No, there is two kinds machine, one is compression molding machine for rubber and solid silicone, another is injection molding machine for liquid silicone rubber.

What is Vacuum Compression Molding machine of rubber or silicone?

What is Injection Molding Machine of liquid silicone rubber?

Molding Processing-Compression Molding VS Injection Molding

Both rubber and solid silicone is pressed by vacuum compression molding machine. It's like making bread. 

Firstly, to prepare the formula of materials (silicone and rubber). In this step, different formulations, different attributes, different application environment. Be sure to customize the appropriate formula according to customer requirements.For example,need high temperature resistance with food grade, silicone is better choice, if to need chemical resistant with high temperature resistance, viton is better choice.

Second, to mixing compounds by closing and opening mixing of rubber ( raw material, curing agent)components. In this step, special attention should be paid to the uniform mixing of material components. When the film is formed on the open mill, special attention should be paid to the repeated refining. On the one hand, the materials are fully mixed, on the other hand, the gas inside is fully discharged. Be responsible for the problems such as bubbles in products after vulcanization molding.

Third, to make preform of the mixed formula materials into flakes or circles and put them into the mold cavity of the mold. In this process, should pay special attention to the weight of the raw materials. If the weight of the raw materials is less, there will be a problem of glue shortage. If there are too many, the nozzle will be thicker and it is difficult to trim.

Fourth, to start vacuum molding processing, the vacuum curing molding of rubber or solid silicone is under high temperature around 180 degree C with curing time 180 or 600 seconds depends on part structure. In this process, vulcanization temperature and molding machine pressure setting is the key points, must be set according to the characteristics of the formula. If the temperature is too high, the product vulcanization molding speed, but the quality will be reduced.Once the molding process, such as temperature and time, is confirmed, the subsequent batch production must be strictly carried out to ensure the long-term stability of the quality of large orders

Fifth, to make demolding. Opening the mold and take out the rubber or silicone parts through a high-pressure air gun. In this Step, the temperature inside the mold is very high, about 250 degrees. It is very hot. Different shapes of rubber or silicone products, their mold design shape is different, of course, the curing time is also different.like o-ring, rubber gasket, silicone.grommet or others.In this step, special attention should be paid do not be scalded arms, the whole demoulding completed, must use a high-pressure air gun to clean the mold, and then put rubber, and then start a new round of production. This process directly affects the molding cycle of the product and the quality of the next mold.

Injection Molding of Liquid silicone rubber

Liquid silicone rubber belongs to silicone, but its material is liquid and flowing, so its name is liquid silicone rubber.

Liquid silicone rubber belongs to a category of silicone, but it is liquid, so its machine is different from that of solid silicone and rubber. The molding machine for liquid silicone rubber is a liquid injection machine.

Liquid silicone rubber, without manual feeding, is directly extracted from the liquid machine, injected into the mold directly, and then molded at high temperature. Therefore, the production process, equipment, mold and other requirements are higher.

Compared with solid silicone, the liquid silicone rubber is more expensive, not suitable for small orders, so it is generally large quantities, high value-added products with liquid silicone rubber like medical parts. Large volume, fast production efficiency, expensive materials, product price is still cheap, like baby accessories pacifier, bottle and so on. 

Melon is a professional leading OEM manufacturer of Custom compression molding of Rubber Parts, Silicone parts, Liquid Silicone Rubber (LSR) Single-Shot, Two-Shot, and Multi-Shot (LSR/Thermoplastics) injection molded components with services ranging from design support, material selection, prototyping, high volume injection molding and clean room hygienic injection molding for customers in the automotive,medical/healthcare, sanitary, consumer, mother and child care, and industrial markets.

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