Offshore Met Mast RemovalRemoving Lattice Tower Section of Met Mast at Scroby Sands Wind Farm
Scroby Sands Offshore Wind Farm
Offshore Maintenance Specialists
Scroby Sands is an offshore wind farm located 2.5km off the Norfolk coast. Owned and operated by E.ON, the wind farm consists of 30 turbines and a meteorological mast fitted with a 40 metre lattice structure mounted on a 10 metre monopile, this lies to the north of the wind farm.
In 2015 E.ON wanted the lattice tower structure of the Met Mast removed and awarded a tender to Abfad. Having worked at Scroby Sands Wind Farm several times, both on the turbines and on the met mast itself, Abfad already had extensive experience of working at the wind farm, combined with over 20 years of offshore and onshore rope access experience, Abfad were the ideal candidate for the job.
The lattice tower is constructed in two distinct sections with the upper part making up approximately 40% of the tower, and consists of both flanged and bolted vertical sections with welded diagonal tubular bars. The lower section of the lattice tower is made up of both vertical and diagonal struts which are fully bolted. There were also redundant anemometry devices on the top of the mast, which had been disconnected from all power supplies.
The lattice tower needed to be removed in manageable sections, along with any instrumentation, Abfad used rope access techniques to rig up a pulley system which would safely and securely lower the cut steel sections onto the walkway of the mast, and from the walkway onto the service vessel, to be transported away and disposed of by E.ON.
Work consisted of:
1. Accessing the lattice section of the mast using rope access.
2. Removing all instrumentation devices still on the lattice tower.
3. Cutting down the lattice tower in manageable sections using industry standard cutting tools.
4. Lowering the cut steel sections and instrumentation onto the mast walkway by use of a rope access pulley system set up by Abfad.
5. Lowering the cut steel sections from the walkway onto a service vessel, again using a rope access pulley system set up by Abfad.
6. All steel once on service vessel to be transported away and disposed of by E.ON.