While the Tie
Bars may look as wire from the ground, they are actually substantial
tubes.
Pulling the Tie
Bars to the Jib attachment points is done using a hydraulic tightening
device, very similar to the system used in Slip Forms.
The ends of the
red beam bolts onto the outer ends of the left and right Jib Tie
Bars.
The gray beam bolts onto left and right Jib attachment arms.
Because
the tightening is a true axial pull, the pin holes will come together to
exact alignment, facilitating pin insertion.
Users
of very early Climbing Cranes, tower cranes gaining height by climbing
from floor to floor in Hi-Rise buildings, may recognize the pulling
device.