The Longevity of Silicone O Rings

Silicone is an elastomer consisting of silicon, oxygen, hydrogen and carbon derived from quartz. It’s resistant to UV damage, ozone and lubricants. It also has good resistance to mineral and vegetable oils, diluted salt solutions and fire resistant hydraulic fluid.

Stockwell Elastomerics custom molds electrically conductive silicone o-rings in standard and custom geometries. They’re available in durometers from 10 through 70 Shore A.

Durability

The longevity of o-rings depends heavily on the quality of the material they are made from. There are a wide variety of o-ring materials available that can be used to meet the unique requirements of any application. For a durable seal in high-temperature environments, silicone rubber offers exceptional performance.

Silicone o-rings retain their flexibility and low compression set characteristics within one of the widest working temperature ranges of any elastomer, which makes them ideal for medical, semiconductor, automotive, aerospace, and electronics applications. Silicone o-rings are also resistant to hot air, ozone, and UV radiation. They are odorless, tasteless, and non-toxic. In addition, silicone can be compounded to be electrically conductive or flame retardant.

Some o-ring materials are prone to failure in high-temperature applications if not lubricated properly. This type of failure can occur from improper gland design, exposure to extreme temperatures, swelling, or contact with incompatible fluids. These types of failures are all preventable by using the right o-ring material for a given application. To learn more about o-ring durability and proper lubrication, visit this helpful O Ring Material Selection Guide from Martin’s Rubber.

Temperature Resistance

Silicone o rings resist temperature exposure well, operating between -84 and 232 degrees Celsius. There are also specific formulations of o-rings that can withstand even higher temperatures.

This is due to the high-energy silicon atoms and oxygen molecules in the chemical composition of silicone. These elements bond together with each other to make the material a better insulator against heat. Silicone o rings Similarly, o-rings made of FDA-approved silicones are suitable for use in food and medical applications as they don’t produce odor or taste.

VMQ o-rings can resist a variety of chemicals and liquids including mineral and vegetable oils, diluted salt solutions, engine oil and transmission fluid (FVMQ), high molecular weight chlorinated aromatic hydrocarbons and some acids. This material is also resistant to ozone and UV radiation, physiologically neutral and has good compression set resistance.

However, o-rings made of silicone have lower tear and abrasion strength than other materials, so they are recommended for static rather than dynamic applications. For dynamic applications, Engineered Seal Products recommends Viton o-rings. Viton o-rings work well in high-temperature applications and can seal against fuel, mineral or petroleum lubricants, engine and gear oils, halogenated hydrocarbons, and some chemicals.

Chemical Resistance

Silicone O rings are resistant to a wide range of chemicals, including weathering and ozone exposure. They are also able to hold their own against heat and cold exposure, making them an excellent choice for static sealing applications in harsh environments.

FDA-grade silicone seals are often utilized in food processing facilities, where the O ring’s material must be non-toxic and non-allergenic to prevent contamination of the food. This type of O-ring is also available in metal detectable versions, which are useful in identifying potential equipment malfunctions or leaks in production.

VMQ silicone O rings are an excellent choice for static, low-pressure chemical resistance applications and have good abrasion and tear strength, although they are not recommended for use in acids, petroleum oils or high molecular weight chlorinated aromatic hydrocarbons. These o-rings are also odorless and will not grow mold.

Nitrile o-rings are commonly used for low-cost, general-purpose industrial applications and can tolerate a broad range of temperatures, with standard tolerances between -65oF and +400oF. They offer excellent resilience and abrasion resistance, have low compression set and are highly tolerant of oil and ozone exposure.

Abrasion Resistance

As a highly flexible material, silicones are able to retain their flexibility and low compression set within one of the widest working temperature ranges of any elastomer. These properties make silicone an ideal choice for static seals where they are exposed to a variety of conditions such as dry heat, sunlight and ozone. In addition, this type of material has good flex and fatigue life and is physiologically neutral and odorless.

Specialty formulations of this material can also be made that are FDA-approved and food grade. This is often required in applications where the material will come into contact with food or beverage products.

Distributor and custom manufacturer of standard and specialty abrasion resistant O-rings. Value added services include assembly, barcoding, bin stocking, bonded inventory and consignment inventories, consolidated billing, JIT, Kanban, dock-to-stock and drop ship programs. Materials worked with include Buna-N, EPDM, neoprene, fluorosilicone, PTFE and Hypalon. Molding, cutting, turning, milling, drilling, slitting, sewing, bonding, etching and laser Silicone O Rings – Supplier or waterjet cutting capabilities offered. Serves aerospace, automotive, medical, chemical and electronics industries. ANSI, ASTM and DOT standards met.

Flame Retardant

Heat-resistant silicone o rings have excellent thermal stability, meaning that they can withstand extreme temperatures without becoming brittle. This is one of the main characteristics that makes them so popular for industrial applications. They are also odorless, non-toxic and will never grow mold. This type of O-ring is also a good choice for static applications because it can withstand the environmental factors that would otherwise damage or compromise the performance of other seals.

Silicone is an extremely versatile material that can be used to produce a variety of different types of seals. It can be molded into intricate, specialized shapes, and it has the ability to conform to tight tolerances. Moreover, it can be compounded to make it electrically resistant, conductive, or flame retardant.

Other materials, such as PTFE (polytetrafluoroethylene), can offer similar properties to silicone. However, they have higher cost compared to silicone. Besides this, they cannot work well in dynamic applications due to their low strength and poor abrasion resistance. They can be compromised by petroleum fluids, ketones, oxidative environments, alkalis, and superheated water or steam above 250 degrees Fahrenheit.