Printed on 18 November, 2003
CAESAR II Technical Reference Manual
Copyright © 1993-2004 COADE, Inc. All Rights Reserved.
Contents
Chapter 1: Introduction
1
Overview ...2
Program Support / User Assistance ...3
COADE Technical Support ...4
Chapter 2: Configuration and Environment
1
Generation of the CAESAR II Configuration File...2Computation Control ...3
Use Pressure Stiffening ...3
Missing Mass ZPA ...3
Bend Axial Shape ...3
Rod Tolerance (degrees)...4
Rod Increment (degrees) ...4
Alpha Tolerance ...4
Ambient Temperature...4
Friction Stiffness ...4
Friction Normal Force Variation ...5
Friction Angle Variation...5
Friction Slide Multiplier ...5
Coefficient of Friction (Mu) ...5
WRC-107 Version ...5
WRC-107 Interpolation Method...5
Incore Numerical Check...5
Decomposition Singularity Tolerance ...6
Minimum Wall Mill Tolerance (%)...6
Bourdon Pressure...7
Ignore Spring Hanger Stiffness ...7
Include Spring Stiffness in Hanger OPE Travel Cases...7
Hanger Default Restraint Stiffness ...8
Default Translational Restraint Stiffness...8
Default Rotational Restraint Stiffness ...8
SIFs and Stresses ...9
Default Code...9
Occasional Load Factor ...10
Yield Stress Criterion ...11
B31.3 Sustained Case SIF Factor ...12
B31.3 Welding and Contour Insert Tees Meet B16.9...13
Allow User's SIF at Bend ...13
Use WRC329...13
Use Schneider...13
All Cases Corroded...13
Liberal Expansion Stress Allowable...14
WRC 329...14
Base Hoop Stress On ( ID/OD/Mean/Lamés )...14
Add F/A in Stresses ...14
Add Torsion in SL Stress...15
Stress Stiffening Due to Pressure ...15
Reduced Intersection ...16
Class 1 Branch Flexibility ...17
B31.1 Reduced Z Fix...17
Schneider ...17
No RFT/WLT in Reduced Fitting SIFs ...17
Apply B31.8 Note 2...17
Pressure Variation in Expansion Cases ...17
Geometry Directives ...18
Connect Geometry Through Cnodes ...18
Auto Node Number Increment ...18
Z-Axis Vertical...19
Minimum Allowed Bend Angle ...19
Maximum Allowed Bend Angle...19
Bend Length Attachment Percent...19
Minimum Angle to Adjacent Bend...19
Loop Closure Tolerance ...19
Horizontal Thermal Bowing Tolerance ...20
Plot Colors ...21 OPENGL Switch ...21 Pipes ...21 Nodes...21 Rigids/Bends...21 Hangers/Nozzles...22 Structure ...22 Background...22 Axes...22 Labels ...22 Highlights ...22 Displaced Shape ...22 Stress Level 1 ...22 Stress Level 2 ...22 Stress Level 3 ...22 Stress Level 4 ...22 Stress Level 5 ...22 Stress < Level 1 ...23 Stress > Level 1 ...23 Stress > Level 2 ...23 Stress > Level 3 ...23 Stress > Level 4 ...23 Stress > Level 5 ...23 FRP Pipe Properties...24 Use FRP SIF ...24 Use FRP Flexibilities...24
FRP Property Data File...25
BS 7159 Pressure Stiffening...25
FRP Laminate Type...25
Exclude f2 from UKOOA Bending Stress...26
FRP Pipe Density ...26
FRP Alpha (e-06) ...26
FRP Modulus of Elasticity ...26
Ratio Shear Mod:Emod ...26
Database Definitions...27
Structural Database...27
Piping Size Specification (ANSI/JIS/DIN/BS)...27
Valves and Flanges...27
Expansion Joints...28
Units File Name...28
Load Case Template ...28
System Directory Name...28
Default Spring Hanger Table...28
Enable Data Export to ODBC-Compliant Databases ...28
Append Reruns to Existing Data ...29
ODBC Compliant Database Name ...29
Miscellaneous ...30
Output Table of Contents ...30
Output Reports by Load Case...30
Displacement Reports Sorted by Nodes ...30
Time History Animation...31
Dynamic Example Input Text...31
Memory Allocated...31
User ID ...31
Disable "File Open" Graphic Thumbnail...31
Disable Undo/Redo Ability ...32
Enable Autosave ...32
Autosave Time Interval ...32
Prompted Autosave ...32
Set/Change Password...33
Access Protected Data ...33
New Password ...33
Change Password...33
Remove Password ...33
Units File Operations ...34
Make Units File ...34
Review Existing Units File...34
Create a New Units File...35
Existing File to Start From ...36
New Units File Name ...36
View/Edit File ...36
Convert Input to New Units...37
Name of the Input File to Convert...37
Name of the Units File to Use ...37
Name of the Converted File...37
Material Database ...38
Material - Add ...38
Material - Delete...38
Material - Edit...39
Chapter 3: Piping Screen Reference
1
Piping Spreadsheet Data ...2Help Screens and Units...2
Auxiliary Fields - Component Information ...14
Bends ...14
Rigid Elements ...18
Reducers ...20
SIFs & Tees ...22
Auxiliary Fields - Boundary Conditions...31
Restraints ...31
Hangers...36
Nozzles ...48
Nozzle Flexibility - WRC 297...48
Displacements...57
Auxiliary Fields - Imposed Loads...58
Forces and Moments...58
Uniform Loads...58
Wind Loads ...59
Wave Loads ...60
Auxiliary Fields - Piping Code Data...62
Allowable Stresses...62 Available Commands...79 Break Command ...79 Valve/Flange Database ...81 Find Distance...84 Find Element ...84 Global Coordinates...85 Insert Element...85 Node Increment ...85
Show Informational Messages...85
Tee SIF Scratchpad...85
Bend SIF Scratchpad ...91
Expansion Joint Modeler ...95
Expansion Joint Modeler Notes...98
Expansion Joint Design Notes ...99
Torsional Spring Rates ...99
Bellows Application Notes...100
Available Expansion Joint End-Types...100
Pressure Rating...101
Expansion Joint Styles...101
Materials...102
Title Page...103
Hanger Data...103
Special Execution Parameters...109
Combining Independent Piping Systems...119
List/ Edit Facility...121
Block Operations ...123
Printing an Input Listing...126
Input Plotting ...127
Model Rotation, Panning, and Zooming...127
Views...129
Volume Plotting...129
Piping Input Graphics ...131
Static Output Graphics...134
Chapter 4: Structural Steel Modeler
1
Overview ...2The Structural Steel Property Editor...3
New File ...3
Units File ...4
Vertical Axis...5
Material Properties ...6
Cross Section (Section ID) ...7
Model Definition Method...10
General Properties...12
Add ...12
Insert...12
Replace ...12
Delete...12
UNITS Specification - UNIT...13
Axis Orientation Vertical...14
Material Identification - MATID ...15
MATID...15 YM...15 POIS ...16 G ...16 YS...16 DENS...16 ALPHA...16
Section Identification - SECID ...17
Section ID...17
SECID ...17
Name ...18
Setting Defaults - DEFAULT ...19
Setting Nodes in Space - NODE, NFILL, NGEN...20
NODE...20
NFILL...21
NGEN...22
Building Elements - ELEM, EFILL, EGEN, EDIM...24
ELEM ...24
EFILL ...25
EGEN ...27
EDIM...29
Resetting Element Strong Axis - ANGLE, ORIENT...32
ANGLE ...32
ORIENT ...33
End Connection Information...35
Free End Connections - FREE...35
Standard Structural Element Connections - BEAMS, BRACES, COLUMNS ...38
BRACES ...40
COLUMNS ...42
Defining Global Restraints - FIX ...44
Loads ...46
Point Loads - LOAD...46
Gravity Loads - GLOADS...50
Wind Loads - WIND ...51
Utilities ...53 LIST...53 Structural Databases ...54 AISC 1977 Database ...55 AISC 1989 Database ...61 German 1991 Database...68 Australian 1990 Database...71
South African 1992 Database ...73
Korean 1990 Database...74
UK 1993 Database...75
Chapter 5: Controlling the Dynamic Solution
1
Dynamic Analysis Input ...2Dynamic Analysis Overview ...3
Random ...3
Harmonic ...3
Impulse ...6
Harmonic Analysis ...8
Excitation Frequencies ...8
Harmonic Forces and Displacements ...11
Harmonic Displacements...13
