Magnetic inducitve flowmeter common lining materials and their characteristics
Time: 2024-07-03
Magnetic inductive flowmeter is mainly composed of magnetic circuit system, electrode, converter, measuring tube and shell and other parts. According to Faraday's law of magnetic inductive induction, when the flowing conductive liquid cuts the magnetic line of force will produce an electric potential proportional to the speed. The role of the electrode in the magnetic inductive flowmeter is to measure this induced electromotive force.
Project Overview
In the magnetic inductive flowmeter measuring tube, only allows the electrode connected to the conductive liquid, the other parts need to be lined to achieve the insulating effect, in order to protect the magnetic inductive flowmeter work properly.
How do I select a liner for a magnetic inductive flow meter?
- 1. Chloroprene rubber (CR) main properties: oil resistance, solvent resistance, oxidation resistance, resistance to corrosion of general acids, alkalis, salts and other media; excellent elasticity, abrasion resistance, but poor cold resistance. Scope of application: for 0 ℃ ~ 80 ℃ non-strong acid, strong alkali, strong oxidizing medium; can measure sewage, mud.
- 2. Silicofluoroelastomer (FVMQ) main properties: good low temperature resistance, can still work normally at -55℃; outstanding heat resistance, can work for a long time at 180℃. Scope of application: applicable to non-wearing non-corrosive media from -25℃ to 150℃; applicable to high temperature fluid working conditions.
- 3. Polyurethane rubber (PU) main properties: excellent abrasion resistance, elasticity; poor resistance to acid and alkali. Scope of application: applicable to the medium of -25℃~60℃; can measure neutral and strong abrasion of mineral slurry, coal slurry, mud slurry and so on.
- 4. Main properties of Teflon (PFA): good hydrophobicity and non-adhesion, strong high temperature resistance; excellent corrosion resistance, resistant to strong acids, alkalis, organic solvents and various salt solutions; good negative pressure resistance, can be added inside the metal mesh to further improve the negative pressure resistance; poor abrasion resistance. Scope of application: suitable for -25℃~140℃ non-abrasive media and sanitary media.
- 5. Main properties of polyperfluoroethylene propylene (F46): hydrophobic and non-stick; corrosion resistance is second only to PFA; metal mesh can be added to improve the negative pressure resistance; wear resistance is poor. Scope of application: applicable to non-strong abrasive media and sanitary media from -25℃ to 100℃.
- 6. Polytetrafluoroethylene (PTEE) main properties: a more stable chemical properties of plastics, resistant to boiling hydrochloric acid, sulfuric acid, nitric acid and aqua regia, but also resistant to concentrated alkali and a variety of organic solvents; not resistant to chlorine trifluoride, high temperature oxygen trifluoride, high flow rate of liquid fluorine, liquid oxygen, ozone corrosion; poor abrasion resistance; poor resistance to negative pressure, prone to deformation of the lining or fracture, resulting in leakage of the electrode. Scope of application: for -25℃~140℃ media; concentrated acid, alkali and other strong corrosive media; sanitary media.
- 7. Ceramic (AL₂O₃) Main Properties: high abrasion resistance, high negative pressure resistance; excellent long-term operational stability, high accuracy; excellent corrosion resistance, can measure mixed acid, aqua regia; excellent heat resistance and resistance to cold and hot shock. Scope of application: chemical industry, mining industry, food industry.