Function
Internal platforms are used to support equipment housed in the transition piece and to provide personnel access for installation and maintenance purposes. They are also used to seal the upper reaches of the transition piece.
Who supplies them
These are usually supplied by the supplier of transition pieces [B.2.3].
In practice, the steelwork for the internal platforms may be subcontracted to a smaller steelwork supplier.
Key facts
The lower platform provides an airtight seal between the monopile and the TP. This is because hazardous gases can accumulate inside the lower part of the monopile from the corrosion protection system.
The upper platform provides access to the bolted connection between the transition piece and the tower base. It may also include the cable hang-off, this may alternatively be included on an intermediate platform.
Further platforms may be included:
- To provide access to the bolted connection between the monopile and transition piece, or
- To support the turbine transformer, switchgear and a personnel refuge, although these can alternatively be located in the lower reaches of the turbine tower.
What’s in it
- Lightweight structural steel frame and decking