Response Spectra / Time History Load Profiles ...16
Response Spectrum / Time History Profile Data Point Input ...21
Force Response Spectrum Definitions...22
Building Spectrum / Time History Load Cases ...24
Spectrum /Time History Profile...24
Factor...24
Direction...25
Combining Static and Dynamic Results ...32
Spectrum Time History...38
Force...38 Direction...38 Node ...38 Force Set #...38 Lumped Masses ...44 Mass...44 Direction...44 Start Node...44 Stop Node ...45 Increment...45 Snubbers ...46
Dynamic Control Parameters...48
Analysis Type (Harmonic/Spectrum/Modes/Time-History) ...49
Static Load Case for Nonlinear Restraint Status...62
Stiffness Factor for Friction (0.0 - Not Used)...63
Max. No. of Eigenvalues Calculated (0-Not used) ...64
Frequency Cutoff (HZ)...67
Closely Spaced Mode Criteria/Time History Time Step (ms) ...68
Load Duration (Time History or DSRSS Method) (Sec.)...69
Damping (Time History or DSRSS) (Ratio of Critical) ...69
Re-use Last Eigensolution ...73
Spatial or Modal Combination First ...73
Spatial Combination Method (SRSS/ABS) ...74
Modal Combination Method (GROUP/10%/DSRSS/ABS/SRSS)...74
Include Pseudostatic (Anchor Movement) Components (Y/N)...77
Include Missing Mass Components (Y/N) ...78
Pseudostatic (Anchor Movement) Comb. Method (SRSS/ABS)...78
Missing Mass Combination Method (SRSS/ABS) ...78
Directional Combination Method (SRSS/ABS) ...79
Sturm Sequence Check on Computed Eigenvalues (Y/N)...79
Advanced Parameters ...81
Estimated Number of Significant Figures in Eigenvalues ...81
Jacobi Sweep Tolerance ...82
Decomposition Singularity Tolerance ...82
Subspace Size (0-Not Used) ...82
No. to Converge Before Shift Allowed (0 - Not Used) ...83
No. of Iterations Per Shift (0 - Pgm computed) ...83
Percent of Iterations Per Shift Before Orthogonalization ...84
Force Orthogonalization After Convergence (Y/N) ...84
Use Out-Of-Core Eigensolver (Y/N)...84
Frequency Array Spaces...84
Pulsation Loads...85
Relief Valve Thrust Load Analysis...88
Relief Load Synthesis for Gases Greater Than 15 psig ...88
Relief Load Synthesis for Liquids ...94
Output From the Liquid Relief Load Synthesizer...96
Chapter 6: Technical Discussions
1
Rigid Element Application ...2Rigid Material Weight ...2
Rigid Fluid Weight ...2
Rigid Insulation Weight...2
Cold Spring...4
Expansion Joints ...7
Hanger Sizing Algorithm...10
Spring Design Requirements ...10
Restrained Weight Case...10
Operating Case ...11
Installed Load Case ...11
Setting Up the Spring Load Cases ...12
Constant Effort Support...12
Including the Spring Hanger Stiffness in the Design Algorithm ...13
Other Notes on Hanger Sizing...13
Class 1 Branch Flexibilities ...14
Modeling Friction Effects...17
Nonlinear Code Compliance...19
Sustained Stresses and Nonlinear Restraints ...20
Notes on Occasional Load Cases...23
Static Seismic Loads...24
Wind Loads...27
Elevation...29
Hydrodynamic (Wave and Current) Loading ...30
Applicable Wave Theory Determination...32
Pseudo-Static Hydrodynamic Loading ...32
AIRY Wave Theory Implementation ...33
STOKES Wave Theory Implementation ...34
Stream Function Wave Theory Implementation...34
Ocean Currents ...34
Technical Notes on CAESAR II Hydrodynamic Loading...35
Input: Specifying Hydrodynamic Parameters in CAESAR II ...39
Current Data ...39
Wave Data ...41
Seawater Data...42
Piping Element Data...42
References ...42
Evaluating Vessel Stresses...44
ASME Section VIII Division 2 - Elastic Analysis of Nozzle ...44
Procedure to Perform Elastic Analyses of Nozzles ...46
Description of Alternate Simplified ASME Sect. VIII Div. 2 Nozzle Analysis...47
Simplified ASME Sect. VIII Div. 2 Elastic Nozzle Analysis...48
Inclusion of Missing Mass Correction...49
References ...52
Fatigue Analysis Using CAESAR II...54
Fatigue Basics...54
Fatigue Analysis of Piping Systems ...55
Static Analysis Fatigue Example ...56
Fatigue Capabilities in Dynamic Analysis...65
Creating the .FAT Files ...67
Calculation of Fatigue Stresses...68
Pipe Stress Analysis of FRP Piping ...70
Underlying Theory ...70
FRP Analysis Using CAESAR II ...85
Code Compliance Considerations...93
General Notes for All Codes ...93
Code-Specific Notes ...98
Local Coordinates ...127
Other Global Coordinate Systems ...128
The Right Hand Rule...128
Pipe Stress Analysis Coordinate Systems...130
Defining a Model...133
Using Local Coordinates ...135
CAESAR II Local Coordinate Definitions ...136
Applications - Utilizing Global and Local Coordinates...140
Transforming from Global to Local ...146
Frequently Asked Questions...147
Chapter 7: Miscellaneous Processors
1
Accounting...2Batch Stream Processing ...9
CAESAR II Fatal Error Processing ...11
Chapter 8: Interfaces
1
Overview of CAESAR II Interfaces ...2CAD Interfaces ...4 CADWorx/PIPE Link...4 DXF AutoCAD Interface...4 CADPIPE Interface ...5 ComputerVision Interface ...24 Intergraph Interface ...26 PRO-ISO Interface ...64 PCF Interface...72
Generic Neutral Files ...74
CAESAR II Neutral File Interface ...74
Data Matrix Interface...94
Computational Interfaces...95
LIQT Interface...95
PIPENET Interface...100
Data Export to ODBC Compliant Databases ...102
DSN Setup ...102
Controlling the Data Export ...105
Data Export Wizard...106
Chapter 9: File Sets
1
CAESAR II File Guide ...2CAESAR II Operational (Job) Data Files...14
Chapter 10: Update History
1
CAESAR II Initial Capabilities (12/84)...2CAESAR II Version 1.1S Features (2/86) ...3
CAESAR II Version 2.0A Features (10/86) ...4
CAESAR II Version 2.1C Features (6/87)...5
CAESAR II Version 2.2B Features (9/88)...6
CAESAR II Version 3.0 Features (4/90) ...7
CAESAR II Version 3.1 Features (11/90) ...8
Graphics Updates...8
Rotating Equipment Report Updates ...8
WRC 107 Updates...8
Miscellaneous Modifications...8
CAESAR II Version 3.15 Features (9/91) ...9
Flange Leakage and Stress Calculations...9
WRC 297 Local Stress Calculations...9
Stress Intensification Factor Scratchpad...9
Miscellaneous ...9
CAESAR II Version 3.16 Features (12/91) ...10
CAESAR II Version 3.17 Features (3/92) ...11
CAESAR II Version 3.18 Features (9/92) ...12
Interfaces Added...12
Miscellaneous Changes ...12
CAESAR II Version 3.19 Features (3/93) ...14
CAESAR II Version 3.20 Features (10/93) ...15
CAESAR II Version 3.21 Changes and Enhancements (7/94) ...16
CAESAR II Version 3.22 Changes & Enhancements (4/95)...18
CAESAR II Version 3.23 Changes (3/96) ...20
CAESAR II Version 3.24 Changes & Enhancements (3/97)...21
CAESAR II Version 4.00 Changes and Enhancements (1/98) ...24
CAESAR II Version 4.10 Changes and Enhancements (1/99) ...25
CAESAR II Version 4.20 Changes and Enhancements (2/00) ...26
CAESAR II Version 4.30 Changes and Enhancements (3/01) ...27
CAESAR II Version 4.40 Features...28
In This Chapter
Overview...2 Program Support / User Assistance ...3 COADE Technical Support...4
C
H A P T E R
1
Overview
This CAESAR II Technical Reference Guide is the reference manual for CAESAR II. It presents the theory behind CAESAR II operations, and explains why certain tasks are performed. Users are urged to review the background material contained in this manual, especially when applying CAESAR II to unfamiliar types of analysis.
