重型双缓冲液压凿岩机冲击无力问题试验
Experimental on Impact Powerless of Heavy Hydraulic Rock Drill with Double Damper System

针对某重型双缓冲凿岩机样机存在的冲击力、机体发热等问题，首先，采用应力波法对样机冲击能进行了测试；然后，对样机进行了综合性能试验，测试了冲击活塞前腔和后腔，换向阀左腔和右腔，以及双缓冲系统一级和二级缓冲腔的压力变化；最后，得到了冲击活塞运动规律，获取了缓冲活塞的平衡位置及缓冲系统的工作状态。试验结果认为，换向阀工作正常、缓冲活塞平衡位置合理，而冲击活塞的打击点滞后于换向完成点，进而导致了样机的冲击力及机体发热。基于此提出了缩短隔套长度的解决方案，并对改进后的样机进行了试验验证。验证结果表明，冲击力问题得到基本解决，机体发热问题得到缓解。综合性能试验方法为凿岩机故障排查提供了一种有效手段。
Comprehensive performance tests are conducted on a certain domestic heavy hydraulic rock drill with double damper system in order to find the reasons of powerless impact and airframe fever reasons. First, the impact energy is measured by the stress wave test, and the pressures of each chamber is monitored, including the piston’s front-chamber and rear-chamber, shuttle valve’s left-chamber and right chamber, damper system’s first-stage and second-stage chambers. Then, the impact piston’s moving law is derived according to the data, and the damper system’s working condition and damping piston’s equilibrium position are calculated based on the law. The results indicate that the shuttle valve work properly, the damping piston’s equilibrium position is reasonable, and the prototype’s impact powerless and airframe fever are caused by the lag hit. Finally, an improved method to shorten the bushing length is proposed to improve the rock drill’s property by eliminating the impact powerless and alleviating the airframe fever.The comprehensive performance test provides an effective means for rock drills’troubleshooting.