The Study On Submerged Arc Welding Seam Self-tracking System

With the development of welding automation and intellectualization, the application of welding seam tracking system appears more and more important. Because in the welding production there are kinds of influence factor, for example the mismachining tolerance and thermal distortion and inaccuracy chucking appliance, welding seam real-time automatic tracking takes seriously topic in domestic and foreign now. In this paper, there are CCD camera as a seam tracking sensors, designed to PLC (Programmable Logic Controller) as the core of the tracking system, focusing on researching for SAW indicator in the several forms, given the position of everyone indicator and the principle of the indication effect and In-depth studying the different situations of image processing algorithms.In this paper, the principle of the seam tracking system is: capturing Submerged Arc Flux collection in the area of coverage and the front seam indicator image by CCD, the image signals through coaxial cable reach image acquisition broad. Image acquisition board for some hardware in the preconditioning (such as quantification); then by software-driven interface, we can make further image processing, image analysis by PC so as to find the welding seam, PC communication through free and then the welding seam information puts into the PLC (Siemens PLC). IPC further analyzes the images and extracts the position of the welding seam, and then gives the real-time welding information to the PLC by the free communication. S7-214 as the core of PLC controlling system controlls two stepper motors to band the blowtorch moving, eliminates the deviation of the blowtorch and welding seam, makes up a closed-loop control system wholly in order to achive the goal about the submerged-arc welding seam tracking.By the intensity of adjuvant lamp and adding filter in the front of camera, analyze the rule of image change, confirms an ideal state finally. The non-linear filtering method is adopted in order to reduce noise in image processing technology; The new Oust of algorithm has been chosen in Image segmentation; The identifying binary images using a new strategy: Edge is emptied from the internal target; Welding seam center extraction use Line-by-line scanning method and Projection method. Above mentioned each algorithm's principle and realizing the process, this paper has carried on the detailed introduction. Through the different image processing algorithm effect's experiment and the comparison, the paper obtains an image processing method that is quite reasonable and actual. This is: has designed the control software system about gathering, the processing image and the transmission data by using the VB programming, and finally realizes the good seam tracking on weldment bevel without the striking the arc situation.