NIST calibration services for pressure using piston gauge standards

Use of a higher order Heydemann–Welch model to characterize a controlled clearance piston gauge

“…In [4], p j was limited to 40% of p. One of NIST's controlledclearance piston gauges (designated as CCPG-2481, manufactured by Fluke Calibration 1 ) has been designed to operate at p j that can in some cases exceed 80% of p. Operating at high p j with CCPG-2481 has allowed improving the HW method through higher-order (non-linear) fits of the characterization parameters. 1 Certain commercial equipment, instruments, or materials are identified in this paper to foster understanding. Such identification does not imply recommendation or endorsement by NIST, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.…”

“…Many National Metrology Institutes, including the National Institute of Standards and Technology (NIST), use controlled-clearance piston gauges as primary standards for their hydraulic pressure scales [1][2][3]. In a controlled-clearance piston gauge, a ''jacket'' pressure, p j , is applied to the outer diameter of the cylinder, which controls the gap between the piston and cylinder [4].…”

Evaluation on the Consistency of Calibration Results Between Reference Standards of Pneumatic Pressure Balance Based on Non-Full Range Calibration

“…Typically, the calibration of pressure balance is performed with the full range calibration by using an appropriate or the best matches with the desired pressure range and accuracy of piston gauge standards (Olson, 2009). The full range calibration of pressure balance means that the direct comparison method between pressure balance to be calibrated (DUT) and the reference pressure balance (STD) is performed until the maximum pressure range of the DUT.…”