directional valve is not closed in time and the HPU has been unloaded.This kind of directional valve has been used in a large flow hydraulic system for a period of time,and suddenly the problem of abnormal increase of oil return back pressure occurs.In order to analyze the mechanism behind the fault,the detailed working principle is introduced first,and the possible factors affecting the abnormal increase of oil return back pressure are analyzed and located.Based on AMESim software,the influence of different pilot damping apertures on pressure loss is simulated,and the analysis results are verified by tests.Finally,suggestions on design details are given.