What are the shapes of graphite crucibles? How is their capacity calculated?

Graphite crucibles can be classified into regular type and irregular type based on their shape.

Capacity Calculation Method: The capacity is indicated using the “番 (#)” system from JIS (Japanese Industrial Standards).

1番 (1#): Equivalent to the capacity to dissolve 1 kg of brass.

For example, a 300# graphite crucible:

• Holds about 300 kg of molten copper
• Holds about 100 kg of molten aluminum

Regular Graphite Crucibles: These are made according to standard specifications, with an outer diameter to height ratio of approximately 0.7 to 0.8:1. They range in sizes from 1# to 2500#.

Irregular Graphite Crucibles: These include various types such as:

• Long Type: More elongated than the standard type, with an outer diameter to height ratio of about 0.6 to 0.7:1. Capacity ranges from #15 to #620.
• Bowl Type: Larger outer diameter, with an outer diameter to height ratio of about 1:1. Capacity ranges from #250 to #5200, capable of melting aluminum alloys up to 1.5 tons.
• Spout Type: Resembles the long type crucible but with a spout for pouring. Capacity ranges from #50 to #1800.
• Furnace Type: Cylindrical and elongated, with an outer diameter to height ratio of about 0.6:1. Capacity ranges from #60 to #5000.