STP-PT-025 Designator: Meta Bold 24/26 Revision Note: Meta Black 14/16 EXTENDED FATIGUE EXEMPTION RULES FOR LOW CR ALLOYS INTO THE TIME-DEPENDENT RANGE FOR SECTION VIII DIV STP-PT-025 EXTEND FATIGUE EXEMPTION RULES FOR LOW CR ALLOYS INTO THE TIME-DEPENDENT RANGE FOR SECTION VIII DIV CONSTRUCTION Prepared by: Charles Becht IV, PhD, PE Charles Becht V Becht Engineering Company Date of Issuance: January 29, 2009 This report was prepared as an account of work sponsored by ASME Pressure Technologies Codes and Standards and the ASME Standards Technology, LLC (ASME ST-LLC) Neither ASME, ASME ST-LLC, the authors, nor others involved in the preparation or review of this report, nor any of their respective employees, members, or persons acting on their behalf, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe upon privately owned rights Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by ASME ST-LLC or others involved in the preparation or review of this report, or any agency thereof The views and opinions of the authors, contributors, reviewers of the report expressed herein not necessarily reflect those of ASME ST-LLC or others involved in the preparation or review of this report, or any agency thereof ASME ST-LLC does not take any position with respect to the validity of any patent rights asserted in connection with any items mentioned in this document, and does not undertake to insure anyone utilizing a publication against liability for infringement of any applicable Letters Patent, nor assumes any such liability Users of a publication are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, is entirely their own responsibility Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted as government or industry endorsement of this publication ASME is the registered trademark of the American Society of Mechanical Engineers No part of this document may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher ASME Standards Technology, LLC Three Park Avenue, New York, NY 10016-5990 ISBN No 978-0-7918-3190-8 Copyright © 2009 by ASME Standards Technology, LLC All Rights Reserved Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 TABLE OF CONTENTS Foreword v Abstract vi BACKGROUND SHAKEDOWN CONCEPTS STRAIN RANGE FOR SHAKEDOWN AND INITIAL STRESS CREEP FATIGUE WITH SHAKEDOWN TO ELASTIC ACTION DEMONSTRATION OF SHAKEDOWN 11 INTERMEDIATE CYCLES 12 LOW CYCLE EXEMPTION 14 CONCLUSION 16 References 17 Appendix A - Relaxation/Damage Accumulation Curves 19 Appendix B - Cyclic Fatigue Data and Charts 22 Appendix C - Gr 22 Data Tables 32 Appendix D - Gr 91 Data Points 43 Acknowledgments 57 LIST OF TABLES Table - Relaxation/Damage Accumulation Data for Various Chrome Alloys LIST OF FIGURES Figure – Strain Range vs Cycles to Failure Figure – Stress-Strain Behavior Illustrating Shakedown Figure – Stress-Strain Behavior Illustrating Elevated Temperature Shakedown Figure – Cyclic Stress History with Shakedown Figure – Cyclic Stress History Without Shakedown Figure – Stress-Strain Behavior with Reset to Allowable Stress Figure – Cyclic Stress History with Reset to Allowable Stress Figure - Relaxation/Damage Accumulation Curves for 1.25Cr-0.5Mo-Class Material Figure - Creep-Fatigue Interaction Diagram 10 Figure 10 – Stress Strain Behavior with Stress Reset Caused by Relaxation at Second Operating Condition 12 Figure 11 – Stress-Time Behavior with Stress Reset Caused by Relaxation at Second Operating Condition 13 Figure 12 - Nozzle Subjected to Internal Pressure with High Peak Stress at the Acute Corner [10] 14 iii STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range Figure 13 - Stress, Plastic and Creep Strain, Strain Limit Ratio and Damage After 10 Cycles with Year Hold Time [10] 14 Figure 14 - 9Cr-1Mo-V 900°F 19 Figure 15 - 2.25Cr-1Mo-V 900°F .19 Figure 16 - 2.25Cr-1Mo Class 900°F 20 Figure 17 - 2.25Cr-1Mo Class 900°F 20 Figure 18 - 1.25Cr-0.5Mo-Si Class 900°F .21 Figure 19 - 1.25Cr-0.5Mo-Si Class 900°F .21 Figure 20 - 1.25Cr-0.5Mo-Si-Class Data Point Plotted Versus SCMV Material (45/75 grade [bainitic]) which has Exhibited Similar Behavior to 1.25Cr Alloys.[12] 23 Figure 21 - 1.25Cr-0.5Mo-Si-Class Data Point Plotted Versus Various Alloys with Similar Behavior to 1.25Cr Alloys.