Material Structure Characteristics Of Fluorine-lined Stop Valve
Lined Globe Valve Materials
1. Polyperfluoroethylene FEP (F46)
Applicable media:
Any organic solvent or reagent, dilute or concentrated inorganic acid, alkali, ketone, aromatic hydrocarbon, chlorinated hydrocarbon, etc.
Using temperature:
-85~150
Features: Mechanical, electrical properties and chemical stability are basically the same as F4, but the outstanding advantages are high dynamic toughness, weather resistance and radiation.
2. Polytrifluoroethylene PCTEF (F3)
Applicable media:
Various organic solvents, inorganic corrosive liquid (oxidizing acid)
Using temperature: -195~120
Features: Heat resistance, electrical properties and chemical stability are second only to F4, mechanical strength, creep performance, hardness are better than F4
3. Polypropylene: RPP
Applicable media: Aqueous solutions of inorganic salts, dilute or concentrated solutions of inorganic acids and alkalis.
Operating temperature: -14~80
Features: One of the lighter plastics, its yield, tensile and compressive strength, hardness are better than low-pressure polyethylene, with outstanding rigidity, good heat resistance, easy molding, and low cost. After modification, it has better impact resistance, fluidity, and bending elasticity.
4. Polyvinyl fluoride: hard) PVC
Applicable media: water resistance, concentrated alkali, non-oxidizing acid, chain hydrocarbon, oil and ozone, etc.
Using temperature: 0-55
Features: high mechanical strength, excellent chemical stability and dielectric properties, good oil resistance and anti-aging properties, easy to weld
and bond, low price.
5. Polytetrafluoroethylene PTFE (F4)
Using medium: strong acid, strong alkali, strong oxidant, etc.
Using temperature: -200~180
Features: It has excellent chemical stability, high heat resistance, cold resistance, low friction coefficient, and is a self-lubricating material, but it has low mechanical properties, poor fluidity, and large thermal expansion.
Polyvinylidene fluoride PVDF (F2)
Used medium: Resistant to most chemicals and solvents,
Using temperature: -70~100
Features: The tensile strength and compression strength are better than F4, resistant to bending, weathering, radiation. Light and aging, etc., characterized by good toughness and easy molding.
6. Polyolefin: PO
Applicable medium: Acids, alkalis, salts of various concentrations and certain organic solvents.
Using temperature: -58~80
Features: It is an ideal anti-corrosion material and has been widely used in large-scale equipment and pipeline linings for rotational molding.
Structural characteristics of fluorine-lined stop valve
Compared with gate valves, fluorine-lined stop valves have a simpler structure and are easier to manufacture and maintain.
The sealing surface is not easy to wear and scratch, has good sealing and long service life.
The valve disc has a smaller stroke when opening and closing, the opening and closing time is shorter, and the valve height is smaller.
The valve disc and valve stem are designed as an integrated structure, with a compact structure and safe use.
There are three structural forms of fluorine-lined stop valves: straight-through type, direct-current type, and angle type, among which the straight-through type is commonly used. The angle type can be installed at the corner of the pipeline system, and the direct-current type has the smallest flow resistance among stop valves.
Pneumatic and electric devices are configured according to user needs to meet the needs of remote control and program control.
The lining material of the replacement parts can be applied to various media.
Application of fluorine-lined stop valve
It is suitable for various concentrations of aqua regia, sulfuric acid, hydrochloric acid and various organic acids, strong acids, and strong oxidants at temperatures from minus 50 degrees Celsius to 150 degrees Celsius. It is also suitable for pipelines with various concentrations of strong alkali organic solvents and other corrosive gases and liquid media.
