Silicone Mold Design And Production

The requirements for the planning and production of silicone molds are: accurate scale, smooth surface; reasonable structure, high production efficiency, easy to automate; simple production, high lifespan and low cost; planning meets process requirements and is economically reasonable.

The structural planning and parameter selection of the silicone mold must consider factors such as rigidity, guiding, unloading organization, positioning method, and gap size. The consumables on the mold should be replaced simply. With regard to plastic molds and die-casting molds, it is also necessary to consider a reasonable casting system, molten plastic or metal activity, and the orientation and direction of entering the cavity. In order to improve the yield and reduce the loss of runner casting, a multi-cavity mold can be used to complete a plurality of identical or different articles together in one mold. High-efficiency, high-precision, high-life molds should be used in mass production.

The stamping die should use multi-station progressive die, and the carbide die-level progressive die can be used to improve the life. In small batch production and new product trial production, simple molds with simple structure, fast production and low cost should be selected, such as combination die, sheet die, urethane rubber die, low melting alloy die, zinc alloy die, superplastic alloy die, etc. Molds have begun to use computer-aided planning (CAD), which is a computer-centric system to optimize the mold. This is the development direction of mold planning.

According to the structural features, the silicone mold is divided into a flat punching die and a cavity die with space. The punching die uses the dimensions of the punch and the die to collaborate accurately, and some even have no gaps. Other forging dies such as cold extrusion dies, die casting dies, powder metallurgy dies, plastic dies, rubber dies, etc. are attributed to the cavity mold for forming a three-dimensional shaped workpiece. The cavity mold has scale requirements in three directions of length, width and height, and the shape is disordered and difficult to manufacture. Mold production is generally produced in a single piece and in small batches. The production requirements are strict and accurate, and more sophisticated processing equipment and measuring equipment are used.

The plane blanking die can be initially formed by electric spark machining, and then the precision is improved by forming grinding and coordinate grinding. Forming grinding can be carried out using an optical projection curve grinder, or a surface grinder with a shrinking and grinding wheel structure, or a special surface grinding machine for grinding on a fine surface grinder. Coordinate grinding machines can be used for fine positioning of the mold to ensure fine hole diameter and hole pitch. It is also possible to grind any curved shape of the punch and the die by a computer numerical control (CNC) continuous track coordinate grinding machine. The cavity mold is mostly processed by copy milling, EDM and electrolytic machining. The combination of copy milling and numerical control and the addition of three-way flat head equipment in EDM can improve the processing quality of the cavity. The addition of gas-filled electrolysis in electrolytic processing can improve production efficiency.