Sewage flowmeter selection need to pay attention to what?

In the electromagnetic flowmeter installation and debugging stage there will be some failures, below, we will understand the specific causes of the failure at this stage and their elimination methods.

What are the problems encountered when electromagnetic flowmeters are used in paper mills

The reason why the measurement error is large is that the amount of oil and suspended matter in the water from the sewage station is high, and the treated sewage has a small amount of oil and suspended matter in the water, and the error of electromagnetic flowmeter measurement is also small.

Size DN3-DN3000mm
Nominal Pressure 0.6-1.6Mpa(2.5Mpa/4.0Mpa/6.4Mpa…Max 42Mpa)
Accuracy +/-0.5%(Standard) +/-0.3% or +/-0.2%(Optional)
Liner PTFE, Neoprene, Hard Rubber, EPDM, FEP, Polyurethane, PFA

The versatility of electromagnetic flowmeters is a testament to their robust performance across a wide range of conductive liquids. Whether dealing with water, acids, bases, or slurries, these flowmeters maintain their accuracy and reliability. This adaptability is particularly valuable in industries with varying fluid compositions, allowing for a single flowmeter type to be employed in diverse applications without sacrificing performance.

Protection Class: IP65(Standard); IP68(Optional for remote type)
Process Connection: Flange (Standard), Wafer, Thread, Tri-clamp etc (Optional)
Output Signal: 4-20mA/Pulse
Communication: RS485(Standard), HART(Optional),GPRS/GSM (Optional)
Power Supply: AC220V (can be used for AC85-250V)
DC24V (can be used for DC20-36V)
DC12V (optional), Battery Powered 3.6V (optional)
Power Consumption: <20W Alarm: Upper Limit Alarm / Lower Limit Alarm Self-diagnosis: Empty Pipe Alarm, Exciting Alarm Explosion Proof: ATEX

Electromagnetic flowmeter grounding problem

The installation direction of the electromagnetic flowmeter is not particularly strict requirements, generally horizontal, vertical or inclined can be unlimited. However, it must be reminded that in order to ensure that the pipeline is full of the measured medium, that is, the “full tube” state, it is recommended to install vertically, flow from bottom to bottom, especially for liquid-solid two-phase fluids, it must be installed vertically.

The electrode is the main part of the electromagnetic flowmeter used to measure the liquid flow, therefore, the choice of normal electrode material is directly related to the accuracy of the measurement and the price of the electromagnetic flowmeter.

The correct selection of electromagnetic flowmeter is the prerequisite to ensure the good use of electromagnetic flowmeter. What kind of electromagnetic flowmeter should be selected should be determined according to the physical and chemical properties of the measured body medium, so that the diameter of the electromagnetic flowmeter, flow range, lining material, electrode material and output current, etc., can adapt to the nature and flow requirements of the measured body.

The application of flowmeter in food processing is very extensive, mainly reflected in the following aspects:

Drainage flowmeter, sewage outfall flowmeter installation position

Another important requirement of the electromagnetic flowmeter: how to accurately select the lining material, the lining material of the electromagnetic flowmeter should be selected according to the erosion, wear and temperature of the measured medium.

The correct selection of electromagnetic flowmeter is the prerequisite to ensure the normal use of the instrument. The diameter, flow range, lining material, electrode material and output current of the electromagnetic flowmeter should be determined according to the physical and chemical properties of the measured flow medium, and can adapt to the field environment and meet the technical indicators and performance requirements.

Electromagnetic flowmeter is based on the principle of electromagnetic induction, through the electromotive force generated by the conductive fluid through the external magnetic field to measure the fluid flow meter. Electromagnetic flowmeter is widely used because of its high precision and good stability, so the choice of integrated or split electromagnetic flowmeter is particularly important.

The installation of the electromagnetic flowmeter depends on the requirements of the customer’s working conditions, and then select the type, and install it according to the instructions or the guidance of the flowmeter manufacturer’s staff. The following points need to be noted when installing the electromagnetic flowmeter:

In the use of electromagnetic flowmeter measurement, we often have to consider how to deal with the problem of receiving no signal or signal is too weak, we should look for reasons from the following possible problems:

We have introduced a lot of relevant information about electromagnetic flowmeters before, and today we mainly introduce several typical installation errors to help you avoid these problems.

