• Raw Materials are unloaded heat-number wise and size wise separately in the raw material yard and the identification marks are allotted.
• Chemical testing are done on sample size and acceptable norms for inspection and testing of raw material and records are maintained in raw material yard and analysis register. Analysis results of test certificates accompanying with the raw material are be noted in the same register.
• Visual surface checking of each piece of billets are done. Cracks, blow holes, pin holes, deep grooves, overlapping etc. in billets are removed by grinding process. Unacceptable pieces are kept separately showing as “Rejected” on boards.
• Billets are cut into required length of finish products heat-wise and charged into Heated Furnace where continuous heating is done by maintaining the required temperature. Heating time varies according to size of billets, for eg., 100x100 billets require 4 hrs whereas 75x75 billets require 3 hrs.
• Reduction ratio 1:10 minimum are maintained.
• During rolling dimension, surface and length of sections are checked in 30 minute time interval and advised the foreman to rectify the defects, if any. Rolling are done heat number wise of raw material.
• Rolled sections are kept at Cooling Bed for natural cooling and after that shifted to Shearing Machine for end cutting & required length cutting, then shifted to finish stock yard, heat-wise. This process is covered in DS/9-2 recorded in QR/10-7.
Once the final product is ready, select the sample for Chemical, mechanical, dimension and unit-weight testing as per the factory Laboratory.
• Mechanical test : Laboratory
• Chemical test : By wet chemical analysis method as per IS:228
• Dimension : By vernier caliper, micro meter, radius gauge, angle projector, measuring tape.
• Surface : Each piece shall be checked visually.
• Unit weight : By weighing Machine.
Above inspection reports are maintained in Laboratory & Factory records.