193520810 Caesar Book Material

Name ID No Date Course

Kagira

Kagira Drawing Solution No: 21.A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044- 2454 2454 Cell: 9500 100 966/ 9940 582 820 www.kagira.com

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected], www.kagira.com

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Volume-I Pipeline and Piping component compliance 1. About Caesar......Page 1 2. Basic operation.....Page 2 3. Purpose of stress analysing...Page 2 4. Menu Commands.....Page 5 a. Node no & names, Element length, b. Pipe dia and Schedule, Temp& pressure 5. Tool menu...................................................................................................................................Page 13 6. Bend..............................................................................................................................................Page 19 7. Reducer........................................................................................................................................Page 24 8. Tee .........................................................................................................................................Page 25 9. Rigid(Valve and Flange)......................................................................................................Page 28 10. Restraints...................................................................................................................................Page 29 11. Hanger.........................................................................................................................................Page 36 12. Support Thick Calculation..................................................................................................Page 42 13. Nozzle..........................................................................................................................................Page 43 14. Displacement............................................................................................................................Page 53 15. Force and Movement............................................................................................................Page 54 16. Wind and Wave.......................................................................................................................Page 55 17. Stress Category.......................................................................................................................Page 58 18. Load combination..................................................................................................................Page 62 19. Allowable Stress.....................................................................................................................Page 63 20. Boiler Tube Calculation.......................................................................................................Page 74 21. Expansion Loop......................................................................................................................Page 76 22. Report Generation.................................................................................................................Page 79

CONTENT


Volume-II

Equipment and Component Compliance 1. Intersection Stress Intensification Factors Analysing.. Page 81 2. Bend Stress Intensification Factors Analysing.. Page 84 3. WRC 107 (Vessel Stresses) Analysing.... Page 86 4. WRC Bulletin 297 Analysing. Page 92 5. Flange Leakage/Stress Calculations Analysing. Page 96 6. Remaining Strength of Corroded Pipelines, B31G Analysing Page 103 7. Expansion Joint Rating Analysing.. Page 107 8. NEMA SM23 (Steam Turbines) Analysing. Page 113 9. API 610 (Centrifugal Pumps) Analysing. Page 118 10. API 617 (Centrifugal Compressors) Analysing.. Page 122 11. API 661 (Air Cooled Heat Exchangers) Analysing Page 124 12. Heat Exchange.... Page 127 13. API 560 Page 129 14. ExercisePage 131

Hard Work Never Fails

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page1

Volume- I What is CAESAR? CAESAR (Computer Aided Engineering Stress Analysing Reporter) is a PC-based pipe stress analysis software program developed, marketed and sold by COADE Engineering Software. This software package is an engineering tool used in the mechanical design and analysis of piping systems. The CAESAR user creates a model of the piping system using simple beam elements and defines the loading conditions imposed on the system. With this input, CAESAR produces results in the form of displacements, loads, and stresses throughout the system. Additionally, CAESAR compares these results to limits specified by recognized codes and standards. The popularity of CAESAR is a reflection of COADEs expertise in programming and engineering, as well as COADEs dedication to service and quality. What are the Applications of CAESAR? CAESAR is most often used for the mechanical design of new piping systems. Hot piping systems present a unique problem to the mechanical engineerthese irregular structures experience great thermal strain that must be absorbed by the piping, supports, and attached equipment. These structures must be stiff enough to support their own weight and also flexible enough to accept thermal growth. These loads, displacements, and stresses can be estimated through analysis of the piping model in CAESAR. To aid in this design by analysis, CAESAR incorporates many of the limitations placed on these systems and their attached equipment. These limits are typically specified by engineering bodies (such as the ASME B31 committees, ASME Section VIII, and the Welding Research Council) or by manufacturers of piping-related equipment (API, NEMA, or EJMA). CAESAR is not limited to thermal analysis of piping systems. CAESAR also has the capability of modeling and analyzing the full range of static and dynamic loads, which may be imposed on the system. Therefore, CAESAR is not only a tool for new design but it is also valuable in troubleshooting or redesigning existing systems. Here, one can determine the cause of failure or evaluate the severity of unanticipated operating conditions such as fluid/piping interaction or mechanical vibration caused by rotating equipment.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page2 Basic Operation Once you have started the program and opened the file, you will choose the required operation. Piping Input Generation Once the desired job name has been specified, users can launch the interactive model builder by selecting the Input-Piping entry of the Main Menu. The input generation of the model consists of describing the piping elements, as well as any external influences (boundary conditions or loads) acting on those elements. Each pipe element is identified by two node numbers, and requires the specification of geometric, cross sectional, and material data. The preferred method of data entry is the piping spreadsheet. WHAT IS STRESS ANALYSIS? Piping Stress analysis is a term applied to calculations, which address the static and dynamic loading resulting from the effects of gravity, temperature changes, internal and external pressures, changes in fluid flow rate and seismic activity. Codes and standards establish the minimum requirements of stress analysis. PURPOSE OF PIPING STRESS ANALYSIS Safety of piping and piping components Safety of connected equipment and supporting structure Piping deflections are within the limits

Temperature Effects and Stress Due to Temperature Change As we know, for any material changes in temperature result in volume change. An increase or decrease in temperature results in the expansion or contraction of a structure. To better understand this phenomenon, consider a steel wire with a length,, fixed at one end and free on the other end, is subjected to a temperature rise of . The wire will elongate by , as shown below:

Change in the Wire Length Due to Increase in Temperature

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The increase in the length, , is related to the changes in temperature by the following equation: (1) In this equation, represents changes in temperature in degrees Fahrenheit (), l is the original length, and is the coefficient of thermal expansion (or thermal coefficient) with the units of depends on the material type. The following shows the values of for a few commonly used building materials: Material Aluminum 0.00128 Stainless Steel 0.00099 Copper 0.00093 Mild Steel 0.00065 Concrete 0.00055 Masonry 0.00035 Wood 0.00030 As can be seen from the above table, aluminum has larger value than steel. This means that, subjected to the same temperature variations, aluminum structures undergo larger changes in volume than similar steel structures. If the structure is prevented from movements (restrained) while subjected to a temperature change, stresses will develop. Consider the same piece of wire used before with both ends restrained undergoing a temperature rise of . Since both ends of the wire are prevented from movement, stresses develop in the wire, forcing it to buckle.

