HTV high-temperature vulcanized silicone rubber is a kind of silicone product, with excellent high and low-temperature resistance, ultraviolet resistance, radiation resistance, weather resistance, electrical insulation, high breathability, physiological inertia, low compression permanent deformation and fatigue resistance, etc.
Therefore, HTV high-temperature vulcanized silicone rubber is widely used in aviation, aerospace, electronics and electrical, light industry, machinery, construction, chemical industry, medicine, daily necessities, and other aspects, the following will give you a detailed explanation of the three high temperature vulcanized silicone rubber molding process.
According to the types of high-temperature liquid silicone rubber on the market at present, one is solid silicone and the other is liquid silicone. The molding of solid silicone can be divided into molding and extrusion molding, and liquid silicone is mostly injection molding.
Molding
Molding is also called hot pressing, that is, in the high-temperature mold add (double 25 or double 24) a silicone platinum vulcanizing agent of the compound through the plate vulcanizing machine pressure, high-temperature vulcanization molding.
The molding process is the production process of solid silica gel. The upper and lower two modules are combined, and a mold core is placed in the middle, so it is called the molding silicone rubber.
The main production process of molded silicone rubber products is the processing process of silicone rubber products formed by heating and pressurizing the silicone rubber raw materials in the closed mold cavity.
Usually, the silicone raw materials are evenly mixed into the mixing machine, and the mold is moved into the vulcanization molding machine.
Then the closed mold pressure, molding and curing or vulcanization, and then the release of silica gel products, this process is suitable for thermosetting materials processing.
The hardness of molded fumed silica gel is usually 30-70A (Shore hardness). In the process of rubber mixing products in the silica gel factory, the raw rubber is first added to the double roll rubber mixer or closed kneader.
Gradually added white carbon black, silicone oil, and other additives repeatedly refining. According to the different fillers and additives, the performance of silica gel is also different.
This process is relatively low cost, high yield, and widely used. It is used for monochrome silica gel products.
It can also be used in two-color and two-hardness products or multi-color and multi-hardness products, but the structure of the product is not flexible, or limited.
It can also be applied to plastic and metal packages, the same structure is not flexible, and the package has temperature requirements, the general requirement of the package to withstand 180 degrees Celsius without deformation.
The shape of the injection molding process determines the shape of the molded silicone products. Molded silicone products are the most widely used in the silicone industry at present.
Mainly used in the production of silicone industrial accessories, buttons, silicone gifts, silicone bracelets, silicone watches, key bags, mobile phone covers, silicone kitchenware, silicone mat, ice grid, cake mold, and so on.
Extrusion forming
Extrusion molding is just like we squeeze the toothpaste. The extrusion head is also the cross-section shape of the product and has a certain length. Under the action of force and temperature, the products out of the head have been vulcanized and formed.
The products formed by this process are generally strip-shaped, and the product section can be various. Such as rectangular strips, ring silicon tubes, and so on.
Extruded silica gel products are usually extruded by an extrusion machine silicone molding, is a continuous molding process, that can be suitable for double 24 sulfides solid silica gel or platinum sulfide agent catalytic liquid silica gel production and processing.
It is a process in which the HTV silicone rubber is continuously made into semi-finished products of different shapes under the interaction of the cylinder of the silicone extruder and the rotating screw.
It can be used to process silicone tubes, silicone wire, cable insulation sleeves, and other silicone products.
Injection molding
Injection molding process requirements of equipment silicone injection machine, press. Its silicone raw material is A two-component liquid viscous, its principle is to use the press A, and B components of the raw material by the 1:1 pressure into the injection machine cylinder mixing, and then through the static mixer to be fully mixed, injection tube after injection molding production.
The molding temperature of this extrusion process is relatively low, at 130 degrees can. It can be used for plastic wrap molding that is less resistant to high temperatures, which has advantages over solid hot pressing.
Liquid silicone machine is widely used in medicine, food, silicone pacifier, baby products, diving supplies, electrical insulation accessories, cable accessories, and other liquid silicone products. The above three are the common compression molding process of high-temperature vulcanized silicone rubbers.