[13] 23 Figure 22 - 2.25Cr-1Mo Class Data Point Plotted Versus 2.25Cr-1Mo Steel Whose Heat Treatment was Normalization and Tempering Followed by Stress Relief Annealing.[14] 24 Figure 23 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for Annealed 2.25Cr1Mo Steel Note that this data does not appear to match any of the other data compiled during this investigation.[15] 25 Figure 24 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for PWHT and QT (both bainitic) 2.25Cr-1Mo Steel.[15] 25 Figure 25 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for 2.25Cr-1Mo Steel Class 2.[16] 26 Figure 26 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for 2.25Cr-1Mo Steel Class 2, Note HAZ stands for heat affected zone.[16] 26 Figure 27 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for Normalized and Tempered 2.25Cr-1Mo Steel.[17] .27 Figure 28 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for Normalized and Tempered 2.25Cr-1Mo Steel.[18] .27 Figure 29 - 2.25Cr-1Mo Class Data Point Plotted Versus Fatigue Data for Normalized and Tempered 2.25Cr-1Mo Steel.[19] .28 Figure 30 - 2.25Cr-1Mo-V Data Point Plotted Versus Fatigue Data for 2.25Cr-1Mo-V Steel.[20] 28 Figure 31 – 9Cr-1Mo-V Data Point Plotted Versus Fatigue Data for 9Cr-1Mo-V Steel [See App D] 29 Figure 32 - 9Cr-1Mo-V Data Point Plotted Versus Fatigue Data for 9Cr-1Mo-V Steel [See App D] 29 Figure 33 - 9Cr-1Mo-V Data Point Plotted Versus Fatigue Data for 9Cr-1Mo-V Steel.[21] .30 Figure 34 - 9Cr-1Mo-V Data Point Plotted Versus Fatigue Data for 9Cr-1Mo-V Steel.[21] .30 Figure 35 - 9Cr-1Mo-V Data Point Plotted Versus Fatigue Data for 9Cr-1Mo-V Steel [See App D] 31 iv Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 FOREWORD This document was developed under a research and development project which resulted from ASME Pressure Technology Codes & Standards (PTCS) committee requests to identify, prioritize and address technology gaps in current or new PTCS Codes, Standards and Guidelines This project is one of several included for ASME fiscal year 2008 sponsorship which are intended to establish and maintain the technical relevance of ASME codes and standards products The specific project related to this document is project 07-03 (BPVC#1), entitled “Extend Fatigue Exemption Rules for Low Cr Alloys Slightly into the Time-Dependent Range for Section VIII Div Construction.” Established in 1880, the American Society of Mechanical Engineers (ASME) is a professional notfor-profit organization with more than 127,000 members promoting the art, science and practice of mechanical and multidisciplinary engineering and allied sciences ASME develops codes and standards that enhance public safety, and provides lifelong learning and technical exchange opportunities benefiting the engineering and technology community Visit www.asme.org for more information The ASME Standards Technology, LLC (ASME ST-LLC) is a not-for-profit Limited Liability Company, with ASME as the sole member, formed in 2004 to carry out work related to newly commercialized technology The ASME ST-LLC mission includes meeting the needs of industry and government by providing new standards-related products and services, which advance the application of emerging and newly commercialized science and technology, and providing the research and technology development needed to establish and maintain the technical relevance of codes and standards Visit www.stllc.asme.org for more information v STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range ABSTRACT A number of alloys have applications slightly into the creep range that are in cyclic service, such as process reactors The 2007 edition of Section VIII, Div [1] provides allowable stresses for these materials, which may be controlled by creep properties However, the fatigue design rules and fatigue exemption rules are not applicable, precluding construction of vessels using these materials at temperatures above 370°C (700°F) This report provides a simplified approach for exemption of low chrome alloys from fatigue analysis that are slightly into the creep range vi Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 BACKGROUND A number of alloys have applications slightly into the creep range that are in cyclic service, such as process reactors The 2007 edition of Section VIII, Div [1] provides allowable