If your business needs large parts, this isn’t a problem with RIM. Reaction injection molding, or RIM, is often turned to as a scalable means to produce unique inner and outer parts on a limited budget. Read more about the reaction injection process
How Large Parts Are Produced
The reason we make large parts better is our ability to minimize manufacturing steps and keep tooling costs low. The polyol and isocyanate liquids are kept in separate tanks before being sent through supply lines to a chamber connected to the top and bottom molding plate. This setup creates a closed circuit that is only broken when the molder initiates a shot from the dispensing machine at high pressure. The RIM manufacturing process for large parts continues as the low-temperature polyurethane mixture flows from the mix head to an aftermixer to the mold cavity. Next, the mold cavity’s temperature is decreased via water lines, which serves to finalize the polyurethane part’s shape.
Why Large Molded Parts Are Possible
The RIM manufacturing process for large parts is different from plastic injection molding for a number of reasons. While plastic injection molding offers some advantages for smaller parts, larger parts have distinct needs and, therefore, rely on different processes. One of the key advantages of the RIM process is the low viscosity of the material injected into the mold. The low pressure during injection allows for very large but complex parts, made from high quality, lower cost tooling.
Unlike traditional injection molding, which relies on melting thermoplastic materials, RIM involves the mixing of two liquid reactants.
These two chemicals generate a specific reaction when mixed and offer remarkable versatility when making useful products. Second, the chemical bonding strength of polyurethane foam offers greater durability when a product is complete, making parts and hardware much less likely to break.
Benefits of Large Molded Parts
Medical and healthcare device makers and more often turn to RIM-molded large parts for essential equipment. Another advantage of large polyurethane foam parts is that they can be made affordably in large quantities, unlike steel, composites, and aluminum. RIM-molded large parts also provide superior durability, scratch protection, temperature resistance, and other characteristics that competing materials cannot easily replicate.
Now that you’ve learned about the full RIM manufacturing process for large parts, we’d love to hear more from you. Send a message to our team here, or upload your CAD file here to get started!