Solid silicone rubber parts are currently used in many industries. Silicone parts can now replace the material parts of the electronics industry and hardware and plastics. Its quality assurance and product quality have become the whole product. The key issue is that in the production process of silicone fittings manufacturers, the appearance and functional defects of the products are often caused by the processing problems of the products. How should the control of poor production of silicone products be controlled?
Causes of common defects in silicone rubber parts
1. The product has insufficient vulcanization time, the time is too short and the temperature is too low, the product is completely cured, and the product quality problems appear. The product is soft and has no rebound strength, and the surface is unfamiliar and the interior is not cooked.
2. Improper charging method, the air in the cavity is not easy to discharge. For molds with complex mold structures and dead angles, they should be evenly distributed in various positions of the cavity during discharge, resulting in the phenomenon that the silicone rubber parts are lacking in corners and lack of material.
3. Into the mold cavity is the improper pressure of the machine or the secondary exhaust, resulting in the product is not familiar with the drum and the edge of the explosion, etc., according to the product structure, for multi-color silicone products, the exhaust is compared It is important to grasp the timing too early and too late will not be good for the exhaust, but also bring other bad phenomena!
4. The vulcanization pressure is insufficient. The gas and vulcanized volatiles retained in the cavity cannot be discharged in time. The pressure should be increased appropriately. Especially in the production of coils, the pressure is too fast, the mold is fast, and the gas is too late to be discharged. Pressurize to slowly close the mold.
5, the problem of rubber compound, the material after mixing for too long or the environment is dry, resulting in the processing of silicone parts can not be formed and cured, there is air or moisture in the rubber or excessive mold release agent in the mold cavity and moisture surface Bad phenomenon, the vulcanization rate of the rubber is too fast, the internal volatiles are too late to precipitate, and it has hardened. The formula should be adjusted to improve the induction period of the compound.
6, the structure and design of the mold of the silicone parts manufacturers, such as the design of the silicone parts is not reasonable, there will often be several phenomena, such as the product's parting line and complexity, mold release efficiency and product quality and production processing is not smooth The problem is that for the structurally complex products, multi-inlay molds should be used, and the air trough can be added to the place where the air holes are likely to occur, and the upper template wall cavity should not be too deep.
7. The mold temperature is too high, and the rubber material is placed for too long, which causes the rubber material to be uncured at high temperature, so the rubber parts need to be estimated during the processing. Evaluation of the number of holes.