During MBM’s ‘Sand Carrier – Open Barge’ conversion project, the client aimed to convert a vessel from one service sector to another by implementing an innovative design of a steel structure that covers its open hold, which measures 103m x 21m. The structure would allow transport of project cargo using approximately 600t of steel, which may be removed in the future for the vessel to return to its previous operational service sector with minimum re-work (for example, leave all machinery operational and in place).

MBM designed, analysed and presented the following solution: a high-tensile steel closed project cargo deck, made of deep transversals and shallow longitudinals, without vertical supports. The new ‘Project Cargo Transport Deck Area’ was increased at MBM suggestion to cover an area of 103m x 26m to include coverage over the port and starboard passageway.

MBM made this suggestion after the first vessel survey whilst on the project as the vision is to assist the client with the optimum solution. This solution would provide an operational opportunity to increase the potential return of investment (+ROI) by utilising a RO-RO method from port / starboard loading with an SPMT option.

The final ‘Project Deck’ has a class-certified deck strength of 10t/m². The new structure is in correlation with the existing vessel frame spacing of approximately 1,500mm to harmonise and reduce structural stress and bending. MBM final solution has 5m x 103m = 515m² more deck area than requested for only an extra 100t of steel, with the overall weight of approximately 700t of steel not including paint, weld or additional lashing points.

The deliverables from MBM included:

  • New GA
  • New capacity plan
  • New stability booklet, with added steel, and future project cargo as loading conditions
  • Creation of the missing hull linesplans
  • Midship steel section drawing and calculations
  • Longitudinal strength and local strength calculations
  • Steel manufacture drawings
  • Classification approval

To make an enquiry for your vessel conversion, upcoming / ongoing ballast water treatment system implementation, fuel system conversion, vessel lengthening, scrubber, carousel cable deck layout for OSV, crane capacity upgrades, void tank conversions, bulbous bow fuel efficiency improvements, or any other conversion, please contact MBM-Consultancy.