The Problem

Subsea 7’s Seven Waves pipeline vessel needed a control system for a spread of 10 electrically driven deck winches.

The Solution

Finesse was able to design and build the control system for Subsea 7 in time. The contract was supplied ahead of schedule and hardware was being commissioned in March 2013.

The system consisted of 8 drive panels holding Siemens S120 Drives for 10 winches ranging from 5Te to 40Te and a programmable logic controller (PLC) panel, incorporating an S7-400 FH dual-redundant safety PLC and an Human-machine interface (HMI) with a further 10 Local Control Panels containing remote IO networked over dual-redundant Profibus for local control of each winch on deck. Additionally, a Cavotec Walkabout Box (WAB) wireless system was incorporated allowing winch operation from various vantage points.

The Result

Based on the quality of our manufacturing and commissioning, Finesse were subsequently awarded a further three contracts to outfit the remaining Subsea 7 flagship pipelay vessels the Seven Rio, Seven Sun and Seven Cruzeiro.

We also provided additional hardware in the form of a drive panel and control system to control the on-board 15Te Overbender Track Tensioner on all 4 vessels. The system employs an S7-300FH PLC which controls the hydraulic system to provide the required ‘squeeze’ on the product and a Siemens S120 drive system which provides track movement and control. The Tensioner is controlled via a local control panel mounted on the tensioner or again wirelessly via a Cavotec WAB system.

Key Summary

• Design and build of control system for 10 electrically-driven deck winches on Subsea 7’s latest pipeline vessel at the time, the Seven Waves.

• 8 drive panels made holding drives for 10 winches.

• Cavotec Walkabout Box (WAB) wireless system incorporated to allow winch operation from various vantage points.

• Commissioned in 2012 for delivery in the first half of 2013.

• Further 10 local control panels for individual control of each winch on deck produced.

• Resulted with three more contracts to outfit remaining Subsea 7 pipeline vessels the Seven Rio, Seven Sun and Seven Cruzeiro.