摘要
在设计目前国内最大的装机质量达270 t大型矿用液压挖掘机的动臂液压控制系统中,动臂抬升时采用多泵(四台主泵)供油,再通过阀外合流的方法满足动臂的速度要求,针对在动臂下降时,由于机械构件质量大、惯性非常大,导致下降结束阶段压力冲击大、下降速度慢、工作效率低的问题,提出动臂下降时采用比例再生阀,用流量再生回路实现能量回收,减小压力冲击,加快下降速度,同时提高系统工作效率。对挖掘机进行试验研究,结果表明,挖掘机加载最大试验负载25 t时,所设计的液压控制系统可以完全满足动臂正常工作所需要的压力及速度要求,动臂下降采用流量再生回路后,动臂可以完全下降到位,下降时间由37 s缩短至18 s,速度明显加快,下降压力更平稳,且无明显的液压冲击,同时由于下降时无需液压泵供油,降低了系统能耗。通过试验,验证了挖掘机液压控制方案的正确性,为今后在国内设计和制造更大型的液压挖掘机积累了数据和经验。
During the course of designing the hydraulic control system of the boom, which is the largest domestic quality 270 t large hydraulic excavators, multi-pump（four pumps） for oil and incorporation outside the valve are adopted to meet speed requirements while the boom is uplifting. While the boom is declining, the weight of mechanical components and large inertia of declining lead to great pressure shocks at the last stage of declining, low declining speed and low efficiency. In order to solve the problem, flow regeneration circuit is adopted to realize energy recycle, reduce the pressure shock and make the speed faster through the use of regeneration valve and so improve the efficiency. The experimental research of the excavator indicates that the designed hydraulic control system with maximum test load 25 t can fully meet pressure and speed the boom needed at its normal work. The boom can be fully declined in place after flow regeneration circuit is adopted with the declining time shortened from 37 s to 18 s, speed clearly accelerated, pressure more stable, and no apparent hydraulic shock. At the same time the system energy consumption is reduced without hydraulic pump for oil supply. Through the test, the correctness of the hydraulic control system of the excavator gets verified. And importantly data and experience have been accumulated for the future design and manufacture of larger hydraulic excavators.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2013年第12期161-166,共6页
Journal of Mechanical Engineering
基金
山西省科技厅攻关计划资助项目(20100321025-02)
关键词
液压挖掘机
动臂
液压控制
再生回路
Hydraulic excavator Boom Hydraulic control Hydraulic regeneration circuit
