The metering of water flow in and out of waterworks and sewage treatment plants is the key measurement in the water industry. It is an important basis for enterprises to count major production and operation indicators such as output, production cost, pipe network leakage and energy consumption per unit, and it is also a metering link in the water industry. In and out, the selection of water flow meters is more critical, how to correctly choose flow meters and improve the level of measurement and detection is a very important work for enterprises, of which ultrasonic flow meters are very popular.
Compared with other fields, the flowmeter used in the import and export water flow measurement of waterworks and sewage treatment plants has its special requirements. First of all, the diameter of the flowmeter is relatively large, generally DN300mm-DN1000mm range. Secondly, the flow measurement value of water is large, generally thousands to tens of thousands of m3/h; In addition, in order to ensure that the requirements of supply and drainage trade measurement are met, the selected ultrasonic flowmeter requires high accuracy; Due to the large diameter of the flow meter and the limited installation position, the requirements for the straight pipe section cannot be too high. For the inlet and outlet water flow characteristics, we should pay attention to the following aspects when choosing ultrasonic flow timing:
Ultrasonic flowmeter
1. The large diameter of the process pipeline requires the pressure loss of the flow meter to be as small as possible. Generally, the method of local pipe reducing is not used to increase the flow rate.
2. For newly designed and installed pipelines, the appropriate flow rate is generally selected. Because the flow rate of the fluid is too low, the caliber of the flow meter is large, and the corresponding investment in the instrument is increased. The flow rate of the fluid is too high, which will cause the dynamic pressure loss and lead to the increase of operating costs, which is not economical, but the selection should leave a flow margin for the future expansion;
3. Due to the low flow rate of the fluid, dirt in the fluid, silt and scale will appear after a long time of operation, and so on, it is easy to deposit on the inner wall of the pipeline and the electrode. The cleaning of the contact part between the instrument and the fluid should be considered in the engineering design;
4. The measuring range of the instrument is large. Some water flow at night and during the day, winter and summer flow is very different, as many as several times, therefore, these water flowmeters require a particularly large range;
5. The protection level of the instrument is high. Large diameter pipelines are mostly buried in order to save investment and space, and in the north, it is also the need for anti-freezing. Therefore, split flow sensors are mostly installed in instrument Wells. Due to rain, wall leakage and pipe leakage and other reasons often cause the water level in the well to rise and flood the flow sensor, so the design should be estimated in this case, choose a submersible flow sensor, such as IP68 protection level. At the same time, the instrument well should be waterproofed.
6. Because the verification of large runoff meters is often difficult to disassemble, transport and install, and the process does not allow interruption and shutdown, it is hoped that the meters can be dry calibrated online.
Ultrasonic flowmeter
At present, the most important flow meters used in water plants, sewage treatment plants into and out of water flow metering are ultrasonic flow meters and electromagnetic flow meters, etc., and a small number of application plug-in flow meters, and a large number of updates to intelligent, high-precision, multi-functional flow meters. And has realized wired, bus type digital communication mode (such as MODBUS, PROFBUS, HART, etc.) and wireless communication mode to achieve remote monitoring, and traffic data far to the central control room and the company control room. The metering of water flow in and out of waterworks and sewage treatment plants is the key measurement in the water industry. It is an important basis for enterprises to count major production and operation indicators such as output, production cost, pipe network leakage and energy consumption per unit, and it is also a metering link in the water industry. In and out, the selection of water flow meters is more critical, how to correctly choose flow meters and improve the level of measurement and detection is a very important work for enterprises, of which ultrasonic flow meters are very popular.
Compared with other fields, the flowmeter used in the import and export water flow measurement of waterworks and sewage treatment plants has its special requirements. First of all, the diameter of the flowmeter is relatively large, generally DN300mm-DN1000mm range. Secondly, the flow measurement value of water is large, generally thousands to tens of thousands of m3/h; In addition, in order to ensure that the requirements of supply and drainage trade measurement are met, the selected ultrasonic flowmeter requires high accuracy; Due to the large diameter of the flow meter and the limited installation position, the requirements for the straight pipe section cannot be too high. For the inlet and outlet water flow characteristics, we should pay attention to the following aspects when choosing ultrasonic flow timing:
Ultrasonic flowmeter
1. The large diameter of the process pipeline requires the pressure loss of the flow meter to be as small as possible. Generally, the method of local pipe reducing is not used to increase the flow rate.
2. For newly designed and installed pipelines, the appropriate flow rate is generally selected. Because the flow rate of the fluid is too low, the caliber of the flow meter is large, and the corresponding investment in the instrument is increased. The flow rate of the fluid is too high, which will cause the dynamic pressure loss and lead to the increase of operating costs, which is not economical, but the selection should leave a flow margin for the future expansion;
3. Due to the low flow rate of the fluid, dirt in the fluid, silt and scale will appear after a long time of operation, and so on, it is easy to deposit on the inner wall of the pipeline and the electrode. The cleaning of the contact part between the instrument and the fluid should be considered in the engineering design;
4. The measuring range of the instrument is large. Some water flow at night and during the day, winter and summer flow is very different, as many as several times, therefore, these water flowmeters require a particularly large range;
5. The protection level of the instrument is high. Large diameter pipelines are mostly buried in order to save investment and space, and in the north, it is also the need for anti-freezing. Therefore, split flow sensors are mostly installed in instrument Wells. Due to rain, wall leakage and pipe leakage and other reasons often cause the water level in the well to rise and flood the flow sensor, so the design should be estimated in this case, choose a submersible flow sensor, such as IP68 protection level. At the same time, the instrument well should be waterproofed.
6. Because the verification of large runoff meters is often difficult to disassemble, transport and install, and the process does not allow interruption and shutdown, it is hoped that the meters can be dry calibrated online.
Ultrasonic flowmeter
At present, the most important flow meters used in water plants, sewage treatment plants into and out of water flow metering are ultrasonic flow meters and electromagnetic flow meters, etc., and a small number of application plug-in flow meters, and a large number of updates to intelligent, high-precision, multi-functional flow meters. And has realized wired, bus type digital communication mode (such as MODBUS, PROFBUS, HART, etc.) and wireless communication mode to achieve remote monitoring, and traffic data far to the central control room and the company control room.
Post time: Aug-14-2023