No abstract

This paper covers the design and the operational and performance characteristics of a precision pressure generation system utilizing a controlled-clearance type of piston gage. Programmed computer outputs for generating precise pressures automatically in increments smaller than 1 psi over the entire system range have been used to eliminate computational requirements and to generate a large number of pressures rapidly. Piston fall rates have been controlled using constantly varying jacket pressures to maintain sensitivity and flotation requirements, and to keep wear down to a minimum. Experience regarding constancy of pressure output over a period of three years is covered. The amount of actual time in use for the system is well over a thousand hr.