ICON was engaged very early on and provided pre-rig award field layouts to confirm suitability that the selected rig was able to changeout HXT’s on two different wells from one pinned location. Based on rig capability and ICON’s proposed HXT running sequences, the Valaris 107 rig was selected, being a Keppel Fels Mod V Jack-up design.

Once the rig was selected, ICON was also involved in multiple scopes associated with preparing the Valaris 107 for the subsea work overs including:

• Rig positioning and field layout drawings to access both wells and subsequent sequence drawings for both workover operations;
• Installation of workclass ROV package on the starboard aft corner;
• Installation of bleed off package on the port aft corner;
• HXT lift studies and sequence drawings for running the HXT from the Jack-up whilst on critical path; and
• Set up and repurposing of conductor tension deck (CTD) for HXT handling and equipment laydown.

Early engagement at the rig selection stage allowed ICON to confirm the selected rig had adequate cantilever capacity and travel to changeout HXTs on both wells from one pinned location, thus avoiding multiple rig moves while in close proximity to subsea infrastructure. The above layout shows well proximity and rig position.

Subsea equipment deck and riser running  

ICON designed a solution to utilise the conductor tension deck as a staging area for subsea equipment prior to deployment. The existing CTD opening was infilled with a load rated deck to allow laydown of the HXT’s, TRT and Umbilicals with an access gangway to a separate working platform for running the HP riser. 

The infill deck installation also included a pod line winch, HXT and TRT inspection stands as well as a dedicated area for the IWOCS HPU and reeler as shown above.

ICON also developed engineered lift plans and handling studies for the HXTs, from lift off from vessel, handshaking, down to the Subsea equipment deck and deployment. The IWOCS package was deployed in parallel with the HP riser, with the sheave connected to padeyes and a CT winch designed and commissioned by ICON.