Manufacturer and model of sewage flow meter

Manufacturer and model of sewage flow meterProduct Overview:

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. Due to the many advantages of electromagnetic flowmeters, they are widely used for flow measurement in industrial sectors such as petroleum, chemical, synthetic, metallurgical, textile, papermaking, sugar production, water supply and drainage, environmental protection, food, municipal management, water conservancy construction, river dredging, and other fields.

Manufacturer and model of sewage flow meterMeasurement principle:

The working principle of electromagnetic flowmeter is based on Faraday's law of electromagnetic induction. The conductive medium inside the measuring tube is equivalent to a conductive metal rod in Faraday's test, with two electromagnetic coils at the upper and lower ends generating 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.

Sewage flow meter Industrial sewage flow meter Sewage flow meter Product features:
1. Measurement is not affected by changes in fluid density, viscosity, temperature, pressure, and conductivity;
2. Measure the flow components inside the tube, with no pressure loss and low requirements for straight pipe sections;
3. The nominal diameter of the series ranges from dn15 to dn3000. There are multiple options for sensor lining and electrode materials;
4. The converter adopts a novel excitation method, 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 from the sensor;
6. The converter adopts a 16 bit high-performance microprocessor, 2x16 LCD display, convenient parameter setting, and reliable programming;
7. The flowmeter is a bidirectional measurement system equipped with three integrators: forward total, reverse total, and differential total; Can display. Zhuang, reverse flow, and have multiple outputs: current, pulse, digital communication hart；
8. The converter adopts surface mount technology (SMT) and has self checking and self diagnostic functions.

Sewage flow meter Industrial sewage flow meter Sewage flow meter Main technical data:
Technical data of the whole machine and sensors

Instrument selection

Range confirmation

The flow rate of the measured medium in general industrial electromagnetic flowmeters should be between 2-4m/s. In special cases, the low flow rate should not be less than 0.2m/s and should not exceed 8m/s. If the medium contains solid particles, the commonly used flow rate should be less than 3m/s to prevent excessive friction between the lining and the electrode; For viscous fluids, the flow velocity can be chosen to be greater than 2m/s. A higher flow velocity helps to automatically eliminate the effect of viscous substances attached to the electrode, which is beneficial for improving measurement accuracy.

Under the condition that the range q has been determined, the size of the flowmeter diameter d can be determined based on the range of flow velocity v mentioned above, and its value can be calculated by the following formula:

q=πd2v/4
q: Flow rate (㎡/h) d: Inner diameter of pipeline v: Flow velocity (m/h)

The range q of the electromagnetic flowmeter should be greater than the expected flow value, while the normal flow value should be slightly greater than 50 of the flowmeter's full-scale scale.

Reference flow range of electromagnetic flowmeter

Quantity of sewage flow meters and connection type of sensors

• Circular shell integrated type: circular shell, the shell is directly connected with the sensor flange, explosion-proof design;

• Square shell integrated type: square shell, the shell is directly connected with the sensor flange;

• Square shell split type: wall mounted square shell, the converter is connected with the sensor cable.

1.5 Installation dimension diagram

Basic Circuit of Converter

The electromagnetic flowmeter converter provides stable excitation current to the excitation coil of the electromagnetic flow sensor. The preamplifier amplifies and converts the electromotive force induced by the sensor into standard current or frequency signals, which facilitates the display, control, and adjustment of flow. The circuit structure of the converter is shown in Figure 2-1.

Installation:

(1) Sensors and converters are packaged as a complete set, used together, and cannot be replaced at will.
(2) The usage condition is that the liquid flowing through the measuring pipeline must be in a fully filled state, otherwise it will affect the measurement accuracy. The installation position of the sensor should be preferably on a vertical pipeline, and the liquid inside the vertical pipeline must flow from bottom to top.
(3) It cannot be installed on the horizontal section of the process pipeline, as the highest point of the pipeline is prone to gas accumulation.
(4) Installed on horizontal or inclined process pipelines, the upstream straight pipe section is generally not less than 5D, and the downstream straight pipe section is generally not less than 2D. D is the inner diameter of the pipeline.
(5) The measuring tube is lined with anti-corrosion material and cannot be operated under negative pressure or installed on the pump suction pipe.
(6) The installation location should be far away from strong magnetic fields, and there should be no power equipment or magnetic starters near the installation location.
(7) When installing on horizontal or inclined process pipelines, the two detection electrodes should be in a horizontal position and should not be directly above or below the process pipeline.
(8) Good grounding is necessary to reduce the introduction of interference signals.

Precautions for installation before wiring

The replacement and related operations of internal circuit boards and other components must be carried out by professional engineers or technicians.

Before opening the shell cover, ensure that the equipment is powered off for at least 10 minutes. The opening of the shell cover must be carried out by professional engineers or technicians.

Explosion proof converters must be transferred to a safe area for maintenance, disassembly, and reassembly.

The converter circuit board components contain sensitive components that may be damaged by static electricity. Be careful during operation to avoid direct contact with electronic components or circuit patterns on the circuit board, and take corresponding anti-static measures if necessary.

Installation:

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 filled with liquid;
There should be a minimum of 5 * D (D is the inner diameter of the flowmeter) straight pipe section in front of the electromagnetic flowmeter, and a minimum of 3 * D (D is the inner diameter of the flowmeter) straight pipe section behind it;
The direction of fluid flow and 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 the cleaning and maintenance of the flowmeter in the future, a bypass pipeline should be installed.