DROMEC Winches develops winch systems

Kooiman Marine Group is an independent group of multi-disciplinary shipbuilders in the maritime sector. On behalf of Kooiman Marine Group, DROMEC Winches has developed specialized winch systems for the dredgers Maas and Mursy operated by Van Oord.

Active heave

On both sides of the dredgers, there are 25-meter-long injection pipes used to dislodge the seabed with water jets, allowing it to be carried away by the water’s flow. The pipes are lowered into the water at an angle using the winch system. The winches are equipped with active heave, which ensures that the pipe remains at the same height above the seabed, compensating for wave motion. Both the Maas and the Mursy are equipped with two winches.

Absolute encoder

The electric hoist winches each have a 110 kWh electric motor. The working load for lowering the pipes is 30 tons, with a peak load of up to 40 tons. The holding force of the winch system is 45 tons. In the event of a cable breakage, the ship can pull the winch up to the waterline and proceed to repair. What makes this system unique is the interconnection of the winches through an absolute encoder that records the motor positions. This synchronization allows the pipes to be lifted in parallel. When combined with active heave, this means that the system is constantly in motion. The active heave capacity is 20 tons, with a wave height of 400 mm amplitude within 7 seconds.

Jan Willem, engineer: “The control of the winch system is truly exceptional for these Van Oord vessels. We have had a positive collaboration with Kooiman Marine Group, with clear agreements in place. They entrusted us with the development of this system, and as DROMEC Winches, we have delivered on our promises. It’s satisfying to know that we are now building a series of 4 winches for 2 new vessels once again.”