Slurry electromagnetic flowmeter

Slurry electromagnetic flowmeter

Measuring principle

The measuring principle of Slurry electromagnetic flowmeter is based on Faraday's law of electromagnetic induction. The explosion-proof electromagnetic flowmeter is composed of a sensor and a converter. The sensor is installed on the measuring pipe. The converter can be combined with the sensor and connected together, which is called an integrated electromagnetic flowmeter. The converter is installed within 30 meters or 100 meters from the sensor, and the two are connected by shielded cables, which is called a separate electromagnetic flowmeter.

Composition of Slurry electromagnetic flowmeter
The main components of Slurry electromagnetic flowmeter are: measuring pipe, electrode, excitation coil, iron core and yoke shell. Mud electromagnetic flowmeter is mainly used to measure the volume flow of conductive liquid and slurry in closed pipeline. For example, water, sewage, mud, pulp, various acid, alkali, salt solution, food slurry, etc., mud electromagnetic flowmeter is widely used in petroleum, chemical, metallurgical, textile, food, pharmaceutical, papermaking and other industries, as well as environmental protection, municipal management, water conservancy construction and other fields.

Features of Slurry electromagnetic flowmeter
1. The measurement is not affected by the changes of fluid density, viscosity, temperature, pressure and conductivity;
2. There are no flow blocking parts in the measuring pipe, no pressure loss, and the requirements for the straight pipe section are low;
3. Series nominal diameter DN15 ~ dn3000. There are many choices of sensor lining and electrode materials;
4. The converter adopts novel excitation mode, with low power consumption, stable zero point and high accuracy. The flow range can reach 1500:1;
5. The converter can be integrated or separated with the sensor;
6. The converter adopts 16 bit high-performance microprocessor, 2x16lcd display, convenient parameter setting and reliable programming;
7. The flowmeter is a two-way measurement system with three integrators installed inside: total forward, total reverse and total difference; It can display the flow rate and reverse flow rate, and has a variety of outputs: electricity
Current, pulse, digital communication, Hart;
8. The converter adopts surface mounting technology SMT, with self inspection and self diagnosis functions;
Selection of Slurry electromagnetic flowmeter

The measuring pipe has no obstruction, no moving parts and no pressure loss. The requirements for the straight pipe section are low. The enclosure protection grade: sensors IP65 and IP68 are optional (IP65: dust tight and water spray proof type, which allows the faucet to spray water to the instrument from any direction; IP68: Dust tight and submersible type, which can work in water for a long time). The measuring range (flow): 0-1m/s to 0-10m/s, with two-way flow and two-way total amount accumulation functions. The current and frequency have two-way output functions, In addition, there are plug-in, pipeline, battery powered, submersible, small caliber, anti-corrosion, high-voltage and other application modes.

Range confirmation of Slurry electromagnetic flowmeter
Generally, the measured medium flow rate of industrial electromagnetic flowmeter should be 2 ~ 4m/s. Under special circumstances, the minimum flow rate should not be less than 0.2m/s and the maximum should not be more than 8m/s. If the medium contains solid particles, the common flow rate shall be less than 3m/s to prevent excessive friction between the lining and the electrode; For viscous fluid, the flow rate can be greater than 2m/s. A larger flow rate is helpful to automatically eliminate the role of viscous substances attached to the electrode and improve the measurement accuracy.
Under the condition that the range Q has been determined, the diameter D of the flowmeter can be determined according to the range of the above flow rate V, and its value is calculated by the following formula:
Q=πD ² V/4
Q: Flow (㎡ /h) d: pipe inner diameter V: flow rate (m/h)
The range Q of the electromagnetic flowmeter shall be greater than the expected maximum flow value, while the normal flow value shall be slightly greater than 50% of the full scale of the flowmeter.

Selection of electrodes for mud electromagnetic flowmeter
1. stainless steel 0crl8nil2m02ti: used for weakly corrosive media such as industrial water, domestic water and sewage. It is suitable for industrial departments such as petroleum, chemical industry and steel, as well as municipal and environmental protection fields.
2. Hastelloy B: it has good corrosion resistance to hydrochloric acid of all concentrations below the boiling point, as well as non chlorinated acids, bases and non oxidizing salt solutions such as sulfuric acid, phosphoric acid, hydrofluoric acid and organic acid.
3. Hastelloy C: it can resist the corrosion of non oxidizing acids, such as nitric acid, mixed acid, or mixed medium of chromic acid and sulfuric acid, as well as the corrosion of oxidizing salts such as "Fe", Cu "or containing other oxidants, such as hypochlorite solution higher than normal temperature and seawater.
Electrode selection of pipeline electromagnetic flowmeter
4. titanium: it can resist the corrosion of seawater, various chlorides, hypochlorite, oxidizing acid (including fuming sulfuric acid), organic acid and alkali. It is not resistant to the corrosion of pure reducing acids (such as sulfuric acid and hydrochloric acid), but if the acid contains oxidants (such as nitric acid, fc++, cu++), the corrosion will be greatly reduced.
5. tantalum: it has excellent corrosion resistance and is very similar to glass. Except hydrofluoric acid, fuming sulfuric acid and alkali, it can resist the corrosion of almost all chemical media (including hydrochloric acid and nitric acid with boiling point and sulfuric acid below L50 ℃). It is easy to resist corrosion in alkali.
6. platinum / titanium alloy: it can withstand almost all chemical media, but it is not suitable for aqua regia and ammonium salt.
7. stainless steel coated with tungsten carbide: used for non corrosive and highly abrasive media.