NEWS



12

2023

-

07

Injection molding processing surface quality and inspection requirements

Author:


Injection molding processing surface quality and inspection requirements

(1) The raw materials must be fully dried according to the process requirements, and there can be no moisture, otherwise there will be silver lines on the surface after injection molding

(2) The injection temperature, pressure, time, etc. meet the requirements of the process parameter card, the injection speed should be strictly controlled, too fast injection speed will lead to poor adhesion between the coating and the matrix (the injection speed of the electroplated parts is controlled between 15%-35%)

(3) During the injection molding process, no release agent can be used, especially a release agent containing silicone oil, otherwise it will affect the adhesion of the coating;

(4) The material should be cleared after the intermediate shutdown to avoid the brittleness of the injection molded 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 between the plating layer and the matrix;

(6) In the process of injection molding, the operator must wear clean gloves made of cotton 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 detection should be carried out after injection molding (using glacial acetic acid immersion method)

(8) Size control: the length, assembly foot or assembly hole meet the drawing and inspection tool measurement requirements

Surface quality inspection requirements

The surface should be smooth and smooth, uniform color, no lack of material, material inclusion, deformation, cracking, discoloration and layering, no pockmarks on the surface, shrinkage, flow marks, silver lines, oil spots, scratches, welded lines less than the limit sample.

Appearance quality requirements

The appearance quality is consistent with the sealing sample, and the end part avoids sharp corners, flashing, trimming chips; Flat edges, no notches, rolls; No deformation, lack of material, fracture of the assembly foot; The assembly hole has no flashing, notch and other defects.

Packaging requirements

The packaging meets the requirements of the packaging standard to avoid surface scratches.