Figure 12-49.—Typical pile-driving operation.
Figure 12-50.-Assembly of 10- and 20-foot lead sections.
section bolts for tightness at the beginning of each
pile-driving shift.
The types of leads used in the NCF are swinging,
underhung, extended four-way, and spud leads.
Swinging Leads
Swinging leads are assembled facedown on the
ground by bolting the 15-foot tapered section to the
selected intermediate sections. A single crane line
holds the pile-driving hammer that is slipped into and
guided by the rails of the swinging leads. This lead is
hung from the crane boom with a second single line
from the crane. The lead is spotted on the ground at
the pile location,
normally with stabbing points
attached to the bottom of the leads, and held plumb or
at the desired batter with the second single crane line.
Short swinging leads are often used to assist in driving
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