McGregor Crane Jib Repair
Scope: Repair dented crane jib and re-certify to full
safe working load
In order to take the weight of the jib at the area to be repaired, we
started out by fabricating a structure to rest the jib on. We leveled
the containers with heavy duty I-beams and rested the jib on the crossbeams.
Due to the height of the repair area above the ship’s main deck,
we fabricated a working platform and placed it below the jib, leveled
and supported by adjacent cargo containers.
To prevent further structural damage during the repair, we welded a pipe
in between the jib’s longitudinal members for structural integrity.
We flame cut the damaged part of the jib external plating and accessed
the damaged internal supports.
Fabricated and installed several strong-backs, renewed the internal supports,
and fitted the new insert in position.
With hydraulic jacks we cold bended the deformed steel back to its original
shape. We left the strong backs in position to prevent any structural
damaged caused by the heat of the welding.
The welds were UT tested and approved by Classification Bureau NKK.
A 100% load test was conducted using water weights.
All repairs and tests were completed successfully and the crane was re-certified
and returned to service with a minimum of downtime.