Process and production line for forming objects

Abstract

The present invention relates to a process for forming a metal component (20), the process comprising the steps of heating a metal blank (20) coated with a protective layer; cooling said metal blank (20) in a confined space (14), said cooling involving cooling by means of a gas, the gas being cooled by heat exchange with a cooling surface of a heat sink (22) inside said confined space (14), wherein a low frequency sound wave is provided into said confined space (14) in order to improve heat exchange both between the gas and a cooling surface of the at least one heat sink (22), and between the gas and the metal component (20), wherein the heated coated blank is cooled to a temperature below the melting point of the protective layer, and forming the coated blank to a component. The invention also relates to a production line for performing the process.

1 . A process for forming a metal component, the process comprising the steps of
 heating a metal blank coated with a protective layer;   cooling said metal blank in a confined space, said cooling involving cooling by means of a gas, the gas being cooled by heat exchange with a cooling surface of a heat sink inside said confined space, wherein a low frequency sound wave is provided into said confined space in order to improve heat exchange both between the gas and a cooling surface of the at least one heat sink, and between the gas and the metal component,   wherein the heated coated blank is cooled to a temperature below the melting point of the protective layer, and   forming the coated blank to a component.   
     
     
         2 . The process according to  claim 1 , wherein the protective layer comprises zinc. 
     
     
         3 . The process according to  claim 1 , wherein the protective layer comprises aluminium. 
     
     
         4 . The process according to  claim 3 , wherein the protective layer further comprises silicon. 
     
     
         5 . The process according to  claim 1 , wherein the heated coated component is cooled to about 550° C. 
     
     
         6 . The process according to  claim 1 , wherein the forming step comprises a number of sub-forming steps up to finalised form of component. 
     
     
         7 . The process according to  claim 6 , wherein the sub-forming steps also comprise cutting and/or punching of the blank. 
     
     
         8 . The process according to  claim 1 , wherein the metal blank comprises a steel alloy having air hardening properties. 
     
     
         9 . The process according to  claim 1 , wherein the metal blank is heated to about 890° C. in the heating step. 
     
     
         10 . The process according to  claim 1 , wherein the sound wave of the cooling step has a frequency that preferably is lower than 50 Hz, more preferably lower than 20 Hz. 
     
     
         11 . The process according to  claim 1 , wherein the sound wave is provided from a first end of the confined space so as to propagate through the confined space and away at a second end of the confined space, opposite to said first end thereof. 
     
     
         12 . The process according to  claim 1 , wherein components to be cooled in the confined space are conveyed from the heating step at a first end to a second end in a direction generally transversal to the direction of the sound wave and from said second end to said forming step. 
     
     
         13 . A production line for performing the process according to  claim 1 , comprising a heating unit, a cooling unit and a forming unit as well as conveyors to and from said units.