GB842893A - Furnace ladling apparatus - Google Patents

Abstract

842,893. Discharging molten metal. LINDBERG ENGINEERING CO. Nov. 6, 1956. No. 33888/56. Class 51 (2). Apparatus for the discharge of molten metal, e.g. aluminium, from a melting-furnace 11. connected by one or more channels 13 to a pouring chamber 12, comprises a refractory crucible 16 restricted inlet 19 and a restricted outlet 21 connected to a discharge tube 22 leading to a launder 23. The crucible is closed by a cover 17 provided with a polt 18 connected in turn to a source of air or gas under pressure or to an outlet vent. Vertical tubes 24 and 25 are mounted respectively above and below the inlet 19, the tube 24 terminating slightly below the level of molten metal in the furnace 11. An induction coil 14 may also be disposed around the or each channel 13. Discharge of molten metal is controlled by the apparatus shown in Fig. 4, in which 27 and 31 are three-way valves controlled by solenoids 28 and 33 intermittently connected to a power source 38 by a rotary timer 35. A line 26 supplies gas or air under pressure to valve 27 either directly or through a reducing- valve 32, three-way valve 31 and line 29. In operation, solenoid 33 is energized, connecting valve 34 to the reducing valve 32, subjecting crucible 16 to a gas pressure of six ounces per square inch, to depress the metal level to the top of tube 24, Fig. 1. Further rotation of the timer, de-energizes solenoid 33, opening valve 31 to the vent 34, and simultaneously energizes solenoid 28 connecting valve 27 directly to line 26. Crucible 16 is now subject to a pressure of 20 ounces per square inch, sufficient to depress the metal to the level of the outlet 21, discharging a controlled quantity of molten metal through tube 22. The tube 25 prevents escape of gas into the furnace 11. Still further rotation of the timer de-energizes solenoid 28 connecting the crucible 16 to the vent 34 through valves 27 and 31, thus releasing the pressure and allowing the crucible to re-fill with molten metal. Specification 659,366 is referred to.