Applications
The intelligent electromagnetic flowmeter is composed of two parts: the sensor and the converter. It works based on Faraday's law of electromagnetic induction and is used to measure the volumetric flow rate of conductive liquids, and is a velocity meter. In addition to measuring the volumetric flow rate of general conductive liquids, it can also be used to measure the volumetric flow rate of strong corrosive liquids such as strong acids and alkalis, and uniform liquid-solid two-phase suspended liquids such as mud, slurry, and pulp. It is widely used in petroleum, chemical, metallurgy, textile, papermaking, environmental protection, food and other industrial sectors and municipal management, water conservancy construction, river dredging and other fields of flow measurement.
Application of electromagnetic flow meter in sewage treatment plant
Application of electromagnetic flowmeter in paper industry
Application of electromagnetic flowmeter in metallurgical industry
Instrument characteristics
Measurements are not affected by changes in fluid density, viscosity, temperature, pressure, and conductivity.
There are no blocking flow components in the measuring pipe, no pressure loss, and the requirements of the straight pipe section are reduced. Uniquely adaptable to slurry measurement.
Reasonable selection of electrode and lining materials has good corrosion resistance and wear resistance.
Full digital quantity processing, strong anti-interference ability, reliable measurement, high accuracy, and wide flow measurement range.
Ultra-low EMI switching power supply, suitable for a wide range of power supply voltage changes, good EMI resistance.
It adopts a 16-bit embedded microprocessor, which has fast computing speed, high accuracy, low-frequency rectangular wave excitation, and programmable excitation frequency, which improves the stability of flow measurement and low power consumption.
It uses SMD devices and surface mount (SMT) technology to ensure high circuit reliability.
There are no moving parts in the pipe, no obstructive flow parts, and there is almost no additional pressure loss in the measurement.
The range can be modified online according to the actual needs of users on site.
High-definition backlit LCD display, full Chinese menu operation, easy to apply, simple to operate, easy to learn and understand.
Digital communication signal outputs such as RS485, RS232, Hart and Modbus Profibus-DP (optional).
It has self-test and self-diagnosis functions.
Hourly total recording function, record the total amount of traffic in hours, suitable for time-of-use metering system (optional)
There are three calculators inside that can display forward accumulation, reverse accumulation and difference accumulation respectively, and there is a power-down clock inside, which can record 16 power-down times (optional).
How it works:
According to the principle of Faraday electromagnetic induction, a pair of detection electrodes are installed on the tube wall perpendicular to the measuring pipe axis and the magnetic field line, when the conductive liquid moves along the measuring tube axis, the conductive liquid cuts the magnetic field line to generate an induced potential, which is detected by two detection electrodes, and the value is directly proportional to the flow rate, and its value is: E=B.V.E.K
式中： E－感应电势；
K-coefficients related to magnetic field distribution and axial length;
B-magnetic induction strength;
V - Average flow rate of conductive liquid;
D-electrode spacing; (Measure the diameter inside the tube)
Measurement schematic diagram of electromagnetic flowmeter
The sensor uses the induced potential E as a flow signal, transmits it to the converter, and after amplification, transformation filtering and other signal processing, the instantaneous flow rate and cumulative flow rate are displayed with a dot matrix liquid crystal with backlight. The converter has 4~20mA output, alarm output and frequency output, and is equipped with RS-485 and other communication interfaces, and supports HART and MODBUS protocols.
Technical parameters
Nominal Diameter (mm) (Special specifications can be customized) | Pipeline PTFE lining: DN10~DN600 | |
| Piped rubber lining: DN40~DN1200 | ||
| Flow direction: | Positive, negative, net flow | |
| Range ratio: | 150：1 | |
| Repeatability error: | ±0.1% of measured value | |
| Accuracy Class: | Pipe type: 0.5 level, 1.0 level | |
| Temperature of the medium to be measured: | Ordinary rubber lining: -20~+60°C | |
| High temperature rubber lining: -20~+90°C | ||
| PTFE lining: -30~+100°C | ||
| High-temperature PTFE lining: -20~+180°C | ||
Rated Working Pressure: (High voltage can be customized) | DN6-DN80:≤1.6MPa | |
| DN100-DN250:≤1.0MPa | ||
| DN300-DN1200:≤0.6MPa | ||
| Flow Rate Range: | 0.1－15m/s | |
| Conductivity Range: | The conductivity of the measured fluid ≥ 5μs/cm | |
| Current Output: | Load resistance | 0~10mA:0~1.5kΩ |
| 4~200mA:0~750kΩ | ||
| Digital Frequency Output: | The upper limit of the output frequency can be set in 1~5000HZ to set the open-circuit bidirectional output of the transistor collector with photoelectric isolation. The collector current is 250mA when the external power supply ≤ 35V on | |
| Power supply: | AC220V或DC24V | |
| The length of the straight pipe section is required | Upstream ≥ 5DN and downstream ≥ 2DN | |
