APPLICATION OF MASS MEASUREMENT TECHNIQUE IN CALIBRATION AND CONTROL FOR GAS CYLINDERS

This paper deals with measurement and control of the standard gas cylinder. In CMS (Center of Measurement Standard), the mass measurement technology is used to calibrate the concentration of standard gas cylinders. This measurement method is based on the mass change of gas cylinder before and after filling. By using balance and calculating air buoyancy the mass difference of gas cylinder before and after filling could be obtained. In order to understand stability of the gas cylinder, we use statistical control techniques to monitor the change of concentration of the standard gas cylinders, to take immediate measures when the concentration of the standard gas cylinders is changed.