Chapter 2 (see "Configuration and Environment" on page 1) discusses the configuration of CAESAR II and
the resulting environment. This includes language support and program customization. In addition to the COADE supplied routines, several third-party diagnostic packages are also mentioned.
Chapter 3 (see "Piping Screen Reference" on page 1), Piping Input Reference, contains images of program
generated screens, and explains each input cell, menu option, and toolbar button. Also discussed in detail is the Plot Screen, which displays the input model graphically.
Chapter 4 (see "Structural Steel Modeler" on page 1) examines the Structural Steel Modeler and describes
all commands, toolbar buttons, menu items, and input fields.
Chapter 5 (see "Controlling the Dynamic Solution" on page 1) discusses the Dynamic Input and Control
Parameters: each input cell, toolbar button, and menu item is examined. The purpose and effects of the various Dynamic Control Parameters are detailed.
Chapter 6 (see "Technical Discussions" on page 1) contains theoretical overviews of various technical
methods used in CAESAR II. Both common and advanced modeling techniques are covered.
Chapter 7 (see "Miscellaneous Processors" on page 1) provides information regarding a few
miscellaneous auxiliary processors.
Chapter 8 (see "Interfaces" on page 1) details interfaces between CAESAR II and other programs. Chapter 9 (see "File Sets" on page 1) presents a list of files associated with CAESAR II.
Program Support / User Assistance
COADE’s staff understands that CAESAR II is not only a complex analysis tool but also, at times, an elaborate process—one that may not be obvious to the casual user. While our documentation is intended to address the questions raised regarding piping analysis, system modeling, and results interpretation, not all the answers can be quickly found in these volumes.
COADE understands the engineer’s need to produce efficient, economical, and expeditious designs. To that end, COADE has a staff of helpful professionals ready to address any CAESAR II and piping issues raised by users. CAESAR II support is available by telephone, e-mail, fax, and the internet; literally hundreds of support calls are answered every week. COADE provides this service at no additional charge to the user. It is expected, however, that questions focus on the current version of the program.
Formal training in CAESAR II and pipe stress analysis is also available from COADE. COADE schedules regular training classes in Houston and provides in-house and open attendance training around the world. These courses focus on the expertise available at COADE — modeling, analysis, and design.
COADE Technical Support
Phone: 281-890-4566 E-mail: [email protected]
Fax: 281-890-3301 WEB: www.coade.com
(http://www.coade.com/c2articles/c2_faq_ web.html)
In This Chapter
Generation of the CAESAR II Configuration File ...2
Computation Control...3
SIFs and Stresses...9
Geometry Directives...18 Plot Colors...21 FRP Pipe Properties ...24 Database Definitions ...27 Miscellaneous...30 Set/Change Password ...33
Units File Operations ...34
Convert Input to New Units ...37
Material Database...38
C
H A P T E R
2
Generation of the CAESAR II Configuration File
Each time CAESAR II starts, the configuration file caesar.cfg is read from the current data directory. If this file is not found in the current data directory, the installation directory is searched for the configuration file. If the configuration file is not found, a fatal error will be generated and CAESAR II will terminate. The configuration or setup file contains directives that dictate how CAESAR II will operate on a particular computer and how it will perform a particular analysis. The caesar.cfg file is generated by selecting
TOOLS/CONFIGURE/SETUP (or the Configure button from the toolbar) from the CAESAR II Main Menu.
Note: You must click the Exit w/Save button on the bottom of the Configure/Setup window to create a new configuration file or to save changes to the existing configuration file. The configuration program produces the Computation Control (on page 3) window. Use the tabs to navigate to the appropriate
configuration spreadsheets.
Important: The caesar.cfg file may vary from machine to machine and many of the setup directives
modify the analysis. Do not expect the same input file to produce identical results between machines unless the setup files are identical. It is advised that a copy of the setup file be archived with input and output data so that identical reruns can be made. The units file, if modified by the user, would also need to be identical if the same results are to be produced.
The following section explains the CAESAR II setup file options. They are grouped as they appear when chosen from the tabs on the Configure window.
Computation Control
Computational Control Configuration Settings
Use Pressure Stiffening
This flag enables CAESAR II to include pressure-stiffening effects in those codes that do not explicitly require its use. In these cases pressure-stiffening effects will apply to all bends, elbows, and both miter types. In all cases, the pressure used is the maximum of all pressures defined for the element.
Missing Mass ZPA
The default for this option is Extracted, which means that CAESAR II will use the spectrum value at the last “extracted” mode. Changing this value to SPECTRUM instructs CAESAR II to use the last spectrum value as the ZPA for the missing mass computations.
Bend Axial Shape
For bends 45 degrees or smaller, a major contributor to deformation can be the axial displacement of the short-arched pipe. With the axial shape function disabled this displacement mode is ignored and the bend will be stiffer.
Rod Tolerance (degrees)
The angular plus-or-minus permitted convergence error. Unless the change from iteration “n” to iteration “n+1” is less this value, the rod will NOT be converged. The default of CAESAR II is 1.0 degree. For systems subject to large horizontal displacements, values of 5.0 degrees for convergence tolerances have been used successfully.