Buckling of Restrained Wire Due to Increase in Temperature

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page4 To find how much these stresses are and what parameters they depend on, we first consider the wire without one of the end supports subjected to a temperature increase of . The wire extends by , and the wires length becomes .

Change in the Wire Length Due to Increase in Temperature Now, we push the right end of the wire to go back to its original length. This is the force that would have developed in the wire if both ends were restrained when the temperature was raised.

Force in the Wire Due to Change in Temperature As we know, the stress, , in the wire due to the force, , is:

(2) where is the cross-sectional area of the wire. We also remember that the modulus of elasticity, , is defined as: (3) Where is the strain, defined as:

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(4) Substituting equation (4) into (3): (5) Substituting equation (1) into (5):

(6) or (7) The above equation shows the relationship between the changes in temperature and the stress developed in the restrained structure. For aluminum and steel spatial structures undergoing extremely large temperature variations this may become an important issue to consider. However, in most typical cases of spatial structures the temperature effect may be neglected since the developed stresses are negligible.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page6 Menu Commands The CAESAR II piping input processor provides many commands, which can be run From the menu, toolbars or accelerator keys. The menu options are: Node Number Each element is identified by its end node number. Since each input screen represents a piping element, the element end points - the From node and To node must be entered. These points are used as locations at which information may be entered or extracted. The From node and To node are both required data fields. CAESAR II can generate both values if the AUTO_NODE_INCREMENT directive is set to other than zero using the Tools-Configure/Setup option of the Main Menu. Node Names Activating this checkbox allows the user to enter text names for the From and/or To nodes (up to ten characters). These names display instead of the node numbers on the graphic plots and in the reports (note some of the names may be truncated when space is not available).

Note CAESAR II can generate both values if the AUTO NODE INCREMENT directive is set to other than zero using the Tools-Configure/Setup option of the Main Menu.

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Element Lengths Lengths of the elements are entered as delta dimensions according to the X, Y, and Z rectangular coordinate system established for the piping system (note that the Y-axis represents the vertical axis). The delta dimensions DX, DY, and DZ, are the measurements along the X, Y, and Z-axes between the From node and To node. In most cases only one of the three cells will be used as the piping usually runs along the global axes. Where the piping element is skewed two or three entries must be made. One or more entries must be made for all elements except zero length expansion joints. Note When using feet and inches for compound length and length units, valid entries in this (and most other length fields) include formats such as: 3-6, 3 ft. -6 in, and 3-6- 3/16.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page8 Pipe Section Properties The elements outside diameter, wall thickness, mill tolerance (plus mill tolerance is used for IGE/TD/12 piping code only), and seam weld (IGE/TD/12 piping code only); corrosion allowance, and insulation thickness are entered in this block. These data fields carry forward from one screen to the next during the input session and need only be entered for those elements at which a change occurs. Nominal pipe sizes and schedules may be specified; CAESAR II converts these values to actual outside diameter and wall thickness. Outside diameter and wall thickness are required data inputs. Pipe Section Data Diameter The Diameter field is used to specify the pipe diameter. Normally, the nominal diameter is entered, and CAESAR II converts it to the actual outer diameter necessary for the analysis. There are two ways to prevent this conversion: use a modified UNITS file with the Nominal Pipe Schedules turned off, or enter diameters whose values are off slightly from a nominal size (in English units the tolerance on diameter is 0.063 in.). Use to obtain additional information and the current units for this input field. Available nominal diameters are determined by the active pipe size specification, set via the configuration program. The following are the available nominal diameters. ANSI Nominal Pipe ODs, in inches (file ap.bin) 1 1 2 2 3 3 4 5 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 42 JIS Nominal Pipe ODs, in millimeters (file jp.bin) 15 20 25 32 40 50 65 80 90 100 125 150 200 250300 350 400 450 500 550 600 650 DIN Nominal Pipe ODs, in millimeters (file dp.bin) 15 20 25 32 40 50 65 80 100 125 150 200 250 300 350 400 500 600 700 800 900 1000 1200 1400 1600 1800 2000 2200

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Wt/Sch The Wall Thickness/Schedule field is used to specify the thickness of the pipe. Normal input consists of a schedule indicator (such as S, XS, or 40), which will be converted to the proper wall thickness by CAESAR II. If actual thickness is entered, CAESAR II will accept it as entered. Available schedule indicators are determined by the active piping specification, set via the configuration program. The available schedules are listed below. ANSI B36.10 Steel Nominal Wall Thickness Designation S - Standard XS - Extra Strong XXS - Double Extra Strong

ANSI B36.10 Steel Pipe Numbers 10 20 30 40 60 80 100 120 140 160 ANSI B36.19 Stainless Steel Schedules 5S 10S 40S 80S Corrosion Enter the corrosion allowance to be used order to calculate a reduced section modulus. A setup file directive is available to consider all stress cases as corroded. Insulation Thick Enter the thickness of the insulation to be applied to the piping. Insulation applied to the outside of the pipe will be included in the dead weight of the system, and in the projected pipe area used for wind load computations. If a negative value is entered for the insulation thickness, the program will model refractory lined pipe. The thickness will be assumed to be the thickness of the refractory, inside the pipe.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page10 Operating Conditions: Temperatures and Pressures Up to nine temperatures and ten pressures (one extra for the hydrostatic test pressure) can be specified for each piping element. (The button with the ellipses dots is used to activate a window showing extended operating conditions input). The temperatures are actual temperatures (not changes from ambient). CAESAR II uses these temperatures to obtain the thermal strain and allowable stresses for the element from the Material Database. As an alternative, the thermal strains may be specified directly (see the discussion of ALPHA TOLERANCE in the Technical Reference Manual). Thermal strains have absolute values on the order of 0.002, and are unit less. Pressures are entered as gauge values and may not be negative. Each temperature and each pressure entered creates a loading for use when building load cases. Both thermal and pressure data carries forward from one element to the next until changed. Entering a value in the Hydro Pressure field causes CAESAR II to build a Hydro case in the set of recommended load cases.

