Deepwater Installation

Evolving our marine assets as technology pushes us deeper.

Deepwater exploration is costly, risky and time consuming. McDermott offers sophisticated technology, proven equipment and methods, reliable and safe performance to ensure successful hydrocarbon extraction.

McDermott’s in-house marine engineers work closely with our fabrication and engineering departments, as well as our joint venture companies, technology companies, academic institutes and industry bodies to deliver client-orientated, quality engineering and construction for deepwater solutions. We have the assets, skills, meticulous procedures and decades of record-setting experience to ensure success:

20-plus years of proven subsea engineering experience designing field architecture
Fabrication facilities to construct quad joints, tendons, manifolds, PLETs, jumpers, flying leads, PLEMs, etc.
Track record installing platform hulls and integrating topsides for TLPs, Spars, Semis and FPSOs
Reliable installation vessels to install flowlines, SCRs, in-line structures, PLEMS, manifolds and other subsea hardware
Superior welding technology and high-quality execution
Experienced project management, cost control and scheduling expertise to manage risk
Worldwide EPCI resources and engineering experts across all fields of project development
Decades of innovating to overcome technical challenges
Comprehensive modeling for weather and meteocean effects to ensure installation within the required weather window
Strategic partnerships provide spool base access on a project basis

Heavy Lift & Integration

Our primary deepwater heavy lifting vessels are DB50 and DB30.

Our single lifting capacity for upending substructures, such as Spar hulls, and lifting topsides for floating production platforms, is 4,400 tons. For structures above this weight, we offer economically viable alternatives such as dual lifts and float overs for topsides to hull integration up to 22,000-tons, in both sheltered waters and exposed offshore sites. Our heavy lift vessels perform deepwater lowering and pipelay, making them versatile assets for any deepwater project.

Deepwater Lowering Systems

Our primary deepwater lowering vessels are DB50, NO102 and LV105 (available 2012).

Our vessels are equipped with hydraulic or electric winches and active heave / motion compensation and position-monitoring devices, essential for load control and orientation accuracy. We also focus on rigorous maintenance, to ensure equipment reliability. Our experience covers manifolds, jumpers, flying leads, PLETs, PLEMs etc.

Lifting and lowering technology, tension capacities, load control and positioning are significant factors we address as we undertake rigorous analysis and simulation of lift / lowering dynamics prior to deepwater installation to address weight-related issues of equipment to be lowered to the seafloor.

Deepwater Pipelay

Our fleet of deepwater installation vessels offers:

Flex-Lay - primary Flex-Lay vessels are NO102 and LV105. Read More >

McDermott offers engineering, installation and retrieval of flexible product through Flex-Lay. Pipe is typically spooled from a reel, bent over a chute and guided into tensioners and onto the seabed. Flexible pipelines are less sensitive to fatigue and this efficient installation method is suitable for both shallow and deep water, offering high production rates for umbilicials, cable and flexible pipe, etc.

Reel-Lay - primary Reel-Lay vessel is LV105. Read More >

McDermott offers engineering and reeled installation of rigid pipe, suitable for fields with highly corrosive hydrocarbons or demanding flow assurance requirements, such as high-performance insulated flowlines. Reel-Lay offers economical installation for small-diameter pipes (up to 16 inches) of limited length. In a controlled onshore environment, welding and testing pipe joints, coating pipe, or preparing pipe-in-pipe is carried out before product is spooled onto a reel. During installation, pipe is unspooled, straightened and overboarded as the vessel moves forward. Strategic partnerships provide spool base access on a project basis. Suitable for both shallow and ultra-deepwater installation, reel-Lay offers high production rates for installation of Steel Catenary Risers (SCRs), however, pipe diameters are restricted by reel size.

J-Lay - primary J-Lay vessel is DB50. Read More >

McDermott offers engineering and J-Lay installation of deepwater, rigid pipelines, including fatigue sensitive SCRs, large diameter and concrete coated pipelines. We have laid pipe-in-pipe and inline structures, including PLETs and PLEMS, in water depths up to 4,400 feet, meeting stringent welding criteria. Laying pipe at near-vertical angles reduces touchdown distance allowing pipelines to be laid to exacting routes, safely negotiating sea-floor hazards and complex in-field lines, and precisely locating lines over preinstalled crossings. J-Lay minimizes on-bottom tensions, reducing pipeline spans in irregular sea-floor topography and permitting installation of tighter curves. Although not as fast as reeling, J-Lay is a competitive installation method when deepwater pipelines are heavy or short, especially when combining SCR installation with heavy lift work, saving mobilization of multiple vessels.

Deepwater S-Lay - primary deepwater S-Lay vessels are DB16 and DB30 (after planned upgrades). Read More >

McDermott offers engineering and S-Lay installation, a fast and economical method of deepwater pipeline, SCR and in-line structure installation. Deepwater S-Lay requires a high capacity tension and A&R system as well as a long rigid stinger. Installing in a near vertical stinger departure angle limits the over-bend strains and limits tension requirements, which in turn facilitates positioning on uneven seabed areas to reduce free-spans and minimizes structural rotation. Heavy pipelines, such as pipe-in-pipe systems and water-filled pipelines, as well as pipe end manifolds and large in-line structures such as “wye”, “tee” and valve assemblies can be installed reliably and safely by S-Lay.

Our experience covers installation of pipelines incorporating wet-insulation, FBE or CRA coated (mechanical or metallurgical bonded) and pipe-in-pipe, as well as first-end and second-end PLETs and PLEMs and in-line sleds, SCR’s, free-standing risers, umbilicals, etc.

McDermott engineers and technical experts, design innovative pipe- and product-lay solutions, to meet stringent welding criteria for flexible and rigid-reeled pipes, umbilicals and power and control cables, as well as pipeline abandonment and recovery. Challenges arise from complexities such as proportional weight increases of riser steel with water depth that significantly affect material costs, and buoyancy or tensioning systems for deepwater pipelay. Surface production facilities are subject to technical issues such as payload limitations, and installation vessels are subject to tension limits.

Mooring System Deployment

Appropriate analysis tools and installation vessels enable high technical performance for reliable, cost-effective moorings. Rigorous planning and careful management of design and installation interfaces is imperative.

Our expertise covers conventional sheathed wire or polyester moorings and their foundations, employing either driven or suction anchors / piles, and top and bottom chains for Spars, Semi-submersible and ship-shape floating facilities. Our tendon fabrication facility and installation resources support Tension Leg Platform tendon systems, including associated piled or gravity foundations.

Before designs are finalized, we physically model critical metocean analysis through wind tunnel and wave basin tests, to address mooring strength, tension, fatigue and installation tolerance, from the foundation anchor to mooring points above surface. To ensure long-term integrity, we take extreme care to ensure zero or minimum twist in the mooring system during pre-installation or final hook-up. Our installation vessels employ low-torque pull-in wire, a second line for balancing torque, and an in-line swivel during pull-in to ensure tension accuracy during offshore hook-up.