Rod Increment (degrees)
The maximum amount of angular change that any one support can experience between iterations. For difficult-to-converge problems, values of 0.1 have proven effective here. When small values are used, however, the user should be prepared for a large number of iterations. The total number of iterations can be estimated from:
Est. No. Iterations = 1.5(x)/(r)/(Rod Increment) Where:
x - maximum horizontal displacement at any one rod. r - rod length at that support
Alpha Tolerance
The breakpoint at which CAESAR II decides that the entry in the Temp fields on the input spreadsheet is a thermal expansion coefficient or a temperature. The default is 0.05. This means that any entry in the Temp fields whose absolute magnitude is less than 0.05 is taken to be a thermal expansion coefficient in terms of inches per inch (dimensionless). Use of this field provides some interesting modeling tools. If an Alpha Tolerance of 1.1 is set, then an entry in the Temp 2 field of -1 causes the element defined by this expansion coefficient to shrink to zero length. This alternate method of specifying cold spring is quite useful in jobs having hanger design with cold spring (see chapter 6 (see "Technical Discussions" on page 1) for more details regarding Cold Spring).
Ambient Temperature
If 0.0 is entered here, the default ambient temperature for all elements in the system is (degrees ^07) . If this does not accurately represent the installed, or zero expansion strain state, then enter a different value in this field.
Friction Stiffness
Friction restraint stiffness. The default is 1E6 lb/in. This value is used when a friction restraint is "non-sliding." In the "non-sliding" state, stiffnesses are inserted in the two directions perpendicular to the restraint’s line of action and opposing any sliding motion. This is the first parameter that should be adjusted to help a slowly converging problem where friction is suspected. Lower stiffness values permit more "non-sliding" movement, but given the indeterminate nature of the friction problem in general, this error is not considered crucial.
Friction Normal Force Variation
This tolerance, default of 0.15, or 15 percent, is the amount of variation in the normal force that is permitted before an adjustment will be made in the sliding friction force. This value normally should not be adjusted.
Friction Angle Variation
Friction sliding angle variation. The default is 15 degrees. This parameter had more significance in versions prior to 2.1. This parameter is currently only used in the first iteration when a restraint goes from the non-sliding to sliding state. All subsequent iterations compensate for the angle variation automatically.
Friction Slide Multiplier
This is an internal friction sliding force multiplier and should never be adjusted by the user unless so directed by a member of the COADE/CAESAR II support staff.
Coefficient of Friction (Mu)
The value specified here is applied by default as the coefficient of friction to all translational restraints. Specifying a value of zero, the default, means that no friction is applied.
WRC-107 Version
This directive sets the Version of the WRC-107 bulletin used in the computations. Valid options are: August 1965
March 1979
March 1979 with the 1B1-1 and 2B-1 off axis curves (default)
WRC-107 Interpolation Method
The curves in WRC Bulletin 107 cover essentially all applications of nozzles in vessels or piping; however, should any of the interpolation parameters i.e., U, Beta, etc. fall outside the limits of the available curves then some extension of the WRC method must be used.
The default is to use the last value in the particular WRC table. Alternatively, the user may control this extensions methodology interactively. This causes the program to prompt the user for curve values when necessary.
Incore Numerical Check
Enables the in-core solution module to test the stability of the solution for the current model and loadings. This option, if enabled, adds the solution of an extra load case to the job stream.
Decomposition Singularity Tolerance
The default value is 1.0 e+10. CAESAR II checks the ratio of off-diagonal coefficients to the on-diagonal coefficient in the row. If this ratio is greater than the decomposition singularity tolerance, then a numerical error may occur. This problem does not have to be associated with a system singularity. This condition can exist when very small, and/or long pipes are connected to very short, and/or large pipes. The out-of-core solution will, however, stop with a singularity message. This solution abort will prevent any possibility of an errant solution. These solutions have several general characteristics:
When machine precision errors of this type occur they are very local in nature, affecting only a single element or very small part of the model, and are readily noticeable upon inspection.
The 1E10 limit can be increased to 1E11 or 1E12 and still provide a reasonable check on solution accuracy. Any solution computed after this limit has been increased should always be checked closely for “reasonableness.” At 1E11 or 1E12 the number of significant figures in the local solution has been reduced to two or three.
The 1E10 limit can be increased to 1E20 or 1E30 to get the job to run, but the user should remember that the possibility for a locally errant solution exists when stiffness ratios are allowed to get this high. Solutions should be carefully checked.
Minimum Wall Mill Tolerance (%)
Use this directive is to specify the default percentage of wall thickness allowed for mill and other mechanical tolerances.
Note: For most piping codes, this value is only used during the "minimum wall thickness" computation. Mill tolerance is usually not considered in the flexibility analysis.
By default this value is 12.5, corresponding to a 12.5% tolerance. To eliminate mill tolerance consideration, set this directive to 0.0.
Bourdon Pressure
Select the BOURDON PRESSURE EFFECT from the drop list. The BOURDON EFFECT causes straight pipe to elongate, and bends to "OPEN UP" translationally along a line connecting the curvature end points. If the BOURDON EFFECT is not activated there will be no global displacements due to pressure.
BOURDON PRESSURE OPTION #1 (TRANSLATION ONLY) includes only translational effects.
BOURDON PRESSURE OPTION #2 (TRANSLATION & ROTATION) includes translational and rotational effects on bends. OPTION #2 may apply for bends that are formed or rolled from straight pipe, where the bend cross section will be slightly oval due to the bending process.
Note: OPTION #1 is the same as OPTION #2 for straight pipe. For elbows, OPTION #1 should apply for forged and welded fittings where the bend cross section can be considered essentially circular.
Note: The BOURDON EFFECT (translation only) is always considered when FRP pipe is used, regardless of the actual setting of the BOURDON FLAG.
Ignore Spring Hanger Stiffness
Enabling this option causes CAESAR II to ignore the stiffness of spring hangers in the analysis. This option is consistent with hand computation methods of spring hanger design, which ignored the effects of the springs.
Important: COADE recommends that this value never be changed.
Include Spring Stiffness in Hanger OPE Travel Cases
Enabling this option defaults CAESAR II to place the designed spring stiffness into the Hanger Operating Travel Case and iterate until the system balances. This iteration scheme therefore considers the effect of the spring hanger stiffness on the thermal growth of the system (vertical travel of the spring). If this option is used, it is very important that the hanger load in the cold case (in the physical system) be adjusted to match the reported hanger Cold Load.
Hanger Default Restraint Stiffness
Where hangers are adjacent to other supports or are themselves very close (for example where there are two hangers on either side of a trunnion support), the CAESAR II hanger design algorithm may generate poorly distributed hot hanger loads in the vicinity of the close hangers. Using a more flexible support for computing the hanger restrained weight loads often allows the design algorithm to more effectively distribute the system’s weight. A typical entry is 50,000; the default value is (1.0E12 lb/in).
Default Translational Restraint Stiffness
This directive defines the value used for non-specified translational restraint stiffnesses. By default this value is assumed to be (1.0E12 lb./in).
Default Rotational Restraint Stiffness
This directive defines the value used for non-specified rotational restraint stiffnesses. By default this value is assumed to be (1.0E12 in-lb/deg).
