Lateral Buckling and
Pipeline Walking

A New Requirement in Pipeline Engineering
The move to deep water and higher temperatures and pressures in recent years has introduced lateral buckling and walking as new problems in the pipeline design process. Where practical and economic considerations prevent burial of pipelines, the potential to 'snake' and 'walk' is often unavoidable. Advanced design and analysis methods, often coupled with special construction measures, are then needed to ensure a safe and reliable system containing 'engineered' lateral buckles.

KW have been at the forefront of developments in this specialist field, with a substantial track record of lateral buckling and walking studies for leading international contractors and operators worldwide. The mitigation measures required to control walking and lateral buckling can be very costly. KW has wide experience in the design of fully integrated solutions, designed to guarantee pipeline integrity for minimum overall cost.

Specialist Services
KW can deploy a wide range of analysis tools and techniques, suitable for preliminary concept studies, tender design/validation, FEED and detailed design. Typical tasks include:
• Review of soil parameters and estimate of pipe-soil interaction forces. Specification of additional in-situ and laboratory soil tests.
• Rapid screening assessment using analytical methods (Hobbs, Taylor and Gan)
• Advanced non-linear FEA of buckle initiation and post-bukling response, including non-linear pipe-soil interaction modelling.
• Numerical analysis of interaction of trawl gear with buckled pipelines.
• Detailed FEA of strain localisation effects at field joints, forgings and weak joints.
• Analytical and FE analysis of walking (including effects of slope, thermal transients and curve pull-out).
• Global analysis of the interaction between walking and lateral buckling.
• Fracture mechanics and low cycle fatigue assessments (girth weld ECA).
• Reliability analyses, to optimise buckle spacing.

Practical, optimised designs are developed, in full compliance with chosen design codes and either SAFEBUCK or DNV RP-F110 guidance.