Angle Irons

Cold Formed Equal and Unequal Leg

Mild steel angle irons are formed by one of two different methods. Angle irons can either be hot-formed or cold-formed. Both hot and cold formed angle irons can be equal or unequal flanged. The visual difference between hot and cold formed angle irons are shown in the picture to the right while the table below explains these differences.

Equal and unequal angle iron
Nr Cold formed Quality Hot formed Quality
1 Slit material Edges Rounded Edges
2 Equal Thickness Tapered Legs
3 Rounded Outside Corner Square Outside Corner

The cold formed angle iron offers the customer a significant advantage if a need for value adding such as in-line hole punching on cold formed angle irons are done when the slitted material is still in a flat state (not formed yet). Hot formed angle irons have to be punched off-line which may incur additional cost or the possibility may exist that it will not be possible. The flatness and consistent thickness given by the cold formed angle irons holds advantages during fabrication which cannot be achieved with the tapered legs from the hot formed angle iron.

Another advantage that cold formed products have over hot formed products is the fact that there is less scale on the product, making it easier to paint or coat leading to a more aesthetically pleasing end product.

Tubecon manufactures cold formed angle irons at its manufacturing plant in Pretoria. Punching and rolling/cutting to size is offered by Tubecon as well.

Angle irons are used for rails, posts, supports, hangers, flanges, brackets, gate and fence structures to name only a few.

Cold Formed Equal Leg Angles

Equal leg cold formed angle iron

Cold-formed angles (equal leg) dimensions and properties

Designation h*b*t m A ax ay I Ze r rv
mm kg/m 103mm2 mm mm 106mm4 103mm3 mm mm
About x-x and y-y
25x25x1.6 0.59 0.075 7.0 7.0 0.005 0.258 7.85 4.76
2.0 0.73 0.093 7.2 7.2 0.006 0.316 7.79 4.66
2.5 0.89 0.113 7.5 7.5 0.007 0.385 7.71 4.52
3.0 1.05 0.133 7.8 7.8 0.008 0.449 7.62 4.37
30x30x1.6 0.72 0.091 8.3 8.3 0.008 0.376 9.46 5.79
2.0 0.88 0.113 8.5 8.5 0.010 0.463 9.41 5.70
2.5 1.09 0.138 8.7 8.7 0.012 0.567 9.33 5.57
3.0 1.28 0.163 9.0 9.0 0.014 0.665 9.25 5.43
40x40x1.6 0.97 0.123 10.8 10.8 0.020 0.680 12.7 7.84
2.0 1.20 0.153 11.0 11.0 0.024 0.840 12.6 7.75
2.5 1.48 0.188 11.2 11.2 0.030 1.03 12.6 7.63
3.0 1.75 0.223 11.5 11.5 0.035 1.22 12.5 7.51
50x50x2.0 1.51 0.193 13.5 13.5 0.048 1.33 15.9 9.80
2.5 1.87 0.238 13.7 13.7 0.059 1.64 15.8 9.69
3.0 2.22 0.283 14.0 14.0 0.070 1.94 15.7 9.57
3.5 2.57 0.327 14.2 14.2 0.080 2.24 15.6 9.45

r v = minimum radius of gyration

Cold Formed Unequal Leg Angles

Unequal leg cold formed angle iron

Cold-formed angles (unequal leg) dimensions and properties

Designation h*b*t m A ax ay rv
mm kg/m 103mm2 mm mm mm
50x25x2.0 1.12 0.143 17.9 5.05 5.37
2.5 1.38 0.176 18.2 5.28 5.28
3.0 1.63 0.208 18.5 5.50 5.19
75x50x2.5 2.23 0.301 23.9 11.1 10.9
3.0 4.12 0.358 24.1 11.4 10.8
3.5 3.26 0.415 24.4 11.6 10.7
4.5 4.12 0.525 25.0 12.1 10.5
100x50x3 3.40 0.4333 35.1 9.66 10.9
3.5 3.94 0.502 35.4 9.88 10.8
4.5 5.00 0.637 36.0 10.3 10.6
100x75x3.0 3.99 0.508 30.1 17.5 16.3
3.5 4.63 0.590 30.4 17.7 16.2
4.5 5.89 0.750 30.9 18.2 16.0

r v = minimum radius of gyration

Cold formed angles (unequal leg) dimensions and h4roperties (continued)

Designation h*b*t l Ze r l Ze r
mm 106mm4 103mm3 mm 106mm4 103mm3 mm
50x25x2.0 0.038 1.18 16.3 0.007 0.346 6.96
2.5 0.046 1.45 16.2 0.008 0.424 6.90
3.0 0.054 1.72 16.1 0.010 0.500 6.84
75x50x2.5 0.181 3.53 24.5 0.067 1.73 14.9
3.0 0.214 4.20 24.4 0.079 2.05 14.9
3.5 0.246 4.86 24.3 0.091 2.37 14.8
4.5 0.307 6.13 24.2 0.113 2.99 14.7
100x50x3.0 0.467 7.19 32.8 0.085 2.12 14.0
3.5 0.538 8.33 32.7 0.098 2.45 14.0
4.5 0.675 10.5 32.5 0.122 3.09 13.9
100x75x3.0 0.539 7.71 32.6 0.268 4.66 23.0
3.5 0.622 8.94 32.5 0.309 5.39 22.9
4.5 0.784 11.4 32.3 0.389 6.84 22.8
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