Collect. Czech. Chem. Commun. 1989, 54, 3025-3030

Automated low gas flow-rate calibrator

Stanislav Wičar, Martin Svozil and Pavel Šimík

Laboratorní přístroje, 162 03 Prague 6


A new method of the absolute low gas flow measurement was developed. The method is based on the comparison of the known rate of a piston movement in a calibrated cylinder with the measured gas flow rate. Due to its compensating character, the method is extremely sensitive, and the relative error is given merely by the sensitivity of determining the pressure difference between the cylinder and atmosphere. The method is absolute as the apparatus constant is determined by such operations as weighing and frequency measurement.