API TR 6AF1 : 1998

Table of Contents

1 Scope
2 References
3 Introduction to rating charts
3.1 Introduction and scope
3.2 Material categories
3.3 Flange combined load capacities
3.4 Use of rating charts
4 Axisymmetric finite element analysis
4.1 Introduction
4.2 Finite element modeling
4.3 Assumptions
4.4 Material categories
4.5 Load cases
4.6 Analysis results
5 Flange combined load capacities
5.1 Introduction
5.2 Allowable stress criteria
5.3 Leak criteria
5.4 Stress linearization
5.5 Load rating methodology
5.6 Results
5.7 Use of rating charts
6 Conclusions and recommendations
6.1 Summary
6.2 Conclusion
6.3 Recommendation
Appendix A - Material category A
Appendix B - Material category B
Appendix C - Material category C
Appendix D - Material category D
Appendix E - Material category E
Appendix F - Material category F
Figures
1 Typical combined load capacity results
2 Load capacity results to use with example problems
3 Typical finite element meshes
4 Convection coefficients for air blowing across a 1-Ft
     diameter cylinder as a function of wind speed and temperature
5 Load conditions for makeup and pressure
6 Load conditions for tension and bending moment
7 Load conditions for thermal and thermal stress analysis
8 Typical stress intensity contour plots for makeup and pressure
     load conditions 7 1/6" 10,000 6BX flange
9 Typical stress intensity contour plots for tension and
     bending moment load conditions
10 Typical contour plots for thermal analysis load conditions
     7 1/16" 10,000 6BX flange
11 Typical stress intensity contour plots for makeup and pressure
     load conditions 2 1/16" 2,000 6B flange
12 Typical stress intensity contour plots for tension and bending
     moment load conditions 2 1/16" 2,000 6B flange
13 Typical contour plots for thermal analysis load conditions
     2 1/16" 8,000 6B flange
14 Typical combined load capacity results
15 Load capacity results to use with example problems
Tables
1 List of materials
2 Derated values of material properties
3 List of materials
4 Derated values of material properties
5 API physical properties and material types
6 Controlling criteria identification numbers

Abstract

This report is a continuation to the report on the capabilities of flanges under combined loadings (PRAC 86-21) which resulted in the publication of API 6AF. Included is an in depth look into the effect of elevated temperatures of API flanges. The results are analytical and assume a temperature gradient across the flange as given in this report.

General Product Information

Published
Document Type	Standard
Status	Current
Publisher	American Petroleum Institute
Pages
ISBN