What is Silicone Compression Molding?
Silicone compression molding is a traditional yet highly effective method for producing durable silicone parts. We use solid silicone rubber (not LSR) and press it into precision-machined molds under heat and pressure. This allows for excellent part integrity and reliable mechanical properties.
We make silicone parts using compression molding, pressing solid silicone (not LSR) into precision molds under heat and pressure. Silicone can be tricky to mold, but we have the experience to get tight tolerances, reduce waste, and deliver both prototypes and larger production runs on time. With us, you get reliable parts and a partner who knows the process inside out.
Silicone Compression Molding Capabilities & Options
Typical process capabilities for Silicone compression-molded parts are provided below for reference. Actual values may vary depending on material type, part geometry, dimensional tolerance, and surface finish requirements for specific applications.
| Parameter | Recommended Range |
|---|---|
| Max Part Size | 3000mm * 2500mm (118 inch * 98 inch) |
| Color Options | Pantone / Sample / Custom |
| Surface Finishes | Glossy / Semi-glossy / Matte / Textured Finish |
| Tolerances | ±0.2 ~ ±1.0 mm |
| Injection Molding Cost | ⭐⭐⭐☆☆ |
Silicone Compression Molding Step-by-Step
At our facility, we specialize in true compression molding for custom silicone parts — a process that combines simplicity, flexibility, and reliability. Unlike injection molding, compression molding uses pre-measured silicone blanks (often HCR) that are directly placed into the heated mold cavity.
- Material Preparation: High-consistency silicone rubber is cut and pre-formed to match the mold cavity size.
- Mold Loading: The material is carefully placed into the preheated mold cavity.
- Compression & Curing: The mold is closed, and pressure is applied Under heat and pressure, the silicone flows to fill the cavity and cures (vulcanizes) into its final shape.
- Demolding: After the set curing time, the mold is opened and the finished part is removed.
- Deflashing & Finishing: Any excess flash is trimmed, and additional post-curing can be applied if required.
Silicone Rubber Material Properties
| Property | Density | Tensile Strength | Flexural Strength | Impact Strength (Unnotched) | Heat Deflection Temp (0.45 MPa) |
|---|---|---|---|---|---|
| Value/Description | 1.02–1.05 g/cm³ | 40 -50 MPa | 60-70 MPa | 20 -30 kJ/m² | 90-100℃ |
- The above parameters represent the baseline performance of the materials. Actual application should be dynamically optimized based on specific working conditions.
Related Process
Advantages & Disadvantages of Silicone Compression Molding
Silicone Compression Molding Advantages
- Lower cost – Tooling is cheaper and can often be modified or reused.
- Faster turnaround – Shorter development cycles, enabling quick iterations and small-batch production.
- Simpler process – Requires less complex equipment, suitable for multiple silicone grades.
- Better appearance – No gates required, so parts are free of gate marks.
- High flexibility – Supports insert molding, fabric molding, and encapsulation.
- Wide material compatibility – Works with various silicone formulations without complicated material changes.
Silicone Compression Molding Disadvantages
- Not suitable for very large volumes – Less efficient than injection molding for mass production.
- Labor-intensive – Higher manual involvement increases part cost compared to injection molding.
- Flash formation – Parts often develop flash that must be trimmed; tooling design can reduce but not eliminate it.
- Longer demolding for complex parts – Mold plates must be removed before taking out the part, which can take significantly more time for intricate designs.
- Design limitations – Less suitable for very thin-walled or highly complex geometries compared to injection molding.
Applications of Compression Molded Silicone
Medical & Healthcare
- Silicone gaskets
- Mask components
- Sealing rings in diagnostic devices
Electronics & Electrical
- Silicone keypads
- Connector seals
- Heat-resistant insulators
Industrial Equipment
- Valve seals
- Shock-absorbing pads
- Dust-proof covers
Consumer Goods
- Baby products
- Kitchenware handles and grips
- Waterproof buttons
Jiangzhi Silicone Compression Molding Parts are Guaranteed
100% satisfaction: High-performance silicone rubber mouldings with excellent resilience, precise dimensions, and stable quality – your vision, expertly molded in silicone.
No, we only offer compression molding for solid silicone rubber. If you're unsure which silicone method fits your project, we’re happy to advise.
Compression molding is ideal for larger, simpler silicone parts and lower production volumes. Injection molding, on the other hand, is faster and better suited for producing complex, high-volume parts. However, for many low- to mid-volume applications, compression molding remains the more cost-effective option.
Improper mold alignment, insufficient venting, or excess material can cause flash. We control all molding parameters and provide post-molding trimming to ensure clean parts.
Tooling takes 2–4 weeks. Production time depends on part complexity and volume, usually 1–5 minutes per part cycle.
