Reaction Injection Molding RIM Large Automotive Parts Rapid Prototyping To Low Volume Production
Reaction Injection Molding (RIM) is an innovative manufacturing process used to produce the large and complex plastic parts with high flexibility, strength and durability. RIM involves the mixing of liquid bi-component polyurethanes in a mixer at certain amount ratio, then injecting the liquid mixture at room temperature and low pressure into mold cavity where the mixture reacts and cures into a solid part.
Reaction Injection Molding Process Steps:
Mixing: two liquid polyurethanes are mixed together in a mixer at certain amount ratio.
Injection: the mixed liquid polyurethanes are injected into mold cavity under low pressure and room temperature.
Reaction: The liquid mixture reacts and cures inside the mold cavity and forms a solid part.
Demolding: The solid part is manually taken out from the mold cavity.
The high pressures used cause the plastic to conform to the mold’s shape, thereby generating the part. Like metal die casting, custom plastic injection molding typically produces components that require little or no additional work. Reaction Injection Molding (RIM) is a specialized subset of the injection molding technique that chemically bonds two or more plastics into a polymer before they are introduced into the mold.
The fairly low viscosity of the bi-component polyurethanes delivers high flowability that allows for the low injection molding pressure as well as temperature, which brings the feasibility of low tooling performance. So our RIM toolings are mostly made of epoxy resin and silicone rubber (sometimes aluminum or ABS) instead of mold steel.
RIM Parts Design Considerations:
When designing parts for RIM production, it's important to consider factors such as size, structure, wall thickness, draft angles, and gating. RIM parts can be designed with complex geometries and intricate details, but it's important to ensure that the part design is manufacturable and the tooling favors the design.
The core advantage of our RIM process is the extremely competitive tooling cost, the disadvantage is the part price since costly material and surface finishing. Which means more big size of the part, more competitive the RIM tooling cost, this is why our RIM is very suitable for low volume manufacturing the large plastic parts, such as automobile bumpers, large housings, big covers, etc. Insert molding and overmolding are available for our RIM.
Industry Applications:
RIM is commonly used in the low volume manufacturing or prototyping of automotive, aerospace, medical devices, and consumer goods parts. Such as automotive bumpers & grills, body panels, interior components, aerospace ducting, large enclosures, big housings and medical covering shells.
Due to the low injection molding temperatures and pressures, RIM is well-suited for molding large parts with variable wall thickness and smooth surface finishes. We can also benefit from its relatively high turnover rate, which makes it proficient in handling low to middle volume production projects. In addition, RIM parts have high tensile strength, heat resistance, and good resistance to corrosive acids or solvents. However, prolonged exposure to sunlight can degrade polymer-based parts.
We are a professional supplier. We know what we are doing. We keep a very stable quality level for years. Thanks to our professional production and technical team, our qualified products rate is 99.75% and we are constantly improving it, we hope our clients can get what they paid for.
How does HONKIA compare to other suppliers on price?
Compared to other Chinese suppliers, we choose not to compete on price but to offer the high level of quality, rapid response, and professional results. That’s why some customers cooperate with us for many years, compared with the price, they need a reliable partner to avoid serious losses caused by annoying after-sales service or even the trouble of finding no one.
What if I am not completely satisfied with the parts I receive?
HONKIA will free remake or amend the returned parts that you are not completely satisfied, or refund the full arrived payment, though this is rarely happened in the past. Any disputes based on a subjective or unilateral determination shall be discussed and negotiated to reach a reasonable result. Our continuing business relies on earning your confidence in our ability to meet and exceed the reasonable expectations.
