Section II. WHEEL RIMS
holding the tire in place. This type of rim is standard
32-4. Drop Center. The drop center rim (fig. 32-4) is
equipment on 3/4-ton 4 x 4 trucks.
made . n one piece and is fastened to the wheel
permanently. Its important feature is a well that permits
32-6. Safety. Safety rims (fig. 32-6) are similar to drop
the mounting and demounting of tires. Bead seats are
tapered to match a corresponding taper on the beads of
center rims. The major difference is that safety rims
the tire. Drop center rims are used generally on smaller
have a slight hump at the edge of the bead ledge that
vehicles, such as 114-ton 4 x 4 trucks.
holds the bead in place when the tires go flat. These
rims currently are used on many passenger cars and
32-5. Semidrop Center. The semidrop center rim (fig.
32-5) is also fastened permanently to the wheel. This rim
has a shallow-well, tapered-head seat to fit the taper of
32-7. Split. A split rim (fig. 32-7) is a rim that has a
the beads of the tire. It also has a demountable flange or
removable bead seat on one side of the rim. The seat is
side ring, which fits into a gutter on the outside edge of
split to allow for its removal so tires can be changed.
Some bead seats also require the use of a lockring to
retain the seat. These rims are found usually on large
Figure 32-4. Drop Center Rim
Figure 32-5. Semidrop Center Rim.