Note CAESAR II uses an ambient temperature of 70F, unless changed using the Special Execution Parameters Option. T1 Max temp, T2 Min temp, T3 Min summer temp,T4 Max winter temp T5 Max temp (flow induced) (optional), T6 Min temp (flow induced) (optional) P1 MIP, P2 MOP, P3 Compressor operation, P4 Demand pressure HP Hydrotest pressure

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Special Element Information Special components such as bends, rigid elements, expansion joints and tees require additional information, which can be defined by enabling the component and entering data in the auxiliary screen. If the element described by the spreadsheet ends in a bend, elbow or mitered joint, the Bend checkbox should be set by double-clicking. This entry opens up the auxiliary data field on the right hand side of the input screen to accept additional data regarding the bend. CAESAR II usually assigns three nodes to a bend (giving near, mid, and far node on the bend). Double-clicking the Rigid checkbox (indicating an element that is much stiffer than the connecting pipe such as a flange or valve) opens an auxiliary data field to collect the component weight. For rigid elements, CAESAR II follows these rules: When the rigid element weight is entered, i.e. not zero, CAESAR II computes any extra weight due to insulation and contained fluid, and adds it to the user-entered weight value. The weight of fluid added to a non-zero weight rigid element is equal to the same weight that would be computed for an equivalent straight pipe. The weight of insulation added is equal to the same weight that would be computed for an equivalent straight pipe times 1.75. If the weight of a rigid element is zero or blank, CAESAR II assumes the element is an artificial construction element rather than an actual piping element, so no insulation or fluid weight is computed for that element. The stiffness of the rigid element is relative to the diameter (and wall & thickness) entered. Make sure that the diameter entered on a rigid element spreadsheet is indicative of the rigid stiffness that should be generated. If an element is an expansion joint, double-clicking that checkbox brings up an auxiliary screen, which prompts for stiffness parameters and effective diameter. Expansion joints may be modeled as zero-length (with all stiffnesses acting at a single point) or as finite CAESAR II - User Guide Data Fields Piping Input 5-7 length (with the stiffnesses acting over a continuous element). In the former case, all stiffnesses must be entered, in the latter; either the lateral or angular stiffness must be omitted. Checking the SIF & Tees checkbox allows the user to specify any component having special stress intensification factors (SIF). CAESAR II automatically calculates these factors for each component.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page12 Note Bends, rigids, and expansion joints are mutually exclusive. Refer to the

valve/ flange and expansion joint database discussions later in this chapter for quick entry of rigid element and expansion joint data. Boundary Conditions The checkboxes in this block open the auxiliary data field to allow the input of items, which restrain (or impose movement on) the pipe restraints, hangers, flexible nozzles or displacements. Though not required, it is recommended that such information be supplied on the input screen which has that point as the From node or To node. (This will be of benefit if the data must be located for modification). The auxiliary data fields allow specification of up to 4 restraints (devices which in some way modify the free motion of the system), one hanger, one nozzle, or two sets of nodal displacements per element. If needed, additional items for any node can be input on other element screens. Loading Conditions The checkboxes in this block allow the user to define loadings acting on the pipe. These loads may be individual forces or moments acting at discrete points, distributed uniform loads (which may be specified on force per unit length, or gravitational body forces), or wind loadings (wind loadings are entered by specifying a wind shape factorthe loads themselves are specified when building the load cases. The uniform load and the wind shape factor check boxes will be unchecked on subsequent input screens. This does not mean that the loads were removed from these elements; instead, this implies that the loads do not change on subsequent screens.

Note Uniform loads may be specified in g-values by setting a parameter in the Special Execution Options.

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Piping Material CAESAR II requires the specification of the pipe materials elastic modulus, Poissons ratio, density, and (in most cases) expansion coefficient. The program provides a database containing the parameters for many common piping materials. This information is retrieved by picking a material from the drop list, by entering the material number, or by typing any the entire material name and then picking it from the match list. (The coefficient of expansion does not appear on the input screen, but it can be reviewed during error checking.) Note that materials 18 and 19 represent cold spring properties, cut short and cut long respectively; material 20 activates CAESAR IIs orthotropic model for use with materials such as fiberglass reinforced plastic pipe. Material 21 permits a totally user defined material. Using a material with a number greater than 100 permits the use of allowable stresses from the database. Material Elastic Properties This block is used to enter or override the elastic modulus and Poissons ratio of the material, if the value in the database is not correct. These values must be entered for Material type 21 (user specified).

Note Material properties in the database may be changed permanently using the CAESAR II Material Database

editor. Densities The densities of the piping material, insulation, and fluid contents are specified in this block. The piping material density is a required entry and is usually extracted from the Material Database. Fluid density can optionally be entered in terms of

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page14 specific gravity, if CAESAR II - User Guide Auxiliary Data Area Piping Input 5-9 convenient, by following the input immediately with the letters: SG, e.g. 0.85SG (there can be no spaces between the number and the SG).

Note If an insulation thickness is specified (in the pipe section properties block) but no insulation density is entered, CAESAR II defaults to the density of calcium silicate. Rockwool / Mineral wool Range

Rock Fibre is an Insulation material that is light in weight, made up of intermingled vitreous fibres composed of complex silicates. It is available in various forms like Loose Wool, Preformed Mattresses, Resin Bonded Slabs and Pipe Sections conforming to IS, ASTM, BS, JIS, DIN standards

MINROCK Lightly Resin Bonded Rock wool Mattresses of densities 85, 100, 120, 128 and 150 Kg/M3 and Thicknesses of 25mm, 40mm, 50mm, 65mm, 75mm, & 100mm are duly machine laid and machine stitched with one side/both sides wire netting conforming to IS: 8183/93 and are packed in Poly-Bonded HDPE Woven bags.

File Menu The File menu is used to perform actions associated with opening, closing and running the job file.

