Butt welding

About: Butt welding is a research topic. Over the lifetime, 7153 publications have been published within this topic receiving 44467 citations.

Microstructure of stainless steel single-crystal electron beam welds

Abstract: Previously developed techniques by the authors for the microstructural analysis of welds, that included the effects of both the growth crystallography and the weld pool shape, are applied to several cases involving the single-crystal electron beam welding of an Fe-15Ni-15Cr alloy. This evaluation of weld microstructures and associated dendritic growth patterns is based on a three-dimensional (3-D) geometrical analysis. The present study includes examination of the effects observed in overlapping, multipass autogenous welds and butt welds of two single crystals with different orientations, as well as effects due to variations in the welding speed. Weld pool shapes were found to change significantly with increasing welding speed—becoming narrower in cross section but more elongated in the welding direction. Additionally, all electron beam welds showed evidence of a plateau region in the center of the weld pool. The pool shapes, however, were found to be independent of the crystallographic orientation. Therefore, it is possible to extend the pool shape results to crystals welded in any orientation and even to polycrystals. The over-lapping multipass welds showed remarkable reproducibility from pass to pass and duplicated the structural patterns found in single-pass welds. The similarity in dendritic patterns within each pass indicated that the weld pool shapes were identical in all of the passes. The micro-structure of butt welds of two single crystals with different relative orientations showed a remarkable relationship to that associated with each individual crystallographic orientation, and the micro structure was, in effect, simply a composite of two single-pass microstructures. Additional microstructural details were also examined. The tendency toward branching of dendrites was associated with the transition from one dendrite growth orientation to another. It was also found that the nonpenetrating welds exhibited a small protrusion at the bottom of the weld. It is suggested that the modeling of weld pool shapes can be directly evaluated by comparing the predicted dendritic growth patterns based on the modeled shapes with the actual experimentally observed dendritic growth patterns.

Weld bank data structures for welding applications

Abstract: A data structure for weld programs associates configuration data for a welding system with a plurality of weld programs and weld sequence data. The data structure allows the welding system to be configured for a particular part, operator, or stage in a welding process, and to be easily reconfigured when the part, operator, or stage changes, providing improved efficiency and flexibility in operation.

Method for induction butt-welding metal parts, in particular parts of irregular cross-section

Abstract: Method of butt-welding metal parts by induction, in particular parts of irregular cross-section such as rails, consisting in pressing the parts against one another with an initial pressure for the entire period of heating, in heating them by induction by means of an inductor which encloses the parts parallel to their contours about the plane of their interface, firstly for a first period at a lower frequency and then, for a second period following the first, at a frequency two to four times higher than the first frequency, and, at the end of the second period, in applying the parts against one another at a forging pressure which is from two to more than six times higher than the initial pressure. The quality of the welded joint is greatly improved and the dimensions of the bulge or upset are limited by restricting the depth of the penetration of the induced current to both sides of the interface by means of two short-circuited turns disposed symmetrically relatively to the inductor to either side thereof.