What Is Transfer Molding and How Does It Work?

 

Have you heard of transfer molding? Along with compression, injection and liquid molding, it’s one of the most common types of molding processes used in the manufacturing industry. Manufacturing companies use transfer molding to produce a variety of parts and products in custom shapes. Transfer molding, however, is a unique molding process that’s distinguished from its counterparts. To learn more about transfer molding and how it works, keep reading.

Overview of Transfer Molding

Transfer molding is a molding process that involves the creation of a new part or product by filling a mold cavity with raw material. The raw material is injected into the mold cavity. After the raw material solidifies, it creates the casting. The casting is then ejected from the mold cavity, which is essentially the part or product.

How Transfer Molding Works

Although it sounds complex, transfer molding works in a simple way. It requires the use of a mold, a plunger-based injection machine and raw material. Different types of materials can be used for transfer molding, including rubber, polymers and plastics. With transfer molding, the plunger-based machine is connected to the mold so that it creates a sealed environment. The plunger-based machine then injects the raw material into the mold cavity. Once the mold cavity has been completely filled, the raw material is left to cool and solidify.

Benefits of Transfer Molding

Transfer molding offers several benefits. When compared to compression molding, for instance, it allows for higher tolerances. This is due to the fact that transfer molding uses more pressure than compression molding. Both types of molding processes involve the use of pressurized raw material. With compression molding and transfer molding, the raw material is pressurized as it’s injected into the mold cavity. Transfer molding, though, applies more pressure to the raw material, thereby allowing for higher dimensional tolerances.

Transfer molding is also fast. When compared to other molding processes, it takes less time to perform transfer molding. The raw material used in compression molding doesn’t have to be completely liquid; it can be semi-solid. The semi-solid raw material can be injected or otherwise forced into the mold cavity by the plunger. This makes transfer molding faster than many other molding processes, particularly those that only support liquified material.

There are also variations of transfer molding. Some of the different variations include resin transfer molding, vacuum-assisted resin transfer molding and micro transfer molding. There are nuances between these different variants. Nonetheless, they are all considered types of transfer molding.