A die casting method includes a step of supplying molten metal to a plunger sleeve, and a step of advancing a plunger in the plunger sleeve, to inject the molten metal into dies. In the step of injecting the molten metal into the dies, the plunger is once retracted before being advanced, and the plunger is kept accelerated until the plunger reaches a target maximum speed when the plunger retracted is advanced.

A casting unit for a die casting machine has a casting container with a casting chamber, a casting piston, which is arranged in an axially movable manner in the casting chamber, a melt bath connection opening, a melt inlet channel from the melt bath connection opening to the casting chamber, a melt outlet channel, which leads out of the casting chamber separately from the melt inlet channel, and a shut-off control valve for the melt inlet channel. The shut-off control valve has a valve main body arranged on the casting container, a valve seat and a valve closing body. The valve main body is held on the casting container at a lateral valve assembly region of the casting container in a manner accessible from the outside and includes the melt bath connection opening, and/or the casting piston is of a spool type, and the shut-off control valve is located with its valve closing body in the melt inlet channel at a flow-technical distance from the melt bath connection opening on the one hand and from the casting chamber on the other hand.

Embodiments of the invention are directed to a rotor for a molten metal pump and a molten metal pump including the rotor. The rotor has a main body and a top comprised of a material that is at least twice as hard as the main body. The top, among other things, may form a first portion of each rotor blade wherein the first portion directs molten metal into a pump chamber or other structure in which the rotor is mounted.

Embodiments of the invention are directed to a rotor for a molten metal pump and a molten metal pump including the rotor. The rotor has a main body and a top comprised of a material that is at least twice as hard as the main body. The top, among other things, may form a first portion of each rotor blade wherein the first portion directs molten metal into a pump chamber or other structure in which the rotor is mounted.

This invention provides an improved method and apparatus for controlling the flow of molten metal alloys and, in particular, to a method to finely control the delivery rate of liquid aluminum alloys and the liquid fraction of semi-solid aluminum alloys. The apparatus and method described herein provide for the pumping of liquid metal alloys in a precise and controlled manner. By controlling the heat flow through a section of the pump piston, the pump chamber, the porous liner of the pump chamber and the metal alloy charge, the present invention provides a means to deliver liquid metal alloys at high pressure through one or more exit ports.

The present invention is directed to a molten metal pump comprising an elongated pumping chamber tube with a base end and an open top end. A shaft extends into the tube and rotates an impeller therein, the impeller rotates proximate the base end. The tube has a diameter at least 1.1 times the diameter of the impeller. The pumping chamber tube preferably has a length at least three times the height of the impeller. The base end includes an inlet and the top end includes a tangential outlet. Rotation of the impeller draws molten metal into the pumping chamber and creates a rotating equilibrium vortex that rises up the walls of the pumping chamber. The rotating vortex adjacent the top end exists the device via the tangential outlet.

The present invention is directed to a molten metal pump comprising an elongated pumping chamber tube with a base end and an open top end. A shaft extends into the tube and rotates an impeller therein, the impeller rotates proximate the base end. The tube has a diameter at least 1.1 times the diameter of the impeller. The pumping chamber tube preferably has a length at least three times the height of the impeller. The base end includes an inlet and the top end includes a tangential outlet. Rotation of the impeller draws molten metal into the pumping chamber and creates a rotating equilibrium vortex that rises up the walls of the pumping chamber. The rotating vortex adjacent the top end exists the device via the tangential outlet.

A casting device of a large non-ferrous metal thin-walled structural component. A liquid outlet of the casting device is communicated with a casting sand box. The casting device comprises an L-shaped liquid storage cylinder, a pressure supplying cylinder, and a crystallization treater. Protective gas with the first gas pressure can be inflated into the top of the L-shaped liquid storage cylinder. The pressure supplying cylinder and the L-shaped liquid storage cylinder are integrally connected to form a U-shaped tube connector. Protective gas with the second gas pressure can be inflated into the top of the pressure supplying cylinder. A liquid inlet of the crystallization treater is communicated with the pressure supplying cylinder while a liquid outlet is communicated with the pouring system and the mold cavity. The crystallization treater is provided with a grain refining mechanism.

A casting device of a large non-ferrous metal thin-walled structural component. A liquid outlet of the casting device is communicated with a casting sand box. The casting device comprises an L-shaped liquid storage cylinder, a pressure supplying cylinder, and a crystallization treater. Protective gas with the first gas pressure can be inflated into the top of the L-shaped liquid storage cylinder. The pressure supplying cylinder and the L-shaped liquid storage cylinder are integrally connected to form a U-shaped tube connector. Protective gas with the second gas pressure can be inflated into the top of the pressure supplying cylinder. A liquid inlet of the crystallization treater is communicated with the pressure supplying cylinder while a liquid outlet is communicated with the pouring system and the mold cavity. The crystallization treater is provided with a grain refining mechanism.

A system for melting metals for casting includes one or more arc welding power supplies configured to provide one or more arc welding outputs, and one or more electrodes operatively connected to the one or more arc welding outputs. A solid metal holder is configured to hold a solid metal to be melted by one or more arcs formed between the one or more electrodes and the solid metal to generate a molten metal. A container is positioned proximate the solid metal holder to receive the molten metal. A robot is proximate both the container and a mold and/or a die cast machine. The robot has an arm configured to manipulate the container containing the molten metal and pour the molten metal from the container into the mold and/or the die cast machine for casting.