An O-ring is a loop of elastomer/rubber with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal.
The O-ring may be used in static or dynamic applications where relative motion exists between the parts and the O-ring. Dynamic examples include rotating pump shafts and hydraulic cylinder pistons.
O-rings are one of the most common seals used in machine design because they are inexpensive, easy to make, reliable, and have simple mounting requirements. They can seal tens of megapascals (thousands of psi) of pressure.
Common Uses:
O-rings are found in a wide range of industries, including:
- Waterworks
- Military & Defence
- Medical &life sciences
- Semiconductor
- Agriculture
- Food processing
- Oil & Gas
- Chemicals
- Automotive
O-Ring
What Is an O-Ring Good For?
The versatility of the O-ring is evident in its broad range of applications. Here are some of its key uses:
- Leak Prevention: O-rings are designed to seal gaps between two mating surfaces, effectively preventing fluids and gases from escaping in systems like hydraulic cylinders, pumps, and valves.
- Dynamic and Static Sealing: Whether the sealing surfaces are stationary or in relative motion, O-rings provide reliable performance, making them suitable for applications involving vibration or movement.
- Cost-Effective and Durable: With a simple design and low production cost, O-rings offer an economical sealing solution while maintaining durability and performance under various operating conditions.
Rubber O Rings
Choosing the Right O-Ring: Size and Material Considerations
Selecting the appropriate O-ring involves careful consideration of both its physical dimensions and the properties of the material:
- Size and Fit
- Standard Sizing: O-rings are available in standardized sizes (such as those defined by ISO 3601 or SAE standards), which simplifies selection for many applications.
- For AS-568 Dimensions: https://www.technoad.com/engineering/dimensions/as-568-parker/
- For ISO 3601Dimensions: https://www.technoad.com/engineering/dimensions/iso-3601/
- Measurements: The two critical dimensions are the inner diameter (ID) and the cross-sectional diameter (CS). These must match the groove dimensions in the application to ensure proper compression and sealing.
- Tolerance and Compression: Proper sizing also involves understanding the amount of compression (or squeeze) required for an effective seal. Too little compression might result in leaks, while too much can lead to premature wear or damage to the O-ring.
https://www.technoad.com/engineering/gland-designhttps://www.technoad.com/engineering/dimensions/
- Material Selection
- Chemical Compatibility: The choice of material should be compatible with the fluids or gases in the system. https://www.technoad.com/engineering/material-selection-guide
- Temperature Range: Different materials have varying temperature limits. Ensure that the selected O-ring can handle both the minimum and maximum operating temperatures of your application.
- Pressure Ratings: Consider the operating pressure of your system. Some materials are more resistant to high-pressure environments and are less likely to extrude (i.e., get forced out of the groove under pressure).
- Wear and Life Expectancy: For applications with dynamic movement, choose materials known for their wear resistance and longevity.
O Ring Seal
Types of elastomers
- NR – Natural rubber
- NBR – Acrylonitrile butadiene, Nitrile or Buna N
- HNBR – Hydrogenated nitrile, or highly saturated nitrile
- XNBR – Carboxylated nitrile
- NBR/PVC – Nitrile/PVC resin blends
- EPM, EPDM – Ethylene Propylene, and Ethylene Propylene Diene rubber
- CR – Neoprene, Polychloroprene
- IIR – Butyl
- SBR – Styrene-Butadiene
- VMQ – Silicone
- FVMQ – Fluorosilicone
- AU, EU – Polyurethane
- FKM – Fluorocarbon elastomer (Viton™)
- FFKM – Perfluorocarbons elastomer (Kalrez®)
- PTFE – Polytetrafluoroethylene (Teflon™)
- FEP – Fluoroethylenepropylene, is the melt-processable version of PTFE
- PFA– Perfluoralkoxy, is a high temperature version of FEP
- TFE/P – Tetrafluoroethylene Propylene (Aflas®) (FEPM)
Techno Ad – Explore the Possibilities
Techno Ad offers O-rings in a wide array of sizes (AS568, ISO 3601, BS 4518, GB, JIS, SMS 1586, millimetric and non-standard sizes) and in various properties (hardness, compression-set, etc.),materials, and standard and certified compounds for drinking water, medical device, military / defense, etc. Additionally, we can supply O-rings that adhere to the highest military specifications, FDA, NSF61, and other standards.
Our extensive stock of O-rings includes over 10,000 different sizes and 30 million total pieces, including Viton™ and Kalrez®.
Small minimum order quantities (MOQ) can be processed for in-stock O-rings.
New tooling can be manufactured to produce a special size per customer’s drawing – ask us for a quotation.
Frequently Asked Questions About O-Rings
What is an O-Ring and what is it used for?
An O-Ring is a circular-shaped sealing element designed to prevent the leakage of fluids or gases between two components. At Techno Ad, we supply O-Rings manufactured to the highest standards, carefully matching the right material and dimensions to each client’s specific application — from industria grade to waterworks, defense, and medical sectors.
What materials are O-Rings made from?
At Techno Ad, we work with a wide range of materials to suit diverse application requirements: NBR (Nitrile), EPDM, FKM (Viton ™ ), Silicone, PTFE, AFLAS®, FFKM (Kalrez®) and more. Each material is selected based on its resistance to temperature, chemicals, pressure, and compliance with relevant industry standards.
How do I choose the right type of O-Ring?
The correct O-Ring is selected based on operating conditions: temperature range, pressure levels, type of fluid or gas involved, dynamic or static use, and more. Our team at Techno Ad specializes in providing in-depth professional consultation and, when necessary, customized sealing solutions — including tailor-made developments according to specific technical requirements or standards.
Can you provide custom O-Rings?
Absolutely. Techno Ad offers custom O-Ring manufacturing to meet unique design specifications, special material requirements, or non-standard sizes. Our technical team works closely with each client to ensure that every customized O-Ring perfectly matches the application’s demands, ensuring optimal sealing performance and longevity.
What certifications and quality standards do your O-Rings meet?
Quality is a top priority for us at Techno Ad. Our O-Rings can comply with various international standards, such as ISO, ASTM, FDA, USP Class VI, and more, depending on the application. We also offer full traceability and documentation when required.
How should O-Rings be stored to ensure maximum shelf life?
To preserve the quality and elasticity of O-Rings, we recommend storing them in a cool, dry place away from direct sunlight, ozone sources, and extreme temperatures. At Techno Ad, we also provide storage guidance and packaging solutions that help maintain the O-Rings in optimal condition until they are installed.
Can you assist with failure analysis of O-Rings?
Yes, we can. If a sealing issue occurs, our technical team at Techno Ad is available to conduct a comprehensive failure analysis to identify the root cause. We provide actionable recommendations for material upgrades, design modifications, or installation improvements to ensure better performance going forward.
What industries do you serve with your O-Rings?
Techno Ad serves a wide variety of industries, including waterworks, irrigation, medical devices, food processing, energy, defense, and general manufacturing. Our ability to offer both standard and highly customized O-Ring solutions makes us a preferred partner for critical applications across sectors.
Do you offer assistance with prototype and R&D projects involving O-Rings?
Definitely. We actively support R&D departments and prototype development by offering material expertise, rapid production of sample O-Rings, and consultation throughout the design validation stages. TechnoAd is committed to helping clients bring innovative products to market faster and with greater reliability.