The tolerances which are normally acceptable according to IS : 811-1987 and/or other equivalent standards for the cold rolled sections are as follows:
1) Thickness Tolerance (IS : 852-1985)
a) Hot Rolled Sections
Thickness margin (in mm)
Tolerance on thickness (in mm)
≤ 2.00
±0.13
> 2.00 ≤ 2.50
±0.14
> 2.50 ≤ 3.00
±0.15
> 3.00 ≤ 4.00
±0.17
> 4.00 ≤ 5.00
±0.18
> 5.00 ≤ 6.00
±0.20
> 6.00 ≤ 8.00
±0.22
b) Cold Rolled Sections
Thickness margin (in mm)
Tolerance on thickness (in mm)
≤ 0.40
±0.04
> 0.40 ≤ 0.60
±0.05
> 0.60 ≤ 0.80
±0.06
> 0.80 ≤ 1.00
±0.07
> 1.00 ≤ 1.20
±0.08
> 1.20 ≤ 1.60
±0.10
> 1.60 ≤ 2.00
±0.12
> 2.00 ≤ 2.50
±0.14
> 2.50 ≤ 3.00
±0.16
2) Cross-sectional Dimensional Tolerance*
a) For dimensions between radius and edge (E.g. C and D in Figure)
Thickness(mm)
Dimension Range (in mm)
< 40
> 40 ≤ 100
> 100 ≤ 200
> 200 ≤ 400
> 400
≤ 1.5
0.50
0.50
0.75
1.00
1.5 ≤ 3
0.75
0.75
1.00
1.25
1.75
3 ≤ 6
1.00
1.00
1.25
1.75
2.00
6 ≤ 8
1.25
1.50
2.00
2.50
b) For dimensions between radii (E.g. A and B in Figure)
Thickness(mm)
Dimension Range (in mm)
< 40
> 40 ≤ 100
> 100 ≤ 150
> 150 ≤ 200
> 200
≤ 1.5
0.75
0.75
1.00
1.5 ≤ 3
0.80
1.00
1.25
1.50
3 ≤ 6
1.00
1.25
1.50
1.75
2.00
6 ≤ 8
1.25
1.50
1.75
2.00
2.25
* These tolerances apply to the whole length of the sections with the exception of around 100 mm length on either ends, which are influenced by the cut.
3) Straightness Tolerance
1/600 (0.16% of total length) on X-X and Y-Y axes
4) Torsion Tolerance
2°/1000 mm length
5) Length Tolerance
Length (in mm)
Tolerance (in mm)
< 3000
± 1.0
> 3000 ≤ 6000
± 1.5
> 6000 ≤ 10000
± 3.0
6) Angle Tolerance
Length of smallest side of angle (in mm)
Tolerance (in mm)
< 30
± 2°
> 30 ≤ 50
± 1° 45’
> 50 ≤ 80
± 1° 30’
> 80 ≤ 120
± 1° 15’
> 120
± 1°
Closer tolerances than the above mentioned tolerances can be achieved as per the requirement of the customer.
