What are the technological processes of sheet metal bending?（two）

3. Workpiece surface treatment after bending, riveting and other processes are completed. Different plate surface treatment methods are different. After cold plate processing, surface electroplating is generally carried out. After electroplating, no spraying treatment is carried out. Phosphating treatment is adopted and spraying treatment is carried out after phosphating treatment. The surface of plating plate is cleaned, degreased and then sprayed. Stainless steel plate (with mirror panel, fog panel, wire drawing board) can be drawn before bending, without spraying, if needed spraying to be wooled; Aluminum plate generally adopts oxidation treatment, according to the different color of spraying to choose different oxidation background.

Commonly used are black and natural color oxidation; aluminium plate needs to be sprayed after chromate oxidation treatment spraying. Surface pretreatment can clean the surface, significantly improve the adhesion of the film, and can double the corrosion resistance of the film. The cleaning process first cleans the workpiece, first hangs the workpiece on the assembly line, first passes through the cleaning solution (alloy degreasing powder), then enters the clean water, secondly passes through the spray area, then passes through the drying area, finally takes the workpiece off the assembly line.

4. After surface pretreatment, it enters the spraying process. When the workpiece requires spraying after assembly, the teeth or some conductive holes need to be protected.

The tooth hole can be checked into the soft rubber rod or screwed into the screw. The high temperature tape should be used for conductive protection, and the positioning tooling should be made in large quantities for positioning protection, so that the inner part of the workpiece will not be sprayed when spraying, and the nut (flanging) hole can be seen on the outer surface of the workpiece will be protected by screw, so as to avoid the need of the nut (flanging) hole of the workpiece after spraying. Return teeth.

Some large batches of workpieces are also protected by tooling.

When the workpiece is not assembled for spraying, the areas that need not be sprayed are protected by high temperature resistant tape and paper to block some nut holes exposed outside by screw or high temperature resistant rubber. If the workpiece is sprayed on both sides, the nut (stud) holes should be protected by the same method; small workpieces should be sprayed with lead wires or paper clips, etc. after they run together; some workpieces have high surface requirements and need to be scraped before spraying; and some workpieces should be protected by special high-temperature stickers at the grounding points.

When spraying, the workpiece is first hung on the pipeline and the dust on the surface is blown away by the air pipe. Into the spraying area spraying, after spraying along the pipeline into the drying area, and finally take off the sprayed workpiece from the pipeline.

There are also two types of spraying, manual spraying and automatic spraying, so the tooling used is different.

5. After spraying, it enters the assembly process. Before assembly, it is necessary to tear off the protective stickers used in the original spraying to make sure that the thread holes in the parts are not sprayed with paint or powder. During the whole process, gloves should be worn to avoid dust attaching to the workpiece, and some workpieces should be blown clean by air gun.

VI. After assembly, it enters the packaging process. After inspection, the workpiece is packed in special packaging bags for protection. Some workpieces without special packaging are packed with bubble film. Before packaging, the bubble film should be cut to the size of the workpiece that can be packed, so as not to affect the processing speed by cutting one side of the package; large batches can be customized special cartons or bubble bags, rubber pads, pallets, wooden boxes, etc. After packing, put it into carton, and then affix the label of finished or semi-finished products on the carton.