System and method for improving the strength of railcar axles

Abstract

A method and system for increasing a railcar transportation axle's resistance to failure comprising treating at least one area of the axle to create a compressive surface layer on the component in order to reduce the occurrences of stress related surface defects.

What is claimed is: 
     
         1 . A method of improving a rail transportation axle's resistance to failure comprising the step of treating at least one area of the axle to create a compressive surface layer on the axle in areas of high stress resulting from tension during operation of the axle. 
     
     
         2 . The method of  claim 1 , where the step of treatment is performed using a shot-peening dispenser. 
     
     
         3 . The method of  claim 1 , where the step of treatment is performed using a roller burnishing tool. 
     
     
         4 . The method of  claim 1 , wherein the at least one area is an area of stress arising from a tension applied to the axle when performing its intended purpose. 
     
     
         5 . The method of  claim 2 , wherein the step of treatment comprises the steps of applying at least two applications of a shot-peening media wherein the media used in each application has different characteristics. 
     
     
         6 . The method of  claim 3 , where the method comprises steps of:
 securing the axle into a fixture that permits the axle to rotate axially;   causing the axle to rotate; and   applying the roller burnishing tool to a portion of the axle while the axle is rotating.   
     
     
         7 . The method of  claim 6 , wherein the roller burnishing tool comprises a spherical burnishing surface. 
     
     
         8 . The method of  claim 6 , wherein the roller burnishing tool comprises a cylindrical burnishing surface. 
     
     
         9 . The method of  claim 6 , wherein the surface of the axle has had a portion of its surface layer removed prior to the application of the roller burnishing tool. 
     
     
         10 . A treatment system for treating one or more areas of interest on a rail transportation axle, the system comprising:
 a work holding fixture adapted to affix the rail transportation axle in position for the application of a surface improvement treatment where the work holding fixture is configured to allow the axle to rotate; and   at least one surface treatment system applied to the rail transportation axle for improving the surface of the axle in areas where the axle is subject to tensile force during its intended use.   
     
     
         11 . The treatment system of  claim 10 , additionally comprising a part manipulating device which is a multi-axis robot. 
     
     
         12 . The treatment system of  claim 10 , wherein the surface treatment system is applied to the railcar axle using a multi-axis robot. 
     
     
         13 . The treatment system of  claim 10 , wherein the surface treatment system is a shot-peening device. 
     
     
         14 . The treatment system of  claim 13 , additionally comprising shot peening media, wherein the shot peening media comprises at least two varieties of shot peening media, each with different performance characteristics. 
     
     
         15 . The treatment system of  claim 10 , wherein the surface treatment system is a roller burnishing device. 
     
     
         16 . The treatment system of  claim 15 , wherein the roller burnishing device comprises a spherical contact surface applied to the axle. 
     
     
         17 . The treatment system of  claim 15 , wherein the roller burnishing device comprises a cylindrical contact surface applied to the axle. 
     
     
         18 . A treatment system for treating one or more areas of interest on a rail transportation axle, the system comprising:
 a conveyor for transporting a rail transportation axle along a path through a treatment area, the conveyor including a plurality of individual carriers that travel along a track through a treatment area, each carrier equipped with rotatable rail transportation axle retaining elements and means for rotating a retained axle for presentation to a treatment device;   at least one treatment device located in the treatment area; and   a part-manipulating device located in the treatment area, the part-manipulating device adapted to position the carriers in one or more orientations to at least the one treatment device.   
     
     
         19 . The system of  claim 18 , wherein the treatment device is a roller burnisher. 
     
     
         20 . The system of  claim 18 , wherein the treatment device is a shot-peening applicator.