MEASURING AND REGULATING VALVE

摘要

A measuring and regulating valve assembly has a stop valve, preferably a butterfly valve, with a nominal passageway and moveable into open (90.degree.), closed (0.degree.) and intermediate positions by rotating a valve shaft. A measuring flange with connections for measuring a pressure differential across the flange is disposed upstream of the stop valve. A control box with an adjustable stop restricts the maximum opening angle of the stop valve in an accurately reproducible manner to any desired angle less than 90.degree.. The adjustable stop is moveable rectilinearly through a plane substantially perpendicular to the axis of the valve shaft while the maximum opening angle ie being set. Preferably, the distance between the valve and the measuring flange is at least 0.6 times the diameter of the nominal passageway.