1. Appearance characteristics
Mechanical damage is the process damage caused by bumping damage, or blanking or cutting during valve transportation, transfer, lifting, stacking, etc., such as scratches and indentations on flange sealing surfaces of convex or flat seals. The disadvantages of the casting of the rising face and the flashing of the forging are not processed. When these shortcomings reach depth, they will also affect the quality and life of the valve.
2. Inspection methods
Visual inspection of the mechanical damage of the valve surface can be found, and the depth of the defect can be measured by the weld inspection gauge or depth gauge.
3. Identification of defects
Radial scratches, mechanical damage and defects in the inner flange of the flange surface of the convex or flat seal, and the two sides of the flanged sealing groove of the ring have shortcomings such as scratches and bumps, which will affect the valve method. The sealability of the blue is generally not allowed to exist. Flange non-seal, valve body and bonnet surface scratches and mechanical damage as long as the depth is within the margin, does not affect the overall quality of the valve, can be accepted according to qualified products. But for sharp scratches, smooth and smooth, avoid stress gathering.