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File Menu for the Piping Input Screen

New Creates a new CAESAR II job. CAESAR II prompts for the name of the new model. Open Opens an existing CAESAR II job. CAESAR II prompts for the name Save Saves the current CAESAR II job under its current name. Save As Saves the current CAESAR II job under a new name. Save As Graphic Image

Saves the current CAESAR II job as an HTML page, .TIFF, .BMP, or .JPG file. Archive Allows the user to assign a password to prevent inadvertent alteration of the model or to enter the password to unlock the file. Start Run Sends the model through interactive error checking. This is the first step of analysis, followed by the building of the static load cases Batch Run Error checks the model in a non-interactive way and halts only for fatal errors; uses the existing or default static load cases, and performs the static analysis). The next step is the output processor. Print Allows the user to print out an input listing. CAESAR II prompts the user for the data items to include. Print Preview Provides print preview of input listing. Print Setup Sets up the printer for the input listing. Recent File List Open a file from the list of most recently used Jobs.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page16 Edit Menu The Edit menu provides commands for cutting and pasting, navigating through the spreadsheets, and performing a few small utilities. These commands are

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Continue Moves the spreadsheet to the next element in the model, adding a new element if there is no next element. Insert Inserts an element either before or after the current element Delete Deletes the current element. Find Allows the user to find an element containing one or more named nodes (if two nodes are entered, the element must contain both nodes). Enabling the Zoom To check box will display the element if found. Duplicate Copies the selected element either before or after the current element. Global Prompts the user to enter global (absolute) coordinates for the first node of any disconnected segments Close Loop Closes a loop by filling in the delta coordinates between two nodes on the spreadsheet. Increment Gives the user the opportunity to change the automatic node increment. Distance Calculates the distance between the origin and a node, or between two nodes. List Presents the input data in an alternative, list format that displays a drop down menu where users can select any list. This provides the benefit of showing all of the element data in a context setting. The list format also permits block operations such as Duplicate, Delete, Copy, Renumber on the element data. For more information on the list input format, see the Technical Reference Manual. Go to First Element, Previous Element, Skip to Next Element, Skip to Last Element

[Pg Dn], [Pg Up], Ctrl +[Home], Ctrl +[End]Allows users to move throughout the elements of a model. Note [Pg Dn] does not create a new element once the end of the model is reached. Edit Static Load Case

Opens the Static Load Case Editor window. This button is enabled when the job is error checked. Edit Dynamic Load Case

Opens the Dynamic Load Case Editor window. This button is enabled when the job is error checked. View Output Allows users to review the output report, provided the analysis was successfully completed Review Current Units

Located on the Edit Menu it allows users to review units used to create the report file. Changing units in the configuration file will not affect the input. To change Input units from the Main Menu use Tools-Convert Input to New Units. Undo/Redo Any modeling steps done in the CAESAR II input module may

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page18 be "undone", one at a time, using the Undo command, activated by clicking the Undo button on the toolbar, the Edit-Undo menu option, or the Ctrl-Z hot key. Likewise, any "undone" steps may be "redone" sequentially, using the Redo command, activated by the Redo button on the toolbar, the Edit-Redo menu option, or the Ctrl-Y hot key. An unlimited number of steps (limited only by amount of available memory) may be undone. Note that making any input change while in the middle of the "undo stack" of course resets the "redo" stack.

Model Menu The Model menu contains modeling aids, as well as means for entering associated, system wide information.

Break Allows the user to break the element into two unequal length elements or into many equal length elements. A single node may be placed as a break point anywhere along the element, or multiple nodes may be placed at equal intervals (the node step interval between the From and To nodes determines the number of nodes placed). Break Element Valve

Allows the user to model a valve or flange from one of the CAESAR II databases. Choosing a combination of Rigid Type, End Type, and Class constructs a rigid element with the length and weight extracted from the database. Expansion Joints Activates the Expansion Joint Modeler. The modeler automatically builds a complete assembly of the selected expansion joint style, using the bellows stiffnesses and rigid element weights extracted from one of the vendors expansion joint catalogs. Title Allows the user to enter a job title up to sixty lines long. By pressing T at any time during pipe spreadsheet input,

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the current job's title page will be displayed (also may access through the MODEL - TITLE menu item). This is up to 60 lines of text that is stored with the problem, and may be used for detailing run histories, discussing assumptions, etc. These lines may be printed with the output report through the input echo. Hanger Design Control Data

Prompts the user for system - wide hanger design criteria Environment Menu The Environment menu provides some miscellaneous items.

Environment Menu Review SIFs at Intersection Nodes Allows the user to run what if tests on the Stress Intensification Factors of intersections. Review SIFs at Bend Nodes Allows the user to run what if tests on the Stress Intensification Factors of selected bends. Special Execution Parameters Allows the user to set options affecting the analysis of the current job. Items covered include ambient temperature, pressure stiffening, displacements due to pressure (Bourdon effect), Z-axis orientation, etc.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page20 Piping Component

Bend Bend Definition Single and Double Flanged 180 Degree Return Fitting-To-Fitting 90 Degree Bends Mitered Bends Closely Spaced Mitered Bend Widely Spaced Mitered Bend Elbows - Different Wall Thickness Bend Flexibility Factor

Bend Definition Bends are defined by the element entering the bend and the element leaving the bend. The actual bend curvature is always physically at the TO end of the element entering the bend. The input for the element leaving the bend must follow the element entering the bend. The bend angle is defined by these two elements. Bend radius defaults to 1 1/2 times the pipe nominal diameter (long radius), but may be changed to any other value. Specifying a bend automatically generates two additional intermediate nodes, at the 0-degree location and at the bend midpoint (M). For stress and displacement output them TO node of the element entering the bend is located geometrically at the far-point on the bend. The far-point is at the weldline of the bend, and adjacent to the straight element leaving the bend. The 0-degree point on the bend is at the weldline of the bend, and adjacent to the straight element entering the bend.

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The FROM point on the element is located at the 0-degree point of the bend (and no 0-degree node point will be generated) if the total length of the element as specified in the DX, DY, and DZ fields is equal to: R tan ( / 2) Where is the bend angle, and R is the bend radius of curvature to the bend centerline. Nodes defined in the Angle and Node fields are placed at the given angle on the bend curvature. The angle starts with zero degrees at the near-point on the bend and goes to degrees at the far-point of the bend. Angles are always entered in degrees. Entering the letter M as the angle designates the bend midpoints. Nodes on the bend curvature cannot be placed closer together than specified by the Minimum Angle to Adjacent Bend parameter in the Configure-SetupGeometry section. This includes the spacing between the nodes on the bend curvature and the near and far-points of the bend. The minimum and maximum total bend angle is specified by the Minimum Bend Angle and maximum Bend Angle parameters in the Configure SetupGeometry section. Double-click the Bend checkbox. The Bends tab displays. This adds a long radius bend at the end of the element, and adds intermediate nodes 18 and 19 at the near weld and mid points of the bend respectively (node 20 physically represents the far weld point of the bend).

