Reaction injection molding (RIM) is a rapid molding process for making unreinforced thermoset parts rapidly in an environment of low pressure and room temperature. It uses a simple resin injection system with two pressurized chambers. The tools can usually last for up to 100 shots, and molded components can be solid like an injection-molded ABS, PP, structural foam, or rubber.
X Rapid Technologies offers a one-stop rapid reaction injection molding service from rapid mold-making, parts machining, surface treatment, assembly, and packing to global shipping. With over a decade of experience, we are your trusted reaction injection molding partner to fulfill all your rapid molding needs.
· Cost-effective: low mold costs and assembly costs can be reduced.
· Products enjoy durable and long-lasting, good structural stability.
· Fast molding processes and shortened lead time.
· Suitable for small and medium-sized production, trial products, etc.
· Fewer design limitations. The wall thickness of parts is not limited. Different wall thicknesses can be used on the same part.
· Able to meet different requirements, various product density, hardness, and bending modulus can be adjusted as required.
Initially, the monomer or prepolymer is mixed in a liquid state with a metering pump at a certain ratio into the mixing head. After the mixture is injected into the mold, it reacts rapidly and is cross-linked and cured in the mold. Then, after demolding, the part is complete. Finally, the RIM parts will be post-finished. Nearly all surface treatments are available, including painting, plating, screen printing, hand transfer printing, etc.
1. Different raw materials. Reaction injection molding uses two polymers that react in the mold and cure at room temperature. Plastic injection molding uses thermoset material which must be hot before being injected into the mold and cured by heating instead of cooling.
2. Different processing environments. The machine temperatures of reaction injection molding are less extreme than that of plastic injection molding.
3. Different costs. The cost of reaction injection molding is much lower than that of plastic injection molding. The main reason is the low mold costs.
4. Different lead times. Reaction injection molding is a kind of rapid molding process because the molds can be ready within a few days. The time is much shorter than that of plastic injection molding.
5. Different product features. RIM parts are lighter and can be ununiform-walled. Plastic-injected parts must have uniform wall thickness.
6. Different product applications. Parts by reaction injection molding are usually used for prototyping or small or medium-volume products. The minimum order quantity of plastic injection molding is very high and it is just for mass production.
When you need a small batch of large-sized plastic parts with uneven wall thicknesses, rapid reaction injection molding is the most suitable manufacturing solution. The parts can be used as prototypes for testing in new product development, or for end-use products to be put on the market.
We produce large, light-weight,
and thin-walled complex items by rapid molding process
at a cost lower than mass production.
The wall thickness can vary from 4 mm to
30 mm within the same part without distortion.
Perfect, cost-effective low volume annual production from a few hundred to thousands of parts.
The material for RIM is called polyurethane, PU in short. It can be divided into three types. · Foamed PU. They can be soft foam and dense foam, which are used to make sound insulation covers, heat insulation layers, etc. · Micro-foaming PU. Its density is generally 0.6-0.7 kg/m³. They can be applied to thick-walled and high-strength products. · Non-foaming PU. The material performance is similar to PP or ABS with a density of about 1.1-1.2 kg/m³. They are suitable for various thin-walled shell products, with aging resistance, strong impact resistance, high cohesion, easy to load and unload, etc. X Rapid Technologies usually use HD RIM4210/1100 PU, YU-Heng RIM5236 PU, and AXSON RIM875/900 PU. The properties of RIM parts are usually ABS-like or PP-like. Let us know your needs, and we will help you choose the appropriate material.
The lead time is usually 7 to 30 days mainly depending on the quantities and finishings. X Rapid Technologies will calculate the expected lead time while quoting. If you have a tight time range, let us know.
We don’t have a minimum order quantity for RIM. However, if you only want a one-off prototype, RIM is not economical. CNC machining is a better choice.
Sure, you can use RIM to make prototype plastic parts. Instead of low volume production, it is a rapid prototype injection molding process to create plastic parts. In the automotive industry, for example, one test often requires hundreds of prototypes during rapid prototyping. In this case, RIM is more cost-effective and faster than traditional plastic injection molding.
You may notice that the material used for RIM and vacuum casting is both called PU. Their main difference is that the part sizes are different. RIM is used to make larger plastic enclosures for low-volume manufacturing, such as automotive bumpers, medical device cases, and large-sized robots. Vacuum casting is primarily used in low-volume manufacturing of relatively small plastic (ABS, PC, acrylic, etc.) and soft rubber components. For more detailed information, you can go to our blog.
Sure. Rapid tooling is also another rapid molding service we offer. For some special materials like carbon fiber, we will use vacuum infusion processing which also involves a rapid molding process.