的安装电磁流量度的正确安装对电磁流量计的正常运行极为重要，这里主要介绍电磁流量传感器和转换器的安装。 Installation of electromagnetic flowmeter The correct installation of the electromagnetic flow rate is extremely important for the normal operation of the electromagnetic flowmeter. Here we mainly introduce the installation of the electromagnetic flow sensor and converter.
The installation of electromagnetic flowmeter sensors should pay attention to the following issues:
First, the installation site of the ordinary electromagnetic flow sensor enclosure protection level is IP65 (GB4208 dust and splash-proof water level), the requirements for the installation site are:
1) When measuring mixed-phase fluid, choose a place that will not cause phase separation;
2) Select a place where no negative pressure will appear in the measuring tube;
3) Avoid installing near electric equipment such as electric motors and transformers to avoid electromagnetic field interference;
4) Avoid installing in places with strong corrosive gas;
5) The ambient temperature should generally be in the range of -25 ~ 60 ℃, and avoid direct sunlight as much as possible;
6) Install in a place without vibration or small vibration. If the vibration is too large, fixed support should be added to the pipe before and after the sensor.
7) The relative humidity of the environment should generally be in the range of 10% ~ 90%;
8) Avoid installation in a place where it can be directly exposed to rain or submerged by water. If the sensor's enclosure protection level is IP67 (dust-proof and water-proof) or IP68 (dust-proof and diving-proof), the last two items may not be required.
对表前直管段长度的要求比较低。 Second, the length of the straight pipe section The electromagnetic flowmeter has a lower requirement for the length of the straight pipe section before the meter . Generally, for 90 ° elbow, T-shaped tee, reducer, fully open valve and other flow resistance parts, away from the sensor electrode shaft
The core line (not the end face of the sensor inlet) should have a straight pipe length of 3-5D; for valves with different openings, a straight pipe length of 10D is required; after the sensor, there should generally be a straight pipe length of 2D. When the valve cannot be fully
When opening, if the valve's interception direction is installed at 45 ° with the sensor electrode axis, the additional error can be greatly reduced.
3. Installation position and flow direction The electromagnetic flow sensor can be installed horizontally, vertically or obliquely. For horizontal installation, the sensor electrode shaft must be placed horizontally.
This can prevent the electrodes from being insulated for a short time due to the air bubbles entrained in the fluid; it can also prevent the electrodes from being covered by the deposits in the fluid. The sensor should not be installed at the highest point to avoid the accumulation of air.
The highest position is a bad installation position and should be avoided.
When installed vertically, the flow direction should be upward, so that no flow or very low flow, the heavy solid particles entrained in the fluid will sink, and the lighter fatty substances will rise away from the sensor electrode area. Measuring mud
When liquid-solid two-phase flows such as slurry and ore slurry, vertical installation can avoid solid phase sensation precipitation and uneven wear of the sensor lining. At the exit of a downward pipe, a bad installation position should be avoided.
There should be a certain back pressure at the installation place of the sensor. The direct exhaustion of the sensor outlet may easily cause the liquid in the measuring tube to be not full. This is a bad installation position and should be avoided.
To prevent negative pressure in the sensor, the sensor should be installed behind the pump and not in front of the pump.
Fourth, install the bypass pipe In order to facilitate the inspection and adjustment of zero point when the liquid flow is stationary, small and medium pipe diameter should be installed as much as possible. When measuring fluids containing deposits, consider mounting methods that facilitate cleaning of the sensor.
必须单独接地，并使传感器和流体大约处于相同电位。 V. Grounding In order to make the measurement accurate and the electrode will not be corroded by current, the electromagnetic flow sensor must be grounded separately, and the sensor and the fluid should be at about the same potential. Separate electromagnetic flowmeter,
In principle, the ground should be on the sensor side, and the converter should be grounded at the same ground point. In most cases, the built-in reference electrode or metal tube of the sensor can ensure the allowed potential balance. Therefore, the built-in reference
The electrode and metal tube ground the fluid in the tube, and connect the grounding piece of the sensor to the ground wire.
If the sensor is installed on a pipeline with cathodic corrosion protection, in addition to grounding the sensor and the grounding ring together, a thick copper wire should also be used to bypass the sensor across the two flanges of the pipeline to make the cathodic protection current between the sensor and the sensor.