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page22 Single and Double Flanged Bends or Stiffened Bends Single and double flanged bend specifications only effect the stress intensification and flexibility of the bend. There is no automatic rigid element (or change in weight) generated for the end of the bend. Single and double-flanged bends are indicated by entering 1 or 2 (respectively) for the Type in the bend auxiliary input. Rigid elements defined before or after the bend will not alter the bend's stiffness or stress intensification factors. When specifying single flanged bends it does not matter which end of the bend the flange is on. If the user wishes to include the weight of the rigid flange(s) at the bend ends, then he/she should put rigid elements (whose total length is the length of a flange pair) at the bend ends where the flange pairs exist. As a guideline, British Standard 806 recommends stiffening the bends whenever a component that significantly stiffens the pipe cross section is found within two diameters of either bend end. The flanges in the figures below are modeled only to the extent that they affect the stiffness and the stress intensification for the bends.

Flanged Bends Singl Flange

Double Flange

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180 Degree Return Fitting-To-Fitting 90 Degree Bends Two 90-degree bends should be separated by twice the bend radius. The far-point of the first bend is the same as the near-point of the second (following) the bend. The user is recommended to put nodes at the midpoint of each bend comprising the 180 degree return. (See the example below.) 180 Degree Return Fitting (180 Degree bend)

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Thick Elbow

Bend Flexibility Factor Normally bend flexibility factors are calculated according to code requirements. However, the user may override the code calculation by entering a value in the K-factor field. For example, if the user enters 1.5 in this field, the bend will be 1.5 times as flexible as a straight pipe of the same length.

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Reducers

To model reducers use the procedure listed below Modeling Reducers Using CAESAR

Concentric Reducer

Eccentric reducer

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page26 Define the length of the reducer just like any other pipe element. For eccentric reducers be sure to skew the element such that the TO node matches the position of the centerline of the following pipe elements. Double click the Reducer check box on the input spreadsheet. If the element preceding and following the reducer are already defined (such as inserting this element) then CAESAR will automatically calculate all the reducer input data and the user can leave this field blank. Enter the diameter and wall thickness of the pipe that will follow the reducer. Nominal diameter and wall thickness can be entered here and CAESAR will convert these to actual diameter and wall thickness if this portion is activated in the units file (in the Diameter and Wt/Sch fields on the spreadsheet convert nominal to actual then so will the Reducer dialog). Alpha is the slope of the reducer transition in degrees. If left blank, the value will be set from an estimated slope equal to the arc tangent times 1/2 the change in diameters times sixty percent of the entered reducer length.

Tee Pipe Tee is a type of pipe fitting which is T-shaped having two outlets, at 90 to the connection to the main line. It is a short piece of pipe with a lateral outlet. Pipe Tee is used to connect pipelines with a pipe at a right angle with the line. Pipe Tees are widely used as pipe fittings. They are made of various materials and available in various sizes and finishes. Pipe tees are extensively used in pipeline networks to transport two-phase fluid mixtures. There are two types as below Tee Equal Three-port fitting in the shape of a "T". Standard configuration ("Equal") indicates that the straight-through path (typically called the "run") and the perpendicular section ("branch") all have the same size ports. Tee Reducing Typically, this describes a tee fitting in which the branch port is smaller than the ports of the run; it may also include size reduction from one of the run ports to the other. Node no 70 to 200 change the pipe diameter and wall thick.

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Node 70 is the intersection of the 8-in. and 6-in. lines. This intersection is constructed using an 8x6 welding tee. Piping codes recognize the reduced strength of this piping component by increasing the calculated stress at this point in the system. For CAESAR II to include this stress intensification factor in the stress calculation, the node must be identified as a welding tee. First double click the SIFs and Tees check box to activate the SIFs and Tees Auxiliary data area. Specify node 70 as our intersection node and select Welding Tee from the Type drop list. CAESAR II will calculate the SIFs at this intersection according to the piping code selected (B31.3 in this case) so no more input is needed here. Input Items Optionally Effecting SIF Calculations 1 REINFORCED FABRICATED TEE 2 UNREINFORCED FABRICATED TEE 3 WELDING TEE 4 SWEEPOLET 5 WELDOLET 6 EXTRUDED WELDING TEE 7 GIRTH BUTT WELD 8 SOCKET WELD (NO UNDERCUT) 9 SOCKET WELD (AS WELDED) 10 TAPERED TRANSITION

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page28 11 THREADED JOINT 12 DOUBLE WELDED SLIP-ON 13 LAP JOINT FLANGE (B16.9) 14 BONNEY FORGE SWEEPOLET 15 BONNEY FORGE LATROLET 16 BONNEY FORGE INSERT WELDOLET 17 FULL ENCIRCLEMENT TEE This auxiliary screen is used to enter stress intensification factors, or fitting types for up to two nodes per spreadsheet. If components are selected from the drop list, CAESAR

II automatically calculates the SIF values as per the applicable code (unless overridden by the user). Certain fittings and certain codes require additional data as shown. Fields are enabled as appropriate for the selected fitting.

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Rigid (Weight of Rigid elements) Valve & flange The next element (80-90) is the flanged check valve. This CAESAR II element would include the flanged valve and the mating flanges as these piping components are much stiffer than the attached pipe. If the length and weight of this rigid element were known, this data could be entered directly by entering the length in the DY field, enabling the Rigid box and then entering the Rigid Weight in the Auxiliary Data area. Here, for lack of better data and for convenience, the CAESAR II Valve/Flange database will be accessed to generate this input automatically. This data is made available through the Model-Valve menu option or by clicking the Valve/Flange Database button on the toolbar. This command will bring up the window shown below.

Flanged Gate Valve

Butt-weld Gate valve

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page30 Restrains Supports are provided to the piping to resist various loads. The loads can be classified into three categories. They are: primary loads, secondary loads and occasional loads. The response of the piping to various loads is different. The primary load is also known as sustained load. The primary loads are due to the self-weight of the piping, its contents, insulation, refractory, inner casing, outer casing, internal pressure and external pressure. The secondary loads are due to temperature change and relative settlement of foundations. The occasional loads are due to wind, earthquake, water hammer, steam hammer, safety valves blowing jet reactions, surge load, blast load and accidental loads. If the piping is not provided with adequate supports, it will be over-stressed and excessively deform. Over-stressing will cause premature failure. Excessive deformation will impair the performance of the piping.

