Modified 11 June 2012 by webmaster account

Width Tolerance for Black Flats                                           

Width in mm

Tolerance in mm

20mm to 35mm

+ / - 0.75mm

40mm to 70mm  

+ / - 1.00mm

80mm to 100mm

+ / - 1.50mm

120mm

+ / - 2.00mm

150mm

+ / - 2.50mm

150mm and above

+ / - 2% of nominal width but shall not exceed 10mm

Thickness Tolerance for Black flats up to 150mm wide

Width in mm

Tolerance in mm

Up to 20mm

+ / - 0.50mm

20mm to 40mm

+ / - 1.00mm

40mm and over

+ / - 1.50mm

 Thickness tolerance for flats over 150mm wide

Width in mm

Tolerance in mm

  4mm to 10mm

 + / - 0.05mm

10mm to 20mm

 + / - 0.06mm

20mm to 25mm

 + / - 0.07mm

25mm to 30mm

 + / - 0.08mm

30mm to 40mm

 + / - 0.09mm

40mm to 50mm

 + / - 1.00mm

50mm to 60mm

 + / - 1.10mm

60mm to 80mm

 + / - 1.30mm

80mm and over

 + / - 2.00mm

Tolerances on Black Hot Rolled Square Bars

Size in mm

Tolerance in mm

8mm to 14mm

+ / - 0.40mm

14mm to 25mm

+ / - 0.50mm

25mm to 35mm

+ / - 0.60mm

35mm to 50mm

+ / - 0.80mm

50mm to 80mm

+ / - 1.00mm

80mm to 100mm

+ / - 1.30mm

100mm to 120mm

+ / - 1.50mm

 Tolerances on Black Hot  Rolled Round Bars 

Size in mm

Tolerance in mm

All round bar

+ / - 1.30 % on diameter

Tolerances on Rolled Hollow Sections 

Dimension

Tolerance in mm

Outside dimensions

+ / - 1% with a minimum of + / - 0.5mm

Thickness

+ / - 10 %

Straightness

Shall not deviate by more than 2% of total length measured at the centre of that length.

Tolerances on Black Mild Steel Angle

Dimensional Tolerances

Leg Length mm

Tolerance in mm

Up to and including 50mm

+ / - 1.00mm

Greater than 50mm up to and including 100mm

+ / - 2.00mm

Greater than 100mm up to and including 150mm

+ / - 3.00mm

Greater than 150mm up to and including 200mm

+ / - 4.00mm

Greater than 200mm

+ 6.00mm / - 4.00mm

Thickness Tolerances

Section Thickness mm

Tolerance mm

Up to and including 5mm

+ / - 0.5mm

Greater than 5 up to and including 10mm

+ / - 0.7mm

Greater than 10 up to and including 15mm

+ / - 1.00mm

Greater than 15mm

+ / -  1.20mm

Chemical and Mechanical Tolerances for 43A and 43C (or derivatives)

BSEN10025 S 275JR/ BS4360 43A/ EN10025 FE430 A/ B

MAXIMA

Carbon  

0.250%

Silicon

0.500%

Manganese

1.600%

Phosphorous

0.050%

Sulphur

0.050%

Yield Stress (Y.S.)

> 275 N/mm2

Ultimate Tensile Strength

430 / 470 N/mm2

% Elongation

> 23%

BS6363 1983 GRD 43/36 BS4360 43C Box Section

MAXIMA %

Carbon

0.180%

Silicon

0.50%

Manganese

1.500%

Phosphorous

0.040%

Sulphur

0.040%

Yield Stress (Y.S.)

> 225 N/mm2

Ultimate Tensile Strength

430 / 580 N/mm2

% Elongation

> 22%