5.5　Number of Strands

5.5.1　The number of strand for one caster shall be determined according to the volume of steelmaking furnace，casting time for each heat，strand section and casting speed，and it is also related to the designed output of caster and the matching of caster with smelting cycle.

When casting one kind of section in one caster，the required number of strand shall be calculated as per following formula:

Of which:N—number of strand of one caster；

G—average liquid steel quantity of each heat，t；

F—strand section area，m2；

t—casting time for each heat，min，

vg—average casting speed of section，m/min，

r—specific gravity of strand，preferably take 7.6 t/m3-7.8t/m3.

5.5.2　When casting several sections in one caster，the number of strand shall be calculated respectively，and the maximum strand number of calculation result shall be used as the number of caster strand.

5.5.3　The number of slab caster shall not be more than 2.

5.5.4　The number of strand of large beam blank casters shall not be more than 4，and the number of strand of small beam blank casters shall not be more than 5.