The Research Of Collision For A Pair Of Marine Risers

Riser as an important component of marine engineering, it can be functionally divided into drilling risers, water injection risers, oil risers and so on. Due to the risers being in complex environmental conditions for long time, it may occur to collide between adjacent risers, the collision would reduce the carrying capacity of the risers, and it may even cause damage to the risers.This article is based on the2012annual national nonprofit quality research, the item number is201210026. Sub-topics of the research is Safety assessment of offshore oil platform pressure piping based on risk management. This article took the top tension oil risers as the study target, analyzed the impact factors of the collision between risers, expected to pave the way for safety assessment and the design of marine riser with collision of riser.This article depended on the classified summary of riser loads, analyzed mechanism of collision between the risers, used CFD software to simulate the flow field situation around risers between adjacent risers in different parameters, these were facilitate to a better understand of the mechanism of the riser colliding. Then used the finite element software ABAQUS, set restart analysis, imported the results of static analysis steps in dynamic analysis steps, simulated local opposition collision of risers. Analyzed the response of collide from the univariate of speed, angle, internal pressure in the presence of friction and frictionless, and then analyzed the impact of riser with chloroprene rubber protective layer, then made a comparative study with bare risers. Based on the single-factor tests, this article tried to use the Box-Behnken test of Design-Expert software to analysis the impact of speed, angle and internal pressure on the collision pressure by the response surface methodology, then fitting conditions of maximum collision stress, and established the condition of finite element model validation. The error between the results of finite element model validation and the response surface methodology did not exceed3%.