Influence of liquid media separators on pressure calibrations and high-pressure experiments

This study quantitatively explores the influence of liquid media separators on pressure calibration results. When different liquids need to be used in standard and test pressure gauges, according to customer requirements or research objectives, it is common to incorporate a liquid media separator into the system to avoid contamination. However, the separator may cause a slight pressure difference between the two liquids due to the deformation of a separation diaphragm, affecting calibration results. We investigated the influence on calibration results for three types of liquid media separators—using a diaphragm, a plastic tube, or bellows. The influence on calibration results varies with pressure, and also depends on the separation mechanism. We also assessed the sensitivity of the separators, confirming that pressure changes as small as approximately 10 −6 can be transmitted. Based on these evaluations, the separator can be appropriately utilized for precise pressure calibrations and high-pressure experiments.