Gasket vs O-Ring: Which One to Choose?

Aug. 19, 2022

Both gaskets and O-rings serve a similar purpose-sealing liquids or gases in a specific application. However, these two types of seals differ greatly in appearance and are designed for different environments.

When choosing a seal for your application, how do you know if a gasket or O-ring is right for you? Here are the key differences between gaskets and O-rings that you need to consider.

O Ring

What is an O-Ring?

O-rings, also known as packing joints, are mechanical seals consisting of a round elastomeric material. They are designed to create a pressure-resistant sealing mating surface. In fact, some O-rings can withstand pressures in excess of 5,000 pounds per square inch (PSI). Even under extreme pressure, O-rings maintain their integrity while preventing liquids, gases or air from escaping the corresponding components used with them.

Although they are available in a variety of sizes, all O-rings are identical in shape. They consist of a ring-shaped elastomeric material with a hollow center. This round shape allows O-rings to be installed on cylindrical components such as pipes and hoses.

NR Black Rubber O Ring

Common applications requiring O-rings include

Hydraulic systems

Fuel systems

Medical and pharmaceutical

Oil

Pipe fittings

HVAC

What is a Gasket?

A gasket is a flat piece of material that sits between flat surfaces. The material of the gasket - whether it is neoprene, rubber, silicone or other flexible substance - prevents the penetration of liquid or air (or sometimes both) into or out of an area.

Gaskets can be cut into almost any shape. Many are round and circular, but others may be rectangular, square, triangular, semicircular - almost any form.

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As with the materials used, gaskets can be layered with many different coatings. These layers contribute to the end use and application. Gaskets can be laminated, pressure-sensitive adhesive layered, or a combination of several coatings.

NBR Round Flat Rubber Gasket

Common applications that require gaskets include

Electronics

Electric motors

Power generation

Transportation and automotive

Telecommunication equipment

What is the difference between O-ring and gasket?

Both the gasket and the o-ring have the same basic function of preventing liquid or gas from entering or exiting. The o-ring is a simple circular gasket composed of elastomeric material, and the gasket is a flat seal composed of any material or shape.

When deciding if an O ring or a gasket is better for your equipment designing, the shape of the seal is a critical factor for your choice. In some cases, only gaskets can work well because O-rings must require a groove to sit in.

Another key factor is the working environment, including temperature and pressure. Both O-rings and gaskets can work in a wide temperature range, but the gasket is a better choice in extreme temperatures. At the same time, O-rings are an excellent choice in extreme pressure. To a certain extent, O-rings perform better with increasing pressure, while the effectiveness of the gasket will decrease.

Contact Us for Your Gasket and O-Ring Needs

Sanshi Rubber is a quality manufacturer of custom O-rings and gaskets, offering a variety of materials and sizes to best meet our customers' needs. Our team has over 30 years of experience in sealing solutions. We are committed to the highest standards with a goal of 100% on-time delivery and 0% defect rate, and strive to provide the fastest turnaround times in the industry. To learn more about our cost-effective, durable sealing solutions, contact us today or request a quote.