A low-pressure casting apparatus includes a core that together with a mold forms a cavity and a reduced-pressure dryer configured to dry the core under reduced pressure. The core is disposed in the mold, the molded is closed, the core is dried under reduced pressure, and thereafter the cavity is filled with molten metal.

A system (5) and method (800) for unit cell casting of titanium or titanium-alloys is disclosed herein. The system (5) comprises an external chamber (45), a crucible (10) positioned within the external chamber (45), an induction coil (15) positioned around the crucible, an internal chamber (40) positioned within the external chamber (45), and a mold (30) positioned within the internal chamber (40). The external chamber (45) is evacuated and a pressurized gas is injected into the evacuated external chamber (45) to create a pressurized external chamber (45). An ingot (20) is melted within the crucible utilizing induction heating generated by the induction coil (15). The internal chamber (40) is evacuated to create an evacuated internal chamber (40). The titanium alloy material of the ingot (20) is completely transferred into the mold (30) from the crucible (10) using a pressure differential created between the external chamber (45) and the internal chamber (40).

A system (5) and method (800) for unit cell casting of titanium or titanium-alloys is disclosed herein. The system (5) comprises an external chamber (45), a crucible (10) positioned within the external chamber (45), an induction coil (15) positioned around the crucible, an internal chamber (40) positioned within the external chamber (45), and a mold (30) positioned within the internal chamber (40). The external chamber (45) is evacuated and a pressurized gas is injected into the evacuated external chamber (45) to create a pressurized external chamber (45). An ingot (20) is melted within the crucible utilizing induction heating generated by the induction coil (15). The internal chamber (40) is evacuated to create an evacuated internal chamber (40). The titanium alloy material of the ingot (20) is completely transferred into the mold (30) from the crucible (10) using a pressure differential created between the external chamber (45) and the internal chamber (40).

A die-casting machine has a casting mould, a casting chamber, a casting piston arranged in an axially movable manner in the casting chamber, a melt inlet channel which leads into the casting chamber, a shut-off valve in the melt inlet channel, a melt outlet channel which leads from the casting chamber to the casting mould, and a control unit for controlling the casting piston. The control unit and the shut-off valve are configured, after completing a filling phase in a subsequent refilling phase firstly to bring the shut-off valve into an open position and to control the casting piston to move back into the casting start position, in order to supply the casting chamber with melt material via the melt inlet channel, and to control the shut-off valve into its closed position again before the casting piston has reached its casting start position by virtue of its return movement, and to control the casting piston to back-suction melt material in the melt outlet channel by virtue of the further return movement of the casting piston.

A casting mold is provided with a cavity portion and an overflow portion, and the overflow portion is connected to a gas flow path (suction path). A valve (an on-off valve, a shut-off valve) is provided between the gas flow path and the overflow portion. A heating method for a casting mold includes a step of setting the pressure in the cavity portion to a second pressure by sucking gas in the overflow portion and in the cavity portion while the valve is kept open for a second time period shorter than a first time period during casting. The heating method further includes a step of heating the casting mold by supplying molten metal into the cavity portion set at the second pressure, and solidifying the molten metal.

A casting mold is provided with a cavity portion and an overflow portion, and the overflow portion is connected to a gas flow path (suction path). A valve (an on-off valve, a shut-off valve) is provided between the gas flow path and the overflow portion. A heating method for a casting mold includes a step of setting the pressure in the cavity portion to a second pressure by sucking gas in the overflow portion and in the cavity portion while the valve is kept open for a second time period shorter than a first time period during casting. The heating method further includes a step of heating the casting mold by supplying molten metal into the cavity portion set at the second pressure, and solidifying the molten metal.

A casting mold includes a cavity portion, a gas flow path, and a shut-off valve capable of blocking the gas flow path. An inspection method for the casting mold includes: a step of, when the casting mold is cold, supplying air having a predetermined pressure into the gas flow path while the shut-off valve is closed, and thereafter stopping supply of the air; a step of acquiring a cold time pressure reduction rate of the air in the gas flow path after the supply of the air is stopped; and a step of determining whether the cold time sealing performance of the shut-off valve is good, based on the cold time pressure reduction rate.

A casting mold includes a cavity portion, a gas flow path, and a shut-off valve capable of blocking the gas flow path. An inspection method for the casting mold includes: a step of, when the casting mold is cold, supplying air having a predetermined pressure into the gas flow path while the shut-off valve is closed, and thereafter stopping supply of the air; a step of acquiring a cold time pressure reduction rate of the air in the gas flow path after the supply of the air is stopped; and a step of determining whether the cold time sealing performance of the shut-off valve is good, based on the cold time pressure reduction rate.

The application relates to the technical field of casting and provides a casting mold, a counter-pressure casting method and a low-pressure casting method. The casting mold includes an upper mold insert arranged on an upper mold, a riser cavity is formed in a lower part of the upper mold insert, the riser cavity communicates with a mold cavity, an air pipe is arranged on the upper mold insert, one end of the air pipe is located at a top of the riser cavity, and compressed air can be introduced. The compressed air is introduced into the air pipe in the casting process, an upper part of the riser cavity forms a pressure with the same order of magnitude in a heat-insulating furnace, and the pressure of the riser is transmitted to a far-end defect position through local extrusion.

The following formula represents a gas cavity distribution of a diameter d of gas cavities in a casting product and the number n of gas cavities, where n is greater than or equal to zero, in vacuum die-casting. A constant A is a function of a flow velocity v of a molten material injected into the cavity at a gate. A constant B is a function of a residual gas amount m in the cavity:

In(n)=−Bd+In(A)

For cavity analysis, casting conditions including the flow velocity v and the residual gas amount m are input to a computer, and the computer is caused to calculate a gas cavity distribution according to the formula.