GB782636A - Tube drawing apparatus - Google Patents

Abstract

782,636. Drawing tubes. ROBERTSHAW-FULTON CONTROLS CO. Jan. 24, 1956 [May 19, 1955], No. 2312/56. Class 83 (4). In apparatus for drawing a tube 200, Fig. 5, through a stationary die 84 a mandrel 68 is reciprocated within the die while the tube is drawn through the die by mechanism such as a draw carriage 126, Fig. 1, which exerts a continuous pull. The mandrel 68 is pivoted on a carriage 16 which is reciprocated over a slideway 14 by means of a double-acting hydraulic piston 36 under the control of solenoid switches 25, 27 actuated from a roller 24 moving with the carriage 16. The mandrel may include means for lubricating the interior surface of the tube. The end of the tube 200 has lips 202 which engage over a head 192 initially fitting in a conical recess 190 in the end of the mandrel 68 and having a head portion 154 which is engaged by gripping jaws 132 on the drawing carriage 126. Movement of the carriage 126 on wheels 130 over guide tube 133 is provided by a pair of hydraulic cylinders 94 mounted between fixed members 82, 92 of the machine frame 10 and actuating piston 100 (not shown) attached to a draw plate 104 on the carriage 126. The gripping jaws 132 are mounted on the draw plate 104 and comprise radially slidable jaw pieces 150, Fig. 6, actuated by pivoted levers 146 engaging in the jaws and held in the clamping position by an axially slidable chuck head 144. For opening the jaws the chuck head 144 is retracted by a piston rod 166 of an hydraulic cylinder 168 and attached by a pin 160 movable in a slot 162. Hydraulic lines 180 to the cylinder 168 from a solenoid valve 188 are coupled through a hose reel 182. The length of tube drawn is limited by an adjustable stop 214 on a push rod 208 which is engaged by a stop 212 on the carriage 126 to move the push rod 208 against the action of a spring 210 and actuates a switch 204. The mandrel 68 is mounted on a bell crank 64 which can be tilted to raise the mandrel for insertion or removal of tubes. A wheel 66 on the end of the bell crank arm 64 runs over a table 70 which is elevated as required by an hydraulic cylinder 74. The apparatus may be sequentially operated automatically under the control of a series of solenoid-operated hydraulic valves or the separate operations may be manually controlled. Reference has been directed by the Comptroller to Specification 244,447, [Class 20 (ii)].