The domestic first set of positive pressure method standard table method gas flow standard device technical program developed by the Jiangsu Provincial Institute of Metrology was finalized by experts. Experts from universities and scientific research institutes such as Nanjing University of Aeronautics and Astronautics, Shanghai Institute of Industrial Automation Instrumentation, Zhejiang Province Metrology Institute highly affirmed the initiative of the device technology program, and put forward some suggestions for improvement.

The standard set of DN (15 ~ 150) mm standard gas flow rate device was commissioned by the Jiangsu Institute of Metrology, Nanjing Hong Kong and China Gas Company. The device used the high-precision gas turbine wheel flowmeter manufactured by the Netherlands company, Netherlands, as a standard meter, and used air as the medium to measure the meter under test under positive pressure conditions. Different from the commonly used gas flow metering device used in the negative pressure method, the device adopts a 2kPa to 10kPa adjustable positive pressure method for the first time, so that the measured flowmeter is closer to the actual state of use, and can effectively ensure the civilian diaphragm gas meter. Flow meter verification efficiency and accuracy. The device consists of a power system, a voltage regulator system, a constant temperature system, a standard meter, a flow control system, a return air circulation system, a clip table system, a computer measurement and control system, an auxiliary system, and application software. During the verification process, the device adopts constant temperature control on the verification medium. The gas continuously passes through the standard table and the tested flowmeter in the same time interval, and the measured flow error value of the detected flowmeter is obtained by comparing the flow values ​​of both outputs in real time. At the same time, the device can also receive pulse signal, photoelectric signal, current or voltage signal, switch contact signal, camera synchronous acquisition signal and other differently calibrated output signals; automatic control and manual control are adopted for different types of flowmeters. To achieve verification, the verification results are saved by the computer and various reports and certificates are automatically generated.

In the next step, the Metrology Institute of Jiangsu Province will further optimize the design plan and improve the technical details according to the opinions put forward by the experts and build a set of advanced standard gas flow standard devices with advanced technology and excellent quality.