Pure polytetrafluoroethylene (PTFE) gaskets are also known as PTFE gaskets or Teflon gaskets in foreign countries. They are made by machining or cutting PTFE rods, pipes, and sheets into flat gaskets, V-shaped gaskets, piston rings, and ball valve gaskets. They can also be molded into shaped PTFE gaskets through high-temperature vulcanization. PTFE, due to its excellent corrosion resistance, aging resistance, insulation properties, and cleanliness, has been widely used in fields such as chemical, petroleum, pharmaceutical, and food industries. It is often referred to as the "king of plastics." PTFE has strong corrosion resistance and is only affected by a small amount of alkali metals and fluorine elements under high temperature and high-pressure conditions. It is non-absorbent, unaffected by oxygen and ultraviolet radiation, and has good weather resistance. After 3 years of exposure, its tensile strength remains basically unchanged, but the elongation decreases. Due to the tendency of PTFE to cold flow and creep under pressure and high temperature, it is particularly suitable for low and medium-temperature corrosive or non-contaminating sealing applications. PTFE can be processed into various shapes, and its mechanical strength remains stable between -100°C and 100°C. It can also be used in combination with other materials, such as PTFE-coated gaskets or PTFE tape, or as a coating for metal gaskets, such as metal-clad gaskets and metal corrugated gaskets.

Note: PTFE gaskets become brittle below -185°C and experience creep cracking above 200°C, so they are not suitable for extremely high temperatures. PTFE gaskets have a low thermal conductivity and a large cable expansion coefficient, which can cause cold flow under load. It is recommended to use them in applications with concave-convex surfaces, fully flat surfaces, and groove flanges under low-temperature and low-pressure conditions, with good water imprinting effects. Adding different fillers, such as glass fiber, graphite, molybdenum disulfide, bronze powder, etc., can improve the performance of PTFE gaskets.

Key Features:

1. Strong acid resistance. It can withstand almost all chemical media, except for molten alkali metals and elemental fluorine.
2. Excellent insulation performance, aging resistance, and weather resistance.
3. Low coefficient of friction, non-stickiness, and easy installation and disassembly.
4. Clean and suitable for sealing applications in non-contaminating areas such as food and pharmaceuticals.
5. High mechanical strength and easy machining into different sealing products.
6. Low linear expansion coefficient. When compressed and subjected to cold flow at high temperatures, it is prone to creep or stress relaxation. It is not suitable for high-temperature and high-pressure components.

PTFE gaskets are used in industries such as chemical, petrochemical, oil refining, chlor-alkali, acid production, phosphate fertilizers, pharmaceuticals, pesticides, chemical fibers, dyeing, coking, gas, organic synthesis, non-ferrous metal smelting, steel, nuclear energy, and the production of high-purity products (such as ion membrane electrolysis) and transportation. They are particularly important in industries that handle viscous materials, food, and beverage processing, with strict hygiene requirements.

Equipment applications: The sealing parts of flange joints, such as pipelines, valves, pumps, pressure vessels, heat exchangers, condensers, generators, air compressors, exhaust pipes, coolers, etc.