stresses for these materials, which may be controlled by creep properties However, the fatigue design rules and fatigue exemption rules are not applicable The fatigue exemption rule of Section VIII, Div 2, Part 5, paragraph 5.5.2.2, which permits exemption by prior experience, is not applicable since prior experience with vessels constructed to the new design margins provided in the 2007 edition of Div are not applicable In the 2004 edition of Section VIII, Div [2], the maximum temperature for which allowable stresses were provided was limited to temperatures where time independent properties governed the allowable stress, as discussed below However, this does not mean that creep is not significant For example, hold time fatigue data in Figure from reference 3, clearly show a reduction in fatigue life from creep damage associated with hold times, for 2-1/4 Cr – Mo at 482°C (900°F) Perhaps as a result of this, fatigue curves have not been provided for temperatures greater than 370°C (700°F) Fatigue curves based on continuous cycling tests without hold time would be non-conservative for general design These higher temperature vessels can only be designed per the present rules if they satisfy an exemption from fatigue analysis Reducing the margin on tensile strength in the 2007 edition of Section VIII, Div 2, drops the temperature at which creep properties govern to a lower temperature A change was made to specifically consider the effect of creep properties on allowable stress However, the same issue remains, the Div rules can only be used if the component satisfies an exemption from fatigue analysis as there are no fatigue curves in the Code for temperatures greater than 370°C (700°F) For the materials in question, the basis for the allowable stresses in the 2004 edition of Section VIII, Div construction was the least of the following (per ASME Section II, Part D, and Appendix [4]) ST/3 1.1 STRT/3 2/3 Sy 2/3 SYRY From ASME Section II, Part D, these values are defined as: RT ratio of the average temperature dependent trend curve value of tensile strength to the room temperature tensile strength RY ratio of the average temperature dependent trend curve value of yield strength to the room temperature yield strength ST specified minimum tensile strength at room temperature SY specified minimum yield strength at room temperature In Section VIII, Division [5], the following additional considerations in setting the allowable stress are required when the material is in the creep regime Favg SR avg 0.8 SR Sc From ASME Section II, Part D, these values are defined as: STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range Favg multiplier to average stress for rupture in 100,000 hr At 1500°F and below, Favg is 0.67 Above 1500°F, it is determined from the slope of the log time-to-rupture versus log stress plot at 100,000 hr such that Favg = 1/n, but it may not exceed 0.67 Sc average stress to produce a creep rate of 0.01%/1000 hr SR avg average stress to cause rupture at the end 100,000 hr SR minimum stress to cause rupture at the end of 100,000 hr ST specified minimum tensile strength at room temperature, ksi SY specified minimum yield strength at room temperature, ksi n a negative number equal to D log time-to rupture divided by D log stress at 100,000 hr In the 2004 edition maximum, use temperatures were set in Division such that these creep criteria from Division would not govern in setting the allowable stress, if they were considered In the 2007 edition, the margin on tensile strength was reduced from to 2.4 This had the effect of increasing the allowable stress, at some temperatures, to the point where the criteria based on creep properties that are considered in setting the allowable stress would result in a lower allowable stress than the new Div allowable stress based on tensile properties The creep criteria were added to the Div allowable stress basis, and these govern the allowable stress at higher temperatures that are permitted for some materials From the standpoint of design for primary stresses, given that the new Div rules consider creep properties in establishing the allowable stress, the rules provide the same margins as Section VIII, Div As such, in design for primary stresses, no specific further consideration