Introduction of Common Nonmetallic Materials for Valves

1) Buna-N: NBR
It is an excellent universal rubber material, suitable for water, gas, oil and grease, gasoline (except gasoline with additives), alcohol and glycol, liquefied petroleum gas, propane and butane, fuel oil and many other media. At the same time, it also has good wear resistance and deformation resistance.
2) EPDM
The rated temperature range of EPDM valve seat is - 28 ℃ ~ 120 ℃. E. It can be widely used in HVAC industry, water, phosphate, alcohol, glycol, etc. EPDM seats are not recommended for use in hydrocarbon organic solvents and oils, chlorinated hydrocarbons, turpentine, or other petroleum oils.
3) PTFE: polytetrafluoroethylene

The rated temperature range of PTFE valve seat is - 32 ℃ ~ 200 ℃. Excellent high temperature resistance and chemical corrosion resistance. Polytetrafluoroethylene has high density, excellent impermeability, and can also prevent the corrosion of most chemical media.

4) Reinforced polytetrafluoroethylene rtfe
Rtfe is a modifier of PTFE. In order to improve the wear resistance of PTFE, some wear-resistant materials such as glass fiber, carbon fiber, graphite, molybdenum disulfide, bronze powder and some organic compounds can be added to form network nodes in the layered structure of PTFE, so as to improve the stiffness, thermal conductivity, creep resistance and wear resistance.
5) Fluororubber
The rated temperature of fluororubber seat is - 18 ℃ ~ 150 ℃. This material has high temperature resistance and excellent chemical corrosion resistance. It is suitable for hydrocarbon products, low concentration and high concentration mineral acids, but cannot be used in steam medium and water (poor water resistance).
6) UHMWPE
The rated temperature range of UHMWPE valve seat is - 32 ℃ ~ 88 ℃. This material has better low temperature resistance than PTFE, but still has excellent chemical resistance. UHMWPE also has good wear resistance and corrosion resistance, which can be used in high wear resistance occasions.
7) Silicon copper rubber
Silicon copper rubber is a kind of polymer with organic group and its main chain is composed of silicon oxygen atom. The rated temperature range is - 100 ℃ ~ 300 ℃. It has good heat resistance and temperature resistance, excellent electrical insulation performance and great chemical inertia. Suitable for organic acid and low concentration inorganic acid, dilute alkali and concentrated alkali. Disadvantages: low mechanical strength. Post vulcanization is required.

8) Graphite
It has unique physical and chemical properties such as high temperature resistance, oxidation resistance, corrosion resistance, thermal shock resistance, high strength, good toughness, high self-lubricating strength, strong thermal conductivity and conductivity. It has special oxidation resistance, self lubrication and plasticity at high temperature, and good conductivity, heat conduction and adhesion. It can be used as filler or performance improver for rubber, plastics and various composite materials to improve the wear resistance, compression resistance or conductivity of materials. Graphite is usually used to make valve gasket, packing and seat.