Many bars and tubes produced for precision applications are not totally straight, despite advanced manufacturing processes. This can create vibration during machining and grinding operations required to finish the tubes and bars, potentially damaging tooling and creating quality issues. Coldwater Machine has developed a tube and bar straightening system to address this situation.
Bundles of bars/tubes are loaded onto an accumulation deck and then automatically fed to the straightening equipment. In the straightening process, the tube or bar is rotated to measure the runout with sensors at multiple data points along its length. This data is sent to the PLC where it is compared to the straightness specification to determine where it needs to be corrected.
The PLC determines the initial point needing correction and the servo press is indexed along the bar by a servo rail to the indicated location where it then bends the bar/tube to specification. The piece is then rotated again to collect the data points and determine if there are other points that need attention. This process continues until all the data points are found to be within specification. From there, the bars may be moved out of the machine, automatically or by an operator, to the next process.