Reeling calculations

About the course

Detailing the engineering behind reel-lay installation, this is an advanced course that demystifies this complex field. Ideal for reeling companies and anyone involved in the design and installation of pipelines, this course explains the fundamentals of reel-lay.

The tutor will explain key design aspects such as the implications of cumulative plastic strain, ovalisation and weld defects using worked examples and exercises. You will receive guidance on codes and patents and review lessons learned from past successes and failures, developing your skills for installation projects.

Learning outcomes

  • Explain the principles and processes of pipeline fabrication and installation using reel-lay
  • Identify and assess the key design aspects of the reeling process while listing the key pitfalls
  • Calculate the required tensions and forces in the pipeline and on associated equipment during reeling, and also the limits for these forces to prevent failure
  • Explain how strain concentrations can form during the reeling process, the potential effects of these concentrations and the safeguards against them
  • Specify materials and qualification testing for pipe installed by reel-lay




4 Days

Study hours


Upcoming dates


Request for a quote to get a training date

Reeling calculations - course contents


Reel lay process

  • Reel-lay system configuration
  • Spooling
  • Installation
  • Lay down

Reeling history and current market

  • History and development of reeling
  • Reeling ships and companies around world

Case studies: failures and successes

  • Canapu pipe-in-pipe success
  • Åsgard field joint buckling failure
  • Foinaven twisting problem
  • Tambar stress cracking failure
  • Nile insulation success


Key technical aspects

  • Strain concentration
  • Material qualification
  • Weld defects
  • Ovalisation
  • Reeling forces
  • 13% chrome pipe
  • Clad pipe
  • Plastic-lined pipe

Codes and patents

  • Codes relating to reeling
  • Around the world
  • Patents related to reeling

Reeling forces

  • Force to reel-on
  • Stresses once reeled-on
  • Exercise
  • Elastic energy in reel
  • Force needed to straighten
  • Gripping force
  • Worked example
  • Exercise
  • Stationary versus traversing straightener


Strain-concentration effects

  • Stress-strain curves
  • Effect of strain on material properties
  • Plastic behaviour during reeling
  • Exercise
  • Geometric discontinuities
  • Material strength discontinuities
  • Lay process control methods
  • Strain concentrations at discontinuities
  • Exercise
  • Safeguards


  • Ovalisation and recovery
  • Collapse pressure and combined loading
  • Worked example
  • Exercise


  • Gauging and flooding
  • Hydrotesting
  • Dewatering, air and vacuum drying
  • Testing of valves and controls

Quality, safety, health and environment (QSHE)

  • Law
  • QA
  • HSE management
  • Risk assessment
  • Health
  • Safety
  • Environmental


  • Survey methods
  • Survey operations


Material and weld defects

  • Welding methods
  • Welding procedures
  • Inspection methods for welds
  • Defect assessment methods
  • Worked example – crack growth during reeling
  • Exercise – effect of load cycling on root crack weld fatigue life
  • DNV ECA methodology


  • Optimised reeled pipe design
  • Cost-effective reeling
  • Deep water pipeline and riser
  • SCR hybrid installation
  • Clad pipe qualification