SIFs and Stresses
SIFs and Stresses Configuration Settings
Default Code
The piping code the user designs to most often should go here. This code will be used as the default if no code is specified in the problem input. The default piping code is B31.3, the chemical plant and petroleum refinery code. Valid entries are B31.1, B31.3, B31.4, B31.4 Chapter IX, B31.5, B31.8, B31.8 Chapter VIII, B31.11, ASME-NC(Class 2), ASME-ND(Class 3), NAVY505, Z662, BS806, SWEDISH1, SWEDISH2, B31.1-1967, STOOMWEZEN, RCCM-C, RCCM-D, CODETI, Norwegian, FDBR, BS-7159, UKOOA, IGE/TD/12, and DNV.
Occasional Load Factor
The default value of 0.0 tells CAESAR II to use the value that the active piping code recommends. B31.1 states that the calculated stress may exceed the maximum allowable stress from Appendix A, (Sh), by 15% if the event duration occurs less than 10% of any 24 hour operating period, and by 20% if the event duration occurs less than 1% of any 24 hour operating period. The default for B31.1 applications is 15%. If 20% is more suitable for the system being analyzed then this directive can be used to enter the 20%. B31.3 states, “The sum of the longitudinal stresses due to pressure, weight, and other sustained loadings
(S1) and of the stresses produced by occasional loads such as wind or earthquake may be as much as 1.33 times the allowable stress given in Appendix A. Where the allowable stress value exceeds 2/3 of yield strength at temperature, the allowable stress value must be reduced as specified in Note 3 in 302.3.2.” The default for B31.3 applications is 33%. If this is too high for the material and temperature specified then a smaller occasional load factor can be input.
Yield Stress Criterion
The 132 column stress report produced by CAESAR II contains a value representative of the maximum stress state through the cross section, computed per the indicated yield criteria theory.
CAESAR II can compute this maximum stress (note, this is not a Code stress) according to either Von Mises Theory or the Maximum Shear Theory. The selected stress is computed at four points along the axis normal to the plane of bending (outside top, inside top, inside bottom, outside bottom), and the maximum value is printed in the stress report. The equations used for each of these yield criteria are listed below. If the Von Mises Theory is used, CAESAR II computes the octahedral shear stress, which differs from the Von Mises stress by a constant factor.
(For B31.4 Chapter IX, B31.8 Chapter VIII, and DnV this setting controls which equation is used to compute the "equivalent stress". For these three codes, the equations shown in the code are used to determine the yield criterion, not the standard mechanical stress equations shown below. These standard mechanical stress equations are used for the other codes addressed by CAESAR II. )
3D Maximum Shear Stress Intensity (Default) SI = Maximum of:
S1OT - S3OT S1OB - S3OB
Max(S1IT,RPS) - Min(S3IT,RPS) Max(S1IB,RPS) - Min(S3IB,RPS) Von Mises Stress (Octahedral)
OCT = Maximum of:
(S3OB2+S1OB2+(S3OB-S1OB)2)1/2 / 3.0
((S3IB-RPS)2+(S3IB-S1IB)2+(RPS-S1IB)2)1/2 / 3.0 (S3OT2+S1OT2+(S1OT-S3OT)2)1/2 / 3.0
((S3IT-RPS)2+(S3IT-S1IT)2+(RPS-S1IT)2)1/2 / 3.0 Where:
S1OT=Maximum Principal Stress, Outside Top = (SLOT+HPSO)/2.0+(((SLOT-HPSO)/2.0)2+TSO2)1/2 S3OT=Minimum Principal Stress, Outside Top =(SLOT+HPSO)/2.0- (((SLOT-HPSO)/2.0)2+TSO2)
S1IT=Maximum Principal Stress, Inside Top =(SLIT+HPSI)/2.0+(((SLIT-HPSI)/2.0)2+TSI2) 1/2 S3IT=Minimum Principal Stress, Inside Top =(SLIT+HPSI)/2.0- (((SLIT-HPSI)/2.0)2+TSI2) 1/2 S1OB=Maximum Principal Stress, Outside Top =(SLOB+HPSO)/2.0+ (((SLOB-HPSO)/2.0)2+TSO2) 1/2 S3OB=Minimum Principal Stress, Outside Bottom =(SLOB+HPSO)/2.0- (((SLOB-HPSO)/2.0)2+TSO2) 1/2 S1IB=Maximum Principal Stress, Inside Bottom =(SLIB+HPSI)/2.0+ (((SLIB-HPSI)/2.0)2+TSI2) 1/2 S3IB=Minimum Principal Stress, Inside Bottom =(SLIB+HPSI)/2.0- (((SLIB-HPSI)/2.0)2+TSI2) 1/2 RPS=Radial Pressure Stress, Inside
HPSI=Hoop Pressure Stress (Inside, from Lame’s Equation) HPSO=Hoop Pressure Stress (Outside, from Lame’s Equation) SLOT=Longitudinal Stress, Outside Top
SLIT=Longitudinal Stress, Inside Top SLOB=Longitudinal Stress, Outside Bottom SLIB=Longitudinal Stress, Inside Bottom TSI=Torsional Stress, Inside
TSO=Torsional Stress, Outside
B31.3 Sustained Case SIF Factor
B31.3 Code Interpretation 1-34 dated February 23, 1981 File: 1470-1 states that for sustained and occasional loads an SIF of 0.75i, but not less than 1.0 may be used. This setup directive allows the user to enter his/her own coefficient. The default is 1.0. To comply with this interpretation the user would enter 0.75. B31.3 Code Interpretation 6-03 dated December 14, 1987 permitted users to ignore the stress intensification for sustained and occasional loads.To comply with this interpretation, the user would enter 0.0.
B31.3 Welding and Contour Insert Tees Meet B16.9
This flag controls the "assumption" that the geometry of B31.3 welding and contour insert tees (sweepolets) meet the dimensional requirements of the code, and can be classified as B16.9 tees. The default setting for this directive is "NO", which causes the program to use a flexibility characteristic of 3.1*T/r, as per the A01 addendum.
Selecting this checkbox, allows the program to assume that the fitting geometry meets the requirements of Note 11, introduced in the A01 addendum, and a flexibility characteristic of 4.4*T/r will be used.
Note: In order to match runs made with CAESAR II prior to Version 4.40, this checkbox must be selected. Prior to Version 4.40, CAESAR II always used a flexibility characteristic of 4.4*T/r.
Allow User's SIF at Bend
This feature was added for those users that wished to change the stress intensification factor for bends. Previously this was not permitted, and the code defined SIF was always used. If the user enables this directive, he may override the code’s calculated SIF for bends. The user entered SIF acts over the entire bend curvature and must be specified at the “TO” end of the bend element. The default is off.
Use WRC329
This directive activates the WRC329 guidelines for all intersections, (not just for reduced intersections). The recommendations made by Rodabaugh in section 5.0 of WRC329 will be followed exactly in making the stress calculations for intersections. Every attempt has been made to improve the stress calculations for all codes, not just the four discussed in Rodabaugh’s paper. Users not employing either B31.1, B31.3 or the ASME NC or ND codes, and who wish to use WRC329 are encouraged to contact COADE for additional information. Throughout this document WRC330 and WRC329 are used synonymously (330 was the draft version of 329). When finally published, the official WRC designation was 329.
Use Schneider
This directive activates the Schneider reduced intersection assumptions. It was because of observations by Schneider that much of the work on WRC 329 was started. Schneider pointed out that the code SIFs could be in error when the d/D ratio at the intersection was less than 1.0 and greater than 0.5. In this d/D range the SIFs could be in error by a factor as high as 2.0. Using the Schneider option in CAESAR II results in a multiplication of the out of plane branch stress intensification by a number between 1 and 2 when the d/D ratio for the intersection is between 0.5 and 1.0. For B31.1 and other codes that do not differentiate between in and out-of-plane SIFs the multiplication will be used for the single stress intensification given.
