Large-sized water turbine blade multi-shaft linkage numerical control machining method based on casting roughcast

Abstract

The invention discloses a large-sized water turbine blade multi-shaft linkage numerical control machining method based on a casting roughcast. The method comprises the steps: 1) carrying out a three-dimensional coordinate measurement on a water turbine blade roughcast by a large-sized coordinate measuring machine, carrying out a point cloud acquisition of the blade roughcast by a scanner; 2) according to three-dimensional coordinate data and point cloud data of the blade roughcast obtained in the step 1), processing the three-dimensional coordinate data and the point cloud data of the blade roughcast by a computer, and then generating a computer model of the blade roughcast entity; and 3) based on the computer model of the blade roughcast entity obtained in the step 2), machining the roughcast entity of the giant water turbine blade by a numerical control programming, planning tool paths, and performing a machine simulation cutting emulation. Through the method, the accurate computer model of the blade roughcast entity can be obtained, and the roughcast entity can be flexibly preprocessed; the tool path empty knives are fewer, and thus the machining efficiency is high; the cutter spacing is reliable, and thus the quality accident is reduced; and the cutting condition is good, and thus the effective utilization rate is high.

Description

technical field [0001] The invention relates to a numerical control machining method for a blade of a large water turbine, in particular to a multi-axis linkage numerical control machining method for a blade of a large water turbine based on a casting blank. Background technique [0002] The water turbine is the prime mover of hydroelectric power generation, and the quality of the runner blades of the water turbine has a huge impact on the safety, reliability and economical operation of the hydropower unit. The turbine runner blade is a very complex sculpture surface. In the manufacturing process of large and medium-sized units, the manufacturing process of "sand casting-grinding wheel shovel grinding-three-dimensional sample inspection" has been adopted for a long time, which cannot effectively guarantee the accuracy and manufacturing quality of the blade surface. The current multi-axis linkage CNC machining technology is a cutting-edge high-tech in today's mechanical proc...

AI Technical Summary

Problems solved by technology

The main disadvantages of this method are: the status of the blank in the area with large curvature and the convex-concave area of ​​the blade surface cannot be accurately grasped; the physical condition of the blank is greatly affected by human factors and technical conditions, and there is no way to obtain the blank entity

In the multi-axis linkage machining of giant blades, the generated tool positions can only be generated using the theoretical model as a reference. The operability of the tool positions is poor, and there are many empty tool positions, which affects the processing efficiency

[0005] 3) In the prior art, machine tool operators carry out sub-area processi