Medical transfer molding provides strict control of part tolerances and can fill hundreds of mold cavities with a single preform material. For short-term and high-volume production, this flexible manufacturing method supports complex shapes, thin-walled parts, and consistent dimensions. Generally, medical transfer molding is used to overmold metal or plastic inserts with silicone rubber.
The Rubber Group provides medical transfer molding services and has extensive expertise in rubber to metal bonding and rubber to plastic bonding. Because we also provide compression molding and injection molding, we can help you choose the right process for your application. Read on to learn more about transfer molding or request a quote for your next medical molding project.
How does transfer molding work?
When the pre-weighed uncured rubber material is put into a "tank" that is part of the mold, transfer molding begins. Then the mold is closed and the plunger compresses the material. When heated, the pressure forces the uncured rubber into the cavity of the mold through the gate. The mold remains closed during the curing process. After that, the mold is opened and the parts are taken out.
What are the advantages of transfer molding?
Since transfer molding uses a closed mold system, less rubber escapes from the cavity, so fewer burrs need to be removed. Transfer molding can also produce sharper edges to reduce the risk of rubber gasket leakage. Since the rubber enters the cavity at a temperature close to the curing temperature, the curing time and cycle time of transfer molding are also shorter than that of compression molding.
What are the disadvantages of transfer molding?
Transfer molding generates more waste than other forms of rubber molding. That's because it will produce a large transfer pad that cannot be reused. Compared with injection molding, transfer molding also has a longer production cycle.
When is the best choice for medical delivery molding?
Transfer molding is usually the best choice for small and complex parts that require tight dimensional tolerances. It is also used for the design of complex parts produced in small batches and molds with multiple cavities. Although injection molding is usually associated with mass production, transfer molds can also be used for mass production. (Where applicable, we also use some injection molds to produce parts with lower annual output.)
What are the applications of medical transfer molding?
Medical transfer molding is widely used for silicone overmolding, especially the handles of medical and surgical instruments. Transfer molding is also used to produce parts with details such as grooves or pockets, or parts that use logos for brand promotion. Other applications include lip seals and U-shaped cups, as well as rubber products that require a clearly defined surface to avoid leakage.
Who provides medical delivery molding services?
The Rubber Group provides medical transfer molding services, rubber to metal bonding, and rubber to plastic bonding. Benefits include flexible production operations, shorter cycle times, design assistance and material selection assistance. Ask us how to overmold elastomers such as medical silicone on stainless steel, aluminum or plastic inserts for surgical instruments. We can also use transfer molding for medical devices with complex functions.
To learn more about our capabilities, please contact us.