Low-pressure injection molding operates on the principles of Reaction Injection Molding (RIM) technology. This process involves accurately measuring two or more liquid components, mixing them under high pressure using a mixing head, and quickly injecting the mixture into a closed mold. Inside the mold, the mixed raw materials undergo a chemical reaction, leading to cross-linking and solidification, resulting in the formation of the desired plastic product.
The process of low-pressure injection molding involves several key steps:
- Storage: The raw materials used in the RIM process are typically stored as liquids in two pressurized vessels, maintained under specific temperature and pressure conditions.
- Metering and Mixing: The components are precisely measured using metering pumps and delivered to the mixing head, where they are uniformly combined.
- Mold Filling: The mixed materials are rapidly injected into the mold. This step requires the raw materials to have low viscosity to ensure the entire mold cavity is filled efficiently.
- Curing: Inside the mold, the mixture undergoes a chemical reaction, quickly solidifying to form the final product.
- Demolding and Post-Processing: Once cured, the product is removed from the mold and subjected to necessary post-processing steps, such as deburring, sanding, painting, or other finishing procedures.