Abstract: In order to improve the impact resistance and stability of the hydraulic supports, a new type of double-stage safety valve combined with a first-stage direct-acting valve with rated flow and pressure of 50 L/min and 45 MPa respectively and a second-stage differential valve with rated flow and pressure of 1000 L/min and 50 MPa respectively was designed. Moreover, a rapid dynamic load impact test system was developed based on the accumulator group, and the pressure dynamic response characteristics of the rapid dynamic load impact test system and the pressure-flow dynamic response characteristics of the double-stage safety valve were obtained by using AMESim and Simulink combined-simulation technology. Finally, a rapid dynamic load impact test bench prototype was established to test the double-stage safety valves. The results show that the rated pressure and flow rate of the second-stage differential valve are about 49.2 MPa and 992 L/min respectively, the opening time is less than 3 ms, the pressure stabilization time is within 1315 ms, and the unloading time is less than 5 ms. The experiments verify that the designed double-stage safety valve has the characteristics of fast unloading speed and excellent impact resistance and the correctness of the rapid dynamic load impact test scheme.

Key words: hydraulic support, double-stage safety valve, AMESim and Simulink combined-simulation technology, rapid dynamic load impact test

摘要： 为提高液压支架的抗冲击性和稳定性，设计了一种额定流量、额定压力分别为50 L/min和45 MPa的一级直动阀与额定流量、额定压力分别为1000 L/min、50 MPa的二级差动阀相组合的新型双级安全阀。开发了基于蓄能器组的快速动载冲击试验系统，利用AMESim-Simulink联合仿真技术获得了快速动载冲击试验系统的压力动态响应特性和双级安全阀压力流量动态响应特性，研制了快速动载冲击试验台样机对双级安全阀进行了测试。结果表明，二级差动阀额定压力、额定流量分别约为49.2 MPa和992 L/min，开启时间小于3 ms，压力稳定时间在13～15 ms范围内，卸荷时间小于5 ms，验证了设计的双级安全阀具有卸荷速度快与抗冲击性能优良的特点及快速动载冲击试验方案的正确性。

关键词: 液压支架, 双级安全阀, AMESim-Simulink联合仿真技术, 快速动载冲击试验