END-TO-END TOWHEAD LOGISTICS

ONSHORE AND OFF, WE OVERCOME ROUTING CHALLENGES FOR SUBSEA INFRASTRUCTURE

Offshore infrastructure always starts its life onshore. That means clients need an end-to-end logistics plan for delivering it, and that means working with multi-modal transport. Osprey’s teams create a phased plan that overcomes all the challenges, onshore and off.

Premier Oil needed its new towheads delivered against a demanding 7-month schedule. Using our own equipment for heavy lifting, marine transport, and overland shipment, we collected and moved them all to one location for final assembly before taking them offshore.

PHASED APPROACH, COMMUNITY ENGAGEMENT

• These logistics were planned in phases. First, we held a HIRA meeting with our client, at which a marine warranty surveyor helped us identify potential high risks. We mitigated them all, got the project documentation finalised, and the end-to-end logistics were signed off by the client.
• Next, we collected the individual towheads and transported them to quayside for load out. This part of the move involved getting permits, organising road closures, rerouting local traffic and over-bridging a weak rail bridge.
• We used our LG1750 crane to load the towheads onto one of our own barges, secured them, and got approval from the marine warranty surveyor before shipping up to Wick. This involved getting support from assist tugs, linesmen and pilots – we take responsibility throughout.
• On arrival, we ballasted the barge to a pre-determined draught, so that we could put conventional trailers under the towheads and RORO them off during a rising tide. This was repeated several times to get all of the assets into the client’s holding area, ready for transportation to the installation site.
• Each move to site took approximately 5 hours, but moving through the town of Wick gave us more challenges. We arranged road closures with minimum disruption, removed walls, lowered the lampposts and temporarily removed other street furniture, too.
• We also engaged with the local Scout Group. We explained what we were doing, and they helped us with a letter drop informing local residents.
• Finally, we moved each towhead along onto a ‘track’ at the site, to cross around 7km of rough terrain. For the client, this meant a much shorter journey and fewer risks in load out. The towheads were then lowered onto stools, ready for jacking and skidding out to the carrier pipe.

JOINED-UP APPROACH ENSURES SMOOTH OPERATION

By getting involved early on, we could scope and propose a phased logistics plan that handled several different environments.

For our client, Premier Oil, each one of those environments presented a unique set of challenges for the high value assets involved. Osprey’s approach to multi-modal logistics overcame all those challenges, delivering on time and on budget.