G0500502 Development of liquid micro-flow calibration facility

Abstract

A liquid low-flow calibration rig has been developed, which is consisted of a syringe pump and a gravimetric weighing tank system. A flowmeter is calibrated using the syringe pump to overcome issues on the low-flow rate and on the standing method. Calibration flow rate range of this one syringe pump is from 0.3 mL/min〜1000 mL/min (0.02 L/h to 60 L/h). For this purpose the syringe pump system was designed employing a servo-motor, a precise ball screw and a linear encoder. The syringe pump has been calibrated using the weighing tank at all flow rate range to check and extract latent problems in the whole calibration system. The weighing tank system has been improved to reduce influence of evaporation and outlet tube contact. The syringe pulse factors have been calibrated in all flow rates with light oil and industrial gasoline and they all agreed within ±0.02%. Preliminary expanded uncertainties of the low-flow rig have been estimated to be 0.066% for mass flow and 0.070% for volumetric flow.