Safe Design of Hot On-Bottom Pipelines with Lateral Buckling (SAFEBUCK)

Subsea pipelines are increasingly being required to operate at higher temperatures and pressures. The natural tendency of a pipeline is to relieve the resulting high axial stress in the pipe-wall by buckling. Such uncontrolled buckling can have serious consequences for the integrity of a pipeline. Consequently, to date, the industry has sought to restrain pipelines by trenching and burying, or relieving the stress with in-line expansion spools. A far more elegant and cost-effective solution is to work with rather than against the pipeline by controlling the formation of lateral buckles along the pipeline. Controlled lateral buckling is an efficient solution to the relief of axial compression. Indeed, as temperature and pressures increase further, lateral buckling may be the only economic solution. Unfortunately, the industry's understanding of lateral buckling is not mature enough to deliver a demonstrably safe and effective lateral buckling solution. The SAFEBUCK JIP has been initiated to address this issue. The aim of the JIP is to improve understanding of lateral buckling, to enable the safe design of hot on-bottom pipelines with lateral buckling as a high integrity, readily applied solution.

The workscope involves engineering studies and preparation of a lateral buckling design guideline by Boreas, with assessment and testing of flowline materials performance by TWI and geotechnical testing of pipe-soil interaction by Cambridge University Engineering Department. OTM Consulting is managing the JIP on behalf of the JIP partners. SAFEBUCK JIP will deliver the first ever design guideline for on-bottom lateral buckling (single pipe and pipe-in-pipe), unique predictive models for laterally buckled pipeline behavior, innovative methods for initiating and controlling lateral buckling, investigations into the integrity of single pipe and pipe-in-pipe joints through both engineering studies and full-scale testing and investigations into pipe-soil interaction for large cyclic displacements with full-scale tests, based on engineering studies.