Application of Code Case 2605 for Fatigue Evaluation of Vessels Made in 2.25Cr-1Mo-0.25V Steels Slightly Into Creep Range

2013 ◽  
Vol 135 (4) ◽  
Author(s):  
Susumu Tereda
Keyword(s):  
Screening Method ◽  
Fatigue Analysis ◽  
Allowable Stress ◽  
Sample Analysis ◽  
Inelastic Analysis ◽  
Asme Code ◽  
Section Viii ◽  
Fatigue Evaluation ◽  
Division 2 ◽  
Made In

The current Section VIII Division 2 of ASME code permits only the method based on experience with comparable equipment of paragraph 5.5.2.2 to be used for the exemption from fatigue analysis when the design allowable stress is taken in the time dependent temperature range and the specified minimum tensile strength is greater than 552 MPa. In the case of 2.25Cr-1Mo-0.25V steels, the allowable stress of new Div.2 is higher than that of the old Div.2. Therefore, there are no experiences with comparable equipment. Code Case 2605-1 provides rules for fatigue evaluation of 2.25Cr-1Mo-0.25V steels at temperatures greater than 371 °C and equal to or less than 454 °C. An inelastic analysis including the effect of creep is required to be performed for all pressure parts according to Code Case 2605-1. There are six and more types of nozzles in each hydro-processing reactor. The inelastic analyses shall be performed for all types of nozzles. The simplified screening method for fatigue analyses and the simplified fatigue analysis procedure need to be developed because it takes much time to perform inelastic analyses. This paper provides sample analysis results for various types of nozzles and clarifies issue with respect to implementation of Code Case 2605-1. Then, a proposal for simplification and modification of Option 1 and Option 2 fatigue evaluation methods for nozzles of Code Case 2605-1 are proposed from these investigations.

Applications of Code Case 2605 for Fatigue Evaluation of Vessels Made in 2.25Cr-1Mo-0.25V Steels Slightly Into Creep Range

2010 ◽  
Author(s):  
Susumu Terada
Keyword(s):  
Fatigue Curve ◽  
Time Dependent ◽  
Inelastic Analysis ◽  
Asme Code ◽  
Section Viii ◽  
Preliminary Study ◽  
Number Of Cycles ◽  
Fatigue Evaluation ◽  
Division 2 ◽  
Made In

The current Section VIII Division 2 of ASME code does not permit method A of paragraph 5.5.2.3 to be used for the exemption from fatigue analysis when the design allowable stress is taken in the time dependent temperature range. Method B of paragraph 5.5.2.4 also cannot be used because it requires the use of the fatigue curve which is limited to 371 ° C and below the needed temperature. Code Case 2605 is a rule for fatigue evaluation of 2.25Cr-1Mo-0.25V steels at temperatures greater than 371 ° C and less than 454 ° C. An inelastic analysis including the effect of creep shall be performed for all pressure parts according to Code Case 2605. Especially, a full inelastic analysis shall be performed using the actual time-dependent thermal and mechanical loading histograms for the lateral nozzle based on preliminary study. It takes much time to perform this inelastic analysis for all full histograms and obtain the fatigue evaluation results when large number of cycles of full pressure is specified in user’s design specification. This paper provides sample analysis results for nozzles and clarifies issue of implementation of Code Case 2605. Then, the proposal of simplification and modification of Code Case 2605 from these results are proposed.

Proposed Code Case of Creep Fatigue Evaluation of 9Cr-1Mo-V Steels for High Pressure Vessels in ASME Section VIII Division 2

2015 ◽  
Author(s):  
Susumu Terada ◽  
Masato Yamada ◽  
Tomoaki Nakanishi
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Fatigue Curve ◽  
Pressure Vessels ◽  
Inelastic Analysis ◽  
Creep Fatigue ◽  
Asme Code ◽  
Section Viii ◽  
Fatigue Evaluation ◽  
Division 2