All Cases Corroded
A recent version of the B31.3 piping code mentioned reducing the section modulus for sustained or occasional stress calculations by the reduction in wall thickness due to corrosion. Several users have interpreted this to mean that the reduced section modulus should be used for all stress calculations, including expansion. This directive allows those users to apply this conservative interpretation of the code. Enabling All Cases Corroded causes CAESAR II to use the corroded section modulus for the calculation of all stress types. This method is recommended as conservative, and probably more realistic as corrosion can significantly affect fatigue life, i.e., expansion. Disabling this directive causes CAESAR II to strictly follow the piping code recommendations, i.e. depending on the active piping code, some load cases will consider corrosion and some will not.
Liberal Expansion Stress Allowable
Activate this check box in order to cause CAESAR II to default new jobs to use the “Liberal Expansion Stress Allowable” – to add the difference between the hot allowable stress and the sustained stress to the allowable expansion stress range (if permitted by the particular code in use).
Deactivating this option causes new jobs to default to not using this allowable.
WRC 329
Allows the user to use the recommendations of WRC 329 for reduced intersections. A reduced intersection is any intersection where the d/D ratio is less than 0.975. The WRC 329 recommendations result in more conservative stress calculations in some instances and less conservative stress calculations in others. In all cases the WRC 329 values should be more accurate, and more truly in-line with the respective codes intent.
Base Hoop Stress On ( ID/OD/Mean/Lamés )
This directive is used to indicate how the value of hoop stress should be calculated. The default is to use the ID of the pipe. Most piping codes consider the effects of pressure in the longitudinal component of the CODE stress. Usually, the value of the hoop stress has no bearing on the CODE stress, so changing this directive does not affect the acceptability of the piping system.
If desired, the user may change the way CAESAR II computes the hoop stress value. This directive has the following options:
ID—Hoop stress is computed according to Pd/2t where “d” is the internal diameter of the pipe. OD—Hoop stress is computed according to Pd/2t where “d” is the outer diameter of the pipe. Mean—Hoop stress is computed according to Pd/2t where “d” is the average or mean diameter of the pipe.
Lamés—Hoop stress is computed according to Lamés equation, = P ( Ri2+ Ri2* Ro2/ R2) / ( Ro2 -Ri2) and varies through the wall as a function of R.
Use PD/4t
Enabling this directive causes CAESAR II to use the simplified form of the longitudinal stress term when computing sustained stresses. Some codes permit this simplified form when the pipe wall thickness is thin. This option is used most often when users are comparing CAESAR II results to those from an older pipe stress program. The more comprehensive calculation, i.e. the Default, is recommended.
Add F/A in Stresses
Determines whether or not the axial stress term is included in the code stress computation. Setting this directive to Default causes CAESAR II to use whatever the currently active piping code recommends. Only the B31.3-type piping codes (i.e. codes where the sustained stress equation is not explicitly given) have the F/A stresses included in the sustained and occasional stress equations. The B31.1-type codes do not include the F/A stresses because the equations given explicitly in the code do not include it. The F/A stresses discussed here are not due to longitudinal pressure. These are the F/A stresses due to structural loads in the piping system itself.
Add Torsion in SL Stress
Some piping codes include torsion in the sustained and occasional stresses by explicitly including it in the stress equation (i.e. B31.1), and some don’t include torsion in the sustained and occasional stresses by implicitly calling for “longitudinal stresses” only (i.e. B31.3). Setting the Add Torsion in SL Stress directive to Yes forces CAESAR II to include the torsion term in those codes that don’t include it already by default. Setting this directive to Default causes CAESAR II to use whatever the currently active piping code implies. In a sustained stress analysis of a very hot piping system subject to creep, it is recommended that the user include torsion in the sustained stress calculation via this parameter in the setup file.
Stress Stiffening Due to Pressure
This flag instructs the program to include pressure stiffening effects on straight pipes. The options for this flag are:
0 - no stiffening of straight pipes due to pressure 1 - elemental stiffening using Pressure #1 2 - elemental stiffening using Pressure #2
Reduced Intersection
Available options are B31.1(Pre 1980), B31.1(Post 1980), WRC329, ASME SEC III, and Schneider:
B31.1 (Pre 1980)
Allows the B31.1 code user to have the pre-1980 code rules used for reduced intersection. These rules did-not define a separate branch SIF for the reduced branch end. The branch stress intensification factor will be the same as the header stress intensification factor regardless of the branch-to-header diameter ratio.
B31.1 (Post 1980)
Allows the B31.1 code user to employ the post-1980 code rules for reduced intersections. The reduced intersection SIF equations in B31.1 from 1980 through 1989 generated unnecessarily high SIFs because of a mistake made in the implementation. (This is as per WRC329.) For this reason many users opted for the “Pre 1980” B31.1 SIF calculation discussed above. CAESAR II corrects this mistake by the automatic activation of the flag: B31.1 Reduced Z Fix = On. Users can vary the status of this flag in the CAESAR II setup file to generate any interpretation of B31.1 desired. The default for a new job is for B31.1(Post 1980) and for the B31.1 Reduced Z Fix = On.
The No RFT/WLT in Reduced Fitting SIFs flag also affects the SIF calculations at reduced intersections and is also available in this release.
WRC 329
Allows the user to use the recommendations of WRC329 for reduced intersections. A reduced intersection is any intersection where the d/D ratio is less than 0.975. The WRC329 recommendations result in more conservative stress calculations in some instances and less conservative stress calculations in others. In all cases the WRC329 values should be more accurate, and more truly in-line with the respective codes intent.
ASME Sect. III
Allows the user to use the 1985 ASME Section III NC and ND rules for reduced intersections.
Schneider
Activates the Schneider reduced intersection stress intensification factor multiplication. Has the same effect as the Use Schneider option.
Class 1 Branch Flexibility
Activates the Class 1 flexibility calculations. The appearance of this parameter in the setup file will completely change the modeling of intersections in the analysis. For intersections not satisfying the reduced branch rules that d/D 0.5 and that D/T 100, the branch will start at the surface of the header pipe. A perfectly rigid junction between the centerline of the header and surface will be formed automatically by CAESAR II using the element offset calculations. SIFs act at the surface point for the branch. When the reduced branch rules are satisfied, the local flexibility of the header is also inserted at this surface point. Intersections not satisfying the reduced intersection rules will be “stiffer” and carry more load, while intersections satisfying the reduced intersection rules will be more flexible and will carry less load. All changes to the model are completely transparent to the user. In systems where the
intersection flexibility is a major component of the overall system stiffness, the user is urged to run the analysis both with and without the Class 1 Branch Flexibility active to determine the effect this modeling on the analysis. For more technical discussion, refer to Class 1 Branch Flexibilities (on page 14).
B31.1 Reduced Z Fix
This directive is used in conjunction with B31.1, and makes the correction to the reduced branch stress calculation that existed in the 1980 through 1989 versions of B31.1. This error was corrected in the 1989 version of B31.1, and the B31.1 Reduced Z Fix is on by default in CAESAR II.
