PTFE Seals PTFE Lip Seals PTFE Oil Seals

Polytetrafluoroethylene seal (PTFE) (also known as PTFE seal ring or PTFE oil seal) is a high-performance sealing material with many unique advantages, such as excellent chemical resistance, excellent high temperature resistance, and low friction coefficients etc.

Advantages of PTFE seals

1. Good chemical corrosion resistance:

PTFE seals have excellent chemical corrosion resistance and can resist erosion by various chemical substances such as acids, alkalis, and salts. This characteristic makes PTFE seals widely used in chemical industry, pharmaceutical industry and food industry.

2. Excellent high temperature resistance:

PTFE seals have high high temperature resistance and can work in extreme high temperature environments for long periods of time. The melting point of PTFE is 327°C, the continuous use temperature range is -200°C to 260°C, and the short-term use temperature can reach 300°C, so it can work stably in high temperature environments. This characteristic makes PTFE seals widely used in aviation, aerospace, nuclear power and other fields.

3. Low friction coefficient:

Polytetrafluoroethylene seals (also known as PTFE seals or PTFE oil seals) have extremely low friction coefficients, making them highly efficient and long-life in sealing moving parts. This characteristic makes PTFE seals widely used in machinery, automobiles, ships and other fields.

4. Good electrical insulation properties:

PTFE seal is an excellent electrical insulation material that can work stably in high voltage environments. This characteristic makes PTFE seals widely used in electronics, electrical and other fields.

5. Good wear resistance:

PTFE seals have good wear resistance and can serve for a long time under harsh conditions such as heavy load, high speed, and high temperature. This characteristic makes PTFE seals widely used in heavy industries such as engineering machinery and petrochemical industry.

2. Disadvantages of PTFE seals——

1. Higher price:

Compared with other sealing materials, the price of PTFE seals is higher, which is also one of the factors limiting its popularity.

2. Low intensity:

PTFE seals have relatively low strength and are susceptible to mechanical shear forces, so they may not be suitable in some high-load, high-pressure applications.

3. Large expansion coefficient:

Polytetrafluoroethylene seals (also known as PTFE seals or PTFE oil seals) have a relatively large expansion coefficient. When the temperature changes, they are prone to dimensional changes, thus affecting the sealing effect.

The filled polytetrafluoroethylene (PTFE) oil seal replaces the lip-shaped rubber oil seal, which successfully solves the problem of water and oil leakage of the rubber skeleton oil seal.

1. Advantages of PTFE oil seal material

Polytetrafluoroethylene (PTFE), is a copolymer of tetrafluoroethylene monomer. It has the following advantages:

(1) Chemical stability: Almost all chemical resistance, strong acids, strong alkali or strong oxidants and organic solvents have no effect on it.

(2) Thermal stability: The pyrolysis temperature is above 400°C. Therefore, PTFE can work normally within the temperature range of -200°C to 300°C.

(3) Friction reduction: The friction coefficient of polytetrafluoroethylene material is extremely low, only 0.02, which is 1/40 of rubber.

(4) Self-lubricating property: The surface of PTFE material has outstanding self-lubricating properties, and almost all sticky substances cannot adhere to its surface.

2. PTFE oil seal filling modification

Pure PTFE is not wear-resistant. To make it practical, it must be filled and modified. We use two methods: one is inorganic filling modification, adding glass fiber, carbon fiber, graphite, molybdenum disulfide, etc. to PTFE. The other is organic filling modification, adding polyphenylene resin, Polyphenylene Sulfide, etc. to polytetrafluoroethylene (suitable for water purification, food, and pharmaceutical sealing). Through filling modification, the wear resistance of polytetrafluoroethylene is increased by 2000 times, and the rigidity and thermal conductivity are increased, allowing the oil seal to meet high life requirements.

3. PTFE sealing principle

The lip of the PTFE oil seal is drawn into a trumpet shape during processing. Since PTFE has the memory shrinkage ability after being drawn, the friction heat generated during work will cause the lip to shrink continuously, so the help of a spring is not needed. , it will hug the shaft tightly, prevent it from having any gap with the shaft surface, and compensate for wear.

Analysis of the application fields of polytetrafluoroethylene seals (also known as PTFE seals or PTFE oil seals)——

1. Chemical industry PTFE sealing ring:

PTFE seals have excellent chemical corrosion resistance and can work stably in highly corrosive media such as acids, alkalis, and salts. Therefore, it is widely used in the chemical industry for sealing various pipelines, pumps, valves and other equipment.

2. PTFE sealing ring in pharmaceutical industry:

PTFE seals are increasingly used in the pharmaceutical industry because they can resist erosion from various chemicals and high-temperature and high-pressure environments, while also meeting health standards and not contaminating drugs. In pharmaceutical equipment, medical equipment, etc., PTFE seals have been widely used.

3. Food industry PTFE sealing ring:

PTFE seals are also widely used in the food industry because of their excellent chemical resistance and hygienic properties. In food processing, storage, transportation, etc., PTFE seals can provide reliable sealing protection.

4. PTFE sealing rings in aerospace field:

PTFE seals are also widely used in the aerospace field because of their excellent high temperature resistance and chemical corrosion properties. In aerospace engines, spacecraft, aircraft, etc., PTFE seals can provide reliable sealing and protection to ensure the normal operation of equipment.

5. PTFE sealing rings in the field of mechanical equipment:

PTFE seals are also widely used in the field of mechanical equipment because it has a low friction coefficient and good wear resistance, which can improve the efficiency and life of mechanical equipment. In machine tools, hydraulic equipment, pumps, etc., PTFE seals can ensure the normal operation of the equipment.