Anchor +Y Restrains (shoe Support)

o Vertical Pipe Line o Horizontal Pipe Line

Guide o Vertical Pipe Line o Horizontal Pipe Line

Line Stopper ( Axial Stopper) Line Stopper with +Y Restrain Limit stop Limit Stop With + Y Restrain Rod Hanger Spring hanger

o Constant Spring Hanger (CSH) o Variable Spring Hanger (VSH)

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CNode The CNode, or connecting node number, is used only when the other end of the hanger is to be connected to another point in the system, such as another pipe node. ANCHOR An anchor is rigid restraints providing full fixation, i.e., permitting neither translator movement (in X-, Y- and Z- direction) not rotation (around X-, Y- and Z-axis). An anchor provides a fixed reference point of constant position and rotation. Through which effects from the pipe on opposite sides cannot be transmitted. This makes the anchor a convenient terminal point for defining stress analysis problem. A pipe anchor is a rigid support that restricts movement in all three orthogonal directions and all three rotational directions. This usually is a welded stanchion that is welded or bolted to steel or concrete

Anchor Support

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page32 +Y Restrain (Shoe Support) Restraints are provided in the piping primarily to transfer the Sustain loads to the supporting structure. Restraints are usually oriented in any one of the coordinate axes of the plant. Inclined restraints are also used. Usually the restraints are double acting. Struts and ties, which are single acting, are also used. A single acting restraint is a device, which carries only tension or compression.

+Y Restrain ( Shoe Support) +Y Restrain (Shoe Support)For For Horizontal Pipe Line Vertical Pipe Line Guide Support The following are some important facts pertaining to Guides in CAESAR II. Guides are double-acting restraints with or without a specified gap. Guides may be defined using the global system coordinates or with the restraint type GUI. A guided pipe in the horizontal or skewed direction will have a single restraint, acting in the horizontal plane, orthogonal to the axis of the pipe. A guided vertical pipe will have both X and Z direction supports. CAESAR II computes direction cosines for guides. Guide direction cosines entered by the user are ignored.

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Guide Support for Horizontal Pipe Line

Guide with +Y Restrain Support

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Guide Support for Vertical Pipe Line

Axial Stopper (Line Stopper) Translational restraints may be preceded by a (+) or (-). If a sign is entered, it defines the direction of allowed free displacement along the specified degree of freedom. (i.e. a +Y restraint is restraint against movement in the minus Y direction and is free to move in the plus Y direction).

Axial Stopper (Line Stopper) For Horizontal Pipe line

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Axial Stopper (Line Stopper) For Horizontal Pipe line Limit Stops Limit stops are used to limit the stresses in the piping and to reduce the anchor reaction. The behavior of the limit stops is non-linear. The limit stop has zero rigidity up to certain movement. After this predetermined movement, the limit stop comes into action. The active rigidity of the limit stop can be finite or infinite. This depends on the construction of the limit stop.

Limit Stop for Horizontal Pipe Line

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page36 Limit stop for a similar situation in a power plant. There should not be any problem if the pipe stresses are within limits and if the load on the stop is also reasonable. U may be providing this stop to limit the load on some component. The following are important facts pertaining to Limit Stops:

Limit stops are single- or double-acting restraint whose line of action is along the axis of the pipe. The sign on the single-directional restraint gives the direction of unlimited free movement. Limit Stops/Single Directional Restraints can have gaps. The gap is the distance of permitted free movement along therestraining line of action. A gap is a length, and is always positive. Orientation of the gap along the line of action of the restraint is accomplished via the sign on the restraint. Connecting Nodes (CNode) may be used with any Limit Stop model. Limit Stops may be defined using the restraint type LIM. Limit Stops provide double or single-acting support parallel to the pipe axis. Limit Stops may have gaps and friction. The positive line of action of the Limit Stop is defined by the FROM and TO node on the element.

Allowable Support Spans The allowable support span is defined as the maximum permitted unsupported span between any two adjacent supports on a horizontal straight piping. The loads on the piping induce direct stress (axial tension or compression), bending stress, torsion-stress, shear stress and linear and angular deformation. The torsion-stress, shear stress and angular deformation are not usually limited. Popular piping codes limit the bending stress of steel pipes to 15,850 KPa (2,300 psi) and the linear deformation to 2.54 mm (0.1 inch). The suggested pipe support span for commonly used steel piping is given in the following Table. Table Suggested Pipe Support Span NPS inch (DN mm) Water Service m (ft) Steam, gas or air service m (ft) 1 (25) 2.13 (7) 2.74 (9) 2 (50) 3.05 (10) 3.96 (13) 3 (75) 3.66 (12) 4.57 (15)

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4 (100) 4.27 (14) 5.18 (17) 6 (150) 5.18 (17) 6.40 (21) 8 (200) 5.79 (19) 7.32 (24) 12 (300) 7.01 (23) 9.14 (30) 16 (400) 8.23 (27) 10.70 (35) 20 (500) 9.14 (30) 11.90 (39) 24 (600) 9.75 (32) 12.80 (42) For the vertical runs of the pipes, a support span of four times that allowed for horizontal runs can be permitted. It is preferable to avoid providing supports on the pipes inclined in the vertical plane. It is preferable to provide a support at each location of direction change of the pipe.

Hangers Hangers are special types of ties. They are always vertical and carry tensile loads. Rigid Support and Flexible Support

The supports may be rigid or flexible in construction. Flexible supports are used where loads are to be carried, at the same time, accommodate movement. The movements may be due to the thermal expansion of the piping or connected equipment movements. The load variation in the variable load hanger from cold to hot is usually limited to 25%. Variable Load Hanger (VLH) Variable load hanger is a special type of hanger, which accommodate the vertical thermal movements, while carrying the vertical load. Usually variable load hangers are made of helical springs. The load varies from cold condition to hot condition. Constant Load Hanger (CLH) Constant load hanger is a special type of hanger, similar to the variable load hanger. There are several types of constant load hangers. The load variation in the constant load hanger from cold to hot is usually limited to 0%.

