Let’s go on from last article about discussing the common problems in the mold test.
6.Gate sticking: due to mechanical resistance in the sprue bushing, insufficient cooling or failure of the pulling bar, the gate sticks in the sprue bushing.
7.Poor demolding: due to excessive filling, poor mold release performance, etc., the plastic parts are difficult to demold or the plastic parts are deformed or broken after demolding, or the residual direction of the plastic parts does not meet the design requirements.
8.Warpage/deformation: due to poor mold release, insufficient cooling, insufficient strength of plastic parts, deformation of the mold, etc., causing shape distortion of the plastic part, the wall thickness is uneven, etc.
9.Crack: due to excessive stress in the plastic part, poor mold release, uneven cooling, poor plastic performance, poor design of plastic parts and other defects (such as deformation), etc., causing fine cracks on the surface of the plastic part and near the feed opening.
10.Black spots and black bars: due to the decomposition of plastics or flammable volatiles in the material, the air is decomposed and burned under high temperature and high pressure, and the combustion products are injected into the plastic cavity with the melting, and black spots, black stripes, or plastic parts are formed on the surface of the plastic parts.
These are all common test problems for injection molds.In order to avoid wasted time and trouble during mass production, it is necessary to patience to adjust and control various processing conditions, and find the best temperature and pressure conditions, to develop a standard test procedure.