within the scope of this project is required There are, of course, other issues worth considering with respect to the margins on primary stress, such as the effect of weldments Figure – Strain Range vs Cycles to Failure Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 To design for cyclic stresses, additional considerations are required Fatigue tests with hold times each cycle have demonstrated that hold times and the associated creep does have a significant effect at the temperatures of interest, as illustrated in Figure [15] Development of rules for creep-fatigue design is not within the scope of this project Rather, the task is to develop rules that provide for exemption from fatigue analysis Such exemption rules will permit pressure vessels in cyclic service into the temperature ranges where creep becomes significant The specific alloys within the scope of this study include 1-1/4 Cr-1/2 Mo, 2-1/4 Cr-1 Mo, 2-1/4 Cr-1 Mo-V, 9Cr-1 Mo-V and 12 Cr We were not able to obtain any creep fatigue data for 12 Cr and 1-1/4 Cr-1/2 Mo and as a result coverage of these alloys is limited in this report TESTPIECE ID 32 33 34 35 62 66 67 48T 279T 278T 281T 282T 283T 285T 286T 294T 297T 302T 300T 12 14 15 17 13 MATERIAL ID 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 44 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 371 371 371 371 371 23 23 23 23 23 23 23 23 23 23 23 538 593 593 593 593 593 593 593 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt 60 tht thc 0.33 0.36 0.52 0.71 0.32 0.38 0.574 1.072 0.468 0.466 0.464 0.465 0.98 1.46 0.46 0.76 0.41 0.5 0.37 0.63 0.65 % Det 2.ea 0.29 0.32 0.35 0.41 0.38 0.32 0.34 0.38 0.54 0.41 0.4 0.4 0.39 0.49 0.52 0.4 0.33 0.29 0.312 0.29 0.264 0.288 0.4 0.344 % ee 0.04 0.04 0.17 0.3 0.62 0.04 0.19 0.53 0.05 0.06 0.06 0.07 0.49 0.94 0.06 0.67 0.47 0.688 0.12 0.236 0.082 0.23 0.298 % ep 302 333 362 364 374 384 412 433 602 510 444 494 458 545 594 467 MPa smax 327 302 343 351 377 346 351 525 620 432 461 404 426 557 592 435 MPa smin 486 519 458 451 298 415 447 Ds -2.1 -10.5 0.7 4.9 0 sm MPa sh1end MPa sh2end 163100 66834 18984 4528 1975 >1484683 202656 28395 1814 28958 55967 65301 47471 2808 577 71576 1734 2155 1675 47000 9225 695530 6470 4165 cycles Nf COMMENTS STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range TESTPIECE ID 10 16 22 18 24 20 19 21 23 25 11 52T 53T 46T 47T 48T MATERIAL ID 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 45 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 30176 HG-B HG-B HG-B HG-B HG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 538 538 538 538 538 538 538 538 538 538 538 538 538 538 538 482 482 482 482 482 482 482 482 371 371 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt 60 60 tht 60 60 thc 1 0.3 0.4 0.3 0.36 0.36 0.4 0.4 0.5 0.6 0.7 1.5 0.25 0.31 0.37 0.42 0.5 0.68 1 0.26 0.32 % Det 2.ea 0.33 0.22 0.33 0.25 0.32 0.29 0.32 0.3 0.3 0.31 0.34 0.31 0.36 0.37 0.43 0.24 0.25 0.3 0.31 0.34 0.31 0.37 0.33 0.24 0.27 % ee 0.67 0.78 0.67 0.05 0.07 0.01 0.04 0.06 0.1 0.09 0.16 0.29 0.34 0.63 1.07 0.01 0.06 0.07 0.11 0.16 0.37 0.63 0.67 0.02 0.05 % ep 291 262 312 183 232 225 261 236 238 236 260 265 280 285 329 242 255 287 285 302 308 322 318 269 331 MPa smax 348 285 281 283 265 225 244 229 238 238 257 261 277 285 332 250 242 259 276 293 326 326 317 322 318 MPa smin Ds sm 162 159 MPa sh1end 174 190 MPa sh2end 1734 >1208 1176 4456920 52129 190733 30857 40284 42532 12965 10840 4895 3032 1408 1035 >668200 1223675 78300 47114 13001 4147 1388 1481 784843 61130 cycles Nf COMMENTS Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 TESTPIECE ID 537 24-B 54 100T 109T 101T 104T 105T 107T 20 17 18 14 26 22 21 19 16 23 24 15 MATERIAL ID 30176 30176 30176 10148 10148 10148 10148 10148 10148 10148 10148 10148 46 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B HG-B / POSITION ORIENTATION TESTPIECE C 538 538 538 538 538 482 482 482 482 482 371 371 371 371 371 371 22 22 22 22 22 22 593 538 538 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt tht thc 0.48 0.6 0.67 1.5 0.36 0.41 0.51 0.71 0.35 0.37 0.5 0.52 0.71 0.43 0.49 0.54 0.72 1.2 1.5 0.7 0.3 % Det 2.ea 0.34 0.35 0.38 0.39 0.44 0.3 0.32 0.37 0.36 0.38 0.3 0.32 0.35 0.4 0.43 0.42 0.35 0.37 0.37 0.4 0.43 0.46 0.25 % ee 0.14 0.25 0.29 0.61 1.06 0.06 0.09 0.14 0.35 0.62 