Roll forming process with heat source locations for forming a metal article with selective thermal forming/flanging/trimming operations

Abstract

A process and assembly for heat treating portions of a metal article, such as an advanced high strength (AHSS) steel. In an initial operation, the invention provides for positioning of heating elements along a travel path of an unreeled sheet of a metal. Following an initial heating, an initial bending or forming is employed by a first roll pass to bend or reform the article with the heated zones defining the bend axles or points within the article. Following the initial heating and bending operations, additional heating elements can located, such as against outer flange locations of the previously bent article for further bending in response to a downstream located roll pass operation, following which a subsequent trimming or final fabricating step is employed to complete the article.

1 . A process for heat treating portions of a metal article, comprising the steps:
 providing a roll of metal;   unreeling a continuous sheet of the metal;   positioning at least one heating element proximate the sheet prior to a first of a succession of roll pass operations;   heating the sheet prior to passing through the first roll pass operation; and   bending a cross section of the sheet to exhibit a tighter bend radii.   
     
     
         2 . The process as described in  claim 1 , further comprising advancing the sheet through a second roll pass operation following the first roll pass operation to conduct a further bending operation. 
     
     
         3 . The process as described in  claim 2 , further comprising positioning at least one additional heating element prior to a downstream located roll pass operation performed on the sheet in order to conduct a further bending operation. 
     
     
         4 . The process as described in  claim 1 , said step of positioning the heating elements further comprising locating the heating elements along bend axes of the roll formed article. 
     
     
         5 . The process as described in  claim 3 , further comprising each of a trimming and final fabricating step employed to complete the article. 
     
     
         6 . An assembly for forming a metal article, comprising:
 a coil steel roll is provided for feeding a continuous sheet of said roll through a series of passes corresponding to a series of roll forming operations for progressively shaping the steel sheet between initial planar and finished multi-sided cross sectional shapes;   one or more heat elements provided along a travel path of a sheet prior to a first of the roll passes, said heating elements being provided in a linearly arrayed fashion to align with one or more desired bend axes in order to form a finished product from the steel roll;   a further heating element located at a downstream location in order to apply additional targeted heating to one or more further selected bend or fold line locations of the article at an intermediate stage; and   the article being advanced through a further succeeding roll forming pass in which a final cross sectional shape is imparted to the linearly fed article to achieve the finished product.   
     
     
         7 . The assembly as described in  claim 6 , further comprising a second roll pass operation following the first roll pass operation for conducting a further bending operation on the continuous fed sheet. 
     
     
         8 . The assembly as described in  claim 7 , further comprising at least one additional heating element positioned at a downstream located roll pass operation performed on the sheet in order to conduct a further bending operation. 
     
     
         9 . The assembly as described in  claim 6 , said at least one additional heating element further comprising a pair of the heating elements located along bend axes of the roll formed article. 
     
     
         10 . The assembly as described in  claim 8 , further comprising each of a trimming and final fabricating step employed to complete the article.