Coils to be annealed are transferred from the cold mill bay to the hydrogen batch annealing department by high speed conveyor. The batch annealing facility, which uses bell annealer technology, has an annual capacity of 55,000 tons and processes cold rolled product 0.010–0.080 inch thick, 36–72 inches wide in coils with an OD of 46–85 inches and a coil ID of 24 inches. The annealer has 21 work bases, 11 heating bells and 11 cooling bells.
The annealing furnaces are fired by natural gas with a total combustion rating of 6 million BTU/hour. Maximum charge weight is 147 tons with a stack height of 224.5 inches. The number of coils per base varies between three and five. Load space diameter is 86.5 inches.
A typical annealing cycle is 39 hours (heating 24 hours, cooling 15 hours). The temperature ceiling inside the heating bell is 1,562°F, with a temperature range inside the inner cover of 536–1,382°F.
Ancillary facilities include two 45-ton-capacity coil upenders/downenders and two 45-ton-capacity magnets for coil handling.
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