# Food Grade Liquid Silicone Pot Lid Gasket Heat Resistant Sealing Ring
Product Overview
Our Food Grade Liquid Silicone Pot Lid Gasket is a high-performance sealing component manufactured via injection molding of medical and food-contact approved liquid silicone rubber (LSR), designed to eliminate steam leakage, heat loss, and food contamination risks for household and commercial cooking vessels. Unlike traditional rubber, EPDM, or solid silicone gaskets, this LSR sealing ring features consistent material homogeneity, zero micro-porosity, and precision dimensional tolerance control within ±0.05mm, ensuring a perfect fit with glass, stainless steel, ceramic, and cast iron pot lids of standard and custom sizes.
Core selling points include 220°C continuous high-temperature resistance, non-stick properties against oil, starch, and acidic food residues, 10,000+ opening/closing cycle durability, and full compliance with global food contact safety regulations. The gasket is engineered with a optimized multi-lip sealing structure that retains elasticity even after prolonged exposure to high pressure, steam, and repeated dishwashing cycles, eliminating the need for frequent replacements common with low-cost gasket alternatives. It is suitable for both OEM pot lid manufacturing and end-user replacement for stockpots, pressure cookers, frying pans, rice cookers, and sous vide cooking lids.
Technical Specifications
Material Properties
ParameterStandard ValueTest Method
Base MaterialPlatinum-cured food grade liquid silicone rubber (LSR)ISO 10993
Food Contact ComplianceFDA 21 CFR 177.2600, EU 1935/2004, LFGB (Germany), GB 4806.11-2021 (China)Third-party food contact testing
Shore A Hardness30, 40, 50, 60 (customizable 20–70 Shore A)ASTM D2240
Material Purity≥99.9% (no plasticizers, BPA, phthalates, PVC, or heavy metals)ICP-MS heavy metal testing
BiocompatibilityNon-cytotoxic, non-irritating to skinISO 10993-5
Physical Performance
ParameterStandard ValueTest Method
Continuous Operating Temperature Range-40°C to 220°C (short-term resistance up to 250°C for 30 minutes)ASTM D1329
Tensile Strength≥7.5 MPaASTM D412
Elongation at Break≥550%ASTM D412
Tear Strength≥25 kN/mASTM D624
Compression Set (22h at 177°C)≤15%ASTM D395 Method B
Steam Aging Resistance (1000h at 121°C)Hardness change ≤3 Shore A, tensile strength retention ≥90%IEC 60335-2-15
Dishwasher Cycle Durability≥500 cycles (no deformation, discoloration, or seal failure)NSF/ANSI 51
Water Absorption Rate≤0.1%ASTM D570
Process Parameters
ParameterStandard ValueNote
Dimensional Tolerance±0.05mm for diameters ≤200mm; ±0.1mm for diameters >200mmSuitable for precision-fit lid grooves
Standard Inner Diameter Range100mm, 120mm, 140mm, 160mm, 180mm, 200mm, 220mm, 240mm, 260mm, 280mm, 300mmCustom sizes available for non-standard lids
Cross-Section ShapesRound (O-ring), rectangular, multi-lip, trapezoidalCustom profiles for specific lid groove designs
Surface FinishMatte or glossy (customizable)Matte finish reduces food residue adhesion
Color OptionsTransparent, white, black, red, blue (custom Pantone colors available)Food-grade color masterbatch, no migration
Product Advantages
1. Superior Food Safety and Non-Contamination Performance
Manufactured via platinum curing system without peroxide residues, this LSR gasket eliminates the risk of chemical leaching into food even during prolonged high-temperature cooking. It is tasteless and odorless, will not alter the flavor of delicate dishes such as soups, steamed seafood, or infant food, and is resistant to staining from curry, tomato sauce, soy sauce, and other pigmented foods, preventing cross-contamination between different meal preparations.
2. Extreme Temperature and Durability for Long Service Life
Unlike EPDM or nitrile rubber gaskets that harden and crack after 3–6 months of use, this LSR gasket retains over 90% of its original elasticity after 2 years of regular domestic use. Its 220°C heat resistance makes it suitable for oven use, pressure cooking (up to 2 bar operating pressure), and sous vide water bath cooking, while its low-temperature resistance down to -40°C allows for safe freezer storage of sealed food without gasket brittleness.
3. Reliable Sealing Performance to Reduce Energy Waste
The precision-molded multi-lip structure creates a 360° uniform seal between the lid and pot rim, reducing steam leakage by 98% compared to low-precision solid silicone gaskets. This cuts cooking time by 10–15% for boiled and steamed dishes, reduces gas/electricity consumption, and prevents hot steam burns caused by uneven steam escape. It also maintains a consistent internal pressure for pressure cookers and vacuum-sealed lids, eliminating pressure release failures that pose safety risks.
4. Low Maintenance and Wide Compatibility
The non-stick LSR surface requires only simple rinsing with warm soapy water to remove oil and food residues, and it is fully compatible with top and bottom dishwasher racks, microwave ovens, and sterilizers. It fits seamlessly with most standard lid brands on the market, and its inert material does not react with acidic, alkaline, or salty food ingredients, making it suitable for all cooking cuisines.
Applications
Household Cooking Vessels
- Replacement gaskets for stockpot lids, glass frying pan lids, ceramic casserole lids, and cast iron Dutch oven lids, preventing heat loss and soup boiling over during daily cooking.
- Matching gaskets for electric pressure cookers, rice cookers, slow cookers, and multi-functional cooking pots, ensuring pressure stability and even heating for rice, stews, and braised dishes.
- Sealing components for sous vide lids and fermenter lids, maintaining a consistent internal temperature and preventing external contamination during low-temperature cooking and food fermentation.
Commercial Food Service
- Gaskets for commercial kitchen stockpots, steamer lids, and braising pan lids in restaurants, hotels, and catering businesses, withstanding 12+ hours of daily high-temperature use and frequent commercial dishwasher cleaning.
- Sealing rings for food storage container lids in central kitchens and food processing plants, maintaining food freshness during cold chain transport and preventing cross-contamination between different food batches.
- Matching components for baby food steamer lids and milk warmer lids, meeting the strictest food safety requirements for infant food preparation.
Specialized Cooking Scenarios
- Sealing gaskets for outdoor camping pot lids, withstanding extreme temperature fluctuations between high-altitude boiling and low-temperature outdoor storage without deformation.
- Gaskets for laboratory water bath pot lids and medical sterilizer lids, providing non-toxic, high-temperature resistant sealing for sterile testing and equipment sterilization processes.
Selection Guide
Hardness Selection
- 30–40 Shore A: Recommended for irregular or slightly worn lid grooves, and lids for glass containers that require low closing force. The softer material conforms to minor surface imperfections for a tight seal, and is ideal for household users who prefer easy lid opening and closing.
- 40–50 Shore A: Universal hardness for most household pot lids, pressure cookers, and rice cookers, balancing elasticity and compression resistance to maintain a reliable seal even under 2 bar pressure.
- 50–60 Shore A: Recommended for commercial cooking vessels and high-pressure industrial lids, with higher wear resistance to withstand frequent opening and closing cycles, suitable for 12+ hours of daily commercial use.
Size Specifications
- Measure the inner diameter of your lid’s existing gasket groove (not the outer diameter of the lid) to confirm the required gasket size. If your existing gasket is stretched or deformed, measure the diameter of the pot rim that the lid fits onto, and select a gasket with an inner diameter 1–2mm smaller than the measured pot rim diameter to ensure a tight fit.
- For custom sizes (diameters over 300mm or non-standard cross-section shapes), provide a sample of your existing gasket or a technical drawing of the lid groove to our engineering team for customized mold development, with a lead time of 7–10 working days for custom samples.
Material Grade
- Standard Food Grade: Meets FDA and EU 1935/2004 standards, suitable for general household and commercial cooking use, the most cost-effective option for most applications.
- LFGB-Grade: Passes Germany’s strict LFGB testing for volatile organic compound (VOC) and sensory requirements, recommended for infant food preparation, coffee machine lids, and applications involving contact with high-fat or acidic foods for prolonged periods.
- Medical Grade: Meets ISO 10993 biocompatibility standards, suitable for laboratory and medical sterilization equipment lids requiring zero cytotoxicity.
Quality Assurance
All our Food Grade Liquid Silicone Pot Lid Gaskets are manufactured in an ISO 9001:2015 certified production facility, with strict quality control at every stage of the production process:
- Raw material inspection: Every batch of LSR raw material is tested for purity, hardness, and food contact compliance before entering the production line, with traceable batch numbers for all products.
- In-process inspection: 100% dimensional checking of every 50th unit during injection molding, with real-time monitoring of molding temperature, pressure, and curing time to ensure consistent product quality.
- Finished product testing: Each batch undergoes random testing for compression set, steam aging resistance, and food contact safety, with third-party testing reports available upon request.
- Warranty policy: We offer a 12-month warranty for all standard products against manufacturing defects, including deformation, cracking, discoloration, and seal failure under normal use conditions. Custom products come with a 6-month warranty tailored to your application requirements.
All products are packaged in food-grade plastic bags with clear size and hardness labeling, and we offer customized packaging options for OEM and distribution partners.