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COLD RE-ROLLING MILL
A development of the principal of using Small Working Rolls are illustrated by
the Four - Roll Arrangement " Fig 1 D " in which the metal passes between the two
smaller rolls, which are supported by the two large rolls. The most popular type
in rolling is the first.
SHEETS :
Steel or Non-Ferrous metals are sheets of Metal varying in thickness from
0.25 in down to 0.02 in or less in width from 2 ft or 4 ft in various length.
Sheet Rolling as opposed to Strip is rolled in separate pieces or sheets of
limited length.
Strips:
2 ft width metal and is rolled from Coils, Roll Strip as wide as 4 ft and wider
in coils, from which flattened metal is cut to length in sheets.
In " Fig 1 C " three rolls are shown in an arrangement known as " 3 High ".
This provides for Reversible working and commonly adopted for Section and Bar Mills
also Cold Rolling long length of strip in coils.
The centre roll in a 3 High Assembly is smaller diameter than the top and bottom
rolls, thereby obtaining the technical advantages resulting from using a roll of
minimum diameter, the load due to the resistance of the metal to deformation by
the larger top and bottom rolls.
A further elaboration of this system is given by the next three diagrams " Fig 1 E”
showing the Six Rolls or " CLUSTER " Mill.
" Fig 1 F " the 12 Rolls or " ROHN " Mill.
" Fig 1 J" the SENDZIMIR assembly which has a 12 Rolls Arrangement with the final
" back up " Eight Lines of Roller Bearings.
Long continuous stock is frequently rolled in trains of mills in the as " TANDEM "
or " CONTINUOUS " as illustrated in " Fig 1 H ", this diagram shows a Three Stands
Mill each stand being of the 2 High, 3 High and 4 High types.
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