The final forming of aero-blades has always been the bottleneck technology in aero-engine manufacturing, and the research of blade automatic polishing technology can solve a series of problems caused by the manual polishing of domestic blades. At present, the technical difficulties of aero-engine blade polishing have the following main aspects:
(1) The surface processing allowance is uneven. The blade of the precision wrought titanium alloy compressor is generally used to locate the surface, then the processing of the tenon, this processing feature makes the tenon positioning for the surface polishing, because the datum conversion brings the surface processing allowance uneven. At the same time, the shape surface is affected by the residual stress, especially the compressor blades, the magnitude of deformation and the inlet and exhaust edge thickness of the blade is at the same magnitude, reaching 0.1mm above.
(2) The curvature radius of blade inlet and exhaust edge is very small. Small compressor blades may even reach the R 0.1mm level. This makes the blade inlet and exhaust edge in the grinding, we must use a very small contact force for grinding. In addition, the inlet and exhaust edge grinding, the edge heat dissipation conditions are not good, the blade into the exhaust edge easily produce ablation.
(3) The shape of the transfer arc is complex and has a small radius. In the process of blade shape design, the transition arc is formed by the smooth transitions of the runner type and the leaf body, the round angle is around 2mm, the curvature varies greatly, and the programming brings great difficulty. Whether using grinding wheel grinding or abrasive belt grinding, the grinding wheel or abrasive belt pressing wheel should be less than φ4mm, and the development difficulty and service life of the grinding wheel or abrasive belt pressing wheel are facing great challenges.
The company's comprehensive automatic aero-vane grinder has a profile grinding, constant pressure grinding and CNC grinding 3 kinds of processing methods, can be the blade and other complex freeform surface finishing. The data information of the blade model is measured by a coordinate measuring head, and the processing program is programmed automatically according to the measured information, the production efficiency is higher than the manual grinding, the machining precision and the processing efficiency are higher.
The gas turbine blade polishing machine and the large blade polishing machine can polish the refractory titanium alloy blades and improve the surface quality.