Selection of Mud Flow Meter

Selection of Mud Flow MeterWidely used in sewage, fluorine chemical industry, production water, tap water industry, as well as pharmaceuticals, steel and many other fields. Due to its principle, it can only measure conductive liquids. Although it is much better in reliability and stability than other types of flow meters, customers still encounter some problems during actual use. Below, I will explain in detail the selection and installation of electromagnetic flow meters:

1、 Like other flow meters, although the measurement range ratio of electromagnetic flow meters is 30:1, which is higher than vortex flow meters and differential pressure flow meters, it is also limited. Many customers often compare it with water meters when ordering a meter, thinking that it can measure very low flow rates. Generally, it can only measure 0.1m/s. Below this flow rate, electromagnetic flow meters are difficult to measure correctly. So in the initial stage of ordering, it is necessary to clarify the flow range. When placing an order, it is not possible to order based on the original pipeline diameter, and the instrument diameter should be determined based on the actual flow rate.
2、 Like other flow meters, electromagnetic flow meters also have requirements for straight pipelines before and after installation, although the requirements are lower than other types of flow meters. However, the key point is to meet the requirement of full pipe and then full pipe. Insufficient flow can easily cause the flow meter to jump.
3、 Like other flow meters, electromagnetic flow meters also have protection levels. Generally, the protection level for integrated flow meters is IP65, and for split type flow meters (for sensors) it is IP68. If customers have requirements for the installation environment of the instrument and the installation location is in underground manholes or other humid places, it is recommended that customers choose split type flow meters. To avoid selecting the wrong one and causing damage to the instrument.
4、 Electromagnetic flow meters can measure corrosive liquids, but in the initial stage of ordering, customers need to provide the correct properties of other measuring media to avoid errors in electrode selection during selection, which may result in the sensor being scrapped during later use, causing inconvenience and economic losses to customers.
5、 Although electromagnetic flow meters have good reliability and are generally not damaged, due to their principle, the sensor electrode surface is always in contact with the liquid, and over time, the electrode surface is more susceptible to contamination. Therefore, in general, for electromagnetic flowmeters, if customers have the conditions to disassemble them, it is recommended to remove and clean the electrodes once every one to one and a half years to ensure the measurement accuracy of the entire flowmeter. Any instrument requires maintenance, and electromagnetic flow meters are no exception.
6、 When the main pipeline is a vertical pipeline, it is generally required that the water flow should be from bottom to top, and should not be from top to bottom as much as possible. The latter can easily cause significant fluctuations in traffic. In addition to filling the pipes, this is also very important for installation, followed by the distance between the front and rear straight pipes.
Selection of Mud Flow MeterChoose a place that is convenient for maintenance and activities. The flowmeter should be installed at the rear end of the water pump and must not be installed on the suction side; The valve should be installed on the downstream side of the flow.
1. Try to avoid ferromagnetic objects and specific equipment with strong electromagnetic fields (such as large motors, transformers, etc.) to prevent the magnetic field from affecting the working magnetic field and flow information of the sensor.
2. It should be installed in a dry and ventilated place as much as possible, and should not be installed in damp or water prone areas.
3. Avoid direct sunlight and rain as much as possible, and avoid environments with temperatures above 45 ℃ and relative humidity above 95%.
4. Choose a place that is easy to maintain and has convenient activities.
5. The mud flowmeter should be installed at the rear end of the water pump and must not be installed on the suction side; The valve should be installed on the downstream side of the flowmeter.

Mud flowmeter description:

The correct selection of mud flow meters is a prerequisite for ensuring the proper use of mud flow meters. The selection of the type of mud flowmeter should be based on the physical and chemical properties of the measured fluid medium, so that the diameter, flow range, lining material, electrode material, and output current of the mud flowmeter can adapt to the properties and flow requirements of the measured fluid.

● Measurable fluids
According to the working principle of the mud flowmeter, the fluid that can be used to measure flow rate with a mud flowmeter must be conductive. Strictly speaking, except for high-temperature fluids, any fluid with a conductivity greater than 5 μ/cm should be measured with a corresponding mud flowmeter. Therefore, non-conductive gases, steam, oils, acetone and other substances cannot be measured with a mud flowmeter.
Determination of sensor aperture
The flow rate of the flowmeter is within the range of 0.3-15m/s, and the diameter of the flowmeter can be selected to match the diameter of the user's pipeline.
When the flow rate is lower than 0.3m/s, locally increase the flow rate at the instrument location and use a contraction tube method:

● Selection of integrated or separated type
Integrated type: When the on-site environment is good, it is generally preferred to use an integrated type, that is, the sensor and converter are assembled into one.
Separated type: The sensor and converter are installed separately in different locations, and the separated type is generally selected when the following situations occur.
⑴ The ambient temperature or the radiation temperature on the surface of the flowmeter converter exceeds 60oC.
⑵ In situations where pipeline vibration is significant.
In situations where the aluminum casing of the sensor is severely corroded.
In situations where the on-site temperature is high or there are corrosive gases present.
The flowmeter is installed at high altitude or in places where it is inconvenient to debug it in parallel.
When ordering, the separation distance of the sensor converter should be specified, generally not exceeding 100m, and the converter should be wall mounted.

Technical parameters of mud flowmeter:
Caliber: DN6~DN600mm
Accuracy level: 0.3 level, 0.5 level
Range ratio: 1500:1
Measuring flow rate: 0.3~15m/s
Communication methods: RS232, RS485 Modbus, and HART (optional)
Connection method: flange
Power supply: 220VAC or 24VDC
Characteristics of Mud Flow Meter:
There are no movable parts or flow blocking components inside the pipeline, and there is almost no additional pressure loss during measurement.
The measurement results are independent of physical parameters such as flow velocity distribution, fluid pressure, temperature, density, viscosity, etc.
On site, the range can be modified online according to the actual needs of the user.
High definition backlit LCD display, fully Chinese menu operation, easy to use, simple to operate, easy to learn and understand.
Adopting SMD devices and surface mount technology, the circuit has high reliability.
Adopting a 16 bit embedded microprocessor, it has fast computing speed and high accuracy, programmable low-frequency rectangular wave excitation, which improves the stability of flow measurement and low power consumption.
Full digital processing, strong anti-interference ability, reliable measurement, high accuracy, and a flow measurement range of up to 150:1.
◇ Ultra low EM1 switching power supply, suitable for a wide range of power supply voltage changes, with good EMC resistance performance.
◇ There are three integrators inside that can display the forward cumulative and reverse cumulative values, as well as the difference cumulative value. There is also a non power down clock inside that can record 16 power down times.
◇ Equipped with RS485, RS232, Hart, and Modbus communication signal outputs.
◇ It has self checking and self judging functions.
Selection of flow range for mud flowmeter:

Note:
1. Selection of electrode and grounding ring materials
The material of the electrode should be selected based on the corrosiveness of the fluid being tested. Please refer to the relevant corrosion manual. For special fluids, tests should be conducted

◆ Description of lining materials for mud flowmeter
The lining material should be selected based on the corrosiveness, wear resistance, and temperature of the tested medium