Comparison of Processes

Comparison of Molding Processes

Rubber Compression Molding

Da/Pro Rubber, Inc. offers compression molding of rubber compounds. Compression molding consists of a top and bottom plate mold that is machined to a custom configuration. An elastomer preform is added between the plates and the plates are compressed under heat and pressure for a specific amount of time. The Da/Pro process monitors variables closely and adjusts to compensate for variable differences during each cycle. After the elastomer is cured properly, the mold is opened, the part is removed; the mold cleaned and the cycle repeated.

Rubber Transfer Molding

Da/Pro Rubber, Inc. offers transfer molding of rubber compounds. Transfer molding consists of a mold cavity similar to a compression mold. In addition, the mold contains a transfer pot and a ram, where the rubber material is placed before compression. The mold cavity contains transfer holes, which connect to the transfer pot through sprues. During molding, the ram is compressed and compounded rubber material flows through the sprues into the mold cavity configuration. Similar to compression molding, the Da/Pro process monitors all variables and compensates for differences during each cycle. After the elastomer is cured properly, the mold cavity is opened, the part is removed, the sprue is removed, the transfer pot and mold cavity is cleaned, and the cycle is repeated.

Rubber Injection Molding

Da/Pro Rubber, Inc. offers liquid silicone rubber (LSR) injection molding. This type of molding is also called liquid injection molding (LIM). LIM is similar to transfer molding, but the rubber material is supplied on a continuous basis through an injection nozzle. The liquid rubber is mixed in line with the cutting agents and is injected into the mold cavity. Under heat and pressure, the rubber cures. The part is then ejected from the cavity and the molding. The tooling for this process is more precision than compression due to the low viscosity of the liquid silicone.

Plastic Injection Molding

Da/Pro NE offers plastic injection molding services. This is a manufacturing process used for making components from thermoplastic and TPE materials. The plastic material is injected at high pressure into a mold made from the inverse of the desired shape. Unlike thermoset materials such as silicone, the plastic bonds are formed as the material cools. Once the part is cooled, a mold release removes the parts.

Comparison Molding Process Table 

Each process has its advantages and disadvantages. Our experienced staff of engineers, chemists and sales team can answer all of your questions and concerns with any of your molding needs. Please contact us.