Decommissioning involves the safe plugging of the production wells and disposal of the equipment used in offshore oil production. Decommissioning is a rapidly developing market sector in the petroleum business, with major potential and major risks.  With the detailed knowledge regarding load transfer and mating operations, Semar has the necessary competence and experience to reverse the process and to carry out the planning, engineering, and supervision of the decommissioning of offshore platforms. Semar has been involved in a number of decommissioning projects.



›  AF Decom Offshore – L7 platforms removal – 2022-2023

›  Equinor – Veslefrikk B decommissioning – 2022-2022

›  AF Decom Offshore – FPSO Curlew Decommissioning, Brent Bravo, EKOF, jacket decommissioning – 2022-2023

›  DOF – YME leg removal – 2015-2017

›  AF Decom – H7 Platform removal (3rd party verification) – 2014

›  AF Decom – Statfjord C SPM loading buoy removal – 2011

›  Sevan – Decommissioning of Sevan Voyageur – 2010

›  AMC – Frigg Cessation – 2004-2008

›  AMC – Maureen GBS decommissioning – 2000-2003

›  Conoco – Feasibility of decommissioning of Kotter Logger platforms (5500t) – 1998

Areas of competence

›  Hydrostatic and hydrodynamic analyses

›  Structural integrity verification of decommissioned structure

›  Structural design of grillages and removal aids

›  Marine operations

SFC SPM Buoy Removal

SFC SPM Buoy Removal

SFC SPM Buoy Removal

Scope of work summary

›  Feasibility study (hydrostatic)

›  Stability study of the buoy during towing and for laydown sequence

›  Simplified stability test and structure measurements

›  Marine operation method development with AFDO

›  Tilting of SPM Buoy

›  Buoy float-over on barge

›  Offloading of barge to the quay side

›  Evaluate the structural strength (non-linear static and non-linear buckling) of the buoy

›  Design of installation aids (lifting beam and transport grillage)

›  On-site assistance

Key data

Client: AF Decom Offshore

Operator: Statoil

Project duration: 2011

Project characteristics: 181m high buoy / 8.5m diameter, 8000t including initial ballast