单斗液压挖掘机作业的主要特征是外载变化剧烈、复合动作频繁,当挖掘阻力增大或减小时,工作速度就随之减小或增大。液压系统对上述特征适应性能的好坏,是评价整机性能优劣的一个重要方面。就液压系统 The main feature of the single bucket hydraulic excavator is that the external load changes drastically and the compound action is frequent. When the excavation resistance increases or decreases, the working speed decreases or increases. The ability of the hydraulic system to adapt to the above characteristics is an important aspect of evaluating the performance of the entire machine. On the hydraulic system