The most common cement bricks on the market are 240*115*53mm standard bricks, referred to as standard bricks; 240*115*90mm eight-hole bricks; 390*190*190mm hollow bricks and other specifications.
Cement brick standard (to produce wall brick 240×115×90mm as an example, strength grade 10MPA) Material: ordinary concrete or high permeability fly ash concrete
Specification
Apparent density: 2.10~2.30g/cm3
Tensile strength: 15.0Mpa
Ultimate elongation: 150%
PTFE is principally used as a gasket material because of it's capability to remain unaffected by the majority of chemicals used in industry. It is also classified, in most cases, as a food grade material, making it acceptable to both medical and food production industries. There are three basic types of PTFE Gasket materials. Virgin PTFE , filled PTFE and expanded PTFE .Features
Acid and alkali resistant
Chemical resistant
Has minimum friction coefficient of all know pure material
Non-viscous, no aging
Now molds can be made according to customers requirements.
Virgin PTFE is by far the least expensive of the three varieties, and is used in most general applications. Filled PTFE is a gasket material with a virgin PTFE base to which a substance is added during manufacture to improve the sealing characteristics of PTFE . This "filler" usually is glass or graphite particles although ceramics has sometimes been used. The resulting gasket material is strong, yet highly compressible with very good, though not universal, chemical resistance.
Expanded PTFE is virgin PTFE to which a stress resistance has been added by means of molecular rearrangement during manufacture. This process ensures that the molecular chains from which the PTFE is constructed, do not arrange themselves into set patterns. This means that expanded PTFE possesses no structural weakness (grain) and expands and contracts equally in all directions. Because no additives are required, expanded PTFE also possesses the unique chemical resistance of virgin PTFE.
PTFE Gasket
Glass Fiber PTFE Gasket,PTFE Seal Gasket ,White PTFE Gasket,Black PTFE Nylon Gasket
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