wet gas flowmeter(drum gas flowmeter, wet drum gas flowmeter)

Applications & User Benefits
Wet-test (drum-type) gas flow meters are used universally to measure and record gas volume and gas flow rate for many industrial, petroleum and chemical processes; environmental; pilot plant or test; controlled chamber; laboratory and research applications
Wet-test meters consistently provide the highest accuracy and precision even at the lowest gas flows with inert or the most aggressive gases
Measurement Principle.
Wet-test gas meters function upon the principle of positive displacement. The sample gas stream rotates a measuring drum within a packing fluid, usually water or low viscous "white" (clear) oil. A needle-dial and counting mechanism, coupled to the rotating drum,records the volume of gas flow as it sequentially fills and empties from the drum's rigid, fixed volume measuring chambers....