An injection device of light metal injection molding machine and an injection control method thereof are provided, in which a melt in a supply unit is supplied into an injection unit through a communication passage, a plunger of the injection unit is retracted to measure the melt, the communication passage is closed, and the plunger is advanced to inject the melt into a mold device through an injection nozzle of the injection unit. After the injection and before the measurement, the plunger is advanced under a pressure at which the melt does not come out from the injection nozzle to make the melt in the injection unit flow back into the supply unit through the opened communication passage.

A foundry casting system and process employs an inert gas delivery and recovery system for casting parts which results in cast parts having improved metalurgical characteristics. The system may be employed in sand, die casting, semi-permanent and permanent casting environments. Pressurized inert gas may be diffused into the mold before, during and after the metal pouring step. The resulting casting is free from oxides and dissolved hydrogen gas as they are removed from the mold cavity. This results in higher quality castings as well as increased production output due to faster cooling cycles.

A foundry casting system and process employs an inert gas delivery and recovery system for casting parts which results in cast parts having improved metalurgical characteristics. The system may be employed in sand, die casting, semi-permanent and permanent casting environments. Pressurized inert gas may be diffused into the mold before, during and after the metal pouring step. The resulting casting is free from oxides and dissolved hydrogen gas as they are removed from the mold cavity. This results in higher quality castings as well as increased production output due to faster cooling cycles.

Provided are a decompression shut-off valve device having high responsiveness and a method for controlling the same. The decompression shut-off valve device 10 includes an on-off valve 30, a detection pin 50, and an interlocking member 60 which operates the on-off valve 30 by displacement of the pressure-receiving section 52, a valve chamber 31, an accommodating chamber 17, and a cylinder 40 which accommodates an enlarged diameter section 37 provided in a rod section 33 of the on-off valve 30. The rod section 33 is slidably held through a second partition wall 18, and a rod end portion 36 of the rod section 33 is connected to the detection pin 50 via the interlocking member 60. The cylinder 40 is partitioned into a small diameter low-pressure chamber 80, and a large diameter high-pressure chamber 70 in which the working fluid having a higher pressure than the low-pressure chamber 80 is accommodated.

Provided are a decompression shut-off valve device having high responsiveness and a method for controlling the same. The decompression shut-off valve device 10 includes an on-off valve 30, a detection pin 50, and an interlocking member 60 which operates the on-off valve 30 by displacement of the pressure-receiving section 52, a valve chamber 31, an accommodating chamber 17, and a cylinder 40 which accommodates an enlarged diameter section 37 provided in a rod section 33 of the on-off valve 30. The rod section 33 is slidably held through a second partition wall 18, and a rod end portion 36 of the rod section 33 is connected to the detection pin 50 via the interlocking member 60. The cylinder 40 is partitioned into a small diameter low-pressure chamber 80, and a large diameter high-pressure chamber 70 in which the working fluid having a higher pressure than the low-pressure chamber 80 is accommodated.

A method for delivering a flowable material into a mold or to infiltrate a preformed component, a fiber preform, or a green body includes: providing a crucible having a body configured as a reservoir to hold the flowable material; adding a metal, a metal alloy, or combination thereof into the body of the crucible, the metal or metal alloy having a predetermined melting point; heating the crucible with the metal or metal alloy contained therein to a temperature that is at or above the melting point of the metal or metal alloy; allowing the metal or metal alloy to melt to form the flowable material; and creating a siphon such that the molten metal or metal alloy flows from the body of the crucible to infiltrate the preformed component or to fill the mold.

A method for delivering a flowable material into a mold or to infiltrate a preformed component, a fiber preform, or a green body includes: providing a crucible having a body configured as a reservoir to hold the flowable material; adding a metal, a metal alloy, or combination thereof into the body of the crucible, the metal or metal alloy having a predetermined melting point; heating the crucible with the metal or metal alloy contained therein to a temperature that is at or above the melting point of the metal or metal alloy; allowing the metal or metal alloy to melt to form the flowable material; and creating a siphon such that the molten metal or metal alloy flows from the body of the crucible to infiltrate the preformed component or to fill the mold.

In a molten metal pump, which includes a pump chamber portion and a drive unit and drives molten metal in a pump chamber of the pump chamber portion by the drive unit for discharging and sucking, the pump chamber portion has an outer cylinder and an inner cylinder detachably housed in the outer cylinder, the outer cylinder is configured as a bottomed cylindrical body having an outer cylinder bottom wall and an outer cylinder side wall, the inner cylinder is configured as a bottomed cylindrical body having an inner cylinder bottom wall and an inner cylinder side wall, a ring-shaped spacer, which is interposed between an inner surface of the outer cylinder bottom wall and an outer surface of the inner cylinder bottom wall in a sealed state and in a detachable manner, is further provided.

In a molten metal pump, which includes a pump chamber portion and a drive unit and drives molten metal in a pump chamber of the pump chamber portion by the drive unit for discharging and sucking, the pump chamber portion has an outer cylinder and an inner cylinder detachably housed in the outer cylinder, the outer cylinder is configured as a bottomed cylindrical body having an outer cylinder bottom wall and an outer cylinder side wall, the inner cylinder is configured as a bottomed cylindrical body having an inner cylinder bottom wall and an inner cylinder side wall, a ring-shaped spacer, which is interposed between an inner surface of the outer cylinder bottom wall and an outer surface of the inner cylinder bottom wall in a sealed state and in a detachable manner, is further provided.

An apparatus for low-pressure casting includes a furnace wall bounding a furnace chamber, a melting crucible unit located in the furnace chamber, a heating device for heating the melting crucible unit, and at least one pressurizing unit for applying overpressure to the melting crucible unit. The furnace chamber in a top view has a length which is greater than its width, so that the furnace chamber has an elongated shape in a longitudinal direction, wherein preferably several riser pipes extending vertically are distributed roughly evenly over around 60% to 95% of the length in the longitudinal direction of the melting crucible or crucibles.