Efficient constant-pressure-difference intermittent rotation extrusion abrasive flow polishing method

Abstract

The invention relates to an efficient constant-pressure-difference intermittent rotation extrusion abrasive flow polishing method and belongs to the technical field of automatic polishing of large-size complex-curved-surface type part intermittent rotation extrusion abrasive flows which are high in surface quality uniformity requirement. The method comprises that a gear is driven by a hydraulic motor to be meshed with a negative-clearance rotation disc bearing to perform rotation grinding polishing, seal rings are arranged at all connected faces to achieve high-pressure abrasive static seal, easily abrasive seal rings are arranged at the rotation friction positions special high-pressure abrasive seal rings and high-pressure abrasive seals are arranged at the piston abrasive extrusion positions to achieve high-pressure abrasive dynamic seal, and finally, high-pressure abrasive intermittent rotation grinding and polishing are achieved. The 'over-polishing' and 'rounding' phenomena of traditional abrasive flow extrusion are prevented, efficient precise uniform polishing of complex curved surfaces of impellers, blades and the like high in pneumatic performance and surface uniformity is achieved, and the surface roughness Ra of various complex parts can be reduced below 0.8.

Description

technical field [0001] The invention relates to a high-efficiency constant pressure difference intermittent rotary extrusion abrasive flow polishing method, which belongs to the technical field of automatic polishing of intermittent rotary extrusion abrasive flow for large-scale complex curved surface parts with high surface quality requirements. Background technique [0002] Mechanical products with complex curved surfaces, such as aero-engine blisks, impellers, blades, thin-walled parts, pump valve bodies and elongated holes, need to be processed by ultra-finishing after grinding, milling, EDM or other special processing To achieve uniform, low roughness and smooth surface processing requirements on the surface of the workpiece to be processed. At present, enterprises mainly use whetstone or manual polishing process, while the traditional extrusion abrasive flow technology will produce "rounding" and "over-polishing", which greatly affects the uniformity of the product sur...

AI Technical Summary

Problems solved by technology

At present, enterprises mainly use whetstone or manual polishing process, while the traditional extrusion abrasive flow technology will produce "rounding" and "over-polishing", which greatly affects the uniformity of the product surface

This is mainly due to: (1) due to interference, complex trajectory, etc., rigid polishing tools such as grinding wheel heads or abrasive belts have low efficiency and high cost, and it is difficult to achieve efficient polishing of complex curved surfaces; (2) traditional "bore pass" When polishing complex curved surfaces with rotary extrusion abrasive flow and rotating parts, due to the existence of the pressure difference between the inlet and outlet, it is easy for the processed workpiece to remove more material when the pressure is high, and remove material when the pressure is lower. (3) The "suction" rotary abrasive flow processing controlled by the pump valve as the power source, compared with the hydraulic system as the extrusion abrasive flow processing method of the feeding transmission system, although due to its own pressure Low and there is no pressure difference in the process of fluid abrasive polishing, but the pressure it provides is small, the viscosity of the abrasive is low, and the abrasive grains are loose. When the grinding and polishing process reaches a certain stage, the processing effect is not obvious

[0003] The extrusion abrasive flow process is an efficient polishing method for complex curved surfaces such as the inner surface of the mold, small holes, and valve cavities. However, the traditional extrusion abrasive flow process used in enterprises is mainly used in air conditioners with low aerodynamic performance requirements. Impellers, hydraulic valve chambers, slender holes, etc. have little effect on parts that are "rounded" and "over-thrown"; and aeroengine impellers, blades, and high-physical-performance screws that require high aerodynamic performance. Surface uniformity requires consistent complex curved surfaces. Due to the unequal pressure difference between the inlet and outlet of the traditional extrusion abrasive flow during the abrasive extrusion process of the workpiece, an uneven pressure field is formed in the sealed cavity flowing through the processed workpiece, thus It is very easy to cause surface unevenness such as "over-throwing" and "rounding" on the surface of the processed workpiece at the inflow and outflow of abrasive extrusion, and rely on pump valve suction type loose low-viscosity rotating abrasive flow polishing to provide pressure Small, low viscosity abrasive grains, it is ideal for ultra-fine polishing, but not suitable for rough polishing, semi-fine polishing and fine polishing

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