Belt grinding process with force control system for blade of aero-engine

摘要

In abrasive belt grinding process for surface of blade, elasticity, deformation and abrasive belt wear are major factors affecting the machining stability, efficiency and quality. In order to improve the grinding process and realize optimal grinding, a new controllable and flexible belt grinding mechanism is designed and assembled in a special computer numerical control grinding machine, accompanied with a constant grinding force control system. Based on the analysis of proportional valve and cylinder system in this grinding mechanism, a mathematic model of normal grinding force is constructed. Afterward, a fuzzy proportional-integral-derivative control strategy is proposed to deal with the uncertainty and nonlinearity of this system. A Simulink model of force control process is developed, and the good performance is achieved according to the simulation result. Finally, several grinding experiments for an aero-engine fan blade are carried out. The measurements show that the proposed grinding process with fuzzy proportional-integral-derivative force controller enhances the machining stability and efficiency considerably. What is more, the machining qualities, such as surface roughness, form accuracy and consistency, are improved significantly. And all the grinding results satisfy the machining requirements in the manufacturing process of blade.