0.05 0.05 0.15 0.12 0.28 0.58 0.08 0.12 0.17 0.32 0.57 0.74 0.05 % ep 266 266 292 298 328 283 280 311 306 340 333 353 362 357 360 399 416 414 417 455 493 522 183 MPa smax 264 273 292 298 342 275 290 309 306 344 326 342 346 326 361 399 380 434 431 453 495 521 199 MPa smin Ds sm MPa sh1end MPa sh2end 21058 7091 3525 1708 884 514315 115515 12792 4038 2039 89789 124037 8468 24271 8172 1780 43101 26903 16580 8304 2300 957 780 9676 4056920 cycles Nf COMMENTS STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range TESTPIECE ID 11 13 HLB22 HLB36 LLB24 LLB38 HHB25 HHB39 LHB27 LHB40 LHB41 1HG 2HG 4HG 3HG 6HG 7HG 8HG 9HG 10HG 11HG 33 35 32 MATERIAL ID 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 47 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 UG-B UG-B UG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B UG UG UG UG UG UG UG UG UG UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 593 593 593 22 22 22 22 22 22 22 22 22 22 593 593 593 593 593 25 25 25 25 538 538 538 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt 60 30 tht thc 0.5 0.5 0.5 0.33 0.35 0.38 0.4 0.45 0.5 0.7 1.5 0.45 0.45 0.45 1 0.45 0.45 1 0.3 0.33 0.4 % Det 2.ea 0.3 0.18 0.2 0.32 0.32 0.35 0.36 0.28 0.38 0.41 0.45 0.5 0.54 0.25 0.24 0.25 0.28 0.28 0.36 0.35 0.45 0.47 0.27 0.28 0.29 % ee 0.2 0.32 0.3 0.01 0.03 0.03 0.04 0.07 0.12 0.29 0.55 1.46 0.2 0.21 0.2 0.72 0.72 0.09 0.1 0.55 0.53 0.03 0.05 0.11 % ep 245 154 184 272 324 317 369 365 365 430 436 494 541 210 177 207 555 229 372 365 449 428 212 218 229 MPa smax 221 209 242 350 317 374 353 394 391 419 458 497 547 208 177 202 229 234 372 367 455 434 206 205 215 MPa smin Ds sm 83.8 MPa sh1end MPa sh2end 12057 2882 3360 2498943 608149 244016 145540 56070 47139 23571 7192 2778 964 8385 7246 9390 1045 1915 72408 89049 5121 5728 5812800 1081069 84011 cycles Nf COMMENTS Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 TESTPIECE ID 38 37 43 31 202 203 53 44 201 204 205 207 208 E99T E96T E97T E10T 19 20 18 17 16 42 41 23 MATERIAL ID 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 10148 48 10148 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 482 482 482 371 371 371 371 371 22 22 22 22 593 593 593 593 593 593 538 593 593 538 593 593 593 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt 60 60 30 60 30 tht thc 0.51 0.74 0.35 0.47 0.51 0.71 0.35 0.5 0.5 0.7 0.508 0.402 0.356 0.75 0.5 1.06 1.5 0.4 0.5 0.5 0.5 % Det 2.ea 0.37 0.39 0.39 0.31 0.39 0.38 0.42 0.56 0.34 0.42 0.42 0.47 0.328 0.285 0.326 0.37 0.32 0.23 0.26 0.82 0.29 0.26 % ee 0.14 0.36 0.61 0.04 0.08 0.13 0.29 0.44 0.03 0.08 0.08 0.23 0.18 0.117 0.03 0.378 0.68 0.27 0.24 0.18 0.21 0.24 % ep 335 325 338 312 370 355 386 407 355 401 462 478 219 238 200 219 MPa smax 333 323 342 321 357 341 377 393 297 433 400 473 289 249 200 298 MPa smin 526 490 418 502 579 429 Ds -8.6 -25.7 17.6 3.6 2.9 sm 166 77 141 MPa sh1end MPa sh2end 12235 5454 2120 2968478 13125 45081 8633 2740 >6205547 60655 38894 10655 11225 29954 888670 2706 1291 2825 2654 822 23550 6975 400 39500 4150 cycles Nf BUCKLE VACUUM VACUUM VACUUM COMMENTS STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range TESTPIECE ID 39 50 13 14 4HT1 4HT2 E57T E58T C1T? C4T C3T C2T E49T E59T E57T E56T E63T E60T E62T MATERIAL ID 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 49 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 538 538 482 482 482 538 538 538 538 538 538 482 482 538 538 538 538 538 538 538 538 538 538 482 482 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt 0.6 tht 30 15 0.6 thc 0.5 0.5 1 0.4 0.5 0.4 0.5 0.5 0.5 0.3 0.35 0.4 0.5 0.6 0.7 1.5 0.38 0.41 % Det 2.ea 0.3 0.26 0.414 0.409 0.423 0.35 0.37 0.31 0.34 0.4 0.48 0.37 0.43 0.26 0.26 0.31 0.34 0.37 0.35 0.42 0.44 0.32 % ee 0.2 0.24 0.586 0.591 0.577 0.05 0.13 0.09 0.16 0.6 1.52 0.13 0.57 0.04 0.09 0.09 0.16 0.23 0.35 0.58 1.06 0.09 % ep 298 272 345 363 379 234 283 241 259 305 372 300 379 201 196 245 266 285 276 322 343 258 288 MPa smax 221 203 379 366 387 307 284 241 262 314 369 305 387 201 198 238 269 288 280 322 336 297 279 MPa smin Ds sm 303 MPa sh1end 165 134 310 MPa sh2end 5173 8840 3594 2387 2990 218889 43038 382381 52400 3827 631 118710 2990 13706 3694 4055050 668248 37666 13786 6858 6844 1728 767 109467 cycles Nf TESTED AT ANL TESTED AT ANL COMMENTS Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 TESTPIECE ID E50T E49T E51T E52T E55T 1A 3A E54T E61T 48 29 38 53 47 52 51 31 37 30 57 56 55 54 70 MATERIAL ID 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 50 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 30394 UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B / POSITION ORIENTATION TESTPIECE C 538 593 593 593 593 593 538 593 593 593 593 593 593 538 593 593 593 538 538 538 538 538 538 538 538 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.1 0.1 0.4 0.4 %/s de/dt 15 15 60 60 60 tht 15 60 60 60 0.6 thc 0.78 0.41 0.584 1.08 0.78 0.5 0.78 0.35 0.5 1.