FKM Rubber Gaskets  

FKM (Fluoroelastomer), also known as fluororubber, is a synthetic rubber with a high fluorine content, copolymerized from fluorinated monomers. The large number of C-F bonds in its molecular structure endow the material with excellent chemical resistance, high-temperature resistance, and anti-aging properties. Therefore, FKM rubber gaskets are widely used in industrial scenarios with strict sealing performance requirements. The following is a detailed introduction from aspects of core performance, typical application scenarios, advantages and limitations: 

 

 

## I. Core Performance of FKM Rubber Gaskets  

The molecular structure of FKM rubber is dominated by stable carbon-fluorine bonds, featuring strong chemical inertness and excellent physical and mechanical properties, specifically manifested as follows: 

 

### 1. Chemical Resistance 

- **Broad-spectrum medium resistance**: It has strong resistance to most organic solvents (such as ketones, esters, ethers, aromatic hydrocarbons), strong acids (such as sulfuric acid, nitric acid), strong alkalis, greases, hydraulic oils, fuel oils (including gasoline, diesel, aviation kerosene), and corrosive gases (such as chlorine, fluorine). It is not prone to swelling, hardening, or degradation.  

- **Adaptability to special environments**: It can maintain stable performance in strong oxidizing environments (such as scenarios containing ozone and hydrogen peroxide), making it one of the few rubber materials applicable to the sealing of strongly corrosive media. 

 

### 2. High-Temperature Resistance  

- **Long-term operating temperature range**: It can work stably for a long time in the range of **-20℃~200℃**. Some high-performance grades (such as perfluoroether rubber) can withstand short-term temperatures up to 260℃ or even 300℃, far exceeding the heat resistance limit of ordinary rubbers (such as EPDM and nitrile rubber). 

- **High-temperature stability**: It is not easy to soften, flow, or decompose in high-temperature environments, and has a low compression set rate (usually <30% under long-term high temperatures), which can continuously ensure the sealing effect. 

 

### 3. Anti-Aging and Weather Resistance  

- **Anti-aging ability**: It has strong resistance to oxygen, ozone, ultraviolet rays, and climatic aging (such as sunlight, rain, and humidity changes). It is not prone to cracking, hardening, or performance attenuation after long-term use, and its service life is much longer than that of ordinary rubber gaskets. 

- **Radiation resistance**: Some FKM grades have certain radiation resistance and can be used for sealing needs in low-dose radiation environments.  

 

### 4. Physical and Mechanical Properties 

- **Sealing performance and elasticity**: It has good elasticity and compression rebound, which can closely fit the sealing surface. Even under working conditions with vibration or pressure fluctuations, it can maintain reliable sealing and reduce the risk of leakage. 

- **Wear resistance and strength**: It has moderate surface hardness, better wear resistance than EPDM, and high tensile strength and tear strength, which can adapt to certain mechanical stresses. 

 

 

## II. Typical Application Scenarios of FKM Rubber Gaskets 

Based on the above excellent properties, FKM rubber gaskets are mainly used in industrial fields with extremely high requirements for sealing performance, temperature resistance, and corrosion resistance:  

 

### 1. Petrochemical and Fine Chemical Industry 

- Used for sealing reactors, storage tanks, pipeline flanges, and valves, adapting to various corrosive media (such as acid-base solutions, organic solvents, catalysts) and high-temperature working conditions (such as distillation and polymerization processes). 

- Adapt to the sealing of oil extraction equipment (such as drilling platform seals), refinery pipelines, and heat exchangers, resisting corrosion from crude oil, heavy oil, and various refined by-products. 

 

### 2. Automobile and Transportation 

- Automotive engine systems: Used for sealing high-temperature components such as fuel injection systems, gearboxes, and turbochargers, withstanding long-term erosion from engine oil, high-temperature coolants, and fuel.  

- New energy vehicles: Adapt to battery cooling systems and motor seals, resisting coolants (such as ethylene glycol solutions) and high-temperature environments, while meeting voltage resistance and insulation requirements. 

- Aerospace: Used for sealing aircraft engine fuel systems, hydraulic systems, and high-temperature pipelines, adapting to harsh environments such as high-altitude low temperatures, ground high temperatures, and aviation fuel. 

