Calibration Flow Meter - Weighing Method (2)

Static weighing

The principle of the flow-rate measurement method by static weighing (for schematic diagrams of typical installations, see figures 1 A, 1 B, 1 C) is :

ü                     to determine the initial mass of the tank plus any residual liquid;

ü                to divert the flow into the weighing tank (until it is considered to contain a sufficient quantity to                   attain the desired accuracy) by Operation of the diverter, which actuates a timer to measure the filling time;

ü                   to determine the final mass of the tank plus the liquid collected in it.

The flow-rate is then derived from the mass collected, the collection time and other data as discussed in clause 5 and annex A.

Figure IA - Diagram of an installation for calibration by weighing (static method, supply by a constant level head tank)

Figure 1B - Diagram of an installation for flow-rate measure by weighing

 (used for an hydraulic machine test; static method, supply by a constant level head tank) 

Figure 1C - Diagram of an installation for calibration by weighing

(static method, direct pumping supply)