Showing posts with label DNV. Show all posts
Showing posts with label DNV. Show all posts

Contents of the DNV Offshore Codes Collection

Link:
DNV Offshore Codes Collection
DNV Offshore Codes Amendments and Correction, April 2009

On-bottom Stability

Submarine pipelines stability is very important to ensure that pipelines subjected to environmental loadings stay acceptably stable resting on/buried under seabed. In other words, pipelines submerged weight must be more than hydrodynamic force to avoid flotation or lateral movements.



******************************DNV-RP-F109******************************
Design Methods:

  • Vertical stability in water
  • Vertical stability in/on soil
  • Dynamic lateral stability analysis
  • Generalize lateral stability method
  • Absolute lateral stability static method
Download:
DNV RP F109


******************************DNV-RP-E305******************************
Design Methods:
  • Dynamic method ( dynamic simulation of pipelines under the action of waves and current)
  • Generalized method (use of a set of non-dimensional parameters to generalize Dynamic Analysis Results)
  • Simplified Static Stability method (quasi-static equilibrium approach) SUITABLE for most of the design cases
Download:
ON-BOTTOM STABILITY ANALYSIS AND DESIGN OF SUBMARINE PIPELINE : Mohd. Ridza (THESIS)


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DNV-RP-F110 Global Buckling of Submarine Pipelines

DNV RP F110
Design: Limit State
Edition: 2007

"Global buckling implies that buckling of pipe as a bar in compression. It is a response to compressive effective axial force and not a failure mode."

Objective
  1. To prevent global buckling for burried pipelines.
  2. Allow exposed pipelines to buckle in controlled condition.

Scope

  1. Design of 10" - 42" rigid pipelines.
  2. ONLY limited to local bukling check.
  3. Scenarios covered are exposed pipelines on even seabed and uneven seabed and burried pipelines.
  4. Trawl interference only limited to lateral buckling.

Design

Effective Force wil be limited to residual lay tension, N after pipeline installation. During operation, temperature and pressure will increase contributed to maxinum compresive/restrained effective force, S0 .

Global buckling will occur if the restrained effective axial force (compression), So reach the initial effective axial force, Seff .

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