Subsea pipelines carry oil, gas and multiphase fluids from wells to platforms and shore, and they must be designed for internal flow, external loads, installation and decades of service. This course covers the design, routing, structural behaviour, installation and construction of subsea marine pipelines for oil, gas and multiphase service. It progresses from internal flow design, including single-phase hydraulics, heat transfer, multiphase flow, slug catchers and flow assurance, through thermal insulation and structural design for pressure containment, collapse and buckling, to route selection, on-bottom stability, shore approaches and burial. It then covers pipelay methods and installation support engineering, pipe manufacturing, materials and coatings, offshore welding, non-destructive testing and safety and risk management, using real project examples to show how design decisions are made in practice.
Course at a glance: Duration 20 hours · Self-paced online · Level: Intermediate · 13 sections, 52 lessons, a 233-page downloadable course book
What you will learn
- Explain why marine pipelines matter, how they evolved and the main system types.
- Size pipelines using single-phase liquid and gas hydraulics, including heat transfer and cooldown.
- Describe multiphase flow regimes, liquid hold-up, slug catchers and liquid surges.
- Explain flow assurance challenges such as hydrates, wax, asphaltenes, emulsions and slugging.
- Apply hoop stress, collapse, propagation and buckling concepts to pipeline structural design.
- Evaluate route selection, on-bottom stability, shore approaches and trenching and burial.
- Compare pipelay methods and outline pipe manufacturing, materials, coatings, welding and NDT.
Inside the course: a high-level summary, section by section.
Marine pipeline foundations
The course opens with why marine pipelines matter: they are the most economical way to move large volumes of oil and gas over long distances, linking subsea wells, platforms, floating production units and onshore terminals. A short history shows how pipelines moved into deeper water, helped by developments such as dynamically positioned lay vessels, which removed the practical depth limit of anchor-handled laying. System types range from large-diameter, long-distance trunk lines to infield flowlines and smaller piggy-back lines. The materials and context lesson sets out the scope of the course.
Single-phase hydraulics
Hydraulic sizing begins with inputs such as flow rate, fluid properties, inlet and outlet pressures, elevation profile and temperature. Liquid flow pressure loss is calculated using friction factors and pipe roughness, while gas flow requires consideration of compressibility and the need for compression along the line. Heat transfer and cooldown analysis predicts how fluid temperature changes along the pipeline and during shutdown, which strongly affects flow assurance.
Multiphase flow
Many pipelines carry mixtures of oil, gas and water directly from wells, avoiding offshore processing. The course explains why multiphase transport is used, then describes liquid hold-up and flow regimes, such as stratified, slug, annular and dispersed flow, which depend on flow rates, pipe inclination and fluid properties. Validation and design confidence discuss how multiphase models are checked against field data. Real project examples illustrate the challenges of long multiphase tie-backs and how design teams approached them.
Slug catchers and surges
At the receiving end of a multiphase line, slug catchers separate gas and liquid and absorb liquid surges. The course explains the role and layout of slug catchers, sources of liquid surges, such as terrain slugging, pigging and flow rate changes, and the mechanical design and buildability of slug catcher systems.
Flow assurance
Flow assurance ensures that fluids keep flowing throughout field life. The framework covers hydrates, ice-like solids that form at high pressure and low temperature and can block lines, and their prevention by insulation, heating or chemical inhibition. Wax deposition, asphaltenes and emulsions are also explained, along with slugging and its effect on operability.
Thermal design
Heat retention and cooldown time are key flow assurance parameters. Insulation concepts, including wet insulation coatings, pipe-in-pipe systems and burial, are compared, and thermal design trade-offs balance insulation performance, cost, installation and structural effects.
Structural design
Hoop stress from internal pressure sets the minimum wall thickness, and design codes provide formulations for pressure containment, collapse under external pressure and combined loading. The course introduces the code-based approach used for offshore pipelines. Local collapse and propagating buckles, which can travel along a pipeline in deep water, are explained, along with buckle arrestors. Upheaval buckling of buried lines and lateral buckling of surface-laid lines result from thermal expansion and pressure, and their control is discussed.
Route selection and stability
Route selection criteria include seabed bathymetry, geohazards, existing infrastructure, environmental sensitivities and fishing activity. On-bottom stability ensures that waves and currents do not move the pipeline, using concrete weight coating or burial. Shore approaches present special challenges in the surf zone, and trenching and burial protect pipelines from fishing gear, anchors and dropped objects.
Installation
The pipelay process overview introduces the main methods. S-lay suits shallow to moderate depths, with the pipe leaving the vessel horizontally over a stinger. J-lay suits deeper water, with the pipe leaving nearly vertically. Reel-lay spools pre-welded pipe onto a large reel for fast installation, and tow methods transport long pipe strings. Installation support engineering covers lay analyses, tensioners, abandonment and recovery and seabed intervention.
