Advantages and Disadvantages of Silicone O Rings
There are many different o-ring materials available that can be used to make mechanical seals. Each type of o-ring has its own advantages and disadvantages depending on the application and operating conditions.
Silicone (VMQ) o rings offer excellent hot air, ozone, and UV resistance along with good abrasion and tear performance. They also have high chemical resistance to engine and transmission oil, animal and vegetable oils and greases.
Bio-Inert
Silicone o-rings are a staple in many industrial applications. They don’t react with many chemicals, a feature that makes them useful in the food and medical industries. For example, o-rings used in critical care equipment like ventilators must maintain an airtight seal during sterilization processes to ensure patient safety. Because of their non-reactivity, silicone o rings can withstand the harsh conditions of these machines while keeping an effective seal.
In addition, they are less permeable to Silicone o rings gasses than other elastomers and offer excellent resistance to extreme temperatures. They can operate in a wide temperature range from -60 to 225 degrees Celsius with some special compounds able to withstand even higher temperatures.
Furthermore, they can be compounded with a variety of properties to make them electrically resistant, conductive or flame retardant. This means that they can be used in a broad range of electronics applications, including in mobile devices and automobiles. They are also known for their ability to resist petroleum-based fluids and oil, which is a significant benefit for many automotive and industrial users of o-rings.
Temperature Stability
The ability to withstand a wide range of temperatures makes silicone o rings ideal for a broad spectrum of applications. This is particularly true in the electronics industry, where high temperatures are a frequent occurrence. Silicone o rings can withstand extreme temperatures without sacrificing their durability or flexibility.
This capability to withstand temperature changes sets silicone apart from other o-ring materials such as Viton or neoprene, which are more sensitive to heat and degrade more quickly. It also allows silicone o-rings to maintain their structural integrity even in abrasive or dynamic environments.
Another advantage of silicone o-rings is that it doesn’t degrade under tensional or compressional forces. This quality, known as tensile strength, is measured by using a tensometer to determine the amount of force required to break or deform an object.
These characteristics, along with the non-reactivity of silicone to biological materials, make it a popular choice for medical, food, and pharmaceutical applications. In addition, it is also resistant to ozone, UV rays, and weathering conditions. Other common high-temperature o-ring materials include FFKM or perfluoro elastomers, and PTFE or Teflon.
Flexibility
Known for their flexibility and resilience, silicone o rings are capable of resisting a wide range of temperature conditions. They can be used in a variety of applications including machinery that operates under extreme temperatures as they are not susceptible to hot air or ozone, unlike other types of o-rings such as Nitrile (NBR) blends or Viton.
Silicone O Rings have a high resistance to chemicals and oil, making them a reliable sealant for a broad spectrum of industries. They also possess the highest tolerance to weather conditions of any o-ring material. They can withstand temperature variations up to 310 degrees Celsius and down to -100 degrees Celsius, although they are not recommended for use in dynamic applications because of their poor abrasion and tear resistance.
In addition to their thermal stability, silicone o-rings offer excellent electrical insulation. They can effectively seal gaps and prevent the transfer of electricity, making them a preferred choice for electronics and other electrical equipment. They can also be molded using various fillers to improve tensile strength, resistance to ozone or UV radiation, and other physical properties.
Durability
Silicone o rings can hold up against a range of environmental conditions. They’re also easy to clean and disinfect, reducing the risk of bacteria growth or cross-contamination. In the medical and pharmaceutical industry, silicone o rings are FDA-approved for metal detectable use, making them ideal for drug-delivery systems like insulin pumps.
The chemical makeup of silicone is what makes it more resistant to heat than other o-ring materials. It has an inorganic backbone of silicon atoms with alternating oxygen atoms that creates high-energy bonds. It’s also odorless, mold-resistant and won’t grow mildew, so it can be used in wet environments.
While silicone is a suitable material for static applications, it’s not a good choice for dynamic seals due to its low tensile strength. O-ring tensile strength is determined by using a tensometer, which measures the tensional force it takes to deform the material or break it. Other O-ring materials, such as EPDM and nitrile, have better tensile strengths but don’t offer the same resistance to chemicals, weather or temperature extremes as silicone.
Wide Range of Applications
Silicone O Rings are used in a wide range of applications. Their ability to withstand high temperatures and pressures, as well as their resistance to chemicals, acids, alkali, ozone and UV radiation make them a very popular choice in many applications. Encapsulated O Rings are made up of an elastomer stimulating core (Fluorocarbon Viton/FPM/Silicone) with a seamless FEP or PFA shield, which are chemically resistant to prevent corrosive fluids or gases from reaching the elastomer and causing damage or failure.
The o-ring is a simple but invaluable mechanical gasket Silicone o rings with many uses in industrial equipment. While there are numerous considerations when selecting o-ring material for an application, the most important factors include operating conditions, chemical compatibility, sealing pressure, durometer, temperature, abrasion and tear resistance, ozone influence and electrical resistance properties.
In food processing environments, silicone O rings are ideal as they can withstand a wide range of temperatures while maintaining an effective seal. This can be particularly beneficial when utilizing machines that involve heating and cooling, such as beverage dispensers. Additionally, they are FDA metal detectable, a requirement for many food-related applications.