Method and Apparatus for Galvanizing an Elongated Object

Abstract

A method and apparatus for galvanizing an elongated object, such as, but not limited to, a metal strip, wire, or rod, using gaseous nitrogen, a mixture of gaseous and liquid nitrogen, and combinations thereof is described herein.

1 . An apparatus for processing an elongated object comprising a molten coating, comprising:
 a nozzle comprising: a nozzle opening; an inner chamber defining a first volume wherein the elongated object passes therethrough; an outer chamber defining a second volume that is in fluid communication with a nitrogen source wherein gaseous nitrogen passes through the second volume at a pressure and a temperature and exits proximal to the nozzle opening and contacts the elongated object; and   a concept pipe comprising: an porous inner chamber defining a third volume; an outer chamber defining a fourth volume wherein the fourth volume is in fluid communication with one or more inputs for a nitrogen mixture comprising gaseous and liquid nitrogen; and a temperature sensor to monitor a temperature of the nitrogen mixture, wherein the temperature sensor is in electrical communication with a programmable logic controller.   
     
     
         2 . The apparatus of  claim 1 , wherein the gaseous nitrogen passes through the second volume at a flow rate from about 5 to about 30 m 3 /h. 
     
     
         3 . The apparatus of  claim 1 , wherein the gaseous nitrogen exits proximal to the nozzle opening via an adjustable split opening having a length dx. 
     
     
         4 . The apparatus of  claim 3 , wherein dx is from about 0.01 to about 12 mm. 
     
     
         5 . The apparatus of  claim 1 , wherein the molten coating comprises zinc. 
     
     
         6 . The apparatus of  claim 1 , further comprising a blending pipe that combines the gaseous nitrogen and the liquid nitrogen to form the nitrogen mixture and provides the nitrogen mixture to the outer chamber of the concept pipe. 
     
     
         7 . The apparatus of  claim 6 , wherein the gaseous nitrogen is supplied to the blending pipe via a gaseous nitrogen line and the liquid nitrogen is supplied to the blending pipe via a liquid nitrogen line having a valve therein. 
     
     
         8 . A method for processing an elongated object comprising a molten coating comprising:
 passing a the elongated object through a nozzle configured to direct gaseous nitrogen at the surface of the object and remove excess coating from the object; and   passing the elongated object through a concept pipe configured to rapidly cool the elongated object and solidify the coating;   wherein the nozzle comprises a nozzle opening; an inner chamber defining a first volume wherein the elongated object passes therethrough; an outer chamber defining a second volume that is in fluid communication with a nitrogen source wherein gaseous nitrogen passes through the second volume at a pressure and a temperature and exits proximal to the nozzle opening and contacts the elongated object; and   wherein the concept pipe comprises an porous inner chamber defining a third volume; an outer chamber defining a fourth volume wherein the fourth volume is in fluid communication with one or more inputs for a nitrogen mixture comprising gaseous and liquid nitrogen; and a temperature sensor to monitor a temperature of the nitrogen mixture, wherein the temperature sensor is in electrical communication with a programmable logic controller.   
     
     
         9 . The method of  claim 8 , wherein the gaseous nitrogen exits proximal to the nozzle opening via an adjustable split opening having a length dx. 
     
     
         10 . The method of  claim 9 , further comprising adjusting the split opening to a length dx from about 0.1 to about 12 mm. 
     
     
         11 . The method of  claim 8 , further comprising:
 blending the gaseous nitrogen and the liquid nitrogen in a blending pipe to form the nitrogen mixture; and   supplying the nitrogen mixture to the outer chamber of the concept pipe.   
     
     
         12 . The method of  claim 11 , further comprising supplied gaseous nitrogen to the blending pipe via a gaseous nitrogen line, supplying liquid nitrogen to the blending pipe via a liquid nitrogen line having a valve therein, and adjusting the temperature of the nitrogen mixture supplied to the outer chamber of the concept pipe by opening or closing the valve in the liquid nitrogen line.