Liquid Silicone Rubber (LSR) Molding Services

Liquid Silicone Rubber (LSR) molding is a precision injection molding process used to produce flexible, high-performance elastomeric components with excellent durability, biocompatibility, and environmental resistance. In this process, two liquid silicone components are precisely metered, mixed, and injected into a heated mold, where the material cures into a solid rubber part that retains the exact shape of the cavity. The process is highly automated and repeatable, enabling consistent production of complex, tight-tolerance parts with superior surface quality and long-term performance.

Capabilities

  • High-precision LSR injection molding for flexible, durable, and biocompatible components requiring tight tolerances, consistent repeatability, and excellent elastomer performance
  • Full program support from concept to production, including DFM (Design for Manufacturability), tooling design, prototyping, process development, validation, and scalable production
  • Overmolding and multi-material molding capabilities for bonding silicone to thermoplastics and metal substrates in integrated assemblies
  • Molding of silicone materials with a wide hardness range (10 to 80 Shore A durometer) to support applications from ultra-soft sealing to firm structural elastomer components
  • LSR materials engineered for extreme performance, including wide operating temperature range (-58°F to 392°F), excellent elongation, and strong resistance to UV, ozone, and weathering for long-term outdoor use
  • Excellent electrical insulation properties for electronic, automotive, and industrial sealing and protection applications
  • High-performance sealing capability for environmental protection, including IP67 and NEMA 6-rated submerged and dust-tight applications
  • Multi-cavity tooling for scalable production of high-volume silicone components with consistent quality and repeatability
  • Secondary services include trimming, inspection and cosmetic finishing, packaging, assembly and integration, adhesive bonding, heat insertion, leak and functional testing for sealing applications, labeling, and validation/quality inspection
  • On-time delivery with JIT (Kanban) programs

Flexible & Durable Components

Silicone materials provide long-lasting flexibility and resistance to wear.

High Temperature Resistance

Performs reliably in extreme heat and demanding operating conditions.

Precision & Consistency

Advanced molding ensures tight tolerances and repeatable part quality.

Chemical & Environmental Resistance

Resistant to moisture, chemicals, and harsh environmental exposure.

Key Materials for LSR Molding

  • Standard Industrial LSR: General-purpose silicone rubber offering excellent flexibility, thermal stability, and chemical resistance; commonly used for seals, gaskets, and molded components in automotive, industrial, and consumer applications.
  • Medical-Grade LSR: Biocompatible silicone formulated for healthcare applications requiring regulatory compliance, sterilization capability, and long-term material stability; used in medical devices, seals, and wearable components.
  • Food-Grade LSR: FDA-compliant silicone designed for food and beverage contact applications; odorless, tasteless, and suitable for kitchenware, baby products, and food handling components.
  • High-Temperature LSR: Engineered for elevated heat environments with excellent thermal stability; used in automotive under-hood components, industrial sealing, and heat-exposed assemblies.
  • Optical / Transparent LSR: High-clarity silicone material with excellent light transmission and low haze; used for LED lighting components, lenses, light guides, and display applications.

Common LSR Molding Applications

  • Medical & Healthcare: Seals, gaskets, valve components, syringe parts, catheter components, respiratory device parts, and wearable medical device interfaces requiring biocompatibility and sterilization compatibility
  • Automotive & EV: O-rings, gaskets, sensor seals, connector seals, lighting seals, and vibration dampening components exposed to heat, fluids, and environmental stress
  • Aerospace: Seals, gaskets, vibration isolators, and environmental protection components for interior and exterior systems requiring extreme temperature stability
  • Consumer Products & Household: Kitchenware components, appliance seals, waterproof buttons, soft-touch grips, baby care products, and reusable household sealing components
  • Electronics & Electrical: Keypads, button covers, connector seals, insulating components, and protective housings for moisture and dust resistance
  • Toys & Baby Products: Soft-touch molded parts, pacifier components, teething products, and flexible safety parts requiring non-toxic, durable silicone materials

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