DROMEC Winches develops three-stage pull-in system

Boskalis Subsea Cables is responsible for the pull-in operation of high voltage cables at a offshore substation. DROMEC Winches has developed a pull-in system where the cables are pulled in from the ship in the substation under Constant Tension. Unique to this pull-in system is the extreme ratio of 20 tons of pulling force combined with a system weight of 1450 kg.

Pull-in System

DROMEC Winches previously built a series of pull-in systems for Boskalis with pulling forces ranging from 8 to 10 tons. The good collaboration during these projects provided the boost for this new development. The operation for this pull-in system is exactly the same as for the previously delivered systems. The system may look complex, but it is incredibly user-friendly; at a glance, the operator can see what they are doing on the touch screen. DROMEC uses the same software platform for all pull-in systems. The dimensions are also compact so that the system can be transported through a door.

Three-stage

This pull-in system has an electric drive with Constant Tension. In case of excessive pulling force, the system automatically releases. It has two capstans and a puller, each with its own brake motor to ensure triple safety. This ensures compliance with LOLER and PUWER guidelines. The three subsystems ensure that the force is built up step by step. The lower main capstan generates a pulling force of 20 tons, the intermediate head generates 2.5 tons, and the puller has a pulling force of 150 kg. This is how the system operates autonomously.

Cees Drost, CEO of DROMEC:
‘Boskalis is a great company to work for. With this innovative expansion, the company can safely pull in heavy high voltage cables.’

Knots and bridles

A knot or bridle? In this pull-in system, DROMEC Winches has developed a puller with a special spring applied so that even those obstacles pose no problem when pulling in the high voltage cables.