Positive Operational LL with PGNiG

Copernicus (6608/1-1 S) – Rig move

What happened:

All tubulars were backloaded from the rig and mud and bulk tanks emptied. The rig was deballasted to transit draft( cross bracing clear of the sea surface ). The rig move was performed at transit draft and an average move speed of 6knts achieved.

What was planned:

Historical rig moves for DSY have been performed at operational draft with average move speeds of between 2.5 and 3 knts. Due to the long mobilisation distance to the Copernicus well it was planned to move the rig at a transit draft.

What was learned:

During the move there was excess thruster capacity which would allow higher transit speeds to be achieved however there is a risk of wave slamming on the fairleads.

What actions are required:

Evaluate whether wave slamming of fairleads at speeds greater than 6 knts is an issue and if so determine whether fairleads can be secured to prevent damage at higher speeds.