Electromagnetic flowmeter is an instrument that uses the principle of electromagnetic induction to measure the flow of conductive fluid based on the electromotive force induced when the conductive fluid passes through an external magnetic field.
So how to choose the inner lining and electrode material?
Lining Material Selection
■ Neoprene (CR):
A polymer formed by emulsion polymerization of chloroprene monomer. This rubber molecule contains chlorine atoms, so compared with other general-purpose rubber: It has excellent anti-oxidation, anti-ozone, non-flammable, self-extinguishing after fire, oil resistance, solvent resistance, acid and alkali resistance, and aging and gas resistance. Good tightness and other advantages.
✔ It is suitable for flow measurement of tap water, industrial water, sea water and other media.
■ Polyurethane rubber (PU):
It is polymerized by polyester (or polyether) and diisocyanamide lipid compound. It has the advantages of high hardness, good strength, high elasticity, high wear resistance, tear resistance, aging resistance, ozone resistance, radiation resistance and good electrical conductivity.
✔ It is suitable for flow measurement of slurry media such as pulp and ore pulp.
■ Polytetrafluoroethylene ( P4-PTFE )
It is a polymer prepared by polymerization of tetrafluoroethylene as a monomer. White waxy, translucent, heat resistance, cold resistance, can be used in -180 ~ 260°C long-term. This material has the characteristics of acid and alkali resistance, resistance to various organic solvents, resistance to boiling hydrochloric acid, sulfuric acid, aqua regia, concentrated alkali corrosion.
✔ Can be used for corrosive acid and alkali salt liquid.
■ Polyperfluoroethylene propylene ( F46-FEP )
It has excellent chemical stability and outstanding radiation resistance, as well as non-flammability, good electrical and mechanical properties. Its chemical properties are equivalent to polytetrafluoroethylene, with strong compressive and tensile strength is better than polytetrafluoroethylene.
✔ Can be used for corrosive acid and alkali salt liquid.
■ Copolymer of tetrafluoroethylene and perfluorocarbon via vinyl ether ( PFA )
The lining material for electromagnetic flowmeter has the same chemical properties as F46 and better tensile strength than F46.
✔ Can be used for corrosive acid and alkali salt liquid.
Electrode Material Selection
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316L |
It is suitable for domestic sewage, industrial sewage, well water, urban sewage, etc., and weakly corrosive acid-base salt solutions. |
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Hastelloy (HB) |
Suitable for non-oxidizing acids such as hydrochloric acid (concentration less than 10%). Sodium hydroxide (concentration less than 50%) sodium hydroxide alkali solution of all concentrations. Phosphoric acid or organic acid, etc., but nitric acid is not suitable. |
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Hastelloy (HC) |
Mixed acid and mixed solution of chromic acid and sulfuric acid. Oxidizing salts such as Fe+++, Cu++, seawater, phosphoric acid, organic acids, etc., but not suitable for hydrochloric acid. |
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Titanium (Ti) |
Applicable to chlorides (such as sodium chloride/magnesium chloride/calcium chloride/ferric chloride/ammonium chloride/aluminum chloride, etc.), salts (such as sodium salt, ammonium salt, hypofluorite, potassium salt, seawater) , nitric acid (but not including fuming nitric acid), alkalis with concentration ≤50% at room temperature (potassium hydroxide, sodium hydroxide, barium hydroxide, etc.) but not applicable to: hydrochloric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, etc. |
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Tantalum electrode (Ta) |
Suitable for hydrochloric acid (concentration ≤ 40%), dilute sulfuric acid and concentrated sulfuric acid (excluding fuming nitric acid). Applicable to chlorine dioxide, ferric chloride, hypofluorous acid, hydrobromic acid, sodium cyanide, lead acetate, nitric acid (including fuming nitric acid) and aqua regia whose temperature is lower than 80°C. But this electrode material is not suitable for alkali, hydrofluoric acid, water. |
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Platinum electrode (Pt) |
Applicable to almost all acid-base salt solutions (including fuming nitric acid, fuming sulfuric acid), not applicable to: aqua regia, ammonia salt, hydrogen peroxide, concentrated hydrochloric acid (>15%). |
The above content is for reference only, please refer to the actual test. Of course, you can also consult us. We will provide you with some suggestions.
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Post time: Jan-05-2023