Domestic turbine blade manufacturing has long used sand casting, manual shovel grinding and three-dimensional prototype testing. In recent years, blade grinding after molding, reprocessing after molding and CNC machining after casting have been developed. The manual shovel grinding method not only has a harsh working environment, high labor intensity, and low efficiency, but also has poor blade surface quality, which reduces the efficiency of the turbine.
The five-axis linkage CNC milling process of blades mainly includes: surface modeling, tool position calculation, tool position interference inspection, blade measurement, automatic alignment adjustment and processing program preparation, process clamping, processing methods and tool system configuration, etc.
The blade CNC machining process flow is shown in Figure 1.
1. Blade profile measurement
Since the distribution of the machining allowance of the casting blank is inconsistent, a three-dimensional measuring machine is used to measure the three-dimensional profile of the blank, and a measurement method that is efficient and convenient for computer data acquisition and processing and benchmark transformation is selected to achieve the best clamping position with evenly distributed allowance.
2. Surface modeling
The three-dimensional profile of the blade is created based on the original data to meet the next step of generating the code program for CNC machining.
3. Calculation of tool position path
Based on the three-dimensional profile data after reading the blade shape, setting the machining profile, cutting parameters and tool data, the tool position trajectory is calculated.
4. Tool path simulation and tool interference inspection
According to the tool position trajectory, the graphics are simulated and processed on the computer, and the tool interference is checked to ensure safe operation during real machine processing.
5. Post-processing
Perform post-processing on the tool position trajectory to generate NC code processing programs for specific machine tools.