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 2 0.5 0.5 0.63 0.5 0.5 % Det 2.ea 0.26 0.372 0.38 0.3 0.26 0.23 0.31 0.34 0.38 0.48 0.28 0.39 0.52 0.37 0.34 % ee 0.15 0.212 0.7 0.48 0.52 0.27 0.19 1.66 1.62 1.52 0.22 0.11 0.11 0.13 0.16 % ep 259 310 325 386 372 277 296 399 283 286 MPa smax 181 217 369 362 369 199 307 390 284 261 MPa smin 418 520 615 515 482 Ds 2.1 -3.5 -8.4 -3.5 sm MPa sh1end 100 129 161 193 151 239 MPa sh2end 1081 81855 11831 1676 2640 15992 2894 75796 6013 826 3207 7420 13125 15455 2485 6500 3523 530 392 631 >7035 29883 >6812 43038 19291 cycles Nf BUCKLE Gieseke paper- 3537 Nf BUCKLE CRACK PRESENT COMMENTS STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range TESTPIECE ID 28 43 32 40 45 58 35 E4T E5T E27 E3T 72T 73T 74T 58T 46T 68T 48T 30T 26T 27T 31T 28T 32T 29T MATERIAL ID 30394 30394 30394 30394 30394 30394 30394 30182 30182 30182 30182 91887 51 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 593 593 593 593 593 593 593 538 538 538 538 593 593 593 538 538 538 538 538 538 593 538 538 538 593 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 %/s de/dt 180 15 30 15 120 tht thc 0.3 0.41 0.51 0.65 0.81 1.01 1.75 0.4 0.5 0.51 0.45 0.5 0.4 0.5 0.5 0.5 0.7 0.35 0.78 0.78 0.78 0.5 % Det 2.ea 0.16 0.18 0.25 0.24 0.31 0.32 0.22 0.28 0.31 0.37 0.36 0.26 0.27 0.32 0.3 0.38 0.33 0.37 % ee 0.14 0.23 0.26 0.41 0.5 0.69 1.53 0.12 0.19 0.14 0.64 0.19 0.23 0.68 0.1 0.12 0.17 0.63 % ep 143 140 210 208 245 254 262 210 238 272 274 176 184 223 224 283 246 279 MPa smax 119 155 199 189 275 291 243 224 241 286 286 188 195 238 243 307 263 286 MPa smin Ds sm MPa sh1end MPa sh2end 11800000 299707 29136 10916 3726 2818 1303 260770 25775 22316 2951 139477 110377 7432 62227 5708 21810 2907 3113 2943 22541 308 1530 3351 cycles Nf INEL 593C OR 538C? INEL 593C OR 538C? INEL 593C OR 538C? INEL 593C OR 538C? INEL 593C OR 538C? INEL 593C OR 538C? INEL 593C OR 538C? BAD TEST? BAD TEST? CONTROL OUTAGE VACUUM COMMENTS Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 TESTPIECE ID 53T 50T 52T 57T 59T 64T 34T 36T 60T 62T 63T 65T 66T 67T 70T 64T 213 227 209 219 232 230 231 206 225 MATERIAL ID 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 91887 52 91887 91887 91887 30383B 30383B 30383B 30383B 30383B 30383B 30383B 30383B 30383B 30383B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B UG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B HG-B / POSITION ORIENTATION TESTPIECE C 593 593 593 593 593 593 593 593 593 538 593 593 593 593 593 593 593 538 538 538 538 538 538 538 538 ° TEMP 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.1 %/s de/dt 60 60 0.6 tht 60 30 30 60 6 0.6 thc 1.5 0.41 0.79 0.5 0.5 0.35 0.75 0.4 0.51 0.51 0.51 1 0.5 1 1 0.55 0.5 0.5 0.5 0.5 % Det 2.ea 0.351 0.34 0.27 0.33 0.32 0.32 0.28 0.23 0.27 0.27 0.32 0.41 0.19 0.18 0.31 0.38 0.31 0.26 0.28 0.26 % ee 0.348 1.16 0.14 0.46 0.68 0.19 0.23 0.28 0.73 0.73 0.18 0.59 0.81 0.82 0.69 17 0.18 0.24 0.22 0.24 % ep 332 202 260 177 257 252 218 283 182 227 300 288 241 241 231 193 MPa smax 300 358 193 244 307 245 234 293 186 283 279 303 238 200 224 241 MPa smin 531 609 446 531 Ds 3.5 7.2 3.5 -1.7 sm 113 81 76 71 MPa sh1end 159 134 131 35 172 162 200 159 MPa sh2end 1376 715 11986 1574 11790 11744 246089 2445 41000 1278 >2926 6365 4202 1081 933 64362 3308 1190 1584 989 134606 8135 9917 12368 >40911 cycles Nf HOLD AT O TENSION GOING COMMENTS STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range TESTPIECE ID 216 201 206B 208 226 MATERIAL ID 30383B 30383B 30383B 30383B 30383B UG-B UG-B UG-B UG-B UG-B / POSITION ORIENTATION TESTPIECE C 593 593 593 593 593 ° TEMP 0.4 %/s de/dt tht thc 0.5 0.5 0.5 0.5 0.35 % Det 2.ea % ee % ep MPa smax MPa smin Ds