Wednesday, February 08, 2017

Tor Steel acceptance criteria

TOR- STEEL:

The acceptance criteria can be broadly classified into three categories as under:-

  1. Chemical composition
  2. Weight
  3. Physical properties.

1.Chemical composition:

The product analysis shall be as follows:

Constituent
 Max. %        (Fe-415)
Max. % 
(Fe-500)
Max. %     (Fe-550)
% age Variation limits
Carbon
0.30
0.30
0.30
0.02
Sulphur
0.060
0.055
0.055
0.005
Phosphorus
0.060
0.055
0.050
0.005
Sulpur + Phosphorous
0.11
0.105
0.10
0.010

Here, maximum carbon content permitted is only 0.25 %

 

2.Weight:

The weight per meter shall correspond to the following:



      Nominal size                         in mm
 Weight                     Kg/ meter
Acceptable range                   Kg/ meter
6
0.22
0.228-0.206
8
0.39
0.423-0.367
10
0.62
0.680-0.574
12
0.89
0.932-0.844
16
1.58
1.66-1.50
20
2.47
2.54-2.39
22
2.98
3.07-2.90
25
3.85
3.97-3.74
28
4.84
4.98-4.69
32
6.32
6.51-6.13

 

3.Physical properties:

The following shall be satisfied:


Test
Tor-40
Tor-50
0.2% proof stress
415 N/mm2 min.                     (4230 kg/cm2)
500 N/mm2 min.                           (5100 kg/cm2)
Tensile Strength
10% more than the actual but minimum 485 N/mm2
10% more than the actual
Max. elongation
14.5%
12.0%

 

Following routine test should be performed on samples selected and prepared as per CL.8.1 of  IS: 1786-1985:-  


  • Tensile Test
  • Bend Test
  •  Rebend Test

Raw & finished steel products include:-

  •  Semis- Ingots, Slabs, Blooms, Billets, Squares, etc.
  • Structural- Channels, Beams (I-Sections, Angles, etc
  • Rolled products- Bars, Rounds, Ribbed Torsteel Bars, Flats, etc.
  • Flat product- Plates, Hot Rolled Sheets Skelp and Coils, Cold Rolled Sheets and Coils High Silicon Sheets.
  • Track- materials- Crossing Sleeper Bars, Fish Plate, Bearing Plate Bars, Pressed Steel Sleepers, Heavy Rails, Light Rails, Wheel, Axles and Wheel Sets.
  • Special items- Tinpulates- Electrolytic, Large Diameter Steel Tubes- ERW Spirally Welded Pipes, Galvanised Sheets, High Conductivity Rails, Crane Rails, etc.

Some of the major manufactures of steel products in the country are:-

  • SAIL- Steel Authority of India Limited - a Government of India Undertaking.
  • TISCO- Tata Iron & Steel company
  • Vishakapatnam steel plant
  • RATHI
  • Bhilai
  • Haldia