| Connection: | Flange connections are used between the flow meter and the piping, and the size of the flange connection should comply with the GB11988 regulations | |
| Explosion-proof level: | mdIIBT4 | |
| Protection Level: | IP65, special customization up to IP68 | |
| Ambient Temperature: | －25～＋60℃ | |
| Relative Temperature: | 5%～95% | |
| Total Power Consumed: | Less than 20W | |
Instrument selection
1. Selection code:
| model | Description | |||||||||
| LDE — | □ | □ | -□ | □ | □ | □ | □ | □ | -□ | |
| Diameter | 10-2200mm | |||||||||
| Combination | L | Split type | ||||||||
| Electrode material | M | Stainless steel | ||||||||
| T | Tue (Tuetanium) | |||||||||
| D | Your(Yourntalum) | |||||||||
| H | Hastelloy | |||||||||
| P | Pt platinum | |||||||||
| N | Ni nickel | |||||||||
| Output method | 0 | No output | ||||||||
| 1 | 4-20mA/1-5KHz | |||||||||
| 2 | 4-20mA | |||||||||
| Lining material | X | rubber | ||||||||
| F | Teflon | |||||||||
| P | Polyethylene | |||||||||
| J | Polyurethane rubber | |||||||||
| Display in place | 0 | Not displayed in place | ||||||||
| 1 | Display in place | |||||||||
| Communication mode | 0 | No communication | ||||||||
| 1 | RS485 | |||||||||
| 2 | RS232 | |||||||||
| 3 | Mobdus | |||||||||
| 4 | Hart | |||||||||
| Grounding | 0 | No ground ring | ||||||||
| 1 | There is a grounding ring | |||||||||
| 2 | There is a grounding electrode | |||||||||
| Traffic cap | (n) | Upper flow rate (range) m3/h | ||||||||
Example: Choose a local display split electromagnetic flowmeter to measure sewage, the user pipeline is DN50, rubber material lining, stainless steel electrode, 4~20mA output, no communication, the upper limit flow rate is 30m3/h. The model should be: LDE-50L-M1X100-30
Selection of measurement ranges
| Inner Diameter (mm) | 10 | 15 | 20 | 25 | 32 | 40 | 50 | 65 |
| Qmin(m3/h) | 0.0283 | 0.0636 | 0.12 | 0.176 | 0.29 | 0.452 | 0.7 | 1.19 |
| Qmax（m3/h） | 4.24 | 9.54 | 16.96 | 26.5 | 43.42 | 67.85 | 106.0 | 179.0 |
| Inner Diameter (mm) | 80 | 100 | 125 | 150 | 200 | 250 | 300 | 350 |
| Qmin(m3/h) | 1.8 | 2.82 | 4.41 | 6.36 | 11.3 | 17.6 | 25.4 | 34.6 |
| Qmax（m3/h） | 271.0 | 424.0 | 662.0 | 954.0 | 1690 | 2650 | 3810 | 5190 |
| Inner Diameter (mm) | 400 | 450 | 500 | 550 | 600 | 700 | 800 | 900 |
| Qmin(m3/h) | 45.2 | 57.2 | 77.6 | 85.5 | 101.0 | 138.0 | 180.0 | 229.0 |
| Qmax（m3/h） | 6780 | 8570 | 10600 | 12800 | 15200 | 20700 | 27100 | 34300 |
| Inner Diameter (mm) | 1000 | 1100 | 1200 | 1400 | 1600 | 1800 | 2000 | 2200 |
| Qmin(m3/h) | 282.0 | 342.0 | 407.0 | 554.1 | 732.7 | 916.0 | 1131.0 | 1368.4 |
| Qmax（m3/h） | 42400 | 51300 | 61000 | 83121 | 108566 | 137404 | 169635 | 205258 |
Selection of electrode materials
The material of the electrode should be selected according to the corrosiveness of the measured fluid, please check the relevant manual, and the corrosive test should be done for special fluids
| Materials | Codename | Corrosion resistance |
| 316L stainless steel | V | 1. It is suitable for neutral solutions such as industrial and domestic water, raw water well water, and urban sewage 2. Weakly corrosive acids, alkalis, salt media such as carbonic acid, acetic acid, etc |
| Hastelloy C | HC | 1. It is suitable for oxidation-resistant acids, such as nitric acid, mixed acid, chromic acid and sulfuric acid mixture 2. Resistance to oxidizing salts or other oxidizing agents Corrosion in the environment, such as Fe and Cu 3. It has excellent corrosion resistance to seawater, alkali solutions and oxide solutions 4 Not applicable: hydrochloric acid |
| Hastelloy B | HB | 1. It has good corrosiveness to non-oxidizing acids, alkalis, salts such as sulfuric acid, phosphoric acid, and hydrofluoric acid 2 Not applicable: Nitric acid |
| Tuetanium | Tue | Resistant to seawater, various chlorides, hypochlorite and a variety of hydroxides corrosion |
| Yourntalum | Your | Except hydrofluoric acid, it is resistant to corrosion from almost all chemical media. But expensive |
| Platinum | Pt | Suitable for all acid-alkali salt solutions (fuming sulfuric acid and nitric acid) |
| Tungsten carbide | W | It has excellent wear resistance and is specially used in abrasive media such as slurry and pulp |
Choice of lining material
The lining material should be selected based on the corrosiveness, abrasiveness, and temperature of the medium being tested
| Lining material | Corrosion resistance | Operating temperature | Scope of application |
| Neoprene Ne | It is resistant to corrosion of general low concentrations of acid and alkali salts | -20～70℃ | Low concentration of acid and alkali salts in industrial water and sewage |
| Polyurethane rubber PO | It has excellent wear resistance, is specially used for strong abrasive slurry, and is not corrosion resistant | -10～60℃ | Liquids containing solid particles (cement slurry, slurry, etc.) |
| Polyperfluoroethylene propylene FEP | 1. Heat and corrosion resistance is comparable to PTFE 2. High mechanical strength and good wear resistance 3. The inner surface is smooth, not easy to adhere to the sediment 4. It has good negative pressure resistance and anti-vacuum effect | -40～180℃ | All fluids except strong abrasive media such as mortar. Like PTFE, it can be used in beverages and other media with hygiene requirements |
| PTFE | It can resist corrosion from almost all chemical media and has poor wear resistance | -40～180℃ | It cannot be used for negative pressure pipelines and abrasive fluids |
