Method for the operation of a low-pressure metal-casting apparatus and a low-pressure metal-casting apparatus for this purpose

摘要

The invention relates to a method for operating a low-pressure metal-casting apparatus, particularly one for brass or copper. In this arrangement, a metal melt (2) is held in reserve in a closed melting furnace (10) and a die (5) placed on the upper end (31) of at least one rising pipe (3) which dips into the melt (2) and is passed out of the furnace (10) at the top can be filled with metal melt (2) through the said rising pipe by raising the pressure in the interior (12) of the furnace, and, after the metal melt (2) delivered to the die (5) has solidified, the molten metal level (20) in the rising pipe (3) is lowered again by reducing the pressure in the furnace (10), the filled die (5) is moved away from the rising pipe (3) and a new, empty die (5) is placed on the rising pipe (3). The new method is characterised in that as the molten metal level (20) in the rising pipe (3) falls or after it has fallen, a fluid medium (43', 44') which binds and/or displaces the atmospheric oxygen situated above the molten metal level (20) in the rising pipe (3) is pumped into the interior (30) of the upper part (31) of the rising pipe (3). The invention furthermore relates to a low-pressure metal-casting apparatus. <IMAGE>