DNV—GL — RISER INTERFERENCE

The DNV GL recommended practice relating to the riser interference. Today it is critically important to have an accurate methodology for the assessment of the riser interference, taking into account that the offshore exploration of oil and gas is moving to deeper waters. This, in turn, is causing increased risk of interference between risers. The general design practice traditionally applied to the marine risers is that the collisions must not be allowed under any conditions, from normal to extreme.

The present DNV GL publication is considering the established design analysis procedures as well as criteria applicable for the assessment of the marine riser interference. The objective of the volume is to provide the recommendation relating to the methodology for the engineering analysis as well as to give the rational criteria and technical guidance.

Apart from the introduction, the content of the document is arranged in four major parts covering the design approach mentioned above, hydrodynamic interaction, marine riser clearance assessment, and the one providing references. There are also three appendices giving information about the phenomenon of hydrodynamic interaction, analysis of the local impact stress applied to the steel pipes, and relevant analysis considerations.