Venturi Meter Constructions for Plastic Irrigation Pipelines

Venturi tubes or meters, represent one of the oldest and most reliable flow meters that can readily pass the debris frequently accompanying irrigation pipeline deliveries. Standard Venturi constructions, however, are beyond the economic range of interest for farm practice. These investigations of special Venturi meters constructed from plastic pipe fittings attempted to address these economic limitations, fouling problems and water management requirements. Thirty Venturi meters were constructed. They had a main pipe size 30 cm (12 in.) in diameter with a contraction to 20 cm (8 in.) in diameter in the meter throat. With proper technique, the several constructions duplicated calibrations to within about ±2%. They establish that individual calibrations are not required for effective applications in irrigation practice.