Characterization of the piston gauge to assess the suitability of its use with several working fluids up to 5 MPa

摘要

This paper describes the systematic studies carried out to characterize the controlled clearance piston gauge in the pneumatic pressure region up to 5.09 MPa by measuring its fall rate as a function of the jacket pressure (Pj) using different working fluids such as argon, nitrogen, helium, and hydrogen. It is also observed that a small ambient temperature fluctuation does not affect the overall uncertainty in the measured pressure. A relatively better reproducibility in the stall jacket pressure (Pz) values is obtained for helium and hydrogen as compared to that of argon and nitrogen; therefore it is shown that helium can also be used in addition to the commonly used nitrogen in the pneumatic pressure region. But the use of helium requires a higher value ofPjcompared to that of nitrogen in order to get a good floating condition of the gauge. In addition, a detailed study is reported of the effective area of the simple piston gauge with different working fluids used during the calibration.