Liquid silicone rubber injection molding, also known as injection molding, is a kind of injection and molding method.Injection molding method has the advantage of production speed, high efficiency, can realize automation operation, breed of design and color is much, can shape by Jane to numerous, can from big to small size, and precise in dimension and product upgrading, can into complex shape parts, liquid silicone rubber injection molding is suitable for mass production with complex shape product and processing field.

    Liquid silicone rubber injection molding process:

    Liquid silicone injection molding (injection) molding process can be roughly divided into the following 6 stages: mold closing, shooting glue, pressure preservation, cooling, mold opening, product out.In this process, the quality of liquid silicone injection is generally closely related to temperature, pressure and time. Among them, the temperature control can be improved by three stages: cylinder temperature, nozzle temperature and mold temperature.Nozzle temperature is usually slightly lower than the high temperature of the cylinder, the principle is to avoid liquid silica gel vulcanization in the nozzle forming blockage.Mold temperature is divided into three parts: heating, heat preservation and cooling.The mold temperature is determined by the vulcanization conditions of liquid silicone rubber, the size and structure of injection parts, performance requirements, and other process conditions (hot vulcanization temperature of liquid silicone rubber, injection speed and injection pressure, the time required by a single injection part, etc.).

    Liquid silicone rubber injection molding pressure control.Pressure control in injection molding is divided into plasticizing pressure and injection pressure, which directly affect the quality of injection parts.

    1, plasticizing pressure: silicone rubber injection machine (back pressure) using screw injection machine, screw top melt in the rotation of the backward pressure is called plasticizing pressure, also known as back pressure.This pressure can be adjusted by the relief valve in the hydraulic system.Increasing the plasticizing pressure will strengthen the shear action is proportional to the increase of hot vulcanized silicone rubber material temperature;And vice versa;

    2. Injection pressure (injection pressure)

    The injection pressure of liquid silicone rubber injection machine is calculated by the pressure applied to liquid silicone rubber at the top of plunger or screw.The role of injection pressure in injection molding is to overcome the flow resistance of silicone rubber material from the cylinder to the cavity, the rate of silicone mold filling and the compaction of silicone rubber.

    There are three aspects to measure good liquid silicone injection parts:

    I. Appearance quality of liquid silicone injection parts, including integrity, color and gloss.

    2. Accuracy between size and relative position, namely size accuracy and position accuracy.

    3. Mechanical properties, chemical properties and electrical properties corresponding to the application, namely, functionality.

    The new technology of liquid silicone rubber injection molding is not limited to: micro injection molding, high filling compound injection molding, water injection molding, mixed use of various special injection molding processes, foam injection molding, mold technology, simulation technology, etc.

    Good liquid silicone rubber products cannot be separated from standard processing, but also from high-quality liquid silicone raw materials. Only good processing technology and standard process are combined to measure the standard of silicone products.How much do you understand? Welcome to discuss with us at Zinca silica gel.