Analysis of the possibility of an incorrect shift of the mechanical index of a diaphragm gas meter working under vibration

Abstract

The article discusses the operation of bellows gas meters, commonly used to measure household gas consumption. It was noted that their testing and certification scope covers laboratory conditions, including work in vibration-free conditions, while vibrations occur in actual situations. It should be noted that the presented analysis is part of analyzing illegal gas consumption – UAG (unaccounted for gas), which is the subject of scientific research both in Poland and globally. The Oil and Gas Institute itself states [1] that it has received approximately 1,400 expert opinions, in which the gas meter user indicated that the counter had been skipped, while laboratory tests of the gas meter did not confirm any irregularities. The author, therefore, addresses the topic by asking whether the design of bellows gas meters with a mechanical counter may contain a design defect that may cause the counter to skip and then “disappear”. As part of the research, an analysis was made of whether vibrations had any impact on the operation of the gas meter, and after confirming the implications, the counter was dismantled, and an attempt was made to determine the causes of the impact of vibrations. Finally, it was indicated what values of forces and acceleration are sufficient to cause measurement errors, and it was recommended that the construction of the counter be modified to prevent this phenomenon from occurring. The conclusions show that if the gas meter is used outside the scope of its certification, the counter may jump. Still, this jump will not leave any mechanical traces, and the gas meter may ultimately function appropriately after the vibrations stop.