Water to the fore!

Water to the fore!
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November 2014

 

Hydraulic components made by Rexroth enhance safety on offshore oil platforms. In case of a fire, they supply water to the sprinkler systems in a matter of seconds.

 

The fire-fighting exercise was an absolute success. The crew on the Brazilian oil platform gathered in the designated areas and within a few seconds the sprinklers poured water into every corner. In a real emergency, it is vital that all the procedures be correct and that all the technical equipment functions quickly and reliably. “This firefighting equipment must function under all circumstances. It must never fail!” emphasized Rogério Silva, manager for offshore technology at Bosch Rexroth in Brazil. The fire drill made it quite clear that everything runs without a hitch. The hydraulic extinguishing system immediately raised pressure from 30 to 350 bar. The sprinklers can spread 3.5 million liters of water over the platform – each and every hour.

Silva checks the CAD for the hydraulic unit.

Silva checks the CAD for the hydraulic unit.

 

Well thought out for high performance

Thirty meters beneath the platform but above water level, a sophisticated system ensures that everything works as planned. Bosch Rexroth worked it out together with Sulzer Brasil S.A., a pump manufacturer. The central element is an axial piston motor that drives an underwater, tandem-piston pump. It can, in the shortest conceivable time, deliver enormous quantities of seawater to the extinguishing system on the platform. Even if no fire alarm has sounded, the hydraulic motor runs continuously, at a slow 100 revolutions per minute. “This is important because, if there were longer downtimes, crabs and other marine animals would collect there,” Silva explains. If the motor were to start only when an alarm is signaled, those animals might interfere with the system. This is because, in case of a fire, the speed is raised almost instantly to as much as 1,600 rpm. A filter system ensures, in addition, that the oil is very clean.

Assembling the unit at the Pomerode plant in Brazil.

Assembling the unit at the Pomerode plant in Brazil.

 

“The ruggedness and reliability of the components and their low maintenance needs topped the list during development,” emphasizes Rogério Silva. “At the same time, the system was to be as small as possible – and that was a genuine challenge.” The project team used 3D models to find a solution and today everything meshes perfectly. “It was also important to work closely with the customer during the entire project. This made it possible to avoid errors,” says Rogério Silva.