02.09.2022

Advantages of O-rings


O-rings are rubber sealing rings with a circular cross-section. Because their cross-section is O-shaped, they are called O-form sealing rings, also known as O-rings. It began to appear in the middle of the 19th century when it was used as the sealing element of the steam engine cylinder. O-rings are suitable for installation on various mechanical equipment, and they can seal under the specified temperature, pressure and different liquid and gas media in the static or moving state. Various types of sealing elements are widely used in machine tools, ships, automobiles, aerospace equipment, metallurgical machinery, chemical machinery, engineering machinery, construction machinery, mining machinery, petroleum machinery, plastic machinery, agricultural machinery and various instruments. O-rings still play a good sealing and damping role in oil, acid, alkali, abrasion, chemical erosion and other environments. Therefore, O-rings are the most widely used seals in the hydraulic and pneumatic transmission system. Compared with other types of sealing rings, O-rings have the following advantages:


1. Suitable for various sealing forms, including static sealing and dynamic sealing
2. Suitable for various materials, with standardized dimensions and grooves and strong interchangeability
3. Suitable for a variety of motion modes: rotary motion, axial reciprocating motion or combined motion (such as rotary reciprocating combined motion)


4. Suitable for many different sealing media: oil, water, gas, chemical media or other mixed media
5. By selecting suitable rubber materials and proper formula design, it can effectively seal oil, water, air, gas and various chemical media. The temperature range is wide (-60℃ - +220℃), and the pressure can reach 1500Kg/cm2 (used together with reinforcing ring) in fixed use


6. Simple design, compact structure and convenient assembly and disassembly


WHAT ABOUT FKM O-RINGS?


FKM o-rings and sealing gaskets are made of fluorocarbon elastomers and are extensive used over a wide span of industries. The characteristics of FKM o-rings and seals made them highly desirable in many applications. FKM, also known as Fluorocarbon is a brand of synthetic rubber and fluoropolymer elastomer. Standard durometers are 75 and 90 and they typically come in black or brown. The temperature range is generally -15-degrees to 400-degrees. FKM is available in standard and metric sizes. FKM has good resistance to petroleum products and a wide spectrum of chemical compatibilities. Recommended uses include vacuums, most acids and chemicals, halogenated hydrocarbons, di-ester lubricants, petroleum oils and fuels, silicone oils and greases. FKM has excellent resistance to high temperatures, ozone, oxygen, mineral oil, synthetic hydraulic fluids, fuels, aromatics and many organic solvents and chemicals. FKM is not recommended for hot water and steam, and also has problems with ketones, auto and aircraft brake fluids, amine (ammonia), acetone, skydrol, ethyl acetate, and low molecular esters and ethers. FKM is not recommended for low temperature uses and for static applications is limited to approximately -15-degrees although in certain situations it is suitable down to -40-degrees. Under dynamic conditions the lowest service temperature is between 5 to 0-degrees. FKM has good wear resistance, excellent compression set resistance, moderate short-term resilience and excellent permeation resistance. It is good for vacuum service and low gas permeability.


What is fluorosilicone O-ring?


Fluorosilicone, also known as GAMMA-trifluoropropyl methyl polysiloxane. Also 0.3% or 0.5% vinyl siloxane copolymer modified material is introduced into the molecular structure chain. The crystal is a completely transparent and highly viscous plastic deformed linear polymer compound. The main chain is composed of silicon and oxygen atoms. The side groups connected to the silicon are methyl, vinyl and trifluoropropyl, and the content is 60-900000 In the range. With various preservatives, the rubber is mixed into homogeneous plastic particles. Under the action of organic chemical peroxides, rubber can be vulcanized into various tough rubber products.Fluorosilicon O-ring not only has the characteristics of ordinary silica gel, but also has the characteristics of high-quality aviation light oil, gear oil, automobile oil, chemicals and organic solvents. It can work for a long time at 56～150℃. Due to its excellent performance, fluorosilicone gel O-ring is used in aviation, automobile and other industries. The performance advantages of fluorosilicone O-ring seals combine :




Use temperature range -60 to 260 degrees.




Retain the advantages of high tensile retention of silicone rubber at high temperatures.





Good insulation performance.




Low air permeability, in line with environmental requirements. Therefore, it is used for high-low temperature, oil-resistant and medium-resistant fluorosilicone O-rings.




SILICONE O-RING ADVANTAGES


Silicone O-rings are one of the most common sealing components used today. Silicone is an industry standard for a wide range of applications, and it is prized for its simplicity, ease of use, and cost-effectiveness. Silicone rubber O-rings have numerous desirable features that make them popular for a wide range of products. With numerous beneficial characteristics, silicone rubber O-rings are the ideal sealing components for a wide variety of applications across many diverse industries. They perform well in environments where other materials may suffer, such as in dry heat. The superior electrical insulating properties of high-temperature O-rings make them highly desirable for applications subject to strict performance standards. Silicone rubber O-rings are also used in FDA-approved food handling equipment and appliances. Silicone rubber makes the ideal material for O-rings, as it is flexible, stable, non-reactive, and capable of withstanding high temperatures and extreme environmental conditions. Heat-resistant silicone O-rings are resistant to a temperature range of up to 310° C or 590° F and as low as -100° C or -148° F. In limited circumstances, they may also exceed those tolerances for short durations. Silicone O-rings also exhibit a low compression set, meaning they are ideal for compression force sealing and applications where high pressures or temperatures exist. These highly resilient components are also resistant to chemicals, acids, alkali, and ozone. In industries where aesthetics is a factor, silicone O-rings can be matched to any RAL or Pantone number for a highly customized look. While the list of advantages of high-temperature O-rings is extensive, they are subject to some limitations. Silicone does not have the tensile strength of some alternative materials, nor does it have high resistance to tears and abrasions. This means that silicone O-rings are not well-suited for dynamic applications. Silicone is also more permeable than other materials, so it is not suitable for direct exposure to steam, fuel, or gear lubricants.


The Applications And Advantages Of PTFE


PTFE or Polytetrafluoroethylene is a versatile and high-performance fluoropolymer made up of fluorine and carbon atoms and is highly used as a non-stick coating in kitchen cookware. PTFE is a hydrophobic and most chemically inert polymer, making it unaffected by a lot of gases, vapours, and fluids. It offers excellent mechanical properties like thermal insulation and corrosion resistance. PTFE is suited well for temperatures between -400°F to 500°F. The unique properties of PTFE allow for versatility to be used in a huge number of applications across different industries ranging from basic home cookware to high-grade medical tools. Because of its exceptional qualities, PTFE can withstand even in the harshest of conditions, making it appropriate for a wide range of applications. From cooking equipment to food coverings, conveyor belt rollers, temperature sensor, and non-stick surface covers, this fluoroplastic is perfect for use in the food and beverage industry. PTFE may be used to create a variety of items in the chemical sector, including gaskets, vessel linings, and chemical tanks. PTFE is also commonly used in high-temperature applications, such as terminal insulation on heating components in jet engines, UV lights, and exterior aircraft fittings. Medical applications including the fabrication of internal and exterior life-saving equipment such as catheters, bio-containment vessels, syringes, and sutures benefit from the usage of PTFE material. This one-of-a-kind fluoropolymer is also ideal for electrical insulation and electronic component protection. Also, PTFE offers many unique advantages. These include:




Wide operating temperatures (-400° F to 500° F)




Resistance to Corrosion (great replacement for rubbers which are affected by corrosion)




Excellent Electrical Properties




Unlimited Shelf Life




High resistance to water, moisture & UV




Low coefficient of friction




High Flexural Strength

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