Schneider
Activates the Schneider reduced intersection stress intensification factor multiplication. Has the same effect as the Use Schneider option.
No RFT/WLT in Reduced Fitting SIFs
There has been considerable concern involving the SIFs for reduced fittings. Part of the discussion centers around just what should be considered a reduced fitting. The CAESAR II default is to assume that welding tees and reinforced fabricated tees are covered by the reduced fitting expressions, even though the reduced fitting expressions do not explicitly cover these intersection types. Users wishing to leave welding tees and reinforced tees out of this definition should enable this directive.
Apply B31.8 Note 2
The B31.8 piping code defines both "in-plane" and "out -of -plane" SIF values. The notes to Appendix E, B31.8 states that a more conservative approach can be taken, by using the "out-of-plane" SIF value for the "in-plane" value (Note 2). This directive controls whether or not this more conservative approach is used.
Prior to Version 4.30, CAESAR II always applied Note 2, the more conservative approach, and there was no way to alter this behavior.
The user can control (through the use of this directive) whether or not Note 2 is implemented. The default behavior is to use the two different SIF values and not employ Note 2.
Pressure Variation in Expansion Cases
This directive controls whether or not any pressure variation (between the referenced load cases) will appear in the resulting expansion load case.
Geometry Directives
Geometry Directives Configuration Settings
Connect Geometry Through Cnodes
Restraints, flexible nozzles, and spring hangers may be defined with connecting nodes. By default CAESAR II ignores the position of the restraint node and the connecting node. They may be at the same point or they may be hundreds of feet apart. This directive allows the user to insist that each restraint, nozzle, or hanger exists at the same point in space as its connecting node. In many cases, enabling this option will cause “plotwise” disconnected parts of the system to be reconnected and to appear “as -expected” in both input and output plots.
Auto Node Number Increment
This directive sets the value for the Automatic Node Numbering routine. Any non-zero, positive value in this data cell is used to automatically assume the “TO NODE” value on the piping input spreadsheets. The new (TO) node number is determined as:
“To Node” = “From Node” + Auto Node Number Increment. If this value is set to 0.0, automatic node numbering is disabled.
Z-Axis Vertical
By default CAESAR II assumes the Y axis is vertical with the X and Z axes in the horizontal plane. If desired, the Z axis can be made vertical by checking this box. In this case, the X and Y axes will be in the horizontal plane.
Minimum Allowed Bend Angle
Very small angles, short radius bends can cause numerical problems during solution. When the user has a reasonable radius and a small angle there are usually no problems. However, if the small angle bend is grossly small compared to the surrounding elements then the bend should probably not be used and a different modeling approach employed. Enabling this directive allows the user to reset the minimum angle CAESAR II will accept for a bend angle. The default is 5.0 degrees.
Maximum Allowed Bend Angle
Very large angles, short radius bends can cause numerical problems during solution. When the user has a reasonable radius and a large angle there are usually no problems. However, if the large angle bend plots compared reasonably well to the surrounding elements then the bend can probably be used without difficulty. Well-proportioned bends up to 135 degrees have been tested without a problem. Enabling this directive allows the user to reset the maximum angle CAESAR II will accept for a bend. The default is 95 degrees.
Bend Length Attachment Percent
Whenever the element leaving the tangent intersection of a bend is within (n)% of the bend radius on either side of the weldline, CAESAR II inserts an element from the bend weldline to the “TO” node of the element leaving the bend. The inserted element has a length equal to exactly (n)% of the bend radius. The user may adjust this percentage to reduce the error due to the inserted element, however, the length tolerance for elements leaving the bend will also be reduced. To obtain more accurate results the user must include less “slop” in the system dimensions around bends. The default attachment is 1.0 percent.
Minimum Angle to Adjacent Bend
Nodes on a bend curvature that are too close together can cause numerical problems during solution. Where the radius of the bend is large, such as in a cross country pipeline, it is not uncommon to find nodes on a bend curvature closer than 5 degrees. In these situations the user may enable this directive to change the CAESAR II error checking tolerance for the “closeness” of points on the bend curvature. The default is 5.0 degrees.
Loop Closure Tolerance
The loop closure tolerance used by CAESAR II for error checking can be set interactively by the user for each job analyzed, or the user can enter the desired loop closure tolerance via this directive and override without distraction the program default value of 1.0 in. See the following section for a discussion of the CAESAR II units file.
Horizontal Thermal Bowing Tolerance
This directive enables the user to specify the maximum slope of a straight pipe element for which thermal
bowing effects will be considered. Thermal bowing is usually associated with fluid carrying horizontal
pipes in which the fluid does not fill the cross section. In these cases, there is a temperature differential across the cross section. This directive allows the user to define the interpretation of “horizontal.” By default, the program uses a value of 0.0001 as the horizontal threshold value. If a pipe element’s pitch is less than this tolerance, the element is considered to be horizontal, and thermal bowing loads can be applied to it. An element’s pitch is computed from:
Plot Colors
Plot Colors Configuration Settings
OPENGL Switch
By default the 3D Hoops graphics engine uses the OPENGL drivers. On some machines with older graphics cards, or older graphics drivers, OPENGL does not perform well. Unchecking this checkbox instructs the CAESAR II graphics engine to use the alternate Microsoft drivers, instead of the OPENGL drivers.
Pipes
Enter the color for the center-line and volume plots of pipe elements. Excludes valves, other rigids and expansion joints.
Nodes
Enter the color for the node numbers.
Rigids/Bends
Hangers/Nozzles
Enter the color for the hanger and nozzle symbols that are displayed on the input plot.
Structure
Enter the color that the structural elements should be plotted in. The color selected should contrast with the color entered for the Pipes.
Background
Enter the color for the plot background. The user should be careful setting this parameter because all other colors need to coordinate with the background color selected.
Axes
Enter the color of the plot axes that appear in the bottom left corner of the screen.
Labels
Enter the color for the geometry labels exclusive of the node numbers. Examples are, Diameter, Thickness, Length, Plot Labeling.
Highlights
Enter the color for the input level plot highlight. The color selected should contrast with the color entered for the Pipes.
Displaced Shape
Enter the color for the displaced shape overlay. The color selected should contrast with the color entered for the Pipes.
Stress Level 1
Enter the stress value that defines the lower limit cutoff.
Stress Level 2
Enter the stress value that defines the second lowest stress color-plot limit.
Stress Level 3
Enter the stress value that defines the third lowest stress color-plot limit.
Stress Level 4
Enter the stress value that defines the fourth lowest stress color-plot limit.
Stress Level 5
Stress < Level 1
Enter the color for that portion of the pipe that has a stress lower than Stress Level 1.
Stress > Level 1
Enter the color for that portion of the pipe that has a stress greater than Stress Level 1 and less than Stress Level 2.
Stress > Level 2
Enter the color for that portion of the pipe that has a stress greater than Stress Level 2 and less than Stress Level 3.
Stress > Level 3
Enter the color for that portion of the pipe that has a stress greater than Stress Level 3 and less than Stress Level 4.
Stress > Level 4
Enter the color for that portion of the pipe that has a stress greater that Stress Level 4 and less than Stress Level 5.
Stress > Level 5
Enter the color for the portion of the pipe element that has a stress greater than Stress Level 5. The color of an element from one end to the other varies as the stress varies.
