Intelligent sewage flow meter

Manufacturer's price:

Overview of Intelligent Sewage Flow Meter:

An electromagnetic flowmeter consists of two parts: a sensor and a converter. It works based on Faraday's law of electromagnetic induction and is used to measure the volumetric flow rate of conductive liquids with a conductivity greater than 5 μ S/cm. It is an inductive instrument for measuring the volumetric flow rate of conductive media. 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, as well as homogeneous liquid-solid two-phase suspensions such as mud, slurry, and pulp.

The electromagnetic flowmeter series is an induction type instrument that measures the volumetric flow rate of the conductive medium inside the museum based on Faraday's law of electromagnetic induction. It uses embedded microcontroller technology to achieve digital excitation, and adopts CAN on-site president on the electromagnetic flowmeter, which has reached the domestic level of technology. Electromagnetic flow meters can not only meet on-site display requirements, but also output 4-20mA current signals for recording, regulation, and control purposes. They have been widely used in industrial technology and management departments such as chemical, environmental protection, metallurgy, pharmaceuticals, papermaking, and water supply and drainage.
The KM-LDE series electromagnetic flowmeter can not only measure the flow rate of general conductive liquids, but also measure the volumetric flow rate of liquid-solid two-phase flow, high viscosity liquid flow, and salt, strong acid, and strong alkali liquids.

Working principle of intelligent sewage flowmeter:

The working principle of electromagnetic flowmeter is based on Faraday's law of electromagnetic induction. In an electromagnetic flowmeter, the conductive medium inside the measuring tube is equivalent to a conductive metal rod in Faraday's test, and the two electromagnetic coils at the upper and lower ends generate a constant magnetic field. When a conductive medium flows through, an induced voltage is generated. The induced voltage generated by measuring the two electrodes inside the pipeline. The measuring pipeline achieves electromagnetic isolation from the fluid and measuring electrode through non-conductive lining (rubber, Teflon, etc.), as shown in the figure.

Advantages and unique selling points of intelligent sewage flow meters:

1. The coil, an important component of the sensor, has been optimized through rigorous real current testing to ensure the measurement accuracy of the product

2. The signal electrode undergoes thorough electrostatic shielding treatment to ensure that small signals are not interfered by the coil and to guarantee measurement accuracy at low flow rates

3. The coil is isolated from the outside world to ensure its long-term insulation strength, which in turn guarantees the long-term measurement accuracy of the sensor

4. All welding processes of the sensor are carried out using argon arc welding technology. Although the cost is high, it can ensure the reliability of welding (welding is the main production process of the sensor), especially the welding process after installing the coil. Using argon arc welding technology can ensure that the installed coil is not damaged

5. Adopting a grounding electrode structure to form a balanced electrode plane ensures that the entire process of measuring the average speed is limited to the balanced electrode plane, which can effectively eliminate electrical noise interference and provide measurement results

6. Adopt customized double-layer shielded cables

7. Programmable low-frequency rectangular wave excitation improves the stability of flow measurement and reduces power loss

8. High frequency excitation is used for measuring special media (such as slurry) to eliminate clutter interference

9. Adopting a 16 bit embedded microprocessor, it has fast computing speed and high accuracy

10. All digital processing, strong anti-interference ability, reliable measurement, high accuracy

11. Ultra low EMI switching power supply, suitable for a wide range of power supply voltage changes, with good EMC resistance performance

12. Complete all functional designs with a single circuit board, using SMD devices and surface mount SMT (SMT) technology for high circuit reliability

13. High definition backlit Chinese LCD display, displaying cumulative flow rate, instantaneous flow rate, flow percentage, etc

14. Menu operation, easy to use, simple to operate, easy to learn and understand

15. Bidirectional measurement system, with three integrators inside that can display forward cumulative quantity, reverse cumulative quantity, and differential cumulative quantity respectively

16. Equipped with self checking and self diagnostic functions, and displayed on the screen

17. Unique lightning protection design

Anatomy diagram of electromagnetic flowmeter:

Key points for selecting intelligent sewage flow meters:

Electromagnetic flow meters have a wide range of applications. Large caliber instruments are commonly used in water supply and drainage engineering, while small and medium-sized instruments are commonly used in solid-liquid two-phase difficult to measure fluids or high demand places, such as measuring pulp and black liquor in the paper industry, slurry in the non-ferrous metallurgy industry, coal slurry in the coal preparation plant, highly corrosive liquids in the chemical industry, and controlling and monitoring cooling water in blast furnace tuyere in the steel industry. Flow measurement and control of long-distance pipeline coal hydraulic transportation. Small caliber and micro caliber are commonly used in places with hygiene requirements such as the pharmaceutical industry, food industry, and biotechnology.

1. Choose the appropriate type based on the characteristics of integrated and separated electromagnetic flow meters. The installation and wiring of the integrated electromagnetic flowmeter are convenient, with moderate accuracy, and should not be installed below the ground to prevent the converter from being submerged in water. The separated electromagnetic flowmeter has a high degree of accuracy, and the converter and sensor are installed in different locations, making it more suitable for situations with poor on-site environment (such as hazardous, toxic, and easily flooded places). However, the installation and wiring are strict, otherwise interference signals may be introduced.

2. Choose the appropriate electrode form. For media that do not produce crystals, scars, or contaminate electrodes, standard electrodes can be used. Otherwise, knife type cleaning electrodes or electrodes with cleaning connection devices can be used. For sludge testing, replaceable electrodes can also be used.