9Cr-1Mo-V steels (Gr. 91), which has an excellent performance at high temperature in mechanical properties and hydrogen resistance, has been used for tubing and piping materials in power industries and it can be a candidate material for high pressure vessels for high temperature processes in refining industries. The current Section VIII Division 2 of ASME code does not permit method A of paragraph 5.5.2.3 to be used for the exemption from fatigue analysis for Gr. 91 steels due to limitation of specified minimum tensile strength (585 MPa > 552 MPa). Method B of paragraph 5.5.2.4 also can’t be used because it requires the use of the fatigue curve which is limited to 371 °C lower than the needed temperature. Therefore new rules for fatigue evaluation of Gr. 91 steels at temperatures greater than 371 °C and less than 500 °C similar to CC 2605 for 2.25Cr-1Mo-0.25V(Gr. 22V) steels are necessary. This paper provides fatigue test results at 500 °C for Gr. 91 steels, the modification of CC 2605, sample inelastic analysis results for nozzles. Then, the new Code Case for Gr. 91 steels is proposed from these results.

User’s Design Specification Preparation for 2¼Cr-1Mo-¼V Reactors in Accordance With ASME Section VIII, Division 2 Code and Code Case 2605

2013 ◽  
Author(s):  
Radoslav Stefanovic ◽  
Alicia Avery ◽  
Kanhaiya Bardia ◽  
Reza Kabganian ◽  
Vasile Oprea ◽  
...  
Keyword(s):  
Operating Temperature ◽  
Design Specification ◽  
Element Analysis ◽  
Analysis And Evaluation ◽  
Reheat Cracking ◽  
Inelastic Analysis ◽  
Allowable Stresses ◽  
Section Viii ◽  
Fatigue Evaluation ◽  
Division 2

Today’s hydroprocessing reactor manufacturers use 2¼Cr–1Mo–¼V steel to build lighter reactors than conventional Cr-Mo reactors. Manufacturing even lighter hydroprocessing reactors has been enabled with the introduction of the new ASME Section VIII Division 2 Code, initially released in 2007. The higher allowable stresses in the new Division 2 for these Vanadium-modified steels permits even lighter reactors to be built while maintaining suitable design margins. The new Division 2 Code requires additional engineering to ensure safe design. One of the challenges the engineer is faced with, is preparation of the User’s Design Specification (UDS) including new and more stringent requirements for fatigue evaluation. As the operating temperature of the rector is higher than 371°C, engineers have to evaluate the fatigue life of the reactor in accordance with Code Case 2605 (CC2605). CC2605 requires inelastic analysis and evaluation effects of creep. Vanadium-modified reactors require additional care during fabrication to prevent higher hardness around weld areas, reheat cracking, and reduced toughness at lower temperatures in the “as welded” condition. This paper provide guidance for the preparation of an ASME Section VIII Division 2 User’s Design Specification including process descriptions of all the cycles expected for the life of the rector and analysis requested by CC2605. An example of such an analysis, including finite element analysis results, is provided in this paper. Requirements to provide the material specification is also discussed with an emphasis on prevention of reheat cracking, hardenability, and temper and hydrogen embitterment.

Method B Fatigue Screening in ASME BPV Code, Section VIII, Division 2, Part 5

2019 ◽  
Author(s):  
Kenneth Kirkpatrick ◽  
Christopher R. Johnson ◽  
J. Adin Mann
Keyword(s):  
Fatigue Damage ◽  
Pressure Vessel ◽  
Fatigue Analysis ◽  
Damage Factor ◽  
Simple Method ◽  
Mechanical Loads ◽  
Penalty Factor ◽  
Section Viii ◽  
Cyclic Service ◽  
Division 2

Abstract ASME Boiler and Pressure Vessel Code (BPVC), Section VIII, Division 2, Part 5 Method B fatigue screening is intended to be a quick and simple method that is sufficiently conservative to screen components in cyclic service thus not requiring detailed fatigue analysis. The method assesses pressure, thermal, and mechanical loads separately. The basis for each portion of the method is discussed along with an alternative bases for the assessments. Each assessment is reformulated as a fatigue damage factor and all variables are provided so that the intent of each equation is clearly identifiable. A penalty factor will be included in each equation rather than assuming one penalty for all designs, the reformulation creates penalty for non-fatigue resistant designs and reduces the penalty for fatigue resistant designs. Examples are given showing the potentially non-conservative results if a summed damage is not used.

