Process monitor for open die forging

Abstract

A method for monitoring and controlling open die forging processes, includes: a) calculating the geometry evolution of a workpiece during open die forging using empirical models; b) in parallel with step a), that is to say at the same time or at least partially overlapping times as step a), calculating the workpiece temperature across the cross-section of the forged workpiece; c) calculating the distribution of the change in shape over the length of the workpiece, preferably by using the geometry evolution calculated in step a); and d) manually or automatically controlling the distribution of the change in shape in a predefined region on the basis of the distribution of the change in shape calculated in step c).

1 .- 15 . (canceled) 
     
     
         16 . A method for monitoring and controlling an open die forging process, comprising:
 a) calculating a geometry evolution of a workpiece during open die forging using empirical models;   b) at a same time or at least partially overlapping in time with step a) calculating a workpiece temperature across a cross-section of the workpiece;   c) calculating a distribution of a change in shape over a length of the workpiece; and   d) manually or automatically controlling the distribution of the change in shape in a predefined region based on the distribution of the change in shape calculated in step c).   
     
     
         17 . The method as in  claim 16 , wherein calculating the distribution of the change in shape over the length of the workpiece is performed by using the geometry evolution calculated in step a). 
     
     
         18 . The method according to  claim 16 , wherein step a) further comprises defining a start line and an end line for the open die forging process. 
     
     
         19 . The method according to  claim 18 , wherein step a) further comprises correcting the geometry evolution. 
     
     
         20 . The method according to  claim 16 , wherein step b) further comprises measuring a workpiece temperature by a pyrometer or a thermographic system. 
     
     
         21 . The method according to  claim 20 , wherein step b) further comprises regulating the open die forging process for maintaining a predefined workpiece temperature range. 
     
     
         22 . The method according to  claim 20 , further comprising
 using the measured workpiece temperature as a comparative variable in a calculation model,   wherein the calculation model calculates the temperature distribution over an entire cross-section of the workpiece and over a length of the workpiece.   
     
     
         23 . The method according to  claim 20 , further comprising
 monitoring a material-dependent maintaining of a predefined workpiece temperature range.   
     
     
         24 . The method according to  claim 20 ,
 wherein the method does not use any measurement data other than measurement of the workpiece temperature and measurement signals of an open die forging press and/or a workpiece manipulator selected from the group consisting of a press stroke, a press force, and a manipulator position.   
     
     
         25 . The method according to  claim 16 , wherein steps a) to c) are calculated online during the open die forging process. 
     
     
         26 . The method according to  claim 16 , wherein the workpiece is a round block, a stepped shaft, a conical cast block, and/or has partially forged-over regions. 
     
     
         27 . The method according to  claim 16 ,
 wherein calculating the geometry evolution comprises calculating a stretching and spreading behavior of the workpiece in a material-dependent manner.   
     
     
         28 . The method according to  claim 16 ,
 wherein variables calculated in step a) for the geometry evolution are used as input variables for a change of shape model, and   wherein the distribution of the change in shape and, in case of an inhomogeneous distribution of the change in shape over the cross-section and/or the length of the workpiece, a core compaction are ascertained.   
     
     
         29 . The method according to  claim 16 , further comprising
 providing a control and regulation unit,   wherein the control and regulation unit is connected to a database, and   wherein all recorded measurement data and calculated parameters are stored in the database.   
     
     
         30 . The method according to  claim 29 , wherein the control and regulation unit
 displays the calculated variables of geometry distribution and/or distribution of the change in shape and/or temperature distribution to an operator,   issues warnings in the event of deviations from a target state, due to a region having too low a change of shape, and/or   issues suggestions for regulating the open die forging process for maintaining the predefined ranges and/or achieving an ideal distribution of the change in shape.   
     
     
         31 . An open die forging press,
 wherein the open die forging press is connected to a control and regulation unit, and   wherein the control and regulation unit is configured to perform the method according to  claim 16 .   
     
     
         32 . The open die forging press according to  claim 31 ,
 wherein the control and regulation unit is connected to a database in which all measurement data recorded by sensors and parameters calculated by a change of shape model can be stored.   
     
     
         33 . The open die forging press according to  claim 31 ,
 wherein the control and regulation unit is connected to a display unit, by which the calculated variables of geometry distribution and/or distribution of change in shape and/or temperature distribution can be displayed to an operator.