| 摘要 |
<p>EXPANDING AND BEADING APPARATUS FOR TUBES AND THE LIKE An apparatus is disclosed for expanding and beading the end portion of a steel tube positioned within an opening of a tube sheet for use in boilers, heat exchangers and the like. The apparatus accomplishes the expansion and beading of the tube with relative portability, substantial efficiency, and minimum noise levels. An elongated housing has one end portion adapted to be inserted into the tube with a plurality of rollers mounted for rotation about the periphery. The rollers are tapered slightly and offset at an acute angle with respect to the central axis of the housing. A mandrel having a taper opposite that of the rollers is positioned therebetween such that insertion of the housing into the tube while rotatably inserting the mandrel between the rollers causes the rollers to roll into the tube along a helical path while shifting radially outward to expand the tube and develop generally axial and substantial inward forces. A beading roll is positioned on the housing and loosely retained so as to engage the end of the tube so as to cold work the end of the tube to provide an arcuate bead in sealed relation with the tube sheet. Substantial forces are transmitted to the beading roll via the housing and these forces are sufficient to deform the end of the steel tube by cold working. The beading roll is capable of transferring these cold working forces to the tube primarily by the provision of two substantial support rollers mounted on roller bearings. An offset bearing member is mounted on the housing to engage and roll along the inner surface of the tube so as to offset bending forces produced by the beading roll on the housing. An alternate embodiment utilizes dual opposed beading rolls while eliminating the offset bearing member.</p> |
