Specifications:
Qty : 200,000 MT monthly
Grade: B500B/3SP
Process of manufacture:
process route: EAF/BOF---LRF---CCM.
Input raw material: Hot DRI/HBI + Scrap + Internal virgin scrap(as and when required).
Killing practice: Silicon killed/Aluminum killed.
Metallurgical requirements:
Color code: As agreed before contract
Range: Min% - Max%
C 0.19 - 0.22 , Mn 0.65 - 0.80 , Si 0.15 0.30 , S 0.20 , P 0.035 , Cr 0.10 , Ni 0.10 , Cu 0.05 , Sn 0.015 , B 0.0008 , As 0.015 , Sb 0.01 , N2ppm 70
CE : 0.48 max (Aim 0.31-0.36)
CE= C+ Mn/6+ (Cr +Mo +V) /5+(Cu +Ni) /15
Permissible variation in analysis for individual chemical elements will be as per ASTM A29.
Internal soundness:
- One macros sample shall be checked for every 3 heats per sequence.
- Billet macrostructure should be appropriate to produce rolled product as per C2S2R2 ASTM E381.
- Free from harmful subsurface defects like blow / pin holes, and cracks which can affect the end product quality.
- Central looseness / piping: 4mm max.
- No visible defect (piping, pin holes, crack) should be on the cross section of both ends.
Surface Quality:
Billet shall be supplied free from harmful surface defects like longitudinal/transverse cracks, pinholes, slag patches, mechanical mark etc., which can affect surface quality of the end products, Mechanical/Scratch marks with a maximum depth of Less Than = 1mm depth are allowed, defect more than 1mm should be removed by smooth grinding and width of grinding and width of grinding and width of grinding and width of grinding should be at least 6 times of depth.
Size and dimensional tolerances:
Section in mm: 150*150 - 160*160
D1-D2 in mm (max) 10
Side Tol in mm +/-4
Length in meter 12
Length Tol in mm +/-50
Bulging 4 mm max
Bend in mm 5mm/m & 60mm in entire length, no end bend allowed
Ends Cut deviation 5mm max.
General :
- Billet ends will be Gas cut which should be straight.
- Burrs if present should not be more than 5 mm of thickness and 25 mm width
- Billet should be from current production and rust if present should be superficial
Certification:
The test certification will contain
- Supply condition
- Process of manufacturing
- Steel grade
- Heat number(cast number) , length, no of pieces and weight
- Chemical composition
- Declaration for free from radioactivity
Identification:
- Heat no./grade/length will be painted on one end of each billet with a specific color code Please let us know if there is any additional information you require from our end to proceed with this inquiry.
NO Parameters Unit Specs
1 T.Fe % 65.00 Min
2 SiO2 %
3 Al2O3 % 6.00 Max
4 CaO % 0.65 Typical
5 MgO % 0.04 Typical
6 P % 0.06 Max
7 S % 0.0040 Max
12 Moisture % 2.50 Max
21 Less Than 5.0 mm % 1.0 Max
22 T.I.(+6.3mm) % 94.0 Min
23 A.I.(-0.5mm) % 3.0 Max
24 CCS Kg/P 280 Min
26 Porosity % 23% Min
28 Mean Size mm 13 mm
