Electromagnetic flowmeter material selection guide- strong corrosion of the series
Electromagnetic flowmeter in the industry though often used to measure medium water, but the greatest advantages of electromagnetic is measured as long as the conductive liquid medium, it can satisfy the measurement requirements, and the application of measuring accuracy is higher than other meter, so when the need to measure is the acid, alkali medium, also using electromagnetic flowmeter is also a good choice. So, this article emphasizes the industry choice for everyone type electromagnetic flowmeter measurement of strongly corrosive acid, alkali in the electrodes and the lining material selection.
Recommend choosing electrode material:
First consider hartz alloy C, but its weak acid, alkali, corrosion resistant ability is good, for strong acid, alkali solution, has the ability of strong corrosion, so there will be under the condition of long-term corrosion, so it is not recommended to choose.
Second choice titanium, be self-healing thin oxide film layer, corrosion resistance is strong, the most suitable and chlorous acid, hypochlorous acid, fuming nitric acid, organic acid, alkali and corrosion, but not suitable for the pure reducing acid such as sulfuric acid, hydrochloric acid corrosion, if acid containing oxidant, corrosion is greatly reduced.
And then select the tantalum, is a very good acid corrosion of metal, it has excellent corrosion resistance ability, and glass are similar, except hydrofluoric acid, fuming sulfuric acid, alkali, most acids (including aqua regia, hydrochloric acid, sulfuric acid, nitric acid), poor wear resistance, electromagnetic flowmeter material often is applied to the electrode in the chemical industry.
The final choice is platinum-iridium alloy material, this is an excellent material, electrode is suitable for the vast majority of liquid medium, excellent resistance to chemical corrosion because of alloy composition containing platinum is bigger, iridium is mainly used to enhance the strength of the electrode, almost all the chemical corrosion of liquid can be used, but should not be the only measured with aqua regia and ammonium salt, and the material of platinum-iridium alloy electrode prices relative to the previous person is the most expensive.
Recommend choose lining material:
Material is the teflon, selection of the corrosive medium in this paper, we provide can choose this kind of material, it is more suitable for used in strong corrosive liquid, smooth, strong chemical resistance, boiling hydrochloric acid, sulfuric acid, nitric acid and aqua regia, strong alkali and a variety of organic solvents, not three chlorine fluoride, high temperature resistant, high velocity fluid fluoride, fluoride oxygen corrosion of liquid oxygen, ozone, poor abrasion resistance, adhesive ability is poorer, especially large-diameter price is more expensive.
Ceramic lining material, special industries (health), its acid and alkali resistance is strong, the electromagnetic flow sensor is mainly used in food industry, beverage industry, pharmaceutical industry, so the health conditions under the premise of the lining material ceramic is the best choice, but because of the ceramic lining of high technical requirements, the price is relatively high.
Above is based on all kinds of acid, alkali conditions, such as electromagnetic flowmeter lining and the selection of electrode material in detail. Hope to feature analysis in the process of selection of medium, strong corrosion in place right at the beginning of special material is a long-term, can be more economical.