Tensioner Best Practice
1.Tensioner components only provide axial restraint (spring type model) to the pipeline. As a result, the lateral and vertical restraints of the tensioner tracks need to be captured using a suitable additional Support component, often a Zero-Gap O Support.
2.It is worth remembering the internal procedure PipeLay follows when capturing the presence of a tensioner. During the static analysis sequence temporary translational boundary conditions support the pipe instead of the tensioner until the very last analysis step (Tension Static step) at which point the temporary conditions are released and the tensioner provides a constant restoring force to the pipeline based on the predicted tension from the previous static step. This predicted tension is usually controlled by a suitable tension criterion on the Analysis component. By default, the tensioner applies the same constant force during dynamic analysis as well unless a characteristic curve or damper coefficient has been selected by the user. For reference the Rio Pipelines 2009 paper, “A Novel Approach to Pipeline Tensioner Modelling”, outlines a case study of the different dynamic tensioner behaviours in PipeLay.
3.The active damper option is the quickest way of achieving a set variation in tensioner tension during dynamics.
4.Further best practice on dynamic tensioner behaviour is discussed under the Criteria Tab Best Practice.