Fatigue Life Improvement of an Autofrettage Thick-Walled Pressure Vessel with an External Groove

Abstract

This report presents an investigation into a fatigue life improvement of an autofrettaged thick-walled pressure vessel with an external groove subjected to pulsating internal pressure, along with mean strain and mean stress effects on strain-controlled low cycle fatigue behavior. Linear elastic stress analysis of an autofrettaged thick-walled pressure vessel with an external groove is done using a finite element method. Autofrettage loading is performed using a thermal loading analogy. Change of external groove geometry is made using a quasi-optimization technique and finite element method to achieve longer fatigue life by relieving the stress concentration at the groove root. Surface treatment using shot peening is employed to produce compressive residual stresses at the vulnerable surface of the groove root to counteract the high tensile stresses. An evaluation of the fatigue life of an autofrettaged thick- walled pressure vessel with an external groove is done through a series of simulation fatigue tests using C-shaped specimens taken from the thick-walled pressure vessel. Autofrettage, Pressure Vessels, Thick Walls, Grooves, Fatigue Life.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1992
Accession Number
ADA247233

Entities

People

  • Ralph I. Stephens
  • Seung K. Koh

Organizations

  • University of Iowa

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Computational Fluid Dynamics
  • Computational Science
  • Creep
  • Finite Element Analysis
  • Fracture (Mechanics)
  • Geometry
  • Linear Regression Analysis
  • Materials
  • Materials Science
  • Mechanical Working
  • Mechanics
  • Modulus Of Elasticity
  • Notch Sensitivity
  • Regression Analysis
  • Shot Peening
  • Stress Strain Relations
  • Surface Roughness

Fields of Study

  • Engineering

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Structural Health Monitoring of Composite Structures.