3. Select electrode materials based on the corrosiveness of the tested medium.

Electrode selection:

4. Select lining materials based on the corrosiveness, wear resistance, and temperature of the tested medium.

5. Protection level of electromagnetic flowmeter. According to the national standard GB4208-1984, which is approximately equivalent to the International Electrotechnical Commission IEC standard (IEC529-7B), the standard for the protection level of the enclosure is IP65, which is a waterproof type that allows the faucet to spray water on the instrument from any direction, with a spray pressure of 30Kpa. The water output is 0.75m3/h, and the distance between the water spray port and the instrument is 3m. IP67 is a waterproof type, which means that the instrument can be completely immersed in water, and the high point should be at least 3750px underwater for at least 30 minutes. IP68 is a submersible type that can work underwater for a long time. According to the above regulations, instruments that are prone to flooding when installed underground should be rated IP68, while instruments installed above ground should be rated IP65.

6. Select grounding based on the insulation of the connecting instrument pipeline.

7. Select the nominal pressure of the electromagnetic flowmeter based on the high pressure of the tested medium. For flow measurements with medium pressures of 10MPa, 16MPa, 25MPa, and 32MPa, high-pressure electromagnetic flow meters should be selected. Its * * * large diameter is 100mm.

Technical parameters of intelligent sewage flowmeter:
Nominal diameter series DN (mm)
Pipeline PTFE lining: 10, 15, 20, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600
Pipeline rubber lining: 40, 50, 65, 80, 100, 125, 150, 200, 300, 350, 400, 500, 600, 800, 1000, 1200
Flow direction: positive and negative net flow. Range ratio: 150:1. Repeatability error: ± 0.1% of the measured value
Grade: 0.5, 1.0 (pipeline type)
Temperature of the tested medium: ordinary rubber lining: -20 ° C? ＋60℃
High temperature rubber lining: -20? ＋90℃
PTFE lining: -30? ＋100℃
High temperature PTFE lining: -30 ° C? +180 ℃.
Rated working pressure: Pipeline type: DN6? DN80≤1.6Mpa，DN100? DN250≤1.0Mpa，DN300? DN1200≤0.6Mpa.
Flow measurement range: What is the flow velocity range corresponding to the flow measurement range of 0.1? 15m/s
Conductivity range: The conductivity of the measured fluid is ≥ 5us/cm (integrated type), and most media composed of water have a conductivity of 200 μ m? Electromagnetic flow meters can be used to measure the flow rate within the range of 800 μ s/cm.
Current output: 0? At 10mA, the load resistance is 0? 1.5kΩ；4? At 20mA, the load resistance is 0? 750kΩ
Digital frequency output: The upper limit of the output frequency can be 1? Set the transistor collector with photoelectric isolation to open circuit bidirectional output within 5000Hz. When the external power supply is ≤ 35V and conducting, the collector current is 250mA
Power supply: 85? 265V，45? 63Hz.
Straight pipe length: Pipeline type: upstream ≥ 5DN, downstream ≥ 2DN
Connection method: The flowmeter and piping are connected by flanges, and the flange connection size should comply with the provisions of GB11988.
Explosion proof mark: mdIIBT4
Environmental temperature: -25? 60℃
Relative humidity: 5%? 95%
Total power consumption: less than 20 watts.

Installation of intelligent sewage flowmeter:

1. Electromagnetic flow meters should be installed at the lower and vertically upward positions of horizontal pipelines, avoiding installation at the highest points and vertically downward positions of pipelines;

2. The electromagnetic flowmeter should be installed at the rising point of the pipeline;

3. When installing an open discharge pipeline, it should be installed at the lower part of the pipeline;

4. If the pipeline drop exceeds 5m, install an exhaust valve downstream of the sensor;

5. Electromagnetic flow meters should be installed with control valves and shut-off valves downstream of the sensor, rather than upstream of the sensor;

6. Sensors cannot be installed at the inlet and outlet of the pump, they should be installed at the outlet of the pump;

7. The method of installing electromagnetic flowmeter in the measuring well;

Figure 7 Remarks: 1. Inlet 2. Overflow pipe 3 Inlet grille 4. Cleaning hole 5. Flow meter 6. Short pipe 7. Outlet 8. Discharge valve

How to choose the installation node correctly:
Choosing the correct installation point and installing the flow meter correctly are both very important steps. If there is a mistake in the installation process, it can affect the measurement accuracy in mild cases, the service life of the flow meter in severe cases, and even damage the flow meter.
Special attention should be paid when selecting the installation location:

The axis of the non measuring electrode must be approximately horizontal;

The measuring pipeline must be completely filled with liquid;
There should be at least a 5 * D (D is the inner diameter of the flowmeter) straight pipe section in front of the electromagnetic flowmeter, and at least a 3 * D (D is the inner diameter of the flowmeter) straight pipe section behind it;
The flow direction of the fluid is consistent with the arrow direction of the flowmeter;
Vacuum inside the pipeline can damage the lining of the flowmeter, so special attention should be paid;
There should be no strong electromagnetic field near the electromagnetic flowmeter;
There should be ample space near the electromagnetic flowmeter for installation and maintenance;
If there is vibration in the measuring pipeline, there should be fixed supports on both sides of the flowmeter to measure mixed liquids of different media. The distance between the mixing point and the flowmeter should be at least 30 × D (D mortar flowmeter inner diameter) to facilitate future cleaning and maintenance of the flowmeter,

A bypass pipeline should be installed;