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Ten Dos the following leads to a good engineering practice 1. Use minimum number of supports 2. Limit the use of flexible supports 3. Provide supports near the already provided columns and beams 4. Provide necessary clearance for thermal movement 5. Consider all the primary, secondary and occasional loads in the design 6. Provide access for valves and fittings 7. Provide additional loops to satisfy flexibility requirements 8. Provide guides to resist occasional loads like wind and earthquake 9. Provide an ergonomically acceptable design 10. Provide supports for vents, drains, start-up vents and silencers

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Ten Donts avoid the following in design 1. Avoid too many anchors 2. Avoid too long a span 3. Avoid too thin a pipe 4. Avoid large local stresses 5. Avoid too many fittings 6. Avoid too many flexible supports 7. Avoid supports on horizontal bends 8. Avoid supports on pipes inclined to the vertical 9. Avoid bunching of too many pipes 10. Avoid large vertical or horizontal loops VARIABLE LOAD HANGERS SELECTION & SETTING PROCEDURE FOR BOILER AND PIPING APPLICATIONS Scope This procedure deals with the selection and setting of the variable load hangers (VLH) for boiler (pressure parts and non-pressure parts) and piping applications from the presently available list of VLH being manufactured his may be used for pressure vessels and heat exchangers also. General The description, range and type of VLH are described in the write-up on "VARIABLE SPRING HANGERS". The details like selection procedure, shop and site setting informations are described herein. Selection: Before selecting a particular VLH, the designer is advised to acquaint himself/herself with the various aspects of the VLH by perusing the write-up on "VARIABLE SPRING HANGERS". The terminology used in the selection of VLH is indicated in Figure

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SPRING SPRING LOAD COMPRESSION WITH NO LOAD WITH LOAD DIAGARAM (Fully Compressed) Figure A - Pre-compression (initial compression) B - Additional compression in cold condition C - Vertical thermal movement of connected equipment (cold to hot either downward or upward) = Y D - Working range of the VLH E - Unused range of compression

F - Total possible compression G - Additional compression in hot condition H - Free height J - Fully compressed height P - Maximum load carrying capacity of spring-corresponding to a compression of 'F'. Note Figure-1 describes the terminology used in VLH for an application where the

vertical thermal movement of the connected equipment is downward (cold to hot). When the vertical movement from COLD to HOT is upwards, the marks 'COLD POSITION' and 'HOT POSITION' indicated in Figure-1 should be mutually interchanged and following changes in terminology should be effected. B Additional compression in hot condition. G Additional compression in cold condition. Some of the dimensions are constants for all the load groups. They are indicated in Table-1.

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TABLE 1 Sl.No. Dimension Unit TRAVEL RANGE=80 mm TRAVEL RANGE=160 mm 01. A mm 56 112 02. D mm 80 160 03. E mm 24 48 04. F mm 160 320 All other dimensions (B, C & G) are application specific and are to be calculated for each VLH. EXAMPLE: Design load (Hot load) W = 5400 Kg Vertical thermal movement (Cold to Hot) y = 40 mm (downward) (y = c) (When y is less than 1.6 mm, a rigid rod without springs may be used) Try load group '12' and travel range 80 mm. Spring rate (spring stiffness) K = 62.50 Kg/mm Load variation from hot to cold W = K x y = 62.5 x 40 = 2500 Kg W 2500 % load variation = -------- x 100 = --------- x 100 = 46% W 5400 % allowable load variation is 25%, as the actual load variation (46%) is more than the allowable load variation (25%), this selection is not acceptable. (Please note that the allowable load variation is taken as 25% based on ASME-B 31.1, 1992 recommendations. Some customers / consultants specify a lower value of % W, in which case the latter is governing. The tender specifies an allowable load variation of 6% of the cold load). Try load group '12' and Travel Range '160 mm'. Spring rate K = 31.25 Kg/mm

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page42 Ky v 31.25 x 40 x 100 % load variation = -------- x 100 = ------------------------ = 23%

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Please note that the values of B&G should not be outside the range of 0 80 mm and 0 160 mm for VLH with travel ranges: 80 mm and 160 mm respectively. This aspect should be checked for every VLH. When y = 40 mm (upward) W 5400 1 = ----- = ------------ = 172.8 mm K 31.25 2 = 1 - y = 172.8 + 40 = 212.8 mm G = 2 A = 212.8 112 = 100.8 mm B = G y = 100.8 40 = 60.8 mm The values of additional compression in cold condition (B or G) and vertical thermal movement from cold to hot (y = c) are to be communicated to shop / site. Support Thick Calculation The thickness required to take care of the axial tension due to heavy vertical load is given in Equation-1 Do 1 p Do2 2 Do + 4 W T = ------ 1 --------------------- 2 (p + f) Where T = minimum required thickness, mm Do = outside diameter of the pipe, mm p = maximum allowable working pressure, MPa(g) W = axial load, N f = maximum allowable stress in tension, MPa

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page44 Flexible Nozzles

This auxiliary screen is used to describe flexible nozzle connections. When entered in this way, CAESAR II automatically calculates the flexibilities and inserts them at this location. CAESAR II calculates nozzle loads according to WRC 297, API 650 or BS 5500 criteria. When a nozzle node number is input, CAESAR II scans the current input data for the node and loads its diameter and wall thickness and enters it in the Nozzle Auxiliary Data field. Current nozzle flexibility calculations are in accordance with the Welding Research Council Bulletin No. 297, issued August 1984 for cylinder to cylinder intersections. A valid nozzle node has the following properties: Only a single element connects to the nozzle node. The nozzle node is not restrained and does not have displacements specified for any of its degrees of freedom. Computed nozzle flexibilities are automatically included in the piping system analysis via program generated restraints. This generation is completely transparent to the user. Six restraints are established for each flexible nozzle input. If a vessel node number is defined, then the vessel node acts like a connecting node for each of the six restraints. Vessel nodes are subject to the same restrictions shown above for nozzle nodes.

Note: The user should not put a restrainer on an element between the nozzle node and any specified vessel node. CAESAR II creates the required connectivity from the nozzle flexibility data and any user generated stiffnesses between these two points will add erroneously to the nozzle stiffnesses.

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Welding Research Council (WRC-297) WRC-297 can be applied to a larger d/D ratio (up to 0.5) since the analysis is based on a different, thin shell theory (derived and developed by Prof. C. R. Steele). Flexible Nozzle - WRC Bulletin 297 Adhere to these requirements when modeling flexible nozzles Frame only one pipe element into the nozzle node. Do not place restraints at the nozzle node. Do not place anchors at the nozzle node. Do not specify displacements for the nozzle node. (See the following example for displacements at flexible nozzles.)

CAESAR II automatically performs the following functions Calculates nozzle flexibilities for the nozzle/vessel data entered by the user Calculates and inserts restraints to simulate nozzle flexibilities Calculates flexibilities for the axial translations, circumferential, and longitudinal bending Users must perform the error check process to view these calculated values.

