16
4.3.3 Nut and Bolt Loosening Information
• Be aware that more torque is usually
required to loosen a fastener than to
tighten it.
• Rusted fasteners (humidity corrosion)
may require up to twice the torque
required for tightening.
• Fasteners that are corroded due to
contact with sea water or chemicals will
require up to two and a half times the
torque required for tightening.
• Heat corrosion requires up to three times
the torque required for tightening.
WARNING
Do not apply more than
75 percent of the wrench’s maximum
torque when loosening nuts or bolts.
Avoid making sudden start-stop
movements (“shock loading”). Failure to
observe these precautions may cause a
catastrophic failure of the wrench to
occur, and wrench components under
high tension could become dangerous
projectiles. Serious personal injury could
result.
4.3.4 Loosening a Nut or Bolt
(Fig. 16 and 17)
• Apply penetrating oil to the threads.
Allow the oil to soak.
• Position the tool on the nut or bolt
with the anti-clockwise (-) side facing
outwards, and the clockwise (+) side
facing the joint.
• Position the foot (17) of the reaction arm
(6) against a suitable reaction point (18).
The reaction point will counteract the
force caused by operating the tool.
• Start the pump.
• Operate pump until nut (bolt) is loose.
If the nut or bolt will be re-used, avoid
excess load when loosening.
WARNING
During loosening, a nut or
bolt may be subjected to stresses
beyond its material limits, which could
result in a permanent reduction of its
strength. This reduction could lead to
catastrophic failure of the nut, bolt or
joint if the fastener is reinstalled. If there
is any doubt as to whether the force used
during loosening has caused excessive
stress, the removed fastener(s) should be
discarded and replaced with new
fasteners of the proper specifications.
Fig.16
Fig.17
ENGLISH
