Patent ID: 7581663
Filing Date: 2009-09-01
Classification: B22D,C21C,F27D

Abstract:
1. A stopper rod system for use in a metallurgical vessel, comprising a stopper rod having a nose on one end thereof, and a nozzle having a bore therethrough, the bore having an internal surface, the stopper rod nose and the internal surface of the nozzle bore having a point of contact when the stopper rod system is in a closed position; wherein at least one of the stopper rod nose and the internal surface of the nozzle bore comprises a plurality of ripples that are arranged such that the size of a flow channel when the stopper rod system is in an open position discontinuously increases in size as a function of the distance downstream from the point of contact, wherein the size of the flow channel does not decrease downstream from the point of contact, and wherein the flow channel contains a single constriction.