Reaction Injection Molding (RIM) Services by KAIAO-RPRT

KAIAO specializes in low-volume Reaction Injection Molding (RIM) for large, complex and lightweight plastic parts. Two liquid reactive components are metered, mixed and injected at low pressure into an in-house-made mold, then cure into a solid part in seconds—bridging the gap between prototyping and full-scale injection molding without the cost of a steel production tool. We run RIM on our own floor in Shenzhen, with CMM/FARO inspection and global delivery on every order.

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Custom Reaction Injection Molding (RIM) Services

RIM is a low-pressure process for large, lightweight and geometrically complex plastic parts—ideal when a steel production tool is not justified. Because the two liquid components mix and cure inside a closed mold, you get design freedom that hard-tool injection molding cannot match.

Large-Part Molding: Enclosures and structural panels up to 2,000×1,200×1,000 mm that are too big or costly for standard injection molding.
Complex Geometries: Mixed wall thicknesses from 3–20 mm, ribs, bosses and undercuts in one shot—no sink marks, no distortion.
Superior Material Properties: High-strength, chemically resistant polyurethane parts with excellent strength-to-weight ratio.

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Key Advantages of Our RIM Molding Services

KAIAO optimizes the reaction injection molding workflow to deliver industrial-grade components that balance structural strength and financial efficiency:

● Exceptional Design Freedom: Ribs, bosses, curves and undercuts in a single part; wall thickness mixed from 3–20 mm with no sink marks.

● Cost-Efficiency at Low Volume: Aluminum or epoxy tooling instead of hardened steel keeps upfront cost low; economic for runs of 1–3,000 parts.

● Rapid Turnaround: Typical cure cycle 30–60 seconds per part; in-house mold design and making completed in about two weeks.

● Superior Part Properties: Excellent strength-to-weight ratio, dimensional stability, chemical resistance and wear resistance from cross-linked PU.

● Class-A Surface Finish: Parts can leave the mold with cosmetic Class-A surfaces, then go to painting, coating or texturing.

● Large-Part Capable: Single shots up to 2,000×1,200×1,000 mm, holding rigidity even at thin walls.

● One-Roof Solution: From low-cost mold design and making to molding and finishing, all handled in-house for tight quality control.

Kaiao-RPRT's RIM Capabilities

Our comprehensive RIM capabilities are designed to meet diverse product requirements:

● Part Sizing: Large footprints in a single shot; parts up to 2,000×1,200×1,000 mm.
● Wall Thickness Control: Variable walls from 3–20 mm in one part.
● Intricate Details: Elaborate surface detail, integrated structures and tight tolerances.
● Insert Molding & Encapsulation: Low temperature and material adhesion allow inserts and encapsulation of components.
● Mold Design & Manufacturing: In-house molds from ABS, epoxy and aluminium, with fast turnaround.
● Simulation & Analysis: CAE simulation of cavity filling, curing, warpage and fiber orientation before cutting steel.

Materials Used in Kaiao-RPRT RIM

Kaiao-RPRT utilizes a range of advanced polyurethane (PU) materials, offering customizable properties to suit specific application needs:

● Standard Polyurethane (PU): Economical and versatile—high tensile strength, elasticity, durability and weather fastness; easily coloured, painted or textured.
● Glass Fiber Reinforced (GFR) RIM PU: Higher mechanical strength and impact resistance for structural and automotive parts.
● Integral Skin Foam (Self-Skinning Foam): Soft lightweight core with a firm durable skin—comfort, safety and shock absorption in one part.
● Other Thermosets: Structural foams and elastomeric polymers for specific properties on request.

Applications of RIM

RIM serves far more sectors than the seven below—these are representative rather than exhaustive, and most enquiries are for large, lightweight moulded parts. If your industry is not listed, send the drawing and we will confirm capability.

● Automotive: Body panels, bumpers, interior parts and EV charging enclosures.
● Medical & Scientific: Device housings and lab equipment needing chemical resistance or flammability ratings (e.g. UL94 V0), with EMC shielding options.
● Industrial & Agricultural Equipment: Enclosures, covers and structural parts where size, durability and chemical resistance matter.
● Consumer Goods: Appliance covers, electronics enclosures and furniture parts with fine surface detail.
● Marine: Dive units and marine parts requiring robustness and UV stability.
● Energy: Solar-canopy and infrastructure housings built for outdoor durability.
● Aerospace: Aircraft interior and lightweight structural components.

The Kaiao-RPRT RIM Process

Our streamlined RIM process ensures efficiency and precision from concept to completion

Consultation & Design Assistance

1. Engineers help optimise your design for RIM manufacturability (DFM), with an NDA signed before files are opened.

Mold Design & Manufacturing

2. Mold Design & Manufacturing: Low-cost molds designed and cut in-house from ABS, epoxy or aluminium, typically within two weeks.

Material Preparation & Injection

3. Material Prep & Injection: Two liquid components are metered, mixed in the head and injected at low pressure into the heated mold.

Curing & Demolding

4. Curing & Demolding: The mix reacts and solidifies in the mold, then the part is demolded.

Post-Processing & Finishing

5. Post-Processing & Finishing: Trimming, painting, coating, texturing or EMI shielding to final spec.

Quality Control & Delivery

6. Inspection & Shipping: Every part is measured (CMM/FARO) and packed for global delivery (DHL/FedEx/UPS).

Beyond Molding: Value-Added Services

Kaiao-RPRT offers comprehensive support beyond molding to deliver complete solutions:

● Product Design Assistance: Collaborating with you to optimize designs for manufacturability via RIM.
● Tool Design and Manufacturing: In-house capability for rapid and cost-effective mold creation.
● Painting and Surface Coatings: Achieving desired aesthetics and protection with various finishing options.
● EMI Shielding: Providing solutions for electromagnetic interference shielding where required.
● Value-Added Assembly & Kitting: Offering assembly services and kitting for ready-to-use components.
● Logistics and Packaging: Ensuring safe and timely delivery of your finished products.
● Complete Project and Program Management: Managing your project from concept to final production, ensuring seamless execution.

+86-0755-29007982 | kaiao@cn-rp.com