The main purpose of stainless steel weldment grinding is to remove the solder joint, which is the previous process of polishing or electroplating. Generally, it is divided into three processes: rough grinding, semi-fine grinding and fine grinding, which have corresponding requirements for the surface roughness of workpiece.
1. Visual inspection shall be carried out for the workpieces transferred to the grinding process in the previous process, such as whether there is missing welding, welding penetration, uneven depth of welding points, too far away from the joint, partial depression, uneven butt joint, deep scratches, bruises, serious deformation and other defects that cannot be remedied in this process, if any, they shall be returned to the previous process for repair. If there is no such defect, enter the grinding process.
2.For rough grinding, use 600 # sandpaper to grind the workpiece back and forth on three sides. The goal of this process is to remove the welding spots left by the workpiece welding and the bumps in the previous process, so as to achieve the initial forming of the fillet of the welding joint. The horizontal and vertical surfaces are basically free of big scratches, bumps, and the surface is flat without scratching. Pay attention to the tilt angle of the belt machine and control the pressure of the belt machine on the workpiece during the grinding process, so as to avoid the deformation of the workpiece or other problems.
3.Semi fine grinding: use 800# abrasive belt to grind the three sides of the workpiece according to the method of grinding the workpiece back and forth in the front, mainly to correct the joints in the previous process and to further fine grind the marks after rough grinding. The marks left by the previous process shall be grinded repeatedly until the surface of the workpiece is free of scratches and basically becomes bright.
4.Fine grinding, using 1000 × abrasive belt is mainly to correct the fine lines in the previous process. The grinding method is the same as above. The goal of this process is that the joint between the grinding part and the ungrinded part of the workpiece disappears basically, and the surface of the workpiece is further bright. The workpiece after grinding through this process should be basically close to the mirror effect, and the surface roughness of the workpiece should be able to reach r0.1mm
5.Note on replacement of belt: Generally speaking, 600 × belt can grind 6-8 workpieces with a length of 1500mm, 800 × belt can grind 4-6 workpieces, 1000 × belt can grind 1-2 workpieces. The specific situation also depends on the welding points of workpieces, the pressure used for polishing, and the grinding method. In addition, it should be noted that the replacement of the belt must ensure that the belt can rotate smoothly on the sponge wheel, so as to achieve the purpose of grinding the workpiece evenly.
In the process of grinding, pay attention to the tilt angle of the belt machine, control the pressure of the belt machine on the workpiece and the grinding time, so as to avoid deformation of the workpiece or other problems.
At each grinding stage, it should be noted that no new scratches and bruises will be produced in the process, because such defects cannot be repaired in the subsequent process.