Patent GB-215146-A (GB)
Title: Improved method of welding plated structures and means for positioning the components of said structures before and during welding
IPC: B25H1/00
Filed: 1923-03-08
Abstract: 215,146. Roberts, R. March 8, 1923. Uniting by fusion.-The parts of plated structures such as shells, decks, tanks, bulkheads. superstructure of ships, the shells, decks and bulkheads of pontoons, and circular or prismatic tanks, are held with the parts to be fusion welded in contact, by a series of adjustable pressure devices such as screws, hydraulic or pneumatic rams &c., which bear on mechanically anchored frames, beams, carriages, pillars, &c. which do not penetrate the parts through the seams and allow sufficient elasticity to permit the parts to adjust themselves to temperature changes. Welding is effected from the centre or one end of each plate outwards in lateral and longitudinal directions so as to cause the heat to flow towards the extremities and so neutralize internal heat stresses. In welding horizontal plates 50 to girders 51, Figs. 1 and 4, a pair of frames 52 at opposite sides of the plate, having projections 53 which are clamped by screws 54 to the girders, and having between the girders sectional inner flanges 55 which support sectional butt straps 61 previously welded to the plate, are slotted at 57 to receive beams 56 provided with a series of vertically adjustable screws 58 to close the plates on to the girders. Screws 59 abutting against brackets 60 on the frames engage the butt straps to straighten the plate and bring the butt straps into alignment with the girders. If butt straps are not used the plate is supported on liner plates temporarily attached to the flanges. In a modification for heavy horizontal plates, the frames carrying the beams 56, Fig. 5, consist of a wheeled carriage travelling in channel guides 63 which carry the projections 53. The carriage is fixed in position by hooks 69 on bolts 68. Clamps 64 act on the edges of the plates and if the girders are joggled or plate bolted to the channel guide projects under the plates 50. Countersunk pins may project through the web of the channel to retain the girders in position after adjustment by the screws 54. An apparatus for clamping a horizontal filling strake of plates 71, Figs. 8 and' 9 to the edges of the blank strakes 50 and to the girders 51, consists of stands 73 secured by bolts 72 passing through holes in the plates 71 and girders 51 at each end and by pins 74, which are welded to the plates 50 and after welding of the joints &c. are cut off flush and welded permanently thereinto. The stands support beams 56 carrying the screws 58 to clamp the plates to the girders and also longitudinal beams 75 carrying screws to clamp the edges of the plates and butt strips against screws 58 or bars 79 adjusted thereby which rest on girders 78 secured by brackets 77 to the girders 51. The ends of the plates and the butt strap are clamped between screws on a beam 56 and screws or a bar 82 adjusted thereby supported on transverse girders 80 carried by girders 78. Vertical plates to be welded to vertical frames are first secured bv bolts at each side to the frames and then clamped by horizontal pressure screws carried by beams which have runners movable along a Z-bar secured to the frames and are temporarily anchored to the frames. In welding vertical filling strakes of plates 93, Fig. 18, to frames and adjoining strakes, the parts together with stands 95 are secured by bolts 94, 96. The upper stands support a channel guide 97 in which may travel a carriage 99 having depending arms with rollers running on the plate and also having hinged beams 102 for the pressure screws 87. The beams mav be secured to the stands by slidable box members 103 which support longitudinal beams for the screws which clamp adjoining plates together. In welding the bottom plates of a ship to the frames, the plates are brought under the frames on a wheeled carriage and are lifted therefrom and clamped against the frames by screws carried by a series of adjustable transverse beams mounted on the carriage. Screws supported by beams attached to the upper faces of the frame serve to press the joints together. When welding large areas of deck plating wheeled carriages 114, 122, Fig. 23 running on the edges of the plates and operated by motors or by hand or power-operated winches 120 are used. The carriages 114 may be fixed by attachments 118 to bolts or pins 119 welded to the plating 116. The plate is clamped by screws carried by beams 56 and by screws abutting against the underside of the side frames of the carriage. The lower carriage 122 has two pairs of transversely adjustable screwjacks 126 supporting girders 128 on which are hinged screws carrying bars 79. Adjustable transverse beams with upwardly acting screws may be supported between the girders. A number of screws provided with bars 79 linked together at 129 may be pivoted to the bottom of the carriage so that by slightly releasing the screws they may be simultaneously removed from the plate by operation of a lever 130. The carriage also has beams 56 for supporting downwardly-acting screws. The lower girders 132 may also carry girders 78 supporting screwadjusted bars 79. The lower carriage provides staging when welding the plate 116. The carriages may, by their weight, serve as pressure appliances, and the closing and welding operations may be simultaneously and progressively effected. In welding plates on small vessels or structures, the vertical plates 133, Fig. 28 are supported by bolts 139 and clamping effected by screws 58, some of which rest against and others are carried by beams 141 on a number of vertically adjustable pillars 137 on a wheeled carriage 135. Stays 138 fit between the pillars and the structure and hinged connections 140 are used' at the top. Internal screws 142 are supported from girders 134 as described with reference to Figs. 8 and 9. Similarly mounted screws 152 clamp the bottom plates at the joints against bars 150 mounted on screw-jacks 149 carried by a wheeled carriage 147. The carriage 135 has a platform 143, 144 with protecting rails 146 the platform 144 being vertically adjustable and supported by tubular stanchions 145. In welding the circular platiug of a tank, the bottom plates 154, Fig. 34, are first welded or clamped in position, plates 156 of the first strake then welded together and to the curved' sectional foundation angle 155 and then to the bottom plate. Plates of succeeding strakes are provided with welded T-lugs 164 and then lifted into position so that the lugs slide over the plates of the proceeding strake. A curved bar 168 is attached by clamps to the top of the plate prior to lifting. The T-lugs are cut off and the bar 168 removed after welding. The plates are clamped at the joints by screws 58 projecting from beams 162 carried by two sets of movable pillars 157 connected together by bars 158. Stays 165 engaging with beams are attached to the lugs 164. Adjustable stagings 160 are mounted on brackets on the pillars. Extensions 166 are provided for the pillars for welding succeeding strakes.