The advent of molding techniques in the manufacturing industry has completely revolutionized the mass production processes. The concept of molding and the various conceptual variations has given birth to multifarious molding methods. One variation is the rubber injection molding process. Read More…

Leading Manufacturers
RD Rubber Technology Corporation
Santa Fe Springs, CA | 562-941-4800RD Rubber Technology Corp is an ISO 9001:2015 certified company. We offer injection, LIM and transfer molding, rubber to metal bonding, engineering support, tooling design and more. Our customers rely on us to give them the best possible production solutions for rubber molding. From aerospace to medical, consumer products to military applications we build trust by being responsive to your needs.

Britech Industries
Stuart, FL | 772-286-9278If you have a need custom rubber molding for products with a fast turnaround, Britech Industries is the company you need to call. We do molded, extruded and die cut rubber – of various products and in the colors and compounds you need.

Pierce-Roberts Rubber Co.
Trenton, NJ | 609-394-5245With more than a century of manufacturing experience, Pierce-Roberts Rubber Co. is your source for custom molded rubber products.

Accurate Products, Inc.
Chicago, IL | 800-782-7776Rubber molding is what we do best. We believe in offering our very best to all customers no matter how large or small. For over 65 years we have pushed the boundaries of what we do and continue to improve our products and customer service every day.

REDCO Rubber Engineering & Development Company
Carson City, NV | 800-733-2648REDCO Rubber Engineering & Development is your complete source for rubber molding products, including rubber rollers, die-cut gaskets, and custom rubber products to suit your application.

National Rubber Corp.
Canonsburg, PA | 866-672-8100National Rubber was founded in 1997 with the values of variety, consistency, quality, open communication, and timely delivery at its core.

Mason Rubber Co., Inc.
Trevose, PA | 215-355-3440Mason Rubber is a full-service organization assisting in the designing or reverse engineering of custom product to fulfill your production requirements.

Minnesota Rubber & Plastics
Minneapolis, MN | 1-800-927-1422Minnesota Rubber and Plastics (MRP) is a leader in material compound development and the manufacturing of custom elastomeric and thermoplastic components. With facilities across North America, Europe, and Asia, MRP collaborates with original equipment manufacturers to solve difficult sealing and component challenges across multiple markets. Capabilities include materials science and formulation, fully functional product prototyping, and operational excellence and supply chain consolidation.

Premier Seals Manufacturing
Akron, OH | 877-771-6766With over 30 years of experience in the rubber molding industry, we remain committed to offering the best of our time and energy to all customers no matter how large or small.

Kent Rubber Supply Co.
Grand Rapids, MI | 616-538-4970Kent Rubber Supply leverages our experience, innovation and continuous development to ensure our customers get the best products. We specialize in small to large batch production runs of molded rubber parts, allowing us to offer ultimate customization when it comes to a wide variety of specs. Our products vary in shapes, sizes and wall thicknesses in materials such as PVC and urethane. Both domestic and offshore services are available.

Aero Rubber Company, Inc.
Tinley Park, IL | 800-662-1009Aero Rubber is an ISO 9001:2015-registered, world-class manufacturer of molded rubber products, custom molded rubber and molded rubber goods.

Jet Rubber Company
Rootstown, OH | 330-325-1821Jet Rubber Company, employee-owned, offers custom molded rubber and rubber to metal components. They offer rubber molding in a wide array of standard rubber products as well as custom options for those more complex and difficult jobs.

Device Technologies, Inc.
Southborough, MA | 508-229-2000Spring-Fast Grommets with fusion bonded nylon & a polymer cushion prevent wire chafe & give you best in class performance, 49% install savings & a 9.5x efficiency improvement. The nylon clad metal substrate snaps on with finger pressure & self locks - eliminating adhesives & the old slow & costly gluing process. It is used widely used in across the OEM & contract manufacture sectors. ISO 9001:2015 & AS 9100-D. Collaborative product customization available. Request free samples on site.

The advent of molding techniques in the manufacturing industry has completely revolutionized the mass production processes. The concept of molding and the various conceptual variations has given birth to multifarious molding methods. One variation is the rubber injection molding process.
Rubber injection molding is derived from the parent technique of rubber molding. But it is different from rubber molding as it includes injecting the raw material into the cavity under pressure.
How Rubber Injection Molding Works
The process of rubber injection molding follows the basic technique of pressurizing the liquified raw material into the cavities etched on the mold plate through a nozzle. The raw material is in the form of uncured rubber or elastomers mixed in bulk. The raw material is fed to the hopper (a container in which raw material is filled before processing) from where it is further taken in measured quantities to be provided to the injection nozzle. This process is followed by the filling up of the runner as the liquified rubber traverses through sprue bushing. From here on, the sprue provides the uncured rubber into the mold cavity. After the mold is completely filled according to the measured limit, compression takes place. Lastly, after the compression process, the mold is opened and the rubber products are ejected into a container. The working principle of the rubber injection molding process can be summarized as:
Injection → Compression → Ejection

Benefits of Rubber Injection Molding
Following are some of the advantages of the rubber injection molding process:
- The process of rubber injection molding has a high repeatability factor.
- As the mold is firmly closed, this process can be employed to obtain complex geometric shapes of rubber products.
- This process produces an extremely low scrap production as compared to other molding processes.
- Before the uncured rubber is injected into the cavity, it is preheated in order to reduce its viscosity, so it can easily flow into the cavities.
- It has a reduced cycle time, therefore making it a relatively rapid process.
- It is one of the most suitable manufacturing processes for the mass production of medium to high precision rubber products.
Disadvantages of Rubber Injection Molding
Where on the one side rubber injection molding process has these valuable advantages, there are also some drawbacks associated with this process, which are given below:
- The first and foremost disadvantage of this process is that even though it offers the provision of complex-shaped rubber products, still there is a wide range of rubber products that cannot be produced using this process.
- As it is suitable for mass production, in the case of small-scale production it can be a little bit costly.
- The setup cost can also be a bit costly, while the lead time may be longer.
- A number of mold defects can occur under certain undesirable conditions, resulting in faulty rubber products.
Applications of Rubber Injection Molding
Rubber injection molding, similar to plastic injection molding, has a long list of applications in the mechanical, electrical, and polymer industry, a few of which are:
- Stoppers
- Seals
- Electrical Overmolding
- Isolators
- O-rings
- Hot-melt Adhesives
- Contact Adhesives
- Sealants and Binders