Abstract: High-speed broaching is being attached much importance in the manufacturing process because of the high surface quality of its products.As to the high-pressure and high-flow hydraulic system,the force at beginning and on the end of broaching is abrupt load,which will inevitably result pressure shocks and velocity fluctuations.As a result,dimensional accuracy and surface quality are affected.Based on the analysis of broaching load characteristics,the broaching process of the hydraulic system is simulated by using AMESim software.When high-speed broaching in the condition of abrupt load,the pressure change in the hydraulic cylinder inlet chamber is researched,and the speed and acceleration of main slide carriage are analyzed.Then optimization of the hydraulic system is proposed based on the simulation.The results show that the low-pressure accumulator can effectively reduce system pressure shock at boot;the use of load force feedback PID control,can effectively reduce the pressure impact and speed fluctuation when broaching starts and finishes.

Key words: high-speed broaching, load force, pressure impact, speed fluctuation