Brief description of surface quality and inspection requirements for injection molding

Injection molding surface quality and inspection requirements

1The raw materials must be fully dried according to the process requirements, and there must be no water, otherwise there will be silver streaks on the surface after injection.

2 Injection temperature, pressure, time, etc. meet the requirements of the process parameter card. The injection speed should be strictly controlled. The excessively fast injection speed will result in poor adhesion between the coating and the substrate (the injection speed of the plated parts is controlled between 15% and 35%)

3 During the injection molding process, the release agent cannot be used, especially the release agent containing silicone oil, otherwise it will affect the adhesion of the coating;

4 After the middle stop, the material should be cleaned to avoid the brittleness of the injection product due to the degradation of the raw material in the screw due to excessive residence time;

5 The surface of the injection molded parts shall not be polished and polished to avoid affecting the adhesion of the coating to the substrate;

6 The operator must bring cotton clean gloves during the injection molding process to avoid contamination of the surface of the product after injection molding;

7 Internal stress control: The product is not allowed to have large internal stress, and internal stress should be tested after injection molding (using glacial acetic acid soaking method)

8 size control: length, assembly foot or assembly hole meets drawing and gage measurement requirements

Surface quality inspection requirements

The surface should be smooth and even, without any shortage of material, material, deformation, cracking, discoloration, no pitting on the surface, shrinkage, flow marks, silver lines, oil spots, scratches, and weld lines less than the limit sample.

Appearance quality requirements

The appearance quality is consistent with the seal sample, the tip part avoids sharp corners, flash edges, trimming chips; the edge is flat, no gap, roll mouth; the assembly foot has no deformation, lack of material, break, and the assembly hole has no flash, Defects such as gaps.

Packaging requirements

The packaging meets the standard requirements to avoid surface scratches.