sm MPa sh1end MPa sh2end 3955 1149 637 2643 33476 cycles Nf SRP TESTS SRP TESTS SRP TESTS SRP TESTS COMMENTS Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range 53 STP-PT-025 STP-PT-025 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range References: Gr91 [1] C R Brinkman, J P Strizak, M K Booker and V K Sikka, A Status Report on Exploratory Time-Dependent Fatigue Behavior of 2-1/4Cr-1 Mo and Modified Cr-1Mo Steel, ORNL/TM-7699, Oak Ridge National Laboratory, Oak Ridge, TN, June 1981 (Data from this report is provided in the Excel spreadsheet which includes testing from ORNL, MarTest, INL and GT for temperatures from 23 to 593°C.) [2] S D Antolovich, Fatigue Data Package for 9Cr-1Mo Steel, letter report to ORNL, Georgia Institute of Technology, Atlanta, Sept 1985 (Includes base metal, HAZ, welds with some short hold times, all 593°C, data included in the ORNL Excel compilation.) [3] M Ueda, M Tanigawa and Y Hara, Evaluation of Life Prediction Methods Using Published Creep-Fatigue Data, International Conference on Creep, pp 397-402, Japan Society of Mechanical Engineers, Tokyo, 1986 (Correlations for 600°C.) [4] C R Brinkman, J P Strizak and M K Booker, Smooth- and Notched-Bar Fatigue Characteristics of Modified 9Cr-1Mo Steel, ORNL-6330, Oak Ridge National Laboratory, Oak Ridge, TN Feb 1987 (Data from this report is provided in the Excel spreadsheet which includes testing from ORNL, MarTest, INL and GT for temperatures from 23 to 593°C.) [5] R W Swindeman, Cyclic Stress-Strain-Time Response of a 9Cr-1Mo-V-Nb Pressure Vessel Steel at High Temperature, Low Cycle Fatigue, STP 942, pp 107-122, American Society for Testing and Materials, Philadelphia, 1987 (Mostly 550°C.) [6] S Kitade, K Setoguchi, M Yamauchi and I Toshihide, Cyclic Stress-Strain Behavior of Modified 9Cr-1Mo Steel Under Creep-Fatigue, Mitsubishi Heavy Industries paper, (undated but last reference is 1988) [7] K Taguchi, E Kanno, S Ozaki and T Uno, Creep-Fatigue Evaluation Based on the Overstress Concept: A Coupling Method Between Unified Constitutive and Damage Equations, Structural Design for Elevated Temperature Environments- Creep, Ratchet, Fatigue, and Fracture, PVP Vol 163, pp 87-94, American Society of Mechanical Engineers, New York, 1989 (Focus is 550°C.) [8] Y Okamoto, M Yaguchi, A Ishikawa and Y Asada, Creep-Fatigue Analysis of 9Cr Steel Based on Overstress, SMIRT 11 Transactions, Vol L, pp 397-402, Tokyo, Aug 1991 (600°C correlations.) [9] H Kawasaki, Analytical Representation of Creep Properties of Mod 9Cr-1Mo Steel, paper presented at SMIRT, 1991 (550°C- good representation of cyclic relaxation procedure.) [10] D G O’Connor, Applicability of ASME Code Case N-47 Fatigue Life Reduction Factor to Modified 9Cr-1Mo Weldments, ORNL/9CR/92-1, Oak Ridge National Laboratory, Oak Ridge, TN, April 1992 54 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 (Some axial and torsional fatigue data on tubes at 538°C; no hold times.) [11] Y Asada, M Ueta, K Dousaki, M Sukekawa, K Taguchi and H Koto, Creep, Fatigue and Creep-Fatigue Properties of Modified 9Cr-1Mo Steel and Its Weldments for Steam Generator of Fast Breeder Reactor, Stress Classification, Robust Methods, and Elevated Temperature Design, PVP-Vol 230, pp 41-45, American Society of Mechanical Engineers, New York, 1992 (Focus is 600°C.) [12] Y Asada, T Nakamura, M Yaguchi, A Ishikawa and G Cao, Creep-Fatigue-Environment Interaction in Modified 9Cr-1Mo Steel, Stress Classification, Robust Methods, and Elevated Temperature Design, PVP-Vo 230, pp 47-52, American Society of Mechanical Engineers, New York, 1992 (Focus is 550°C.) [13] M Miyahara and K Tokimasa, Creep-Fatigue of Mod 9Cr-1Mo Steel Under Variable Straining, Pressure Vessel Technology, Volume Design, Analysis, Materials, pp 682-696, Verband der Technischen Überwachungs-Vereine e.V., Essen, Germany, 1992 (600°C strain range partitioning approach.) [14] T Sugiura, T Nakamura, A Ishikawa and Y Asada, Effect of Air on Creep-Fatigue Behavior of Some Commercial Steels, High-Temperature Service and Time Dependent Failure, PVP Vol 262, pp 139-145, American Society of Mechanical Engineers, New York, 1993 (600°C data.) [15] K Taguchi, M Ueta, K Dousaki, M Sukekawa, H Koto and Y Asada, Creep-Fatigue Life Prediction for Modified 9Cr-1Mo Steel