Overview
Silicone O-rings are versatile elastomeric sealing components widely recognized for their exceptional temperature resistance, excellent flexibility, and biocompatibility. Manufactured from high-quality silicone rubber (VMQ - vinyl methyl silicone), these O-rings provide reliable sealing performance across a broad range of temperatures and are available in food-grade, medical-grade, and industrial formulations. OrroMFG produces precision silicone O-rings that meet the most stringent international standards, including FDA, USP Class VI, ISO 10993, and 3-A sanitary requirements.
Silicone O-rings offer superior performance in applications where extreme temperature variations are encountered, maintaining excellent elasticity and sealing force from arctic cold to high-temperature environments. Their inherent biocompatibility makes them the preferred choice for food processing, pharmaceutical manufacturing, and medical device applications. We offer an extensive range of standard AS568 sizes as well as custom dimensions to meet specific application requirements. All our silicone O-rings undergo rigorous post-curing to ensure low volatile organic compound (VOC) content and optimal mechanical properties.
Key Features
- Wide Temperature Range: Continuous service from -60°C to +230°C (-76°F to +446°F), with special grades rated to +300°C.
- Excellent Biocompatibility: Food-grade and medical-grade formulations meet FDA 21 CFR 177.2600, USP Class VI, and ISO 10993 requirements.
- Superior Low-Temperature Flexibility: Remains flexible and resilient at temperatures well below the glass transition of most other elastomers.
- Good Weathering and Ozone Resistance: Excellent resistance to UV radiation, ozone, and weathering for outdoor applications.
- Low Compression Set: Maintains sealing force over extended service life with minimal permanent deformation.
- Plasma Sterilization Compatible: Suitable for autoclaving, gamma irradiation, and ethylene oxide (EtO) sterilization methods.
Material Specifications
| Property | Standard Silicone | Food-Grade Silicone | Medical-Grade Silicone | High-Temp Silicone |
|---|---|---|---|---|
| Hardness (Shore A) | 50 - 80 | 50 - 70 | 50 - 70 | 60 - 80 |
| Tensile Strength (MPa) | 7 - 10 | 8 - 11 | 9 - 12 | 8 - 10 |
| Elongation at Break (%) | 200 - 500 | 300 - 600 | 400 - 700 | 150 - 300 |
| Tear Strength (kN/m) | 15 - 30 | 20 - 35 | 25 - 40 | 15 - 25 |
| Compression Set (%) | ≤ 20 | ≤ 15 | ≤ 10 | ≤ 25 |
| Service Temp Range (°C) | -60 to +230 | -60 to +220 | -60 to +220 | -50 to +300 |
| Density (g/cm³) | 1.10 - 1.25 | 1.12 - 1.20 | 1.10 - 1.18 | 1.15 - 1.30 |
| Volume Swell in Water (%) | ≤ 2 | ≤ 1.5 | ≤ 1 | ≤ 2 |
| FDA 21 CFR 177.2600 | - | Yes | Yes | - |
| USP Class VI | - | - | Yes | - |
Applications
Food and Beverage Processing
Food-grade silicone O-rings are extensively used throughout the food and beverage industry for sealing applications involving direct food contact. They are found in processing equipment such as pumps, valves, pipe connections, heat exchangers, filling machines, and conveyor systems. Typical applications include dairy processing, beverage bottling, bakery equipment, meat and poultry processing, and brewing systems. They are particularly valued for their ability to withstand frequent cleaning cycles with hot water and caustic cleaning agents (CIP/SIP systems).
Pharmaceutical and Biotechnology
Medical-grade silicone O-rings meeting USP Class VI and ISO 10993 standards are essential in pharmaceutical manufacturing and biotech processes. They are used in sterile manufacturing equipment, bioreactors, filtration systems, drug delivery systems, and laboratory equipment. Their compatibility with sterilization methods including autoclaving, gamma irradiation, and ethylene oxide treatment makes them indispensable in aseptic processing environments.
Medical Devices
Silicone O-rings are widely incorporated into medical devices and healthcare equipment due to their biocompatibility and reliable performance. Applications include syringe pumps, respiratory equipment, dental instruments, surgical tools, implantable devices (when properly certified), and diagnostic equipment. Their soft, flexible nature minimizes tissue irritation and ensures patient safety.
HVAC and Appliances
In heating, ventilation, and air conditioning systems, silicone O-rings provide reliable sealing for water heaters, boilers, heat pumps, and refrigeration systems. They are also used in household appliances such as coffee makers, food processors, steam ovens, and washing machines where temperature resistance and food safety are important.
Automotive and Aerospace
Silicone O-rings are used in automotive and aerospace applications where extreme temperature variations are encountered, including engine seals, cooling system connections, lighting assemblies, and sensor seals. Their excellent resistance to temperature extremes and weathering ensures long-term reliability in demanding environments.
Operating Conditions
- Temperature Range: -60°C to +230°C (-76°F to +446°F) standard; specialty grades from -80°C to +300°C
- Pressure Range: Up to 100 bar (1450 psi) for static sealing; up to 50 bar (725 psi) for dynamic sealing applications
- Media Compatibility: Water, steam, air, ozone, UV light, food products, pharmaceutical products, mild acids and bases, animal and vegetable oils
- Not Recommended For: Petroleum oils, gasoline, diesel, aromatic hydrocarbons, halogenated solvents, concentrated acids
- Sterilization Compatibility: Autoclaving (121°C/134°C), gamma irradiation, ethylene oxide (EtO), dry heat
- Weathering Resistance: Excellent resistance to ozone, UV radiation, and outdoor weathering
Material Comparison
| Material | Temp Range | Food/Medical Grade | Chemical Resistance | Compression Set | Cost | Best For |
|---|---|---|---|---|---|---|
| Silicone (VMQ) | -60 to +230°C | Yes (special grades) | Fair-Good | Good | Medium | Food/pharma, high/low temp, medical devices |
| EPDM | -50 to +150°C | Yes (FDA grades) | Good-Good | Good | Low | Water service, HVAC, outdoor exposure |
| NBR (Nitrile) | -30 to +120°C | Limited | Good | Fair | Low | Petroleum oils, general industrial use |
| Viton (FKM) | -20 to +200°C | Limited | Excellent | Very Good | High | Aggressive chemicals, high-temperature oil |
| PTFE | -200 to +260°C | Yes | Excellent | Excellent | High | Extreme chemicals, cryogenic, high temp |
Choose silicone O-rings when:
- Food-grade or medical-grade sealing is required
- Wide temperature range operation is needed
- Low-temperature flexibility is critical
- Biocompatibility and sterilization compatibility are required
- UV and ozone resistance are important for outdoor use
Customization Options
- Material Grades: Standard industrial silicone, FDA food-grade, USP Class VI medical-grade, high-temperature silicone, low-temperature silicone, flame-retardant silicone, conductive silicone
- Hardness Range: 40 Shore A to 90 Shore A, with 50, 60, 70 Shore A as most common
- Size Range: 0.5mm to 2000mm inner diameter; standard AS568, BS, ISO, JIS sizes available
- Cross-Sections: 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 5.0mm, 5.7mm, 7.0mm, and custom sizes
- Color Options: Transparent/clear, white, red, black, blue, green, and custom colors for food/medical identification
- Special Profiles: X-rings, square rings, D-rings, custom profiles, and back-up ring assemblies
- Post-Curing Options: Standard post-cure, extended post-cure for low VOC, platinum-cured for medical applications
- Surface Treatments: PTFE coating, silicone oil coating, and dry film lubricants for assembly assistance
Quality Assurance
At OrroMFG, quality is at the forefront of silicone O-ring manufacturing. Our production facilities operate under ISO 9001:2015 certification, with cleanroom production capabilities for medical-grade products. We source only premium silicone raw materials from leading global suppliers, with full material traceability from batch to finished product.
Every production lot undergoes comprehensive quality testing including dimensional verification, hardness testing, tensile strength testing, elongation measurement, tear strength evaluation, and compression set testing. Food-grade and medical-grade products are tested for extractables and leachables compliance, with supporting documentation including FDA declarations of compliance, USP Class VI test reports, and biocompatibility certificates. We maintain strict process control throughout molding, post-curing, and finishing operations to ensure consistent product quality. Our in-house quality control team performs incoming material inspection, in-process monitoring, and final release testing. All products are supplied with material certificates, inspection reports, and full traceability documentation, giving our customers complete confidence in the reliability and safety of our silicone O-rings.