Evaluation of ASME Pressure Vessel Code Prohibitions on Rod and Bar Stock and Potential Remedies

2014 ◽  
Author(s):  
John J. Aumuller ◽  
Vincent A. Carucci
Keyword(s):  
Pressure Vessels ◽  
Early 20Th Century ◽  
Economic Disadvantage ◽  
User Experiences ◽  
The Public ◽  
Division 1 ◽  
Asme Code ◽  
Billet Material ◽  
Section Viii ◽  
Division 2

The ASME Codes and referenced standards provide industry and the public the necessary rules and guidance for the design, fabrication, inspection and pressure testing of pressure equipment. Codes and standards evolve as the underlying technologies, analytical capabilities, materials and joining methods or experiences of designers improve; sometimes competitive pressures may be a consideration. As an illustration, the design margin for unfired pressure vessels has decreased from 5:1 in the earliest ASME Code edition of the early 20th century to the present day margin of 3.5:1 in Section VIII Division 1. Design by analysis methods allow designers to use a 2.4:1 margin for Section VIII Division 2 pressure vessels. Code prohibitions are meant to prevent unsafe use of materials, design methods or fabrication details. Codes also allow the use of designs that have proven themselves in service in so much as they are consistent with mandatory requirements and prohibitions of the Codes. The Codes advise users that not all aspects of construction activities are addressed and these should not be considered prohibited. Where prohibitions are specified, it may not be readily apparent why these prohibitions are specified. The use of “forged bar stock” is an example where use in pressure vessels and for certain components is prohibited by Codes and standards. This paper examines the possible motive for applying this prohibition and whether there is continued technical merit in this prohibition, as presently defined. A potential reason for relaxing this prohibition is that current manufacturing quality and inspection methods may render a general prohibition overly conservative. A recommendation is made to better define the prohibition using a more measurable approach so that higher quality forged billets may be used for a wider range and size of pressure components. Jurisdictions with a regulatory authority may find that the authority is rigorous and literal in applying Code provisions and prohibitions can be particularly difficult to accept when the underlying engineering principles are opaque. This puts designers and users in these jurisdictions at a technical and economic disadvantage. This paper reviews the possible engineering considerations motivating these Code and standard prohibitions and proposes modifications to allow wider Code use of “high quality” forged billet material to reflect some user experiences.

A Comparison of Different Design Codes on Fatigue Life Assessment Methods

2016 ◽  
Author(s):  
Jinhua Shi ◽  
Liwu Wei ◽  
Claude Faidy ◽  
Andrew Wasylyk ◽  
Nawal Prinja
Keyword(s):  
Pressure Vessel ◽  
Task Force ◽  
Fatigue Analysis ◽  
Life Assessment ◽  
Design Codes ◽  
Fatigue Life Assessment ◽  
Analysis Methods ◽  
Section Viii ◽  
Division 2 ◽  
Nuclear Association

Different pressure vessel and piping design codes and standards have adopted different fatigue analysis methods. In order to make some contribution to current efforts to harmonize international design codes and standards, a review of fatigue analysis methods for a number of selected nuclear and non-nuclear design codes and standards has been carried out. The selected design codes and standards are ASME Boiler and Pressure Vessel Code Section III Subsection NB and Section VIII Division 2, EN 12952, EN 13445, EN 13480, PD 5500, RCC-M, RCC-MRx, JSME, PNAEG and R5. This paper presents the initial review results. The results of the study could be used as part of the on-going work of the Codes and Standards Task Force of the World Nuclear Association (WNA) Cooperation in Reactor Design Evaluation and Licensing (CORDEL) Working Group.

