Patent GB-1130981-A (GB)
Title: Apparatus for severing metal slabs
IPC: B23D45/18
Filed: 1966-08-19
Abstract: 1,130,981. Sawing. UNITED STATES STEEL CORP. 19 Aug., 1966 [21 Sept., 1965], No. 37328/66. Heading B5L. Apparatus for severing a continuously moving metal slab comprises a longitudinal carriage 21 mounted on a stationary base for movement with the slab and having a frame extending under the line of travel of the slab, means 25 for clamping the carriage to the slab for travel therewith, rollers 24 mounted on the carriage and underlying the path of movement of the slab for supporting the slab during movement thereof with respect to the carriage and when the carriage is clamped to the slab, a lateral carriage 30 mounted on the longitudinal carriage for travel transversely of the slab, and a rotary saw blade 32 mounted on the lateral carriage for severing the slab when the longitudinal carriage is clamped to the slab. The apparatus is located at the output end of a machine 52 for producing a continuously-cast slab which passes through the apparatus into an output conveyer 53 for the cut slabs. The longitudinal carriage 21 is movable along tracks 22, which have aluminium bronze anti-friction bearing surfaces (60, Fig. 3), by means of rack- and-pinion mechanism (63) driven from a motor 61. The lateral carriage has wheels (70, Fig. 2) which run on rails (71) on the carriage 21 and is prevented from lifting off the rails by guide rollers (72) engaging guide surfaces on the rails. The lateral carriage is movable by a motor (73) driving through reduction gearing (74) a rack- and-pinion mechanism (75). A pivot (90, Fig. 2) on the lateral carriage supports a mount (31) for a saw blade (32) which is belt-driven from a motor (80), the mount being movable about the pivot by an hydraulic motor (92) to raise and lower the saw blade between inoperative and operative positions. The longitudinal carriage 21 has a portion which extends below the line of travel of the slab and has a number of rollers 24 for supporting the slab as it travels over the carriage. Other retractable rollers (40, Fig. 2) are disposed below the path of the slab and are raised and lowered in sequence during the movement of the longitudinal carriage to support the slab as it passes through the apparatus. Each roller (40) is mounted on a frame (106, Fig. 6) vertically movable in guide ways (108) in the base of the apparatus by an hydraulic motor (101) carried by a pillow block (102) on a supporting frame (103). The block is adjustable relative to the frame by shims (104) to effect vertical adjustment of the roller. The longitudinal carriage 21 also carries spaced clamps 25 for engaging the slab during the sawing operation. Each clamp has upper and lower clamping assemblies (120, 121, Fig. 8), each lower clamping assembly comprising three hydraulic clamping cylinders (150) having heads (151) guided in a block (153), the heads engaging the lower surface of the slabs. Each upper clamping assembly includes three clamps (123) connected by pins (129) extending with clearance through holes in the clamps to a head (126) vertically movable by screw jacks (125) driven by a motor (125a). A rod (140) is disposed in the upper clamping assembly and when a shoe (123) is displaced relative to the head upon engagement with the slab, the rod is displaced to actuate a switch (96). In operation, the slab to be cut is supplied from the continuous casting machine 51 and is engaged by a horizontal hold-down roller (50, Fig. 4) and edge rollers 51, the slab being supported on the rollers 24 of the carriage 21, the first two of the support rollers (40) being in their retractedposition. When the leading end of the slab is in a position determined by a hot metal detector, the motor 61 is actuated to move the longitudinal carriage 21 and the clamps 25 are engaged with the slab. The engagement of the clamps is sensed by the switch (96) and initiates movement of the lateral carriage to effect the sawing operation. During the movement of the longitudinal carriage, the support rollers 40 are segmentally operated to support the slab and move out of the path of the carriage. At the end of the sawing operation, a limit switch is operated to open the exit clamp 25 and accelerate the rollers 24, which are driven by motors 65, to advance the cut piece of the slab. At the same time, the saw blade is lifted and the lateral carriage retracted. After a time delay, the entrance clamp 25 is opened to enable the longitudinal carriage to be returned to its initial position. The saw blade may be cooled by a water spray.