Simulation of Welding Distortions in Theory and Practice

Martin Birk-Sørensen, Henning Kierkegaard

    Research output: Chapter in Book/Report/Conference proceedingBook chapterResearchpeer-review

    Abstract

    In the last few years the use of robot welding processes has increased significatnly. The programming of the robots has until now mainly focused on high efficiency, i.e.high torch rate time, and hence, minimising the inefficient "travelling" time. Together with developing high-performance welding equipments,procedures should also be made for controlling and/or reducing the necessity of corrections owing to thermal deformation, such as straightening and adjustment work. The expenses of reworking remain an important part of the production cost. These inaccuracies partly arise from thermal deformation due to cutting and welding and parlty in the form of dimensional variation due to human factors. Measurements have been made of the production line for assemblies. The measurements show that distortions related to the multirobot welding are a factor which can rather easily be controlled by an optimised welding order. Welding test samples prove that the constraint of the sample and the time between each pass in a multipass weld affect the magnitude of distortion. Experiments with welding specimens in the form of butt-and fillet welds have been carried out. They show angular deflections as well. A finite element program has been used to simulate a one-sided fillet weld. The simulation agrees reasonably with the measurements. The analysis is divided into two tasks: temperature distribution and non-linear elalstic-plastic behaviour of the material. The temperature distribution is found by use of Rosenthal's analytical solution for a 2D finite plate. The temperature profile is used in an FE-model, which solves the mechanical problem. Finally, a simple analytical expression has been set up to calculate the bending of a rectangular plate by an asymmetric temperature profile.
    Original languageEnglish
    Title of host publicationICCAS'97. 9th International Conference on Computer Applications in Shipbuilding
    Place of PublicationYokohama
    PublisherThe Society of Naval Architects of Japan
    Publication date1997
    Publication statusPublished - 1997
    Event9th International Conference on Computer Applications in Shipbuilding - Yokohama
    Duration: 1 Jan 1997 → …

    Conference

    Conference9th International Conference on Computer Applications in Shipbuilding
    CityYokohama
    Period01/01/1997 → …

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