Seven key points for the daily maintenance of gas turbine flowmeters

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　　The working principle of a gas turbine flow meter is as follows: The gas to be measured, as it enters the flow meter, is accelerated by a guide frame with a reduced cross-section; it then acts on the turbine blades through the inlet channel, causing the impeller to rotate. The impeller shaft is mounted on rolling bearings, and the speed of rotation of the impeller, which is proportional to the volume of the gas being measured, is transmitted after multiple stages of reduction to a counter or flow computer, thereby displaying the volume of the gas under actual conditions. The technician below will introduce the key points for the daily maintenance of gas turbine flowmeters:
Precautions for installing gas turbine flowmeters:
1. Before installation and use, follow the manufacturer’s instructions for setup.
2. After pipeline construction is complete, purge the pipeline and thoroughly remove debris such as weld slag and rust.
3. Horizontal installation is recommended.
4. Welding heat can completely damage the flowmeter; it is essential to avoid welding adjacent flanges while the flowmeter is in place. 　　Maintenance procedure for gas turbine flowmeters: 1. Before putting the gas turbine flowmeter into use, reset the instrument coefficients via the panel of the flow computer. 2. When starting up the gas turbine flowmeter, slowly open the inlet valve manually first; once the pipeline is completely filled with gas and pressure is balanced, then open the outlet valve manually to prevent damage to the turbine caused by sudden flow spikes. It is strictly prohibited to open or close the valves rapidly. 　　3. When putting the gas turbine flow meter into operation, it is required that the pressure regulation unit located downstream of the same pipeline has completed its pressure regulation, so as to avoid ice blockage; the pressure difference before and after the turbine flow meter should not be too large, nor should the flow velocity be too high. 　　4. Regularly clean, inspect, and recalibrate the flow meter, as well as inject lubricant periodically to ensure proper operation of the impeller; 5. Monitor the flow display on the flow computer, assess the flow conditions, and conduct inspections immediately in case of any abnormalities; 6. Keep the filters unobstructed. If the filter becomes clogged with impurities, this can be detected by the differential pressure value read from the differential pressure transmitters installed at the filter’s inlet and outlet; any blockage should be removed promptly. Under clean conditions, the differential pressure should be 0.15 bar; if it is 0.7 bar, the filter element must be cleaned and replaced. 7. If there are many impurities in the pipeline, causing abnormal operation of the flow meter’s turbine, the pipeline should be cleaned. The turbine of the flow meter should be removed, thoroughly cleaned using high-octane gasoline, and then reinstalled. 　　Flow measurement is one of the components of metrological science and technology, and it is closely related to the national economy, national defense construction, and scientific research. Doing this work well plays an important role in ensuring product quality, improving production efficiency, and promoting the development of science and technology. Especially in today’s era of energy crises and an increasing degree of automation in industrial production, the significance and role of flow meters in the national economy have become even more evident.