WATER METERS TO BE MOUNTED IN THE PIPE CONDUITS OF A NOMINAL DIAMETER CLASS

摘要

The invention relates to water meters to be mounted in pipe conduits of a nominal diameter class and to a method for operating such water meters that function according to the Woltmann principle. The aim of the invention is to provide a device and a method which eliminates the need for calibration of every nominal diameter of the nominal diameter class, thereby avoiding the corresponding disadvantages. To this end, the water meters have, in the relevant location, namely in the annular channel (16) directly upstream of the impeller wheel (8), independent of the nominal diameter of the pipe conduit connected, a substantially rectangular speed distribution (19) with flow threads that are substantially parallel to the wall of the annular channel (16), said flow conditions being substantially identical at identical flow rates.