What is PU-RIM Moulding?
PU Moulding (Polyurethane Moulding) involves mixing two reactive liquid components which are injected into a mould, expanding and curing to form a lightweight, highly durable part. When combined with Reaction Injection Moulding (RIM), this process offers increased design flexibility and efficiency, making it ideal for producing large or complex plastic parts.
At ID Mouldings, we specialise in PU Moulding and Reaction Injection Moulding (RIM)—ideal for producing custom polyurethane parts with high strength and low weight. These solutions are perfect for industries like automotive, aerospace, defence, industrial machinery, and consumer products, especially for low- to mid-volume production runs.
After placing an order with ID Mouldings, you can expect tooling lead-times to be typically two to three weeks. Our expected tool life is up to 1,000 shots; this is obviously dependent upon the component’s geometry and complexity. In addition to single cavity tools, ID Mouldings can also offer you multiple cavity and family moulds. All tooling has the potential for the over-moulding of metallic or composite support structures; the inclusion of threaded male/female inserts are also common practice with us.
To produce your mouldings or components, we have access to a wide variety of quality resin grades which vary according to the application or requirement of your product.
Advantages of PU-RIM at ID Mouldings
Durable & Lightweight Components
Fast Cycle Times & Lower Tooling Costs
Ideal for Prototypes & Low-Volume Production
Supports Inserts, Overmoulds & Fine Detail
Flexible Finish Options – coloured materials or sandblasting for painting
Industries and Applications
Automotive & Motorsport
Medical & Industrial Equipment
Aerospace & Discovery
Body panels, bumpers, wheel arch extensions
Dashboards and custom trim pieces
Lightweight structural enhancements
Shock-absorbing housings
Lightweight machine guards
Ergonomic tools and enclosures
Structural brackets, enclosures, and covers
Components with embedded inserts or complex geometries
Automotive & Motorsport
Body panels, bumpers, wheel arch extensions
Dashboards and custom trim pieces
Lightweight structural enhancements
Medical & Industrial Equipment
Shock-absorbing housings
Lightweight machine guards
Ergonomic tools and enclosures
Aerospace & Discovery
Structural brackets, enclosures, and covers
Components with embedded inserts or complex geometries
Not sure where to start, ask an expert
Why Choose ID Mouldings?
Over 6 years of production experience with polyurethane moulding
In-house support from concept to delivery
Solutions for low-volume production, custom tooling, and prototype development
Dedicated to UK-based manufacturing and reshoring support
Resin Grades
RIM Resin (Core Stocked Resins | Shore Hardness | Deflection Temperature | Flexural Modulus | Tensile Strength | Linear Shrinkage (25°C Cure) | High Impact | 55-65 D | 75°C | 635-775 MPa | 25-30 MPa | 1.27 mm/m |
|---|---|---|---|---|---|
Fire Retardant (UL 94V0) | 78-83 D | 90°C | 1300-1500 MPa | 35-40 MPa | 4 mm/m |
Structural (Carbon Filled) | 80-84 D | 105°C | 1700-1800 MPa | 28-33 MPa | < 2 mm/m |
Productions sizes / Quantities
Tooling Type | Tooling Shot Life | Typical Batch Volumes | Silicone | 40-50 | 5-20 |
|---|---|---|
GRP | 400-500 | 30-50 |
Machined Resin (Green) | 1000+ | 30-100 |
Aluminium | 5000+ | 100+ |
FAQS
RIM Moulding offers a low capital investment on tooling (including the ability to modify tooling cost effectively), a shorter lead-time to production compared to injection moulding, flexible batch production and a greater freedom with design again compared injection moulding.
Generally speaking, the Tooling will last anywhere between 500-1000 parts before needing to be refurbished or replaced. This is based on single impression tooling, however muti-cavity tooling will produce many more. We do have green tooling that has produced well over 2500 parts.
The resin tooling is easy to refurbish. Where needed we simply re-machine the surface to produce a close to new tool.
We are able to manufacture using Green Tooling (Resin Tooling board), Heated Aluminum Tooling, GRP, Silicone and Printed Ceramic Tooling. Each tooling type has it’s benefits and limitations.
Bringing Manufacturing to the UK
At ID Mouldings, we support businesses looking to bring manufacturing back home. Reshoring improves quality control, shortens lead times, and supports the local economy. Whether you’re refurbishing tools or switching to UK-based production, we make the transition seamless.
Faster Delivery & Reduced Lead Times
