Lead Tower Assembly
The lead tower consists of three identical, 15-foot (4.6 m) sections that must be assembled and
attached to the crane boom nose. The lead tower will be assembled immediately in behind the
center rear of the crane carrier.
Perform the following procedure to assemble the lead tower:
Clear a 25 by 100-foot (7.6 x 30.5 m) area immediately to the rear of the crane's
carrier for assembling the lead tower.
The three lead sections are identical and interchangeable. One
end of each section features tapered dowels, the other end has no
Ensure the Load Moment Indicator (LMI) system on the crane is configured for
Rear Hoist, Outrigger Position 100%, and Two (2) Parts of Line.
Ensure the top lead section is on its side, within a few feet of the rear of the crane,
on wood blocking spaced three feet (0.9 m) from each lead section end, and with
the dowel end facing the crane.
Loosen the assembled bolts, washers, and nuts securing the retaining blocks to
the top lead section.
The pile line (aux. hoist) of the crane along with the wire rope
lifting sling and nylon lifting sling can be used to position and align
the lead sections during assembly. The five-foot bar with hickey
can also be used to aid in lead section alignment.
Attach the two nylon lifting slings to the middle lead section. Use the pile line (aux.
hoist) of the crane to position and align the middle lead section with the top lead
section and push the ends together. Ensure the dowels on the middle section
mate with the holes in the top section and the hammer side with the larger tubular
rails on each lead section faces in the same direction.
Install the joint retaining blocks with assembled bolts, washers, and nuts. Be sure
the tapered end of the joint retainer block is on the inside against the weld and that
the nuts are facing downward (i.e. towards the ground with lead tower attached to
boom). Tighten the bolts and nuts simultaneously or alternately on each side in
order to draw the two sections together. Torque the joint bolts and nuts to 680 ftlb
Ensure the middle lead section is also resting on wood blocks spaced three feet
(0.9 m) from each lead section end.
Attach two nylon lifting slings to the bottom lead section. Use the pile line (aux.
hoist) of the crane to position and assemble the bottom lead section to the middle
Use the pile line (aux. hoist) of the crane and the nylon lifting slings to lift the
assembled lead tower in order to place additional wood blocks under the tower,
raising it 12 to 16 inches (30-40 cm) above the ground.
Change 1 H-41