DNV Jacket Tubular Joint Workshop 2022

Join our in-person workshop and learn how to convert a jacket tubular joint to a shell model in less than 5 minutes for use in stress and fatigue analysis

Predicting the fatigue life of an offshore new build or the remaining fatigue life of an existing asset are key factors when deciding on the as-built design or thumbs up/down for life extension work. There are several fatigue analysis methods available supporting the requirements of standards like DNV, ISO, or API.

Traditionally, fatigue of offshore jackets and jack-ups has been based on a beam modelling approach and the use of parametric stress concentration factors (SCF). A challenge is that parametric SCF’s are not always capable to reflect the actual tubular joint configuration which can lead to overly conservative, or optimistic fatigue life. Because of this, several industry leaders are using the finite element methodology to determine actual SCF per tubular joints or to do fatigue analysis based on shell theory.

In this workshop, you will learn how to convert a jacket tubular joint built up by beams to a finite element model (shell elements) that can be used to investigate the real acting stresses, calculate SCF for use in beam fatigue analysis or to do shell fatigue analysis.

The workshop is relevant for:

Offshore structural engineers, group leaders, engineering managers, and technical authorities are responsible for the design, re-qualification or conversion of fixed and mobile offshore assets intended for use in the oil and gas or offshore wind sectors.

In this workshop you will learn about:

Conversion of tubular jacket joints including a finite element mesh that will support DNV RP-C203 Chapter 4.2. The demo and your own exercise will show you how we have reduced the time needed to do so from days and weeks to a couple of minutes

Present results from a case study on fatigue of a jacket tubular joint. The fatigue analyses have been done using parametric SCF, calculated SCF and shell fatigue

The presentation, demo and hands-on will be based on Sesam from DNV. The hands-on session will be done on laptops provided by DNV. In case you are interested to try out later, we can arrange installation of Sesam on your own laptop.

Agenda:

8:30 AM -09:00 AM - Coffee and networking

09:00 -09:45 - The principles behind conversion of tubular joints and creation of the finite element mesh

09:45 -10:00 - Case study on fatigue analysis of a tubular jacket joint – by use of parametric SCF, calculated SCF, and shell fatigue

10:00 -10:15 - Coffee and light refreshment break

10:15 -10:45 - The steps to convert tubular jacket joints to shell elements in just a couple of minutes

10:45 -12:00 - Hands-on session

You'll convert a jacket tubular joint, run a complete jacket analysis (including hydrodynamic and pile/soil) and look at shell stress results of the converted joint

12:00 -13:00 - Networking lunch

Presenter

Ole Jan Nekstad, Business Development Director for Renewables and Ocean Structures (Digital Solutions), took his M.Sc. in offshore engineering from NTH (now NTNU), Trondheim, Norway in 1981. He has since then worked for DNV and has done numerous FE analyses of ships, semi-submersibles, GBS and jackets. He joined the software part of DNV in 1989 and has since 1994 been looking after Sesam as its product director. He was project manager of the JIP “Sesam 2000” that lead to the Sesam as of today.

For questions about this event or registration, please email Glenn Davis at [email protected].

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Host or Publisher DNV GL - Digital Solutions