1. Unreasonable pipeline design may lead to large measurement errors. For two parallel pipelines, when the main network uses gas, the manual valve of the branch network is closed. The flowmeter measures normally. When the branch network also uses gas, the manual valve is opened. Because part of the gas in the main pipeline is diverted by the branch pipe, the pressure in the main pipeline will drop, making the pressure in front of the flowmeter less than the pressure behind the meter, and the flowmeter will reverse the cumulative flow, resulting in double metering. To avoid this, a check valve must be installed in front of the 1 flowmeter.
2, high pressure metering low pressure gas. That is, the metering chamber is installed on the high-pressure pipeline, and then the pressure is regulated by the voltage regulator, and the gas users use the gas on the low-pressure pipeline. When the gas consumption of low-pressure pipeline users is small, according to the gas state equation, when the temperature is similar, the small flow of low-pressure pipeline will calculate the flow back to the high-pressure pipeline, and even this flow can not reach the initial flow of the flowmeter. Flowmeters don't count. So it will cause great measurement error.
3. Correct installation is helpful to improve the metering accuracy and prolong the service life of the flowmeter. When the flowmeter is installed on the pipeline, it should ensure that the threaded hole on the flowmeter body is aligned with the threaded hole of the pipeline flange, ensure the parallelism of the flange, and prevent the flowmeter from bearing other external forces, and prevent the flowmeter from being deformed and stuck. When opening the flowmeter, the front valve should be opened first, and then the rear valve should be opened slowly, so that the flowmeter can be started with pressure, and the flowmeter can be prevented from being stuck due to the impact deformation of the gas hammer effect on the flowmeter rotor.