KYCR Coil Industries Ltd. - Dhaka Stock Exchange

In the Cold rolling plant the HR Coils are rolled in the room temperature to reduce the thickness.
The degree of reduction depends on the number of passes, i.e. the number of times the sheet is
rolled. For example the 1.8 mm HR sheet may be converted into CR sheet of following thickness
in mm.
0.156 0.160 0.170 0.176 0.180 0.186 0.190 0.196 0.200 0.210
If the thickness of the sheet is 2.0 mm or 1.6 mm then reduction of thickness may take place as
follows.
For 1.6 mm thick sheet
0.120 0.125 0.130 0.140 0.150
For 2.0 mm thick sheet
0.220 0.230 0.240 0.250 0.260 0.270 0.280 0.290 0.300 0.310
0.320 0.330 0.340 0.350 0.360 0.370 0.380 0.390 0.400
There is no scope of change of the original width i.e. 840 mm in the first case and the original
width of CR coil would be carried throughout the entire transformation. So it is clear that the
width of the galvanized sheet would be identical as that of the CR coil. Once galvanization
process is complete, the sheet is passed through the corrugation machine and then effective
width of the coil is reduced by some proportion as explained below.
840 mm
720 mm
(approx.)
The reduction of width will depend on the depth of corrugation, but we can assume a reduction
of 12%-15% of the original width. The depth of corrugation is varied as per the requirements of
the final width. However it may be mentioned that for effectiveness, a minimum corrugation is
required beyond which the sheet will not serve its purpose of protection.
The range of thickness for the CR sheet starts from as low as about 0.095 mm and ends at 0.45
mm depending on the thickness of original HR sheet used. The lower thickness variety is
generally used for sidewalls, boundaries etc. whereas comparatively thicker materials are used
for construction of roof. Sheets are available in five lengths between 6 ft and 10 ft, with
increment of 1 foot. Width of the sheet also varies from 27 inch to 32 inch as explained above.
Generally the width increases with the thickness as we can see that 1.6 mm HR has got a width
of 780/800 mm whereas width of 2.0 mm HR sheet is 915 mm.
Normally the sheets are sold in pieces, Baans, and Pcs Tons. Baan is a unit exclusively used for
corrugated sheets, which denotes a running length of 72 feet. In case of 6 ft sheet, 12 sheets
make a Baan. However, for 7 feet sheets, only 10 sheets make a Baan using rounding off
technique.