How to check the quality of blade welding?
In order to ensure the welding quality, the turning tool after welding shall be carefully inspected to find out the causes of defects and improve them. Before inspection, the turning tool shall be sandblasted or lightly ground to remove the solder and impurities adhering to the blade surface, and cleaned with kerosene. The inspection items and requirements are as follows:
1、 Check the weld strength: grind the back of a turning tool with a green silicon carbide grinding wheel, and check the thickness of the solder layer, which is required to be less than 0.15 mm. There shall be no air hole or insufficient solder at the bottom surface of the tool tip support, and the weld not filled with solder shall not be greater than 10% of the total weld length. If there are air holes, the blade will fall off during cutting.
2、 Check the position of the blade in the tool groove: if the blade is misaligned and sagged beyond the technical requirements, re weld it.
3、 Check the welding strength: use a wooden hammer or a copper hammer to knock the blade with medium force, or use a hammer I to knock the cutter bar with strong force. If the blade does not fall off from the cutter groove, it RCGT Insert is qualified. Check the welding strength of the blade, not necessarily one by one, but also by sampling.
4、 Check the flatness of the blade: if there are obvious pits on the blade, it indicates that the blade is overheated and deformed, and the new blade should be burned and re welded.
5、 Check for cracks: after the blade is cleaned with kerosene, if the blade has cracks, kerosene will penetrate into the cracks and black lines will appear, which can be observed with the naked eye. It can also be observed with a 10-40x magnifying glass.
To check blade cracks, color flaw detection method can also be used: a solution made of 65% kerosene, 30% transformer oil and 5% turpentine, with a little Sudan red added. Put the part of the turning tool blade in the solution for 10-15 minutes, wash it with clean water, apply VBMT Insert a layer of white clay (kaolin), bake it for 1000 minutes, and observe its surface. If there are cracks on the blade, the color of the solution will be exposed on the white clay, which can be seen with the naked eye. The cracked blade cannot be used and needs to be re welded.
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