In the Chair Mould production process, various causes h […]
In the Chair Mould production process, various causes have caused various defects of various products, and the following kinds of chair mould defects and solutions have been made:
1. Deformation: The product is deformed when it is out of the mould. There are mould temperature, material temperature, and high temperature when the product is out of the mould, insufficient holding time and residual stress. The product wall thickness and shrinkage are uneven, and the gate position is improper. Improper position of the ejector pin, the result of the sticking mould, etc. must be considered in the design.
2. Fracture: too much material or filler, too small and too small ejector pin, too fast top speed, too low material temperature, soft mould, too small gap, etc., the inserts with inserts are not enough for preheating. Will cause cracks. A few products have to be annealed to eliminate stress.
3. Wear: The drafting angle is too small, the demoulding is difficult, the verticality is not good, and there is processing residue in the wear, such as the burr at the corner of the cavity after the grinding machine, the roughness is too large, etc., it is easy to solve. The bubble temperature is too low, too high, the wall thickness is too wide or too thick, the water is too high, contains solvent or volatile matter, the pressure is too large, the exhaust is not smooth, and the injection cycle is too long, causing the plastic to decompose in the barrel.
4. Flashing edge: The clamping pressure is not enough for the injection pressure, the template is deformed, the closure is not tight, the temperature is too high, the core cavity gap is too large, and the position is offset.
5. Marking: The plastic is decomposed by overheating, the pressure is too low, the flow channel, the gate is too small and the position is improper, or the gate design is unreasonable, the spray occurs, and the plastic is not sufficiently dried. The temperature is too low to form ripples during filling. Weld marks are difficult to avoid when multiple cores are broken. Reasonable temperature and injection speed are adjusted. The gate and exhaust overflow position is designed to improve the appearance of the product.