In order to ensure the quality of welding, the welded turning tool should be carefully inspected to find out the cause of the defect and improve it. Before inspection, the turning tool should be sandblasted or gently ground to remove the solder and impurities adhered to the blade surface, and cleaned with kerosene. The items and requirements to be inspected 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, the thickness is required to be less than 0.15 mm. There should be no pores and insufficient solder at the bottom of the tip support, and the weld that is not filled with solder should not be greater than 10% of the total length of the weld. If there are pores, the blade will fall off when cutting.

　　2. Check the position of the blade in the tool groove: if the blade is misaligned and sagging exceeds the technical conditions, it should be re-welded.

　　3. Check the welding strength: use a wooden hammer or copper hammer to hit the blade with medium force, or use an I hammer to hit the knife bar strongly, at this time the blade does not fall off the knife groove to qualify. Check the welding strength of the blade, not necessarily check each one, but also use the spot check method.

　　4. Check the flatness of the blade: If there is an obvious pit on the blade, it means 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 by kerosene, if the blade has cracks. Kerosene penetrates into the cracks and black lines appear, which can be observed with the naked eye. It can also be observed with a magnifying glass of 10-40 times.

　　To check for blade cracks, you can also use the color flaw detection method: use a solution of 65% kerosene, 30% transformer oil and 5% turpentine, and add a little Sudan red. Place the turning tool blade part in this solution 10-15 minute, then wash with water, apply a layer of white clay (kaolin), and observe its surface after drying, if there are cracks on the blade, the color of the solution will be revealed on the white clay, which can be seen with the naked eye. Cracked blades cannot use, need to be re-soldered.