Abstract: By pressing a wiping member 37 of a wiper 33 onto a concave curved surface 28 and an upper side flange portion 30 of a squeeze roll 8, spatter is wiped off by the rotation of the squeeze roll. In the wiper 33, the wiping member 37 is fixed to a base plate 36 that is linked via a rotatable arm 35 to a shaft body 34. The wiping member 37 is formed from flannel and an anchor member 39 is provided on the base plate 36 on which the wiping member 37 is fixed. The anchor members 39 of a pair of squeeze rolls are linked under tension by a coil spring 40 so as to press the wiping members 37 against the concave curved surfaces 28. A cooling tube 42 for discharging cooling water is provided to the rear of the squeeze roll in the rotation direction of the squeeze roll.

Abstract: A concave curved surface 28 having an arc configuration with the radius R as seen in a vertical cross sectional view is formed over an entire side surface of each of squeeze rolls 8. Below the concave curved surface 28 is provided a lower side flange portion 29; while above the concave curved surface 28 is provided an upper side flange portion 30. A virtual line that includes the center point of the radius R is provided parallel to a rotation shaft 22 of the squeeze roll 8 and facing the concave curved surface 28. With the distance from the virtual line to the lower side flange portion 29 taken as “a” and the distance to the upper side flange portion taken as “b”, the relationship a<b is established.

Abstract: A rotation shaft 34 of each squeeze roll 8 is rotatably supported by bearings 36a, 36b inside a through hole 35 formed in bearing boxes 23a, 23b. Tapered rolls 37 are provided in the bearings that support the rotation shaft 34. Side surfaces 28a, 29a of both wing portions of the bearing boxes are formed in a tapered configuration and these two side surfaces are fixed by being pressed by side plates 24a, 24b. A spacer 32 is provided between an upper wide diameter portion 34a and each squeeze roll 8 for adjusting the height of the pair of squeeze rolls. By tightening double nuts relative to the bearing boxes, the rotation shaft of each squeeze roll can be adjusted to counter wear in the tapered surfaces of the rotation shaft or in the tapered rolls 37.

Abstract: This apparatus manufactures a welded tube by curling a metal strip T into a tube shape, heating the two edges thereof using an induction heating coil 6, and pressure welding the two edges using squeeze rolls 8. A ferrite core 21 for increasing heating efficiency that has a substantially circular arc shaped cross section is provided at a position on the top surface portion 25 of an impeder body 24 directly below the induction heating coil 6. A protective layer 29 formed from fluororesin is provided on the top surface of the impeder body and this protective layer catches spatter “c” generated during welding. The distal end of a cooling water supply tube 27 is embedded in a concave groove 26 in the impeder body 24 and the ferrite core 21 is cooled via a through passage 21a formed between the ferrite core 21 and a flat surface portion.

Abstract: In the bead cutting apparatus of the present invention a cutting tool 22 is provided on the distal end of an impeder 21 so as to be able to swing. This swing uses a first bolt 45a as a fulcrum and is within a range allowed by the difference between the external diameter of a second bolt 45b and the internal diameter of a second hole 47. A blade tip portion 33 is provided at the distal end of a cutting tool body 32 and is provided at the impeder 21 side such that a cutting blade 34 can make contact with an internal surface bead B of a tube P. A spring member 38 is fixed by a fixing member 39 to a position partway along the cutting tool body 32 on the opposite side thereof to the cutting blade 34.

Abstract: The object of the present invention is to offer a heat transfer tube having a grooved inner surface, wherein the side edges of the board material do not form a waved shape and cracks do not form during tube expansion. In order to achieve this object, the grooved-inner-surface heat transfer tube of the present invention has a metallic tube with an inner circumferential surface, on which are formed a weld portion which extends in an axial direction of this metallic tube, a pair of projecting strip portions formed parallel to and separate from this weld portion, and a plurality of fins formed in an area between these projecting strip portions. The fins are formed with a constant angle with respect to the tube axis, and the ends of these fins are connected with the projecting strip portions. The thickness of the metallic tube within the grooves formed between the fins is made to increase in approaching the weld portion within an area surrounding the weld portion wherein the central angle is within 30.degree..