Abstract
The operation of offshore vessels is directly related to the use of
flexible pipelines. The article describes in detail the analysis of
power, geometric, kinematic and technological parameters that affect the
main operational characteristics of these pipes during their operation
under water, in rough sea conditions and under wind loads. The article
describes the degree of dependence between loads on the pipeline and
velocity of the oncoming flow, the geometry of the pipe and the distance
to the rigid surface of the ship’s hull or the seabed. It was determined
how the flow velocity during parametric oscillations of the pipeline in
unrestricted flow and near the surface of the seabed affects the change
in its drag and lift coefficients. An estimate of operational limits of
flexible pipeline instability was obtained. On the base of changes in
distributed load, specific values for safe lengths of pipelines were
formulated. It has been stated that the probability of failure-free
operation of a flexible pipeline at a level of 0.99 is directly
determined by the frequency of its oscillation. Its numerical values
should always be at a level that does not exceed 3.7% of the frequency
of pipe dynamic oscillations.