Stress Classification Using the R-Node Method

2006 ◽  
Author(s):  
Ihab F. Z. Fanous ◽  
R. Seshadri
Keyword(s):  
Experimental Data ◽  
Complex Geometries ◽  
Element Analysis ◽  
Shell Elements ◽  
Linear Elastic ◽  
Stress Classification ◽  
Wide Range ◽  
Asme Code ◽  
Section Viii ◽  
Division 2

The ASME Code Section III and Section VIII (Division 2) provide stress classification guidelines to interpret the results of a linear elastic finite element analysis. These guidelines enable the splitting of the generated stresses into primary, secondary and peak. The code gives some examples to explain the suggested procedures. Although these examples may reflect a wide range of applications in the field of pressure vessel and piping, the guidelines are difficult to use with complex geometries. In this paper, the r-node method is used to investigate the primary stresses and their locations in both simple and complex geometries. The method is verified using the plane beam and axisymmetric torispherical head. Also, the method is applied to analyze 3D straight and oblique nozzle modeled using both solid and shell elements. The results of the analysis of the oblique nozzle are compared with recently published experimental data.

Code Case for Extension Use of 2-1/4Cr-1Mo-1/4V Steels for Vessels in ASME Section VIII Division 3

2006 ◽  
Author(s):  
Susumu Terada
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Yield Strength ◽  
Allowable Stress ◽  
Section Viii ◽  
Division 2

2-1/4Cr-1Mo-1/4V steels have been used extensively as materials for reactors in high temperature and high pressure hydrogeneration service. The design temperature of these reactors is 850F to 900F. These reactors have been designed per ASME Sec. VIII Division 2. If these reactors can be designed per ASME Sec. VIII Division 3, thickness of shell and head for these reactors in case of design temperature of 850F can be reduced by about 15% compared with that per Division 2 even if the membrane abjustment factors based on creep allowable stress are applied. However yield strength in Division 3 is limited less than 700F. In this paper, the additional requirements and background for extension use of 2-1/4Cr-1Mo-1/4V steels are presented.

Improved Construction of Multilayer Vessels to Apply the ASME Code Section VIII, Division 2

1975 ◽  
Vol 97 (1) ◽  
pp. 14-21
Author(s):  
T. Yamauchi
Keyword(s):  
Thermal Conductivity ◽  
Stress Analysis ◽  
Test Piece ◽  
Solid Wall ◽  
Nondestructive Inspection ◽  
Construction Method ◽  
Asme Code ◽  
Welding Part ◽  
Section Viii ◽  
Division 2

It has been made possible to design the multilayered vessel by employing stress analysis according to ASME Section VIII, Division 2, using the construction method of reinforcing the flexual rigidity at the discontinuous part, and assuring the shell thermal conductivity to some fraction of the solid wall shell. Nondestructive inspection for the welding part has been tested to improve the construction method by the test piece.

Modification and Extension of Screening Criteria for Fatigue Analysis

2019 ◽  
Vol 142 (1) ◽  
Author(s):  
Jun Shen ◽  
Mingwan Lu ◽  
Zhenyu Wang ◽  
Heng Peng ◽  
Yinghua Liu
Keyword(s):  
Fatigue Curve ◽  
Fatigue Analysis ◽  
Allowable Stress ◽  
Design Factor ◽  
Screening Criteria ◽  
Asme Code ◽  
Applicable Range ◽  
Number Of Cycles ◽  
Design Pressure

Abstract ASME Code VIII-2-2019 and previous versions provided three screening criteria for fatigue analysis. From edition 2004 to 2019, the design factor for material allowable stress decreased and the considered range of permissible cyclic number for design fatigue curve extended. However, screening criteria are almost unchanged except one restriction: If the specified number of cycles is greater than 106, then the screening criteria are not applicable and a fatigue analysis is required. In this paper, percentage limit of the design pressure in method A is modified and the specified number of cycles is extended. Some revision suggestions are also proposed to broaden the applicable range of the screening criterion.

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