Manufacturing, materials and coatings
Pipe manufacturing routes, such as seamless and welded pipe, are explained along with pipeline materials selection, including carbon steel, corrosion-resistant alloys and clad pipe. Coating systems provide corrosion protection, thermal insulation and weight.
Welding, NDT and safety
Offshore welding processes, from manual to automated methods, and non-destructive testing methods such as automated ultrasonic testing and radiography are reviewed. Safety and risk management close the course, covering hazards during construction and operation and the management of pipeline integrity.
Why this matters in practice
Pipelines are long-lived, expensive assets whose failure can cause major environmental and economic damage. Engineers who understand the full chain from hydraulics and flow assurance to structural design, routing and installation can contribute to safer, more economical projects and communicate effectively across disciplines. Many pipeline problems arise at the interfaces, for example when a flow assurance requirement for insulation changes the on-bottom stability or installation tension, or when route choices affect buckling behaviour. Understanding these interactions is what allows engineers to find balanced, buildable solutions.
Key takeaways
You leave able to size pipelines hydraulically, explain multiphase flow and flow assurance, design for pressure, collapse and buckling, select routes and ensure stability, and outline pipelay, manufacturing, coating, welding and inspection practices.
How you study
The course is delivered fully online and is self-paced, so you can fit roughly 20 hours of study around professional commitments. Lessons combine clear explanation with examples, diagrams and short interactive checks, and the main sections end with graded quizzes (11 in total) so you can confirm you can apply each method before moving on. A 233-page course book can be downloaded and printed for offline reading and later reference.
Course contents
- Marine Pipeline Foundations: Why Marine Pipelines Matter; History and System Types; Materials and Course Context
- Single-Phase Hydraulics: Hydraulic Sizing Inputs; Liquid Flow Pressure Loss; Gas Flow and Compression; Heat Transfer and Cooldown
- Multiphase Flow Fundamentals: Why Multiphase Transport; Hold-Up and Flow Regimes; Validation and Design Confidence; Sabah and Ormen Lange
- Slug Catchers and Surges: Slugcatcher Role and Layout; Sources of Liquid Surges; Mechanical Design and Buildability
- Flow Assurance Risks: Flow Assurance Framework; Hydrates and Inhibition; Wax, Asphaltenes, and Emulsions; Slugging and Operability
- Thermal Management: Heat Retention and Cooldown; Insulation Concepts; Thermal Design Trade-Offs
- Structural Pipeline Design: Hoop Stress and Wall Thickness; DNV Design Formulations; Collapse and Propagation; Upheaval and Lateral Buckling
- Routing, Stability, Trenching: Route Selection Criteria; On-Bottom Stability; Shore Approaches; Trenching and Burial
- Pipeline Installation Engineering: Pipelay Process Overview; S-Lay and J-Lay; Reel-Lay and Tow Methods; Installation Support Engineering
- Materials and Coatings: Pipe Manufacturing Routes; Pipeline Materials Selection; Coating Systems
- Welding, NDT, and Safety: Offshore Welding Processes; NDT Methods; Safety and Risk Management
- Summary: Key Takeaways
Who this course is for
This intermediate course is for engineering graduates and practising engineers in subsea, pipeline, offshore and process engineering who want a structured refresher across marine pipeline design and construction. The course assumes an engineering degree or equivalent experience.
Frequently asked questions
How long does Marine Pipelines take?
The course is designed for about 20 hours of study. It is self-paced and fully online, so you can spread it over a few weeks or complete it more quickly.
What is covered?
The course is organised into 13 sections with 52 lessons, moving from foundations to applied methods, as summarised above.
Is there material to keep after the course?
Yes. A downloadable 233-page course book accompanies the lessons for offline reading and later reference.
How is progress checked?
Each main section closes with a graded quiz (11 in total). The quizzes test understanding of the concepts and methods explained in the lessons rather than memorisation, and you can review the relevant lessons before attempting them.
Can I record this study for my own professional development?
Yes. The course notebook includes a self-assessment of the course objectives before and after study, a reflection page and a learning log, which you can use to keep your own record of professional development.
Level: Intermediate
Duration: 20 hours
Related courses: D01 – Offshore Engineering Fundamentals; D11 – Arctic Offshore Engineering Part 1; C05 – Fluid Mechanics: Pipe Flow & Pressure Loss; D05 – Offshore Hydromechanics
Enrol
Study at your own pace and work through the full course material, worked examples and section quizzes. Enrol in D09 – Marine Pipelines →
Recent Comments