Dimensional characterization of the effective area of pressure balance

Traditional way to establish the traceability of pressure balance to the basic SI units in the range near atmospheric pressure is the calibration of effective area against primary mercury manometers, which have currently the lowest measurement uncertainty in this range. The other possibility is dimensional characterization of the piston and cylinder which enables direct traceability to the unit of length. In the proposed study we will investigate the achievable measurement uncertainty of the dimensional characterization and determination of the effective area of the piston/cylinder unit of our pressure balance with a nominal diameter of 20 mm. Dimensional measurements will be performed in the Laboratory for Production Measurement (LTM) at Faculty of Mechanical Engineering, University of Maribor, which is a holder of Slovenian national standard of length. The final goal of the study is to establish the horizontal traceability to the Slovenian national standard of length of the effective area of the gas operated pressure balance in the Laboratory of Pressure Metrology at the Institute of Metals and Technology in Ljubljana.