scope:

This standard specifies a method of liquid flowrate measurement in closed conduits by measuring the mass of liquid delivered into a weighing tank in a known time interval. It deals in particular with the measuring apparatus, the procedure, the method for calculating the flow-rate and the uncertainties associated with the measurement. The method described may be applied to any liquid provided that its vapour pressure is such that any escape of liquid from the weighing tank by vaporazation is not sufficiet to affect the required measurement accuracy. Closed weighing tanks and their application to the flow measurement of liwquids of high vapour pressure are not considered in this standard. This standard does not cover the cases of corrosive or toxic liquids. Theoretically, there is no limit to the appliation of this method which is used generally in fixed laboratory installations only. However, for economic reasons, usual hydraulic laboratories using this method can produce flow-rate of 1,5 m3/s or less.