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

Abstract

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.

Investigation of the effect of abrasive belt constant force grinding based on mechanical decoupling tool system

“…Some related study has shown that the constant grinding force combined with the optimal process parameters is quite suitable for belt grinding of complex surfaces. 21,22,26,32 In the process of machining, the change of speed v s or v w does not adversely affect the surface of the workpiece while the change of F n will cause impact in the contact area, leaving large marks on the machined surface. The phenomenon of over- and under-cutting of the workpieces can also be avoided by a constant normal force.…”

“…The phenomenon of over- and under-cutting of the workpieces can also be avoided by a constant normal force. 21,26 In Figure 3, the comparison schematic of constant and non-constant force grinding is demonstrated. The little angle α represents the error between actual surface of workpiece and theoretical trajectory.…”

“…The concave (CCV), convex (CVX), and Y-offset errors of a blade that underwent CABP were, respectively, 36%–24% and 17% less than those of a blade that underwent traditional method without constant force control. Duan et al 26 investigated the belt grinding process with force control system for blade of aero-engine. The application of a force controller improves the form accuracy from ≥±0.12 to ≤±0.08 mm.…”

“…In Zhang et al 24 and Jinfeng Zhang et al’s 25 article, the contact force is coupled with the position of belt, and the contact force will change as the belt position varies. Duan et al 26 developed a flexible belt grinding mechanism, and the normal force in this grinding process can be adjusted through the movement of an actuator in this new grinding unit. As the contact force is coupled with the position of the belt, actuators and sensors were installed in each axis of the tool system to control and calculate the position of the belt.…”

A Study on the Machinability of Steels and Alloys to Develop Recommendations for Setting Tool Performance Characteristics and Belt Grinding Modes

“…Grinding and polishing with flexible-base abrasive tools are widely used processes in the aerospace, automotive, shipbuilding, bearing, tool, wood pulp, and paper industries [ 1 , 2 , 3 , 4 ]. During rough machining, these technological processes ensure the removal of significant stock allowances (up to 400 mm 3 /mm·s) [ 5 , 6 ].…”