Investigation of two methods of volume measurements based on hydrostatic comparison method

摘要

Volume of weights is needed for air buoyancy correction, and measurement methods based on hydrostatic comparison are widely used to detect volume of weights. Several different hydrostatic comparison methods are given in OIML R111. In NIM, two different devices had already been set up to measure the volume of weights, and one is based on a mechanical balance, and another is based on an electrical balance. In this paper, two methods are discussed. Detailed measurement procedure and calculation are investigated, and uncertainty evaluation are also given. The consistence of two methods is also discussed based on an example.