 

### 3. Machinery Manufacturing and Industrial Equipment 

- High-temperature machinery: Such as sealing gaskets for industrial furnaces, dryers, and steam pipelines, withstanding continuous high temperatures and thermal cycle impacts. 

- Hydraulic and pneumatic systems: Used for sealing high-pressure hydraulic equipment and pneumatic valves, resisting the long-term effects of hydraulic oil and compressed air, and not prone to aging and failure at high temperatures. 

 

### 4. Electronics and Semiconductor Industry  

- Semiconductor manufacturing equipment: Such as sealing components of etching machines and ion implanters, withstanding corrosive gases such as hydrogen fluoride (HF) and chlorine, and high-temperature process environments. 

- Electronic component sealing: Used for waterproof and dustproof sealing of high-temperature electronic equipment (such as power modules), adapting to the high-temperature environment during equipment operation. 

 

### 5. Food and Pharmaceutical Industry (Specific Grades) 

- Food-grade FKM gaskets that meet FDA (U.S. Food and Drug Administration) or USP (U.S. Pharmacopeia) standards can be used for sealing high-temperature sterilization equipment (such as steam sterilizers) and food processing machinery. They withstand corrosion from high-temperature steam and cleaning agents, are non-toxic, and do not release harmful substances. 

 

 

## III. Advantages and Limitations of FKM Rubber Gaskets  

### Advantages  

- **Extremely strong chemical resistance**: Adapt to most acids, alkalis, solvents, and corrosive media, with a much wider application range than ordinary rubber; 

- **Outstanding high-temperature resistance**: Can be used for a long time above 200℃, meeting the needs of high-temperature industrial scenarios; 

- **Anti-aging and long service life**: Excellent ozone and ultraviolet resistance, not easy to fail in outdoor or long-term use, reducing maintenance costs; 

- **High sealing reliability**: Good elasticity and compression rebound, can maintain effective sealing under vibration and pressure fluctuation conditions. 

 

### Limitations 

- **Limited low-temperature performance**: Ordinary FKM tends to harden and lose elasticity below -20℃, and low-temperature sealing performance decreases (special low-temperature grades need to be selected, which are more costly); 

- **High cost**: The price of raw materials is much higher than that of general-purpose rubbers such as EPDM and nitrile rubber, making it unsuitable for sealing needs in low-cost and non-harsh working conditions; 

- **Limitations on polar solvents**: Although it is resistant to most media, it may have a risk of swelling in a few strong polar solvents (such as low-molecular ketones), so compatibility testing in advance is required; 

- **Difficult processing**: The vulcanization molding process has high requirements, and temperature and time need to be precisely controlled, otherwise, performance may be affected. 

 

 

## IV. Selection Considerations 

- **Confirmation of medium compatibility**: According to the specific media in the use environment (such as acid, alkali, solvent type), verify compatibility through the chemical resistance data sheet provided by the manufacturer or actual tests; 

- **Temperature range matching**: Clarify the long-term use temperature and short-term peak temperature of the working condition, and select the FKM grade corresponding to the temperature resistance level (such as ordinary FKM or perfluoroether rubber);  

- **Consideration of low-temperature needs**: If the working condition involves a low-temperature environment (such as below -20℃), modified low-temperature FKM or perfluoroether rubber should be selected to avoid hardening and failure of the gasket; 

- **Balance between cost and performance**: In non-high-temperature and non-strongly corrosive scenarios, rubbers with higher cost performance (such as EPDM and nitrile rubber) can be preferred. FKM is more suitable for harsh working conditions. 

 

 

## Summary 

With the three core advantages of "chemical resistance, high-temperature resistance, and anti-aging", FKM rubber gaskets have become a "high-end solution" in the industrial sealing field to cope with harsh environments. They are particularly indispensable in high-demand scenarios such as petrochemicals, automobiles, and semiconductors. Although the cost is relatively high, their ultra-long service life and reliable sealing performance can significantly reduce the risk of equipment maintenance, making them an ideal choice for sealing high-value equipment.