| 摘要 |
When machining a lengthwise running weld 24 in a pipe, 10 inches, which is formed by bringing together and welding the lengthwise edges of a bandlike workpiece, the pipe weld is subjected in stages and under local deformation of the cross section of the pipe to a rolling between a rolling tool 19 which can be placed against the weld from the outside of the pipe and an elongated mandrel 20, introduced into the pipe, which during the welding bears against a portion of the pipe wall opposite the weld from a retaining element 18 co-operating with the outside of the pipe, wherein the rolling of the weld occurs under a relative motion in the lengthwise direction of the pipe between the pipe with the mandrel secured therein by the roll pressure, on the one hand, and the rolling tool, on the other. In order for the mandrel to be able to have a shorter length than the pipe when using this welding processing technique, after accomplishment of each rolling stage and for a period of time when the roll pressure is made to cease it is necessary to move it in its lengthwise direction to a new working position in the pipe. Thus far, this has been done by pulling the mandrel inside the pipe, which has caused inconveniences that are eliminated according to the invention in that the end portions of the mandrel are provided with running rollers 26 allowing the mandrel to move under rolling contact with the inside of the pipe. <IMAGE> |
