Welcome to video on the liquid silicone rubber injection molding process. Today, KRMOLD will briefly explain the five key steps in liquid silicone rubber injection molding.
Step 1: Preparing the Silicone Material:
First, the silicone elastomer is mixed with a catalyst (typically a platinum-based compound) to achieve the desired consistency and physical and chemical properties. Pigments may also be added to enhance aesthetics. Precise preparation at this stage is crucial for molding efficiency and final product quality, so manufacturers often utilize advanced mixing and metering techniques.
Step 2: Loading the Injection Molding Machine
The silicone material is loaded into a heated cartridge, where the temperature is regulated between 250°C and 300°C, turning the material into a viscous liquid. Precise heating control prevents material degradation and ensures a uniform melt is injected into the mold at consistent pressure.
Step 3: Molding Process
The liquid silicone is injected into a closed mold under high pressure, where it is typically cooled to accelerate solidification. This stage is crucial for capturing detail and requires precise mold design to ensure the product meets specifications.
Step 4: Cooling and Ejection
After injection, the silicone needs to cool and solidify to achieve its final properties and strength. After the part cools, it is ejected from the mold by an ejector mechanism, and excess material may need to be trimmed.
Step 5: Post-Processing
Post-processing includes trimming and deburring. It may also include additional curing or surface treatment to enhance performance or aesthetics, and quality inspection to ensure compliance with standards.
