GB672386A - Improvements in or relating to the centrifugal casting of pipes and the like - Google Patents

Abstract

672,386. Centrifugal casting-machines. CENTRAL FOUNDRY CO. March 9, 1950 [March 18, 1949], No. 5949/50. Class 83 (i). Molten metal is poured into a centrifugal mould from a ladle which is tilted by a pneumatic cylinder at a speed which is automatically controlled, according to the position of the ladle itself, by a hydraulic cylinder having its piston secured to the ladle and having a by-pass valve actuated by linkwork connected to and moving with the ladle. A tiltable ladle 10 and a pouring trough 15 are mounted on a wheeled carriage 22 movable by fluid pressure means to and from the pouring position in which the trough projects into a centrifugal mould 16, Fig. 1. Tracks 24 on which the carriage runs are vertically adjustable. The ladle 10 is clamped to a framework 36 which at its forward end has trunnions 35 mounted in side plates of the carriage 22 and at its rear end has two lateral arms 39 to which are secured the rods of pistons operating in vertical cylinders 11, 43. The cylinder 11 is connected to a source of fluid pressure and serves for raising the rear of the ladle to effect pouring. The cylinder 43 contains liquid and its upper and lower ends are connected by a pipe 46 in which is a valve 13 operable by a slotted arm 47 adjustably secured to an arm 48 which is in turn adjustably secured to an arm 52 which moves with the ladle. The valve 13 is thus operated in accordance with the tilting movement of the ladle and the linkages 47, 48, 52 are preferably so adjusted that the rate of tilting of the ladle decreases as pouring proceeds. In casting a 63 pound pipe 4 inches in diameter with a wall thickness of ¢ inch, half the metal would be poured in the first third of the pouring cycle of 3.6 seconds, one-third of the metal would be poured in the second third of the cycle and the remaining one-sixth of the metal in the last third. In order that the valve 13 should not hinder a rapid return movement of the ladle, a by-pass conduit 53 with a one-way valve 54 is provided. Additional liquid can be supplied to the system by a pipe 55 when required. Specification 626,723 is referred to. '