Patent GB-759119-A (GB)
Title: Improvements in or relating to nipple forming means
IPC: B21C37/29
Filed: 1954-10-20
Abstract: 759,119. Flanging. BABCOCK & WILCOX, Ltd. Oct. 20, 1954 [Oct. 21, 1953], No. 30188/54. Classes 83 (2) and 83 (4). Making pipe fittings.-A device for forming an external annular projection or nipple on a thickwalled steel tube by pressing a mandrel outwardly through a hole in the tube wall while the metal around the hole is hot by means of a wedge-shaped member moving longitudinally within the tube, is characterised in that the mandrel is arranged to slide in a bearing formed transversely of a liner attached to the end of the cylinder of an hydraulic press arranged to extend within the tube, the wedge member being connected to the ram of the press and arranged to slide longitudinally of the liner to force the mandrel outwardly into the hole in the tube wall. The device includes a cylinder 1 and a ram 2 provided at one end with a collar 3 and a cylindrical portion 4 surrounded by a packing ring 6. At the other end the ram passes through a stuffing-box 8 and is attached to a wedge member 12. Outwardly of the stuffing- box a U-shaped liner 14 is secured to the cylinder 1 by a bayonet joint 15. The liner guides the wedge 12 and has longitudinal channels 19 for receiving the ram. Two pairs of diametral channels 20 and 21 in the liner guide mandrels 22 and 23 respectively having chamfered ends corresponding to the wedge angle. The end of the cylinder 1 remote from the stuffing-box is closed by a plug 25 having a central bore 26. An extension of the plug passes through a bore in a connecting piece 28 and is formed with a seat for a fluid pressure pipe 29. A second fluid pressure pipe 31 is attached to the connecting piece 28. A passage 32 in the connecting piece connects the pipe 31 with a bore 33 in the cylinder wall which communicates with the interior of the cylinder. A resilient tube 35 ensures a fluid. tight joint between the passage 32 and the bore 33. An extension sleeve 37, the same external diameter as the cylinder, is attached to the connecting piece 28. A locating ring 38 is slidable upon the cylinder 1, the connecting piece 28 and the sleeve 37. A U-shaped distance piece 41, the thickness of which equals the distance between the centre lines of the channels 20 and 21, fits over the sleeve 37. In operation, to form a nipple on the tube 43, a hole 47 is drilled in the tube wall and the flanging device is inserted in the tube with the wedge in the retracted position until the mandrel 23 is coaxial with the hole 47. The distance piece is placed over the extension tube 37 so that it abuts the end of the tube 43 and the locating ring is positioned against the distance piece and locked in position by a projection 42 on the distance piece which enters a slot 40 in the locating ring. The device is withdrawn and the tube heated around the hole 47 and the device re-inserted. Fluid pressure is admitted to the cylinder to operate the wedge which moves the mandrel 23 radially outwardly to partially form the nipple. The wedge is retracted, the device again withdrawn and the mandrel 23 and the distance piece 41 removed. The device is again inserted in the tube until the locating ring abuts the end thereof and the mandrel 22, now in alignment with the partially flanged hole, is operated to complet the nipple. For forming nipples on tubes of large internal diameter the liner 14 is supported on an adaptor 45 secured thereto (Fig. 4).