From scrap selection to properties measurement of final product, our engineer and technical personnel implement their hone skill for yielding best quality product. We know, thousands life will suffer if a structure will fail. So, whatever it costs, quality of the product is our sole concern. In previous section, harmful effects of several allowing elements were discussed. Entire harmful elements generally come from scrap materials, which reveal the importance of scrap segregation. Engineers from our quality control department conduct test (both visual and chemical) the received scrap materials and select better quality scrap for melting operation.
During melting our engineers carefully monitor charged materials so that there rise no chance to melt bad quality scrap. QC department has done the chemical analysis and provide necessary direction for analysis element addition. When casting of melt is finished, chemical analysis is again accomplished and if billets attain optimal chemical composition, QC department certifies them for rolling.
There are some key factors, which play a vital role over properties of final product, are carefully controlled by our engineers. At the very commencement, temperature of the billets should be above 1100oc which is always checked by QC dept. If billets do not reach the temperature they won’t have proper diameter as well as, tensile property of final product will be affected. Roll gap, rolling pressure, roller dia, etc are strictly controlled by the engineers of QC dept.
Cooling chamber is a critical step of production procedure. Here water is used to change the outer structure of deformed bar which will increase the strength drastically, whereas, soft core will cater sufficient toughness, ductility and elongation.
Billets should have temperature above some critical value before entering the chamber, as well as, below a optimal value after leaving. Both of these are measured by QC department with the help of a pyrometer. Water pressure, flow rate and mill speed determines the thickness of outer martensitic layer. Slight alteration of any of these will severely affect the properties of final product. Key properties like Yield Strength, Ultimate Tensile Strength, % Elongation, Toughness, Ductility etc. will be sacrificed while these factors are uncontrolled during water treatment. In BSRML, these factors are controlled by our trained engineers of QC department with greatest care.
After accomplishment of rolling, tensile test and microstructure analysis are conducted by QC department and products which have obtain necessary properties are then certified for shipment.
Strength is not the only characteristics, by which, the quality of the deformed bar can be ensured. Ductility, toughness, fracture strength, malleability, %elongation etc are very important factor, which should be considered during the manufacturing period of steel, to ensure the higher life time of infrastructures where, deformed steel bars are used as reinforcing agent during manufacturing. Our quality team always looking for to improve the combination of four or more properties at least, so that, we are capable of offering better quality steel of 40, 60 and 75 grades of 8,10, 12, 16, 20, 25 & 32 mm diameter. “Ensure better quality of the products” is the main motto of our company.
