The slewing bearing on the Stbd side Davit crane had failed. The provision crane, type Kyoritsu Kikai, SWL 0.9T x 6.6M was out of order for more than 2 years, as it was not possible to arrange a qualified crane service company that could arrange a crane bearing change-out on anchorage, and without the need for a shore based crane.

ALATAS proposal and solution was to lift-up the crane by means of a specially constructed and modular A-frame, that could be assembled on board without lifting aid.

Following work was carried out:

1. Assembled the A- Frame and shifted to STBD side from port side of vessel.
2. Placed A-Frame on top of crane and erected the staging around STBD crane pedestal.
3. Secured the crane by chain blocks (No crew available to assist).
4. Removed slewing bearing outer and inner bolts and nuts.
5. Removed the electrical cables from junction box 1 to slewing column.
6. Removed slewing gear box foundation bolts and slewing gear box.
7. Brought down damaged slewing bearing.
8. Cleaning bearing landing flanges by power brushing, on slewing column and on base column flange surfaces.
9. Applied new EP 2 grease to the new slewing bearing before installation.
10. Installed new slewing bearing (Customer supplied) tighten all inner and outer slewing bolts (415 Nm) by using Alatas supplied torque wrench.
11. Fixed back slewing gear box and electrical cables.
12. Tested operation, slewing lift/right limits, hoist up anti two block limit, witnessed by Class NK surveyor, Superintendent, Captain & Chief Engineer.
13. Measured new slewing bearing deflection with and without load.
14. Conducted load test and overload test (SWL 0.9 ton and proof load of 1.125 ton), as witness by superintendent and Chief Officer.
15. Dismantled A – Frame, Scaffolding, tools and materials.
16. Arranged all materials to be ready for offloading.

After being 2 years out of operation, the crane has been fully commissioned and re-certified by ALATAS and is ready again for unrestricted cargo operation.

ALATAS issued a full service report, including bearing axial clearance measuring protocol, crane load test protocol & crane certificate. ILO152 Form 2 is available as well.