High-Temperature Service and Time Dependent Failure, PVP Vol 262, pp 175-180, American Society of Mechanical Engineers, New York, 1993 (Similar to earlier papers- 550°C.) [16] Data Sheets on Elevated-Temperature, Time-Dependent Low-Cycle Fatigue Properties of ASTM A387 Grade 91 (9Cr-1Mo) Steel Plate for Pressure Vessels, NRIM Fatigue Data Sheet No 78, National Research Institute for Metals, Tokyo, 1993 (Includes 550°C to 650°C, slow-fast, relaxation holds, strain rate effects and provides cyclic S-e cuves and some relaxation curves for half life.) [17] K Aoto, R Komine, F Ueno, H Kawasaki and Y Wada, Creep-Fatigue [18] Evaluation of Normalized and Tempered Modified 9Cr-1Mo, Nuclear Engineering and Design, Vol 153, pp 97-110, 1994 (Focus is on 550°C Shows relaxation data to 100 hr in A-R and cyclic softened conditions.) [19] Y Asada and M Yaguchi, Mechanistic Approach for Creep-Fatigue Evaluation of 9Cr-1MoV-Nb Steel, Trans ASME, Vol 117, p 356, Oct 1995 [20] M Yaguchi, A Ishikawa and Y Asada, Study on a Non-Linear Damage Model for CreepFatigue Interaction, Service Experience, Structural Integrity, Severe Accidents, and Erosion in Nuclear and Fossil Plants, PVP-Vol 303, pp 223-228, American Society of Mechanical Engineers, New York, 1995 (Focus is 600°C.) 55 STP-PT-025 [21] Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range K Taguchi, M Ueta, H Koto and M Sukekawa, Creep-Damage Evaluation of Modified 9Cr-1Mo Steel Based on a Time-Fraction Concept, International Pressure Vessels and Piping Codes and Standards, Volume Current Perspectives, PVP-Vol 313-2, pp.449-457, American Society of Mechanical Engineers, New York 1995 (Focus is 550°C and 600°C Creep eq provided to calculate relaxation, cyclic hardening S-e curve, etc.) [22] K Tagauchi, S Maruyama, T Fujioka, Y Yamashita, H Koto, K Takahashi, Y Toya and T Sato, Creep, Fatigue, and Creep-Fatigue Properties of Modified 9Cr-1Mo Steel Weldments, Structural Integrity, NDE, Risk and Materials Performance for Petroleum, Process and Power, PVP Vol 336, pp 295-301, American Society of Mechanical Engineers, New York, 1996 (Most data for 550°C Some hold time effects Cyclic s-e curves.) [23] S Odaka, S Kato, E Yoshida, T Kawakami, T Suzuki, Y Takamori and S Kawashima, Material Test Data of 2.25Cr1Mo Steel and Mod 9Cr-1Mo Steel, JNC TN9450 2003-004, Japan Nuclear Cycle Development Institute, Japan, June 2003 (Includes strain rate effects data from 400°C to 520°C and hold time at 500°C and 600°C; no stresses reported.) [24] B Fournier, M Sauzay, M Mottot, H Brillet, I Monnet, and A Pineau, Experimentally Based Modelling of Cyclically Induced Softening in a Martensitic Steel at High Temperatures, Creep and Fracture in High Temperature Components, Proceedings of the ECCC Creep Conference, pp 649-661, London, Sept 12-14, 2005 (Focus is on cyclic softening at 550°C.) [25] M-T Cabrillat, L Allais, M Mottot, B Riou and C Escaravage, Creep Fatigue Behavior and Damage Assessment for Mod Cr 1Mo Steel, paper PVP2006-ICPVT11-93238, Proceedings of PVP2006-ICPVT-11, Vancouver, BC, July 23-27, 2006 (Provides, stress, strain and hold-time life data for 550°C.) [26] Y Takahashi, Accuracy and Margin in Creep-Fatigue Evaluation for Modified 9Cr-1Mo Steel, paper PVP2007-26695, Proceedings of PVP2007-Creep 8, San Antonio, TX, July 2226, 2007 (Data for 550°C, 600°C, and 650°C, calculated relaxation for half life, proposes modified ductility exhaustion) [27] A Scholz and C Berger, Improved Methods of Creep-Fatigue Life Assessment of Components, paper B5-07 presented at the Fifth International Conference on Advances in Materials Technology for Fossil Power Plants, Marco Island, FL, October 3-5, 2007 (Introduces a constitutive model that covers cyclic deformation and relaxation from 450 to 625°C.) 56 Extend Fatigue Exemption Rules for Low Cr Alloys into the Time-Dependent Range STP-PT-025 ACKNOWLEDGMENTS The authors acknowledge, with deep appreciation, the following individuals for their technical contributions to this document: • Bob Swindeman • Ben Hantz • Rich Basil The authors further acknowledge, with deep appreciation, the activities of ASME staff and volunteers who have provided valuable technical input, advice and assistance with review of, commenting on, and editing of, this document 57 A18909