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Engineering analysis of free spanning pipelines - FatFree

A professional software for engineering analysis of free spanning pipelines according to the DNV Recommended Practice, DNV-RP-F105.

FatFree software is used for the design, assessment and reassessment of submarine pipeline spans in compliance with the DNV Recommended Practice DNV-RP-F105. The software enables you to design fatigue lifetime for new free spanning pipelines due to Vortex Induced Vibrations and direct wave loading and re-assess fatigue lifetime of pipelines in operation. It supports the requirements for free spanning pipelines according to recognised design standards such as e.g. DNV-ST-F101, API RP 1111 and ASME B31.8

What can FatFree do for you?

  • Help you make a safe engineering analysis of free spans under environmental loads.
  • Helps you decide about the need to correct or intervene a span, helping to save costs related to free span correction
  • Supports the use of modern limit state Recommended Practice, and the performance of more detailed assessments which may lead to increased fatigue life calculations.

Improved decision making with FatFree

  • Calculates fatigue life due to inline and crossflow vortex induced vibrations, direct wave loading, and crossflow wave induced vibration at low KC
  • ‘No wave’ mode suitable for current-dominated VIV, e.g. for deep waters or river crossings
  • Supports safe engineering analysis for maximum allowable free span
  • Improves decision-making on correction or intervention of a span
  • Saves costs on unnecessary free span corrections
  • Recommended Practice based on modern limit state principles
  • Assesses first and higher order modes (multi-mode assessment)
  • Assesses interacting free spans
  • Uses built-in models for pipe-soil interaction, fatigue (SN) curves and vibration response, or
  • Uses detailed user defined response data from e.g. Finite Element Analysis or other sources, for increased accuracy and further reduction in conservatism 
  • Calculates stresses in two hotspots, e.g. at root and toe girth weld, in one go

Have a lot of freespans?...DNV now offers a FatFree REST API service

FatFree REST API provides seamless integration with your in-house business systems, resulting in improved productivity and flexibility. The API provides the API definition and code examples to aid in the integration process.

Buy FatFree REST API now

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  DNV-ST-F101 Code Compliance

DNV-ST-F101 Code Compliance

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Pipeline Engineering Tool - flier

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