Load Testing of MacGregor Deck Cranes

The container vessel is equipped with 3 deck cranes make MacGREGOR, type GL 4528-2S with a capacity of SWL 45t at 28m radius.

The vessel was scheduled for its 5 yearly cargo gear survey and overload testing is required with a proof load of 50T (i.e. proofload = SWL + 5T). ALATAS was called to carry out the annual lifting gear survey and to arrange 50T waterbag and conduct the overload test at Singapore Anchorage.

Our class certified crane inspector however noted a damaged hoisting rope on crane 1, that had to be changed prior to the load test. Alatas arranged it's rigging gang, rigging equipment & rope stand and carried out the wire rope change-out.

ALATAS then carried out the load test, including issuing the load test certificate and detailed load test protocol. Alatas scope of work for marine crane load testing and recertification includes the following, carried out by a multi-disciplined crane service engineer and class approved crane inspector:

  • Pre-inspection of crane structure, ropes, sheaves & blocks
  • Testing & adjusting of crane machinery & safeties, such as:
    • Limit switches
    • Electric, Electronic- & hydraulic overload protection equipment
    • Verifying Safe Load Indicators for rated & actual load indication, radius indication and correct alarm settings
  • Setting up the crane for overload testing, incl. by-passing of overload protection systems.
  • Conducting the load test as per ALATAS load test protocol & check-list
  • Recording of crane parameters, such as pressures for SWL and Proof Load
  • Re-setting all safeties to SWL to ensure the crane is fully overload protected.
  • Taking samples of the hydr. Oil to carry out oil analysis
  • Measuring axial clearance of slewing bearings (Rocking Test) and taking samples of the slewing bearing grease to carry out a ferrography grease analysis
  • If required: Issue ILO 152 Form 2 and endorse the cargo gear logbook
  • Issue a picture report with summary of findings & recommendations, c/w Load Test Certificate and Load Test Protocol

Following tests were carried out:

Nr. CraneSWL x RadiusProof Load
Crane 1:45T x 28M50.0 T (Waterbag)
Crane 2:45T x 28M50.0 T (Waterbag)
Crane 3:45T x 28M50.0 T (Waterbag)
Crane 4 (Aft)10T x 22M12.5 T (Pull Load Test)