The coil rests on two steel beams of 18 x 18 cm and a length of t = 500 cm with intermediate layers of timber dunnage for increasing the friction. The loaded length from the coil is r = 100 cm. With the extension of (t  r) = 400 cm and the load of 12 t, the diagram in Figure 17 provides the necessary section modulus of just over 390 cm³.
Each beam has a section modulus of 426 cm³ (Table 2). Also the extension of 400 cm is well within permissible limits of 480 cm in this case.
Figure 17: Required section modulus for steel beam bedding
dimensions in cm 
12 x 12 
14 x 14 
16 x 16 
18 x 18 
section modulus in cm³ 
144 
216 
311 
426 
Table 2: Typical section modules of IPB steel beams