One of the significant advantages of electromagnetic flowmeters is their high level of accuracy and reliability. With no moving parts in direct contact with the fluid, these devices experience minimal wear and tear, resulting in low maintenance requirements and increased longevity. Their versatility allows them to handle a broad spectrum of conductive liquids, from water and chemicals to slurries, making them suitable for a wide range of applications. Moreover, electromagnetic flowmeters are insensitive to changes in fluid properties, such as density, viscosity, and temperature, ensuring consistent and precise measurements across varying operating conditions.

Power Supply: AC220V (can be used for AC85-250V)
DC24V (can be used for DC20-36V)
DC12V (optional), Battery Powered 3.6V (optional)
Power Consumption: <20W Alarm: Upper Limit Alarm / Lower Limit Alarm Self-diagnosis: Empty Pipe Alarm, Exciting Alarm Explosion Proof: ATEX

The measurement of sewage by electromagnetic flowmeter generally does not require daily maintenance, but when the measured medium is easy to adhere to or scale the inner wall of the electrode and the measuring tube, it is necessary to regularly clean the inner wall of the measuring tube and the electrode, and be careful not to damage the flowmeter lining and the electrode.

Electromagnetic flowmeter, with high precision, long life characteristics, in chemical industry, environmental protection, metallurgy and other fields and industries have been applied.

Several factors can contribute to the inaccurate measurement of flow by electromagnetic flowmeters. These factors can vary depending on the specific application, installation conditions, and characteristics of the fluid being measured. Here are some common reasons for inaccurate flow measurement with electromagnetic flowmeters:

Electromagnetic flow meters operate based on a fundamental principle of electromagnetic induction, providing an accurate and reliable method for measuring the flow of conductive fluids. The working principle involves Faraday’s law of electromagnetic induction. As a conductive fluid flows through a pipe, it cuts across the magnetic field generated by coils or electrodes mounted on the flow meter. According to Faraday’s law, an electromotive force (EMF) is induced in the fluid perpendicular to both the magnetic field and the flow direction. The induced EMF is directly proportional to the flow velocity of the fluid.

Compared with other flow measuring instruments, electromagnetic flowmeters have the following outstanding advantages

Electromagnetic flowmeter, with high precision, long life characteristics, in chemical industry, environmental protection, metallurgy and other fields and industries have been applied. However, in the process of use, due to the influence of many factors, it is easy to cause the inaccurate measurement results of the electromagnetic flowmeter. So what are the reasons for the error of the electromagnetic flowmeter?

Electromagnetic flowmeters find versatile applications across various industries due to their precision and reliability in measuring fluid flow. One primary area of application is in water and wastewater management, where these flowmeters excel in accurately measuring the flow of water and other conductive fluids. Municipalities and water treatment plants utilize electromagnetic flowmeters to monitor water distribution networks, optimize usage, and ensure efficient wastewater processing.

Measuring Range： Max 15m/s
Conductivity： >5us/cm
Protection Class： IP65(Standard); IP68(Optional for remote type)
Process Connection： Flange (Standard), Wafer, Thread, Tri-clamp etc (Optional)
Output Signal： 4-20mA/Pulse
Communication： RS485(Standard), HART(Optional),GPRS/GSM (Optional)
Power Supply： AC220V (can be used for AC85-250V)
DC24V (can be used for DC20-36V)
DC12V (optional), Battery Powered 3.6V (optional)
Power Consumption： <20W Alarm： Upper Limit Alarm / Lower Limit Alarm Self-diagnosis： Empty Pipe Alarm, Exciting Alarm Explosion Proof： ATEX

Electromagnetic flowmeters exhibit remarkable performance even in challenging environmental conditions. Their construction materials are often chosen for their corrosion resistance, enabling these devices to withstand harsh chemicals and extreme temperatures. This robustness ensures continuous and reliable operation, making electromagnetic flowmeters suitable for demanding industrial applications where other flow measurement devices might struggle to perform consistently.

