| Zugriffsnummer | 27041 |
| Dokumenttyp | Konferenzartikel in Zeitschrift |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | Design and evaluation of pressure balances with 1 · 10-6 uncertainty for the Boltzmann constant project |
| Autor(in); Institution |
Sabuga, Wladimir; 3.3, Stoffeigenschaften und Druck, PTB-Braunschweig
Priruenrom, Tasanee; National Institute of Metrology (NIMT), Pathumthani, THAILAND
Haines, Rob; Fluke Calibration, Phoenix, AZ, USA
Bair, Michael; Fluke Calibration, Phoenix, AZ, USA
|
| Quelle/Jahr | Proceedings of the 5th CCM International Conference on Pressure and Vacuum Metrology and the 4th International Conference IMEKO TC 16. PTB-Mitteilungen: 121 (2011), 3, 256 - 259 |
| ISSN | 0030-834X |
| Verlag | Bremerhaven: Wirtschaftsverl. NW |
| Konferenzangaben | 5th CCM International Conference on Pressure and Vacuum Metrology and 4th International Conference IMEKO TC 16, Berlin, 02-05, May, 2011, Germany |
| Freie Schlagworte | pressure balance ; Boltzmann constant ; 1 ppm ; cross-float ; effective area ; piston-cylinder assembly |
| Zusammenfassung | In support of the project for determination of the Boltzmann constant by dielectric constant gas thermometry, a system of pressure balances has been designed and constructed with the goal of defining pressures in helium in gauge and absolute measurement modes up to 7 MPa with a relative standard uncertainty of 1∙106. The design addresses temperature stability, mass uncertainty, effective area and pressure distortion coefficient in particular. The system includes two pressure balance platforms, three 20 cm2 and three 2 cm2 piston-cylinder assemblies (PCAs), two 150 kg mass sets and automated mass handlers. The design of the PCAs was optimized to reduce pressure distortion coefficients and mounting induced deformations. In order to perform automated cross-floats with the pressure balances in gauge or absolute mode differential pressure cells (DPCs) were applied to indicate pressure equilibrium. The effective area ratios obtained from cross-floats for all possible combinations of PCAs are consistent within 0.96·10–6. Using dimensional measurements, the effective areas of the 20 cm2 and 2 cm2 PCAs were determined with relative standard uncertainties of 0.7·10–6 and 1·10–6, respectively. Based on the currently available dimensional and cross-float data the relative standard uncertainty of the absolute pressure of 7 MPa is equal to 2.1·10–6. |
