力士乐回转液压系统的优化设计

Optimized Design of Rexroth Rotary Hydraulic System

针对大型矿用液压挖掘机回转机构启动冲击、制动停止瞬间加载总成反向旋转造成的回转机构断齿、断轴及力士乐A2FE回转液压马达油口连接板192中的补油单向阀损坏的故障现象,通过增设回转缓冲阀、压力变送器等液压元器件,优化回转传动系统的启制动特性,降低回转机构启制动时的冲击,延长其使用寿命。结果表明:相较于优化前的回转液压系统,在相同的齿侧间隙下,优化后的回转液压系统的回转减速机输出轴小齿轮启动至接触回转滚盘轮齿的时长由0.5 s延长至1 s,有效减小系统的启动冲击;制动停止瞬间,回转马达A、B口之间的最大压差由3.6 MPa降至2.0 MPa,抑制了制动摆尾现象,降低制动冲击,操纵舒适性显著提高;回转液压系统无故障工作时长由1000 h提高到5368 h。

In view of the fault phenomenon of damage to the rotary mechanism broken tooth,broken shaft and Rexroth A2FE rotary hydraulic motor oil port connection plate 192 caused by the start impact of the rotary mechanism of large mining hydraulic excavator and the reverse rotation of the brake stop instantaneous loading assembly,the starting and braking characteristics of the rotary transmission system were optimized by adding hydraulic components such as rotary buffer valve and pressure transmitter,to reduce the impact of the rotary mechanism when starting braking,and prolong its service life.The results show that compared with the rotary hydraulic system before optimization,the time between the starting of the output shaft pinion of the rotary reducer and the contact of the rotary roller wheel teeth of the optimized rotary hydraulic system is extended from 0.5 s to 1 s under the condition of the same tooth side clearance,which effectively reduces the starting impact of the system.At the moment of braking stop,the maximum pressure difference between ports A and B of the rotary motor is reduced from 3.6 MPa to 2.0 MPa,which suppresses the phenomenon of brake swing,reduces brake impact,and significantly improves handling comfort.The trouble-free operating time of the rotary hydraulic system is increased from 1000 h to 5368 h.