Marginal Column

Barge Master: Lifting loads safely even in extreme waves


Boy Biemans / Sales Engineer Offshore Projects
Arnold Krielen / Sales Manager Offshore Projects
Bosch Rexroth Netherlands

Crane operations at open sea or offshore is always a critical operation. Due to the waves, an offshore crane tip, including its load, can swing several meters depending on the crane’s height. The sea conditions can limit the window of safe operation for offshore contractors.

Barge Master, a young Dutch company, was looking for a solution to this problem. The two founders, with many years of offshore experience, were driven by an idea: Why not develop and build a system that compensates the motions between the ship's hull and the crane? This would allow work vessels to operate cranes safely, even in high waves. The challenge: No such system had been created yet.

To develop this solution, Barge Master needed the right engineering and technology partner — and Bosch Rexroth met the required profile. Bosch Rexroth offered the unique combination of experience with the development of motion technologies and with equipping maritime and offshore applications. Plus, Bosch Rexroth also has proven technology engineered to move loads of several hundred tons—the weight of a crane with its load—in a safe, yet highly dynamic manner.

“We have already developed complex motion technologies for other applications”, said Boy Biemans, Sales Engineer Offshore Projects for Bosch Rexroth in the Netherlands. “Moreover, we have been a project partner for the shipbuilding and offshore industries for decades. We know their requirements and the environmental conditions very well.”

As engineering partner of Barge Master, Bosch Rexroth took full project responsibility for engineering, planning and implementing the motion compensation drive and control solution. Sensors measure the vessel motions and the control system calculates the required counter motions. This action requires the strength of hydraulics: Only with hydraulic cylinders is it practical to produce these counter motions for a load of several hundred tons.

This compensation is accomplished in three degrees of freedom, called in shorthand 3DOF; the three degrees are heave, pitch and roll. “We are talking here about very complex kinematics. The smallest change in the mechanical geometry has enormous impact on the drive and control system”, Biemans explained.

The most important customer requirement: “First and foremost, for such a project, we need to eliminate all uncertainties before we commission the system”, said Arnold Krielen, Sales Manager Offshore Projects for Bosch Rexroth and Biemans’ partner on the project.

Krielen describes the process: Rexroth specialists investigate all kind of possible operation conditions by means of simulation programs, specifically designed by Bosch Rexroth. These simulations illustrate the specifics of the fluid technology. “This way, we can predict precisely how the system will react and the hydraulic components behave”, he said.

Next, the system was built, tested and certified at the Boxtel, Netherlands plant. Only when the specialists were sure that everything was working exactly as intended was the first wave compensation platform installed and commissioned on a ship. The first test run demonstrated the effectiveness of this approach: Thanks to the 3DOF motion compensation, the crane lifts loads safely and deposits them precisely even in significant waves up to three meters high.

For Barge Master, an innovative idea became their business foundation. Now the company markets a variety of solutions equipped with drive and control systems by Bosch Rexroth. Motion compensation systems can be used for many more applications in the offshore market, and have the potential to significantly increase the operational window and reduce construction costs for offshore wind parks and other installations.

Details on Barge Master and videos of the systems in operation: