The surface of a sheet metal workpiece should be flat without any burrs, protrusions or cracks. For riveting parts, it is: riveting nuts, riveting screws, riveting nuts and pull riveting nuts, etc., after high pressure on the parts, the thread can not be deformed. After pressing riveting, the pressing riveting zone should not be deformed, the pulling height and wall thickness should be uniform, and the top should not have any burrs. The metal sheet metal processing of mechanical hand sheet metal processing is welding requirements.

1. The weld seam should be firm and uniform, and there should be no defects such as virtual welding, crack, welding through, notch and undercut.

2, the length and height of the weld should not exceed the permitted requirements of the sheet metal parts.

3, the solder joint length is 8— 12 mm, the distance between the two solder joints should be 200; 20 mm.

4. If there are special requirements for the solder joints on the drawings, they should be executed according to the drawings.

5. After welding, there should be no defects such as slag inclusion, porosity, welding bead, bump and so on. Some important parts also need to be welded to remove stress, so as to prevent deformation.