IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Vacuum Science & Technology Thursday Sessions
       Session VST1-ThP

Paper VST1-ThP5
Primary and Secondary Vacuum Standards Based on Piston-cylinder Technique

Thursday, November 1, 2001, 5:30 pm, Room 134/135

Session: Pressure Measurement & Calibration Poster Session
Presenter: J. Tesar, Czech Metrology Institute, Czech Republic
Authors: J. Tesar, Czech Metrology Institute, Czech Republic
D. Prazak, Czech Metrology Institute, Czech Republic
Correspondent: Click to Email
In the last years there were developed vacuum standards based on the piston principle with several construction designs. They can be utilised both in primary and in secondary metrology of vacuum. Covered ranges start at atmospheric pressure and reach the tenths of pascal. The attainable accuracy of top standards is fully comparable with other physical principles (mercury columns, static expansion, CDG). The first part of this paper will briefly summarize the most important construction designs, including ranges and attainable uncertainties. The second part of presentation will describe basic primary methods of calculation of effective area from dimensional measurement for classical, non-rotating, divider and conical design of primary piston standards of vacuum. In the third part the basic methods of secondary traceability will be shown: direct comparison with a liquid column standard, direct comparison with a static expansion system and three types of cross-floating comparisons in absolute pressure mode. Description of every method will be supplemented by a typical example from CMI praxis including full uncertainty budget.