Ribs, lugs and holes often occur in odd numbers and should be aligned to show the true relationship of elements. Figure 3 shows the normal practice of drawing  revolved sections of ribs, holes, and lugs. True projection of the ribs (A) show the pair on the right shortened suggesting that they does not extend to the outer edge. Section (B) shows symmetry. Rib part is not sectioned. At (C), the lugs and holes are aligned showing the holes at their true radial distance from the axis. Ribs are never shown sectioned (hatched). 

Figure 3. Practice of drawing  revolved sections of ribs, holes, and lugs

The practice of drawing revolved sections  of pulleys  having web and spokes are shown in figure 4. . Pulley A has a solid web connecting the hub and rim. Pulley B has four spokes.  Even though the cutting plane passes through two of the spokes, the sectional view of B must be made with out hatching the spokes in order to avoid the appearance of a solid web.

Figure 4. representation of pulleys having we and spokes.