The development of novel interchangeable pistons for pressure performance optimization in a gas-operated dead weight pressure balance

The texture of surfaces within a piston-cylinder assembly (PCA) can influence the pressure performance of gas-operated dead weight pressure balances (DWPBs). In order to systematically study this response, it has been necessary to design, develop and manufacture uniquely interchangeable 35 mm diameter PCAs for use in a novel hybrid gas-operated DWPB with high mechanical, thermal and pressure stability. This work reports the development of the PCAs and the validation of the DWPB design, allowing the performance characteristics of the interchangeable PCAs to be understood, in terms of variations of effective area calculations. This is achieved by investigating the pressure responses of the DWPBs by changing the speed and direction of rotation. The results demonstrate the stability of the gas-operated DWPB design when used in gauge mode, and importantly allow the verification of the performance of the interchangeable PCAs.