Introduction
One of the most efficient
mooring systems in harsh environments is the turret system. This system can
be described as the ship being pinned to the seabed. The seabed part is a
fixed and static part while the attachment to the ship is free to rotate
around the anchor legs. The rotating
device can be attached to the hull in different ways and also in different
locations on the ship. This depends on variable factors like the design of
the ship, length, process requirements and accessibility. Due to this
variety in location of the turret systems, is it possible to distinguish
different types of turrets. The main types of turrets are the internal and
external turrets.
Turret and turret casing
As mentioned before the
system consists of a static part attached to the seabed. This part is
called the turret. The other part rotates and is placed inside the hull.
This part is called the turret casing. These two parts are joint by means of a main bearing.
Turntable
The turntable is a structural platform on top of the
turret that accommodates various units such as pig launchers/receivers,
chain tensioning winches, riser pull-in punches, electrical/control units,
leak skids etc.