Abstract:
Molten metal (6) in a furnace (5) and containing particles of solid material (not shown) in suspension is cast in moulds (1) conveyed continuously past the mould-filling station shown by a conveyor (4). To maintain the particles in suspension and keep the metal (6) homogeneous throughout the furnace (5), a paddle-wheel rotor (10) driven by a motor (13) keeps the molten metal in constant movement. A curved guide vane (14) is shaped, placed and oriented so as to divert some of the centrifugal flow from the rotor (10) towards the delivery tube (8) for the moulds (1), thus ensuring that the tube (8) is supplied with freshly-agitated metal.
Abstract:
In a filling-tube construction (1, 2) for providing a connection between a mould (6) to be filled with molten metal and a mould-filling furnace (3) containing molten metal (5), said mould (6) having at least one casting cavity (7), the lowermost part of each such cavity communicating with a filling duct (8), at least one end of which is open to the outside of said mould (6) and adapted to be temporarily connected to the filling-tube construction (1, 2) to receive molten metal (5) from the mould-filling furnace (3), the mould-filling furnace being adapted to contain molten metal (5) and to transfer said molten metal (5) under a controlled pressure through the filling-tube construction (1, 2) and to the filling duct (8), the filling-tube construction comprises a first section (1) extending from a position close to the bottom of said mould-filling furnace (3) up to an intermediate position closer to the filling duct (8) and at least one separate second section (2) providing a connection from the upper end of the first section (1) to the open end of the filling duct (8) and adapted to provide a fluid-tight connection to the upper end of the first section (1) and the open end of the filling duct (8). In this way an easy adjustment and/or exchange of parts of the filling-tube constructions can be provided by simply adjusting and/or exchanging the second section (2), without disassembly of the connection between the first section (1) and the mould-filling furnace (3). The invention also includes a method of modifying a conventional constructed filling tube to a filling tube as described above.
Abstract:
When pouring casting cavities in casting moulds having after-feeding reservoirs, tubular lances are introduced, firstly with their point at a short distance from the after-feeding reservoir, after which the lances are pressurized from a pressure chamber and by means of a member with an inclined surface pressed downwardly through the last short distance to the after-feeding reservoir so as to pressurize the latter. With this arrangement it is possible to pressurize the after-feeding reservoirs without the need of equipping the casting moulds with complicated extra equipment and without risk of the molten metal being pressurized unnecessarily.
Abstract:
When casting metal articles in a mould by forcing molten metal upwardly through a filling tube by gas pressure in a closed chamber, the datum level just below that of a connector connecting the filling tube to the mould is registered by a level sensor in a sensing tube while the latter's upper end is connected to atmosphere through a vent tube. At the same moment, the pressure is measured by a pressure sensor and recorded by a control unit and maintained constant by the latter after the emptying of the sensing tube, by connecting its upper end to the chamber through an equalizing tube, until the pressure is increased to fill the mould according to a predetermined function of time programmed into the control unit. The starting point for the filling of all moulds in succession is the same, regardless of the amount of metal in the supply unit.
Abstract:
A method of ascending casting in a casting cavity where filling from the bottom results in a region of reduced pressure formed during the cooling in which solidification can be expected to take place last. The region is post-fed with molten material from a shortest possible feeding duct. By doing this, the consumption of casting metal is reduced, because it is no longer necessary to use a surplus of molten material to keep the bottom ingate open for feeding purposes and the consumption of mold material is also reduced because it is no longer necessary to adapt the mold to accommodate surplus molten material.
Abstract:
In an arrangement of an ingate system with feeding reservoir for feeding castings, preferably in moulds with pouring form the bottom (ascending casting), with which ingate system at least a feeding reservoir is connected. The ingate system is connected to one or a number of mould cavities least one feeding reservoir (7) is provided consituting a widened part of a duct (4) or a part of a duct in the ingate system (1), and that a partition (6) consisting of a gauze screen (6) or equivalent is provided separating the feeding reservoir (7) and the duct (4).
Abstract:
The present invention relates to a method for casting ferrous or heavy metal articles in vertically parted sand moulds of a mould string plant through an inlet below or aside the mould cavity, by filling the moulds with molten metal by counter-gravity delivery using a source of pressure. The pressure is varied during the filling procedure to steer the flow speed and impact on the mould of the molten metal upon complete filling of the mould cavity is reduced.
Abstract:
In casting metal objects in casting cavities (2) in moulds (1), connectable to a pressurized mould-filling furnace (5) through a delivery tube (8) and a connector (9), an external riser (13) is connected to and extends upwardly from the junction of the tube (8) and the connector (9). The riser (13) is used as a temporary reservoir in which the level of molten metal is regulated by controlling the gas pressure in space 7 in the furnace (5) such that the filling head, defined as the difference in level between the metal in the casting cavities (2) and that in the external riser (13), is kept constant or made to vary in a desired manner, e.g. so as to cause the level in the cavities to ascend at a substantially constant rate. The invention makes it inter alia possible to produce high-quality aluminum castings in sand moulds, e.g. using automatic foundry equipment of the DISAMATIC® type.