IC card gas meter

Since 2005, the popularity rate of urban gas has been increasing year by year. By 2009, it has reached 91.4%. According to the 12th Five Year Plan of national urban gas development, by the end of the 12th Five Year Plan, the urban gas popularization rate in China will reach more than 94%, the gas popularization rate in county towns and small towns will reach more than 65%, and the number of gas households will reach 200 million.
According to the forecast, from 2012 to 2015, the market scale of membrane gas meters in China will reach 2074, 2488, 2986 and 35.83 million units respectively, with a compound growth rate of 20% [2].
The gas meter has the same principle as the old locomotive. It works by the pressure of gas and pushes the roller counter to count. How to do it? The cylinder and piston mechanism in locomotive is greatly simplified. The cylinder is replaced by bellows and the piston is replaced by membrane. The so-called "air tight box" is made of two and a half thin film boxes, but it is made of two and a half air tight boxes.