System and method for thermal processing casting material

Abstract

A method for thermal processing rails including casting a rail from a metal, allowing the rail casting to cool to a temperature within a predetermined range, immediately placing the rail casting, when at the temperature, into a first chamber having gaseous nitrogen, cooling the rail casting to about −300 degrees using the gaseous nitrogen, allowing the rail casting to soak in a second chamber having liquid nitrogen and allowing the rail casting to reach room temperature.

What is claimed is: 
     
         1 . A method for thermal processing rails, comprising:
 casting a rail from a metal;   allowing the rail casting to cool to a temperature within a predetermined range;   immediately placing the rail casting, when at the temperature, into a first chamber having gaseous nitrogen;   cooling the rail casting to about −300 degrees using the gaseous nitrogen;   allowing the rail casting to soak in a second chamber having liquid nitrogen; and   allowing the rail casting to reach room temperature.   
     
     
         2 . The method of  claim 1 , wherein the metal is iron. 
     
     
         3 . The method of  claim 2 , wherein the metal is steel. 
     
     
         4 . A system for thermally processing a metal casting, comprising:
 a transporting means configured to move a metal casting; and   a plurality of chambers comprising:
 a first chamber configured to store gaseous nitrogen and configured to receive the metal casting; 
 a second chamber configured to store liquid nitrogen and configured to receive the metal casting; and 
 a third chamber configured to bring the casting material to room temperature. 
   
     
     
         5 . The system of  claim 4 , wherein the transporting means includes a conveyor belt. 
     
     
         6 . The system of  claim 5 , wherein the transporting means continuously moves the metal casting through the first chamber, the second chamber, and the third chamber.