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FKM 0-Rings
O-rings: Fluororubber (FPM, FKM) material
KODA offers a full range of fluororubber O-rings, covering all AS568 standard and metric sizes. Click the button below to view the complete fluororubber O-ring catalog; if you require a special type or size not currently in stock, please submit an inquiry for customization.
Fluororubber (FKM) O-rings are an ideal solution for industrial sealing, especially suitable for applications involving contact with corrosive chemicals, fuels, oils, or high-temperature conditions. These seals exhibit excellent resistance to a variety of chemicals, including acids, solvents, and hydrocarbons, and can withstand a wide temperature range, typically -15℃ to +200℃ (-5℉ to +392℉), with specific limits depending on the formulation of the FKM compound used.
What is fluororubber (FKM)?
Fluororubber (FKM) is a class of highly fluorinated hydrocarbon copolymers, first developed in the 1950s. FKM seals exhibit excellent resistance to various media, ozone, and aging, maintaining stable performance over long periods in fuels, petroleum-based oils, greases, and aliphatic and aromatic hydrocarbon media.
This material has limitations in its resistance to certain media and is unsuitable for polar solvents (such as acetone, methyl ethyl ketone, and ethyl acetate), low molecular weight organic acids (such as formic acid and acetic acid), ethylene glycol-based brake fluids, ammonia, amines, alkaline solutions, and superheated steam environments. FKM can be prepared using copolymers, terpolymers, and quaternary copolymers with fluorine content ranging from 65% to 71%, allowing for precise customization of material formulations based on specific requirements for media resistance and low-temperature flexibility.
This unique advantage enables FKM seals to be reliably used in the chemical and pharmaceutical industries, in harsh environments where they come into contact with corrosive media and where process temperatures exceed 140°C—conditions that conventional sealing materials such as EPDM and HNBR cannot meet.
Fluororubber (FKM), as a peroxide cross-linked material, possesses extremely high purity, excellent resistance to various media, and superior temperature resistance. These properties make it widely applicable as a static or dynamic seal in various scenarios. Currently, this material is widely used in the manufacture of O-rings, diaphragms, and other sealing elements.
The typical operating temperature range for fluororubber is -25℃ to 200℃, with core applications covering sealing components in the automotive and commercial vehicle manufacturing, oil extraction, chemical, and aerospace industries. Some specially formulated fluororubbers maintain good flexibility even in environments as low as -40℃. In general industrial applications, fluororubber seals are often used in high-speed, high-temperature conditions, with typical applications including radial shaft seals in pump bodies and transmissions.
Core Characteristics and Technological Advantages of Fluororubber (FKM) O-rings
Chemical Resistance: FKM O-rings exhibit excellent chemical corrosion resistance, allowing for stable application in harsh conditions involving various corrosive media.
Temperature Resistance: These seals demonstrate outstanding high-temperature resistance, making them suitable for applications in automotive engines, aerospace components, industrial machinery, and other high-temperature environments.
Compression Set Resistance: FKM O-rings possess excellent resistance to compression set, maintaining their original shape and sealing performance even after prolonged compression, ensuring reliable sealing.
Low Gas Permeability: The fluorocarbon elastomer substrate imparts low gas permeability, resulting in superior performance in sealing applications with stringent requirements for gas-liquid leakage protection.
Multiple Hardness Options: FKM O-rings are available in various hardness grades to precisely match the personalized sealing needs of different applications.
Long Service Life: With proper selection and installation, FKM O-rings can achieve an exceptionally long service life, effectively reducing equipment maintenance and seal replacement costs.
| Compounds | Durometer | Color | Temp Range (F) | Description |
|---|---|---|---|---|
| V70-B101 | 70 | Black | -40 to +482 | UL 157 |
| V70-B103 | 70 | Black | -15 to +400 | High chemical resistance |
| V70-B602 | 70 | Red | -13 to +482 | Automotive, General Purpose |
| V70-B501 | 70 | White | -4 to +482 | USP Class VI Certified |
| V75-B101 | 75 | Black | -13 to +482 | Genuine Viton, UL157 |
| V75-B102 | 75 | Black | -13 to +482 | General Purpose Genuine Viton |
| V75-B108 | 75 | Black | -4 to +482 | Genuine Viton, Type B |
| V75-B106 | 75 | Black | -13 to +482 | FDA Compliant |
| V75-B105 | 75 | Black | -13 to +482 | Chemours Genuine Viton - JDM H4P |
| V75-B201 | 75 | Brown | -13 to +482 | General purpose Genuine Viton |
| V75-B601 | 75 | Red | -13 to +482 | FKM, General Purpose |
| V75-B104 | 75 | Black | +5 to +428 | Viton ETP, Excellent chemical resistance |
| V75-F401 | 75 | Blue | -15 to +450 | Metal Detectable |
| V90-B101 | 90 | Black | -13 to +482 | General purpose Genuine Viton |
| V90-B107 | 90 | Black | -49 to +392 | FKM, RGD, Extreme Low Temp |
| V90-B201 | 90 | Brown | -13 to +482 | General purpose |
| V90-B102 | 90 | Black | -13 to +482 | Rapid Gas Decompression, General Purpose |
| V90-B104 | 90 | Black | -40 to +482 | Rapid Gas Decompression, Low Temp |
| V90-B103 | 90 | Black | -13 to +482 | Chemours Genuine Viton - JDM H4R |
| V90-B701 | 90 | Green | -13 to +482 | High-Visibility Genuine Viton |
| V1238-95 | 95 | Black | -15 to +400 | Rapid gas decompression resistance |
| V95-B101 | 95 | Black | -4 to +482 | Rapid gas decompression resistance, Genuine Viton |
Explanation of the differences in fluid resistance properties of different types of fluororubber
| Fluid | A | B | F | GLT | GFLT | ETP |
|---|---|---|---|---|---|---|
| Hydrocarbon Automotive, Aviation Fluid | Excellent | Excellent | Excellent | Excellent | Excellent | Excellent |
| Aliphatic Hydrocarbon Process Fluids | Excellent | Excellent | Excellent | Very Good | Excellent | Excellent |
| Aqueous Fluids: Water, Steam, Mineral Acids | Good | Very Good | Very Good | Excellent | Excellent | Excellent |
| Oxygenated Automotive Fuels | Not Recommended | Very Good | Excellent | Not Recommended | Excellent | Excellent |
| Reciprocating Engine Lubricating Oils (SG-SH Grade) | Not Recommended | Very Good | Very Good | Excellent | Excellent | Excellent |
| Amines, High pH Caustics | Not Recommended | Not Recommended | Not Recommended | Good | Good | Excellent |
| Low Molecular Weight Carbonyls | Not Recommended | Not Recommended | Not Recommended | Not Recommended | Not Recommended | Excellent |
| Reciprocating Engine Lubricating Oils (SE-SF Grade) | Very Good | Excellent | Excellent | Excellent | Excellent | Excellent |
| Aromatic Hydrocarbon Process Fluids | Very Good | Very Good | Excellent | Very Good | Excellent | Excellent |