| 摘要 |
PROBLEM TO BE SOLVED: To control the tapping amount per unit time in a wide range by providing a flow regulating nozzle for regulating the flow rate to a desired flow rate and attachable to and detachable from the outlet port of a copper crucible. SOLUTION: A molten metal 1a is tapped down through a nozzle 7 installed to an outlet port 1b, while the floating force is weakened by the power control of upper and lower induction coils 3, 4. The molten metal tapped per unit time is controlled to a desired quantity by the inner surface of the nozzle 7 and the drawing force of an induction coil 8 wound on the circumferential side of a copper crucible 1 at a part where the nozzle 7 is installed. The molten metal is cooled by a gas blown out through an atomizing nozzle 9 under the nozzle 7 to form powder 10. The inside diameter of the nozzle is selected so that the desired tapping quantity is a value smaller than the maximum tapping quantity of the nozzle 7 at start, and the tapping quantity is controlled to a constant tapping by the drawing force of the induction coil 8 in constant tapping, whereby the control range can be extended.
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