Ice Management
An important part of ice management consists of keeping the
sailing routes near the drilling sites open. At times it is also
necessary to protect the installations themselves.
Our special Ice Breaking Supply Vessels
(IBSV) Arcticaborg and Antarcticaborg were designed
especially for the Caspian Sea. It is not possible to sail this Sea
with a conventional icebreaker.
- Shallow water: average of 3.5 metres near Caspian drilling
sites
- Ice: in the winter the Caspian Sea is covered with ice of up
to 90 cm thick
- Ice ridges: Are formed by drifting ice and can reach up to 10
metres high
Conventional icebreaking, with the bow, is only possible when
there is enough water under the keel. In limited water depths, such
as in the north of the Caspian Sea, the broken ice does not flow
away, but simply stays under the ship. Eventually, the ship gets
stuck on the ice.
Our IBSVs are able to remove ice and ice ridges in the area
surrounding the drilling sites. An ice ridge consist of many
different ice floes which in turn are formed by drifting ice. They
jut out up to 10 metres above the normal water level.
With Ice Protection Structures (IPS) we also influence the
formation of ice ridges at a strategic distance from the drilling
sites. These IPS are sunk and weighted down with ballast. The ice
drifts against the barrier and breaks up, and the ice forms a
natural barrier against further ice movement, which creates a
protected passage to the drilling site.
That is how we ensure that the
drilling site is provisioned during the winter periods and the
drilling operations can be continued.