DIMENSIONAL CALIBRATION TECHNIQUES FOR PRESSURE BALANCES TO BE USED IN THE NEW DETERMINATION OF THE BOLTZMANN CONSTANT
A measurement procedure for the dimensional calibration of piston-cylinder type primary pressure standards is described. The piston-cylinder assemblies are intended to be used in a project for the re-determination of the Boltzmann constant. The measurement procedure includes optical and mechanical contacting, form and diameter measurement. A numerical post-processing procedure is applied to generate precise three-dimensional data sets of the piston-cylinder surfaces required for the effective area determination.