Size: DN3-DN3000mm
Nominal Pressure: 0.6-1.6Mpa(2.5Mpa/4.0Mpa/6.4Mpa… Max 42Mpa)
Accuracy: +/-0.5%(Standard) +/-0.3% or +/-0.2%(Optional)
Liner: PTFE, Neoprene, Hard Rubber, EPDM, FEP, Polyurethane, PFA
Electrode: SUS316L, Hastelloy B, Hastelloy C Titanium, Tantalum, Platinium-iridium
Structure Type: Integral type, remote type, submersible type, ex-proof type
Medium Temperature: -20~+60 degC(Integral type)
Remote type ( Neoprene ,Hard Rubber ,Polyurethane ,EPDM) -10~+80degC
Remote type(PTFE/PFA/FEP) -10~+160degC
Ambient Temperature: -20~+60deg C
Ambient Humidity: 5-100%RH(relative humidity)
Measuring Range: Max 15m/s
Conductivity: >5us/cm

The requirements of the straight tube section of the electromagnetic flowmeter are very important to ensure the accuracy and stability of the measurement results. The following is a detailed analysis of the requirements of the straight pipe section before and after the electromagnetic flowmeter:

In the field of industrial processes, electromagnetic flowmeters are extensively employed for measuring the flow of liquids such as chemicals, acids, and slurries. Their capability to handle corrosive fluids and resist wear makes them invaluable in industries like chemical manufacturing, pharmaceuticals, and food and beverage production. In these applications, electromagnetic flowmeters contribute to process optimization, ensuring precise control of fluid volumes and enhancing overall operational efficiency.

Size: DN3-DN3000mm
Nominal Pressure: 0.6-1.6Mpa(2.5Mpa/4.0Mpa/6.4Mpa…Max 42Mpa)
Accuracy: +/-0.5%(Standard) +/-0.3% or +/-0.2%(Optional)
Liner: PTFE, Neoprene, Hard Rubber, EPDM, FEP, Polyurethane, PFA
Electrode: SUS316L, Hastelloy B, Hastelloy C Titanium, Tantalum, Platinium-iridium
Structure Type: Integral type, remote type, submersible type, ex-proof type
Medium Temperature: -20~+60 degC(Integral type)
Remote type ( Neoprene ,Hard Rubber ,Polyurethane ,EPDM) -10~+80degC
Remote type(PTFE/PFA/FEP) -10~+160degC
Ambient Temperature: -20~+60deg C
Ambient Humidity: 5-100%RH(relative humidity)
Measuring Range： Max 15m/s
Conductivity： >5us/cm

Once the installation location is determined, the next step is preparing the piping system. Ensure that the pipeline is clean and free from debris that could interfere with the operation of the flowmeter. In some cases, straight pipe runs are recommended both upstream and downstream of the flowmeter to allow for proper fluid flow development and stabilization. This helps in achieving optimal measurement accuracy.

The electromagnetic flowmeter should be installed with the flow direction aligned with the arrow on the flowmeter body. Proper orientation ensures that the magnetic field generated by the flowmeter’s coils is perpendicular to the fluid flow, allowing for accurate measurements. Additionally, it is essential to properly ground the flowmeter to minimize electrical noise and interference, ensuring the stability of the measurement signals.

The installation process involves securely mounting the flowmeter on the piping system using appropriate brackets or supports. Care should be taken to align the flowmeter properly and tighten all connections to prevent leaks. Adequate sealing measures must be implemented to prevent ingress of moisture or contaminants into the flowmeter, which could adversely affect its performance.

Electromagnetic flowmeter at work requires that the measured medium must be ground potential, generally through the pipeline or flange ground, if the process pipe connected to the sensor relative to the measured medium is insulated (plastic pipe or pipe with an insulating lining), you must choose a grounding ring or sensor with a grounding electrode, so that the measured medium in the ground potential, easy to be ignored in the actual design and installation.