1、Technical Report on Capabilities of API Integral Flanges Under Combination of LoadingPhase IIAPI TECHNICAL REPORT 6AF2 FIFTH EDITION, APRIL 2013Special NotesAPI publications necessarily address problems of a general nature. With respect to particular circumstances, local, state, and federal laws and
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14、.C. 20005.Suggested revisions are invited and should be submitted to the Standards Department, API, 1220 L Street, NW, Washington, D.C. 20005, standardsapi.org.iiiContentsPage1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15、 . . . . . . . . . . . . . . . . . . . . . . . 12 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Three-dimensional Finite Element Analysis. . . . . . . . . . . . . . . . . . . .
16、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.1 Finite Element Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.2 Finite Element Results . . . . . . . . . . . . . . . . . . . . . . .
17、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Two-dimensional Heat Transfer Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184.1 Finite Element Modeling . . . . . . . . . . . . . . . . . .
18、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184.2 Temperature Analysis Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Limiting Criteria for Combined Loading . .
19、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215.2 Leakage Criterion .
20、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215.3 Stress Criterion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、 . . . . 235.4 Development of Load Combination Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255.5 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
22、. . . . . . . . . . . . . . 266 Reanalysis of Failed Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317 Effect of Lockdown Screw Holes on Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
23、. . . . . . . . . . . . . . 318 Conclusion and Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Annex AComparison Between Prac 86-21 and Prac 88-21 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24、 . 40Annex BLoad Combination Charts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Tables1 Nodal Temperatures for Typical Type 6BX Flanges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、202 Adopted Stress Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233 Flanges That Did Not Meet Makeup-only Criterion, Makeup = 52.5 ksi. . . . . . . . . . . . . . . . . . . . . . . . . . . . 334 Flange Geo
26、metry Modifications to Meet ASME Criterion for 52.5 ksi Makeup . . . . . . . . . . . . . . . . . . . . . 335 Lockdown Screw Holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336 Effect of Lockdown Screw Holes on
27、Flange Stiffnesses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 Effect of Lockdown Screw Holes on Flange Combined Load Capability . . . . . . . . . . . . . . . . . . . . . . . . . . 348 Modification Coefficients for Bending Capacity at Zero Tension and Zero Press
28、ure . . . . . . . . . . . . . . . . 34A.1 Comparison for Type 6B Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41A.2 Comparison for Type 6BX Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
29、 . . . . . . . . . . . . . . . . . . . . 42B.1 Makeup Values for Flanges with Stress Criterion Governing at Least for Part of the Range of the Load Combination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Figures1 A Typical F
30、inite Element Model of Flange and Bolt Superelements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Unit Load Cases. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Superelemental H
31、ierarchy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 Gasket Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32、. . 85 Typical Lotus 1-2-3 Worksheet for Calculating Equivalent Stresses Due to Applied Forces. . . . . . . . . . . 96 Equivalent Stresses Due to Applied Bending Moment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Deflected Shape Due to Unit Makeup (1.0 ksi).
33、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 Deflected Shape Due to Unit Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 Deflected Shape Due to Unit Tension (1.0 kip). . . .
34、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1210 Deflected Shape Due to Bending Moment (1.0 K.in.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13vPage11 Maximum Shear Stress Contours Due to Unit Makeup . . . . . . .
35、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1312 Maximum Shear Stress Contours Due to Unit Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1413 Maximum Shear Stress Contours Due to Unit Tension . . . . . . . . . . . . . . . . . . . . . . .
36、 . . . . . . . . . . . . . . . . . 1414 Maximum Shear Stress Contours Due to Unit Bending Moment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1515 Von Mises Equivalent Stress Contours for 2 1/16 in. 3,000 psi Type 6B Flange Under 52.5 ksi Makeup and 6,000 psi Test Pressure. . . .
37、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1516 Bolt Stress (z) Contours for Unit Makeup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1617 Bolt Stress (z) Contours for Unit Pressure
38、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1618 Bolt Stress (z) Contours for Unit Tension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1719 Bolt Stress (z) Contours for Unit Bending Mome
39、nt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1720 Typical Heat Conduction 2-D Mesh for Type 6BX Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1921 Typical Leakage Load Combination Charts for 52.5 ksi and 40 ksi Makeup Loads
40、. . . . . . . . . . . . . . . . . 2222 Stress Linearization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2423 Critical Section Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
41、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2524 Comparison Between 2-D and 3-D Results for Leakage Criteria for 2 1/16 in. 3,000 psi 6B Flange . . . . . 2725 Comparison Between 2-D and 3-D Results for Leakage Criteria for 16 3/4 in. 3,000 psi 6B Flange. . . . . 2726 Stress Limiting C
42、riteria for 2 1/16 in. 3,000 psi 6B Flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2827 Stress Limiting Criteria for 16 3/4 in. 3,000 psi 6B Flange. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2828 Leakage Criteria with Temperatur
43、e Effect for 2 1/16 in. 3,000 psi 6B Flange. . . . . . . . . . . . . . . . . . . . . . . . 2929 Leakage Criteria with Temperature Effect for 16 3/4 in. 3,000 psi 6B Flange . . . . . . . . . . . . . . . . . . . . . . . 2930 Stress Criterion with Temperature Effect for 2 1/16 in. 3,000 psi 6B Flange .
44、 . . . . . . . . . . . . . . . . . . . . . . . 3031 Stress Criterion with Temperature Effect for 16 3/4 in. 3,000 psi 6B Flange . . . . . . . . . . . . . . . . . . . . . . . . 3032 Bolt Stress Contours for 5 1/8 in. 10,000 psi Type 6BX Flange. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
45、. . . . . . 3233 Bolt Stress Contours for 11 in. 10,000 psi Type 6BX Flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3234 Finite Element Model of Flange with Lockdown Screw Holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3535 Effect of Lockd
46、own Screw Holes on Leakage Charts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3636 Effect of Lockdown Screw Holes on Stress Charts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37A.1 Hopper Chart (from ASME Boiler and Pr
47、essure Vessel Code, Appendix 4). . . . . . . . . . . . . . . . . . . . . . . . 441Technical Report on Capabilities of API Integral Flanges Under Combination of LoadingPhase II1 ScopeThe evaluation of the load carrying capacity of API 6A integral flanges is the objective of this work. The applied loa
48、ding includes the end tension and bending moment in addition to the conventional rated pressure and makeup forces. The effect of a temperature difference corresponding to 250 F on the inside and 30 F on the outside was also evaluated.Three-dimensional finite element meshes were generated for the Typ
49、e 6B, and Type 6BX flanges. The bending moment load case required a model of one quarter of the flange which was built up from the smaller segments and the half-bolt superelements. The computer program SESAM was used to obtain the stresses at selected critical flange and hub sections and to determine the gasket reaction due to each of the four unit load cases and the temperature difference load case. Leakage criterion was defined as the load combination which reduces the initial makeup compressive forces in the gasket to zero. The stresses in each defined section were linearize
