Belov Engenharia Ltda. to operate Robert Allan Ltd. designed Dive Support Vessels for Petrobras

March 26, 2020

A renewed wave of investments in the Brazilian offshore industry has appeared on the horizon kindling the demand for new highly specialized vessels such as a new Robert Allan Ltd. design of the RAlly family.

Underwater service providers play a major role in maintaining offshore assets, especially in deep water, by performing diving operations and ROV (Remotely Operated Vehicles) surveys.

In the plethora of Brazilian operators, a company stands out from the crowd, having performed work for the Brazilian state-run oil company Petrobras for several years: Belov Engenharia Ltda.

Understanding this new demand, and preparing for the tenders to come, Belov had decided to build (at their own fabrication facility in Salvador) and operate two new Dive Support Vessels (DSV), engaging Robert Allan Ltd. to prepare the Contract Design package of the vessel. Both vessels (Belov Amaralina and Belov Humaitá) have completed the construction and class commissioning and are currently performing client acceptance testing. Belov Engenharia Ltda. developed the detailed design, construction and commissioning of the Belov Amaralina in just over 18 months. This is an outstanding feat for a newly built shipyard, which includes the construction of a new floating dock.

These interesting new vessels are of the RAlly 4000’s Class design, fitted with Dynamic Positioning System (DP2), four diesel generators, three water jet propulsors and triple bow thrusters for redundancy. The propulsion system is diesel-electric to improve efficiency when operating in lower power DP modes. The vessel is certified as a Special Diving Support vessel suitable for Unrestricted Navigation by RINA.

The RAlly 4000 was designed by Robert Allan Ltd. to be fitted with an ROV LARS (Launch and Recovery System), an aft mounted A-Frame to operate the diving bell, a decompression chamber to support the divers, and more spacious crew quarters. All of this is incorporated within a gross tonnage under 500 GRT.

Waterjets are used to ensure diver safety. Because waterjets are typically used on higher speed vessels, extensive self-propelled CFD analysis (including waterjet tunnel flow) was performed in-house by Robert Allan Ltd. to verify resistance and thrust at the slower speeds that this design will operate at when on station. The new RAlly 4000 SDSV has the following particulars:

  • Length overall: 40.50 m
  • Beam: 10.98 m
  • Speed: 12+ knots
  • Crew: 38 (including divers)

We wish fair winds and calm seas to the Belov Amaralina and the Belov Humaitá.

For more information on the RAlly Series, please contact