Pitot-Static Tube System to Measure Discharges from Wells

Pumps are widely used to lift water into canals, and usually spill directly into the canal. Upstream pipe fittings frequently produce a distorted flow profile that is detrimental to the proper installation and operation of common pipe meters. Thus, meter calibration may be necessary when the pipe length upstream of the meter is less than recommended. Meter calibrations under field conditions can be difficult and expensive. A simple pitot tube system that can be clamped to the outlet of the pump discharge pipe was built and tested for measuring and calibrating pump discharges under field conditions. It is used to detect the velocity at several points across the pipe diameter; distorted profiles can be measured. Using this information, the meter technician can determine whether a correction in the meter coefficient will suffice and if flow conditioning equipment is working effectively. The system can be constructed using common shop techniques and standard small pipe fittings. Most previous pitot systems required special ports in the pipe or used special concentric tube constructions that are difficult to build.