DEVICE FOR CENTERING, PRESSING TO FORM THE INNER SHAPE OF, STRAIGHTENING AND CLAMPING BUTT JOINTS OF ROTATIONALLY SYMMETRICAL HOLLOW MEMBERS DURING A JOINING PROCESS USING FRICTION STIR WELDING OR FUSION WELDING

摘要

The device comprises a clamping body (10) that includes a drive unit, is adjusted to an internal diameter of the hollow articles and is placed centrally in relation to an axis of the hollow articles. The clamping body is designed as a weld pool holding element in the form of a centering, inner-shape-forming, straightening and clamping disk, which is subdivided into circular-segment-shaped primary and secondary jaws, on each of which hammer-shaped forked retention elements are radially mounted in the direction of the axis of the hollow articles. The device comprises a clamping body (10) that includes a drive unit, is adjusted to an internal diameter of the hollow articles and is placed centrally in relation to an axis of the hollow articles. The clamping body is designed as a weld pool holding element in the form of a centering, inner-shape-forming, straightening and clamping disk, which is subdivided into circular-segment-shaped primary and secondary jaws, on each of which hammer-shaped forked retention elements are radially mounted in the direction of the axis of the hollow articles. Each retaining element is guided in a recess of a support element and is connected in a radially pivotable manner, similar to a toggle lever, to a tappet of the drive unit by a primary or secondary lever. The device further comprises: a primary jaw body made from three primary jaws that are radially held at a hammer-shaped retaining element arranged at the periphery of the disk and extending from the center of the disk with the formation of gaps, where one end of the primary lever is pivotally mounted at the retaining element; a secondary jaw body made of three secondary jaws that are radially held at a support and extending towards the center of the disk, where one end of the secondary lever is pivotally mounted at the support; a carrier element (36) having radially arranged recesses for receiving and shifting the retaining elements; a plunger (20) vertically displaceable in a direction of the center of the disk, where side ends of the primary and secondary levers are held at the plunger for the primary and secondary jaws; and a drive (21) for the plunger for generating centering, pressing, straightening, clamping and unclamping of the primary and secondary jaws radially against the inner surfaces of the hollow body for generating a matching and roundness straightness in the joint area of the hollow body. The secondary jaws are arranged to each other and displaced along the circumference so that a gap is concluded between two primary jaws. The clamping disk engages with an inner side of the joint region of the hollow body, where 65-70% of the joint area corresponding to the inner periphery of the hollow body is subjected for centering by through holes of the primary jaws in a first clamping condition and the necessary centering forces act on the entire inner circumference of the joint area by the radial extension of the secondary jaws into the gaps between the primary jaws using toggle-type power assist in a second clamping condition so that an end portion of the centering, pressing, straightening and clamping disk forms a closed surface for the inner radial mold press of a geometry and shape that matches the joint area. An independent claim is included for a method for centering, pressing, straightening and clamping rotationally symmetrical hollow articles on a flange-pipe-flange or pipe-pipe arrangement.