What Is LSR Overmolding?
LSR overmolding is a manufacturing technique that enables the creation of complex components by combining two distinct materials. Unlike LSR 2-shot molding, where both materials are molded simultaneously in a single process, LSR overmolding involves molding liquid silicone rubber (LSR) over an existing substrate, such as a pre-molded part or a metal component. This method provides enhanced functionality and material integration, making it ideal for producing specialized and high-performance products.
LSR Overmolding Process
Our LSR overmolding is a precise, two-step process designed for optimal material integration:
Step One: The pre-formed plastic or metal substrate is carefully positioned into the cavity of a specialized LSR mold using robotic automation.
Step Two: The mold is closed, initiating the injection of LSR into the cavity. The silicone fills the designated areas around the substrate, forming a fully integrated LSR component.
Partnering with a seasoned manufacturer with deep expertise in both tooling and LSR overmolding is crucial. Understanding the distinct properties of LSRs compared to thermoplastics can be the key to a successful outcome.
At Milosilicone, we bring extensive experience and specialized knowledge, having produced billions of custom silicone rubber overmolded parts for clients worldwide. We excel in delivering outstanding quality, especially for large-volume orders, and we tailor our molding process and quality assurance protocols to meet your specific needs. Every element of the LSR overmolding and insert molding process can be customized to produce liquid silicone parts that match your exact specifications.
Overmolding vs. 2-Shot Molding
Both overmolding and 2-shot molding techniques are used to combine two different substrates into a single multi-material component.
In LSR overmolding, liquid silicone rubber (LSR) is molded over a pre-existing metal or plastic part, offering flexibility in substrate combinations and design.
In contrast, the 2-shot molding process involves molding both materials simultaneously within the same machine, utilizing cavity-to-cavity alignment. This ensures superior bonding and precise placement of each material, resulting in a seamless, integrated component.
Advantages of LSR Overmolding
LSR overmolding offers unique advantages by allowing manufacturers to integrate non-plastic substrates, such as steel, into the injection molding process—something not achievable through traditional methods. This makes LSR overmolding a versatile and cost-effective solution across various industries and applications.
Here are key benefits of LSR overmolding:
1. Dual Material Benefits: Overmolded components combine the strengths of both materials used, offering a balance of rigidity and flexibility, along with enhanced sealing and insulation properties.
2. Integration of Non-Plastic Substrates: LSR overmolding uniquely enables the incorporation of substrates beyond just thermoplastics and elastomers, expanding design possibilities and material options.
3. Cost and Time Efficiency: By molding silicone rubber directly onto a metal or plastic substrate, the process eliminates the need for secondary assembly steps, resulting in significant savings in both time and costs.
4. Enhanced Design Flexibility: Integrating silicone rubber into the design of plastic or metal components enhances their waterproof, airtight, and shock-resistant qualities, offering greater versatility in product development.
5. High-Quality Output: The precision and control inherent in LSR molding ensure that the resulting parts are of high quality, with secure bonds and reduced risk of seal displacement.
6.Durability and Longevity: The robust bonding between the LSR and the substrate creates components that are highly durable and resistant to wear, environmental factors, and chemical exposure. This ensures a longer lifespan for products, making them more reliable in demanding applications.
Applications of LSR Overmolding
Life Sciences
Liquid silicone rubber (LSR) is prized in the life sciences industry due to its exceptional biocompatibility, hypoallergenic nature, and lack of odor and taste. These attributes make it indispensable for medical applications, including respiratory devices, surgical instruments, wearable medical technology, IV components, and syringes, all of which require strict sterilization. The medical sector also benefits from LSR overmolding in the creation of ergonomic grips for stainless steel instruments and handheld medical devices, enhancing both functionality and comfort.
Automotive
In the automotive industry, LSR overmolding provides durable, temperature-resistant seals essential for engine components, headlights, and electrical connectors. These silicone rubber seals are crucial in protecting electrical systems from moisture and other environmental factors. Automotive manufacturers rely on LSR overmolding to integrate seals into connectors and various plastic parts, ensuring robust performance in demanding conditions.
Consumer Goods
LSR’s resistance to cleaning agents, water, and environmental stressors, coupled with its electrical insulation properties, makes it an ideal material for a broad range of consumer products. This includes showerheads, electronic devices, and dispensing valves. LSR overmolded components are widely used in consumer electronics, food and beverage dispensers, kitchenware, and personal care products, offering durability and safety across diverse applications.
Industrial and Specialized Applications
The industrial sector leverages LSR overmolding for its ability to withstand extreme temperatures and pressures, making it ideal for seals and gaskets in high-demand environments like water heaters and furnaces. The precision of LSR overmolding also makes it the preferred choice for components with tight tolerances, ensuring reliable and accurate performance in complex systems.
Tailored LSR Overmolding Solutions from Milosilicone
Partner with a trusted industry leader who understands the intricacies of LSR overmolding, including the distinct challenges of working with both LSR and thermoplastics. At Milosilicone, we have successfully produced billions of custom silicone rubber overmolded components for top-tier companies, including several in the Fortune 100 and Fortune 500.
Our expertise lies in maintaining rigorous quality control across large-scale production runs. We offer the flexibility to tailor our quality assurance processes to align with your specific needs, ensuring each part meets the highest standards.
Beyond quality assurance, we offer complete customization of the LSR overmolding and insert plastic molding processes to create liquid silicone parts that match your exact specifications. From cost-effective mold design and development to prototyping and beyond, Milosilicone is your partner for comprehensive LSR overmolding solutions. Contact us today to explore our full range of services.