FRP Pipe Properties
FRP Properties Configuration Settings
Use FRP SIF
By default, when FRP pipe is selected (Material #20), CAESAR II sets the fitting SIF to 2.3. Some users have requested that the standard “code” SIF be used, others have requested the ability to specify this value manually.
By disabling this directive, the standard “code” SIF equations will be applied to all FRP fittings. This also allows manual specification of these values by the user.
If the BS 7159 or UKOOA Codes are in effect, code SIFs will always be used, regardless of the setting of this directive.
Use FRP Flexibilities
By default, when FRP pipe is selected (Material #20), CAESAR II sets the fitting flexibility factor to 1.0. Some users have requested that the standard “code” flexibility factor be used.
By disabling this directive, the standard “code” flexibility factor equations will be applied to all FRP fittings.
If the BS 7159 or UKOOA Codes are in effect, code flexibility factors will always be used, regardless of the setting of this directive.
FRP Property Data File
Standard FRP material properties may be read in from files. The user may select the available files. Once selected, the program will give the user the option of reading in from that file.
Users may create FRP material files as text files with the .frp extension; these files should be stored in the CAESAR\SYSTEM sub-directory. The format of the files must adhere to the following format:
Sample FRP Data File
Note: The data lines must follow exactly the order shown above. The four data lines defining the UKOOA envelope are intended for future use and may be omitted.
BS 7159 Pressure Stiffening
The BS 7159 code explicitly requires that the effect of pressure stiffening on the bend SIFs be calculated using the Design Strain (this is based upon the assumption that the FRP piping is fully pressurized to its design limit). This is CAESAR II’s default method.
When the piping is pressurized to a value much lower than its design pressure, it may be more accurate to calculate pressure stiffening based on the Actual Pressure stress, rather than its design strain. Note that this alternative method is a deviation from the explicit instructions of the BS 7159 code.
FRP Laminate Type
The default Laminate Type (as defined in the BS 7159 code) of the fiberglass reinforced plastic pipe used should be entered. Valid laminatetypes are
Chopped strand mat (CSM) and woven roving (WR) construction with internal and external surface
tissue reinforced layer.
Chopped strand mat (CSM) and multi-filament roving construction with internal and external surface tissue reinforced layer.
All chopped strand mat (CSM) construction with internal and external surface tissue reinforced layer. This entry is used in order to calculate the flexibility and stress intensity factors of bends; therefore this default entry may be overridden using the Type field on the bend auxiliary spreadsheets.
Exclude f2 from UKOOA Bending Stress
Some sources, such as Shell's DEP 31.40.10.19-Gen. (December 1998) and ISO/DIS 14692 suggest that, when using the UKOOA code, the axial bending stress should not be multiplied by the Part Factor f2 (the System Factor of Safety) prior to combination with the longitudinal pressure stress. Users wishing to modify the UKOOA requirements in this way should enable this check box. Users wishing to use UKOOA exactly as written should disable this check box.
FRP Pipe Density
Weight of the pipe material on a per unit volume basis. This field is used to set the default weight density of FRP materials in the piping input module.
FRP Alpha (e-06)
In this field, the thermal expansion coefficient for the fiberglass reinforced plastic pipe used (multiplied by 1,000,000) should be entered. For example, if the value is: 8.5E-6 in/in/deg, then the user would enter 8.5 in this field. The exponent (E-6) is implied.
If a single expansion coefficient is too limiting for the user’s application, the actual thermal expansion may always be calculated at temperature in inches per inch (or mm per mm) and entered directly into the Temperature field on the Pipe spreadsheet.
FRP Modulus of Elasticity
Axial elastic modulus of Fiberglass Reinforced Plastic pipe. This is the default value used to set the data in the input processor. The user may override this value in the input when necessary.
Ratio Shear Mod:Emod
In this field, the ratio of the shear modulus to the modulus of elasticity (in the axial direction) of the fiberglass reinforced plastic pipe used should be entered. For example, if the material modulus of elasticity (axial) is 3.2E6 psi, and the shear modulus is 8.0E5 psi, the ratio of these two, 0.25, should be entered here.
Axial Strain:Hoop Stress (Ea/Eh*Vh/a)
The product of the ratio of the axial to the hoop elastic modulus and Poisson's ratio which relates the strain in the axial direction to a stress in the hoop direction.
Ea - Elastic modulus in the axial direction. Eh - Elastic modulus in the hoop direction.
Database Definitions
Database Definitions Configuration Settings
Structural Database
This directive specifies which database file is to be used to acquire the structural steel shape labels and cross section properties from. The structural databases provided include AISC 1977, AISC 1989, German 1991, South African 1991, Korean 1990, Australian 1990, and United Kingdom.
Piping Size Specification (ANSI/JIS/DIN/BS)
By default, CAESAR II uses the ANSI pipe size and schedule tables in the input processor. Users may optionally select the standard tables of another piping specification using this directive. The available tables are
American National Standard (ANSI) Japanese Industrial Standard (JIS) German Standard (DIN)
Valves and Flanges
This directive enables the user to specify which Valve/Flange database should be referenced by CAESAR II during subsequent input sessions. The databases provided include the following: a generic database, the Crane database, a database (generic) without attached flanges, and the CADWorx/Pipe database.
Expansion Joints
This directive enables the user to specify which Expansion Joint database should be referenced by CAESAR II during subsequent input sessions. The databases provided include Pathway, Senior Flexonics, IWK, and Piping Technology.
Units File Name
This directive allows the user to scroll through the available units files and select one to activate. Since the CAESAR.CFG file is written to the local data directory, different data directories can be configured to reference different units files.
Units files are searched for first in the local data directory, and then in the “active SYSTEM” directory. The active units file is used for new job creation and all output generation.
Load Case Template
This directive allows the user to scroll through the available load case templates and select the one to be active. Since the CAESAR.CFG file is written to the local data directory, different data directories can be configured to reference different template files.
Template files are searched for first in the local data directory, and then in the "active SYSTEM" directory. The active template file is used to "recommend" load cases.
System Directory Name
This directive enables a user to select which “SYSTEM” directory is used by CAESAR II. All of the various system directories contain formatting files, units files, text files, and other “user configurable” data files. Some of these formatting files are language specific or Code specific. Therefore, users may want to switch between system directories depending on the current job. The directive allows the user to scroll through the available system directories and select one to be ACTIVE. Since the CAESAR.CFG file is written to the local data directory, different data directories can be configured to reference different system directories.
All system directory names must be of the form: SYSTEM.??? where the .??? is a three character suffix identifying the directory. Users can create system directories as needed, following this required naming convention. The CAESAR II distribution diskettes contain language files for English, French, German, and Spanish. These formatting files can be installed in separate system directories, with an appropriate suffix, to allow switching between languages.
Note that there must be a primary system directory, named system, for the program to place accounting, version, and diagnostic files that it creates during execution. The secondary system directories are only referenced for llanguage and formatting files.
Default Spring Hanger Table
This directive is used to set the value of the default spring hanger table, referenced during the spring hanger design stage of the solution. CAESAR II includes tables from more than 20 different vendors.
Enable Data Export to ODBC-Compliant Databases
Append Reruns to Existing Data
The default of NO (unchecked) causes a rerun to overwrite data from previous runs in the ODBC database. Turning this directive on (checked) causes a rerun to add new data to the database, thus storing multiple runs of the same job in the database.
ODBC Compliant Database Name
This field contains the name of the ODBC project database. All jobs run in this data directory will write their output to the database specified here.