To prevent the oxidation of molten metal and to attain a continuous stable production of a formed product by bypassing the molten metal from a supplying pipe line to a holding furnace during time when the supplement of the molten metal into a cavity is not needed, in forming of the low m.p. molten metal.
A molten metal supplying apparatus 100 is provided with the holding furnace 10 for the molten metal M, a molten metal pump 20 for discharging the molten metal M from the holding furnace 10, a gate valve 50 for controlling communication and shut-off of the discharged molten metal M into a die cavity 2 and a pipe line 40 for connecting the molten metal supplying pump 20 and the gate valve 50. This apparatus is constituted to be provided also with a returning pipe line 60 for returning back the molten metal M flowing into the gate valve 50 to the holding furnace 10. When the molten metal M is not supplied and filled into the die cavity 2. In this case, the supplying pipe line 40 connecting the holding furnace 10 with the gate valve 50 and the returning pipe line 60 are made flexible only at near the gate valve 50 and the outsides are heat insulated with heaters 80b and the remaining parts are made to fixed type double pipe lines for passing the molten metal M in the inside and a heating medium on the outside.
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