Fixture and method of welding locomotive sills

Abstract

A welding fixture for use during welding of a web member to a flange member to produce a sill, includes an elongate bed having a pair of opposed longitudinal edge rails, and a plurality of clamp assemblies mounted at spaced intervals along each of the longitudinal edge rails. Each clamp assembly is selectively movable between an open configuration in which a welding head can move past the clamp assembly while welding the web member to the flange member, and a closed configuration in which the clamp assembly is operative to hold the web member and the flange member in a predetermined orientation relative to each other.

1 - 10 . (canceled) 
     
     
         11 . A method for preparing locomotive sills having at least one specified feature at a location on the sill defined relative to a predefined loaded configuration of the sill when incorporated into a locomotive, the method comprising:
 i. supplying a first elongated member and a second elongated member to be joined to one another to form said sill;   ii. forming at least one of the elongated members with a curvature to provide at least one of a required camber or sweep such that upon loading of the sill in use the elongated member attains said loaded configuration;   iii. establishing the position of each of the specified features on the at least one elongated member by compensating for the curvature of the member, and thereby detailing the first and second elongated members with specified features, and;   iv. subsequently assembling the sill by a method comprising:
 a) placing the elongated members on a welding fixture; and 
 b) welding the first and second elongated members together. 
   Whereby, upon loading of the sill, the final location of the specified feature corresponds to the predefined loaded configuration   
     
     
         12 . The method of  claim 11  wherein the members are secured to the welding fixture using a plurality of clamping assemblies. 
     
     
         13 . The method of  claim 12  wherein the specified feature is a plurality of holes. 
     
     
         14 . The method of  claim 13  wherein the placement of holes comprises:
 determining a line defined by a straightened edge of the member when the member is in the loaded configuration; 
 determining a linear deviation of the mid-point of the said edge of the member, relative to when the edge is straightened in the loaded configuration; 
 determining a first point positioned at one end of the said line; 
 determining a second point positioned at the other end of the said line; 
 determining a third point positioned at the linear deviation; 
 determining an arc using the first, second, and third point; 
 calculating the half-angle of the arc; 
 determining a datum edge spaced the half-angle from the midpoint of the arc; 
 determining coordinates for the holes using the datum edge; 
 assembling the coordinates into a dataset and storing them in a computing device; 
 using the computing device to transform the dataset into a set of commands for a cutting tool; and 
 commanding the cutting tool to cut the required holes into the member. 
 
     
     
         15 . A method for the placement of holes on a curved elongated member for a locomotive sill whereby the position of the holes are defined relative to a predefined loaded configuration of the sill when incorporated into a locomotive, the method comprising:
 determining a line defined by a straightened edge of the member when the member is in the loaded configuration;   determining a linear deviation of the mid-point of the said edge of the member, relative to when the edge is straightened in the loaded configuration;   determining a first point positioned at one end of the said line;   determining a second point positioned at the other end of the said line;   determining a third point positioned at the linear deviation;   determining an arc using the first, second, and third point;   calculating the half-angle of the arc;   determining a datum edge spaced the half-angle from the midpoint of the arc;   determining coordinates for the holes using the datum edge;   assembling the coordinates into a dataset and storing them in a computing device;   using the computing device to transform the dataset into a set of commands for a cutting tool; and   commanding the cutting tool to cut the required holes into the member.