Conventional tubular joints for offshore structures show a typical weakness in the brace to chord intersection, affected by the presence of single side manual weld joints. The pressed/extruded node concept is based on an approach whereby the conventional weldings of the brace to the chord is replaced by a brace stub which is pressed out from the chord plate segment. This represents an innovative fabrication approach which provides the industry with tubular nodes with greatly improved fatigue performance. This paper describes the manufacture of several nodes ranging from small scale to the max. dimensions (chord dia. 240, 500, 3600 mm). Fatigue, static strength and mechanical test results are also reported. Tubular nodes for jack-up rigs cannot be extruded, since extrusions may hinder the jacking-up operations. The problem has been reverted by a special re-design whereby shear forces only are transferred to the weld, thus avoiding local bending stresses. This paper describes the manufacture of small scale prototypes.


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    Title :

    Manufacture of offshore tubular nodes by press forging


    Additional title:

    Herstellung von Offshore-Plattform-Rohrknotenpunkten durch Preßschmieden


    Contributors:


    Publication date :

    1989


    Size :

    6 Seiten, 20 Bilder, 4 Quellen


    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




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