CAESAR II uses the following criteria for its calculations Shear and torsional stiffnesses are assumed rigid. Nozzle configurations outside of the WRC 297 curve limits are considered rigid. It is not unusual for one stiffness value to be rigid because of curve limits, and the others to be suitably flexible. The Vessel Temperature and Material fields on the WRC 297 auxiliary data area may be used to optionally compute a reduced modulus of elasticity for the local stiffness calculations.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page46 Nozzle Node Number

Node that is located at the nozzle's intersection with the vessel shell. There should only be a single piping element connected to this node, and there should be no restraints acting on the node. The nozzle element should be perpendicular to the vessel shell. Hillside nozzles and latrolets can still be modeled; however, the first (possibly very short) nozzle element that comes from the vessel should be perpendicular to the vessel to keep the local stiffness properly oriented. The second, longer nozzle element can then go off on the true centerline of the nozzle.

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Vessel Node Number (Optional) Node on the vessel/tank surface at the point where the nozzle intersects the vessel shell. The vessel/tank node is optional, and if not given the nozzle node is connected via the stiffnesses to a point fixed rigidly in space. If the vessel node is given, the nozzle node will be connected via the stiffnesses to the vessel node. Vessel nodes are specified when the user wishes to model through the vessel from the nozzle connection to the skirt or foundation. 3-54 Piping Screen Reference Nozzle Diameter Outside diameter of the nozzle. (Does not have to be equal to the diameter of the pipe used to model the nozzle.) Nozzle Wall Thickness Wall thickness of the nozzle. (Does not have to be equal to the wall thickness of the pipe element used to model the nozzle.)

Vessel Diameter Outside diameter of the vessel. Vessel Wall Thickness Wall thickness of the vessel at the point where the nozzle connects to the vessel. Do not include the thickness of any reinforcing pad. Vessel Reinforcing Pad Thickness Thickness of any reinforcing pad at the nozzle. This thickness is added to the vessel wall thickness before nozzle stiffness calculations are performed. Distance to Stiffener or Head Distance along the vessel center-line, from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel that significantly stiffens the cross-section of the vessel against local deformation normal to the shell surface.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page48 Distance to Opposite-Side Stiffener or Head Distance from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel on the other side of the nozzle. This entry is ignored for spherical vessels. Vessel centerline direction vector X, Y, Z Direction vector or direction cosines which define the center-line of the vessel. For a vertical vessel this entry would read: Vessel centerline direction vector X: Vessel centerline direction vector Y: 1.0 Vessel centerline direction vector Z: Note: The centerlines of the nozzle and vessel cannot be collinear or CAESAR II will flag this as an error.

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Horizontal Vessels Horizontal Vessel models are built using combinations of straight pipe and nozzle flexibility simulations (WRC 297). The following figure illustrates the most accurate way to define horizontal vessel flexibility.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page50 API 650 NOZZLES Activate by double-clicking the Nozzles check box on the Pipe Element Spreadsheet and selecting the API 650 radio button from the Nozzle Auxiliary Data field. Deactivate by double-clicking the check box a second time. CAESAR II can also calculate nozzle flexibilities according to appendix P of API 650, "Design of Carbon Steel Atmospheric Oil Storage Tanks." Nozzle Node Number Node that is located at the nozzle's intersection with the vessel shell. There should only be a single piping element connected to this node, and there should be no restraints acting on the node. The nozzle element should be perpendicular to the vessel shell. Hillside nozzles and latrolets can still be modeled; however, the first (possibly very short) nozzle element that comes from the vessel should be perpendicular to the vessel to keep the local stiffness properly oriented. The second, longer nozzle element can then go off on the true centerline of the nozzle.

Tank Node Number Node on the tank surface at the point where the nozzle intersects the vessel/tank shell. The tank node is optional, and if not given the nozzle node is connected via the API stiffnesses to a point fixed rigidly in space. If the tank node is given, the nozzle node will be connected via the API stiffnesses to the tank node. Tank nodes are specified

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when the user wishes to model through the tank from the nozzle connection to the foundation. Nozzle Diameter Outside diameter of the nozzle. (Does not have to be equal to the diameter of the pipe used to model the nozzle.) Nozzle Wall Thickness Wall Thickness of the nozzle. May be different than the attached pipe wall thickness API-650 Tank Diameter Outside Diameter of the Vessel or API 650 storage tank. Note that API 650 Addendum 1 does not recommend these computations for diameters less than 120 feet. API-650 Tank Wall Thickness Wall Thickness of the Vessel at the point where the Nozzle connects to the vessel. DO NOT include the thickness of any reinforcing pad. API 650 Reinforcing 1 or 2 For API tanks, if the reinforcing is on the shell, then enter 1. If it is on the nozzle, enter a 2. API 650 Nozzle Height For API 650 applications, enter the height from the centerline of the nozzle to the base of the tank. API 650 Fluid Height Enter the liquid level of the fluid in the storage tank. This fluid level must be greater than the nozzle height. API 650 Specific Gravity Enter the specific gravity of the stored liquid. This value is unit less. API-650 Tank Coefficient of Thermal Expansion Enter the coefficient of thermal expansion of the plate material of the tank is constructed. Values are listed in engineering handbooks or the appropriate section of the API 650, App P. If this value is left blank, zero will be assumed. API 650 Delta T

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page52 Enter the change in temperature from ambient to its maximum that the tank normally experiences. For example: If the maximum summertime temperature is 107F. The delta T would be 107 - 70 = 37F. If this value is left blank, zero will be assumed.

API-650 Tank Modulus of Elasticity For API 650 nozzles, the hot modulus of elasticity of the tank must be entered directly. If this value is left blank, 29.5E6 will be assumed. PD 5500 Nozzles Activate by double-clicking the Nozzles check box on the Pipe Element Spreadsheet and selecting the PD 5500 radio button from the Nozzle Auxiliary Data field. Deactivate by double-clicking the check box a second time. CAESAR II can also calculate nozzle flexibilities according to Appendix G of the PD 5500 Specification for Unfired Fusion Welded Pressure Vessels. The input requirements for these nozzles are:

Nozzle Node Number Node that is located at the nozzle's intersection with the vessel shell. There should only be a single piping element connected to this node, and there should be no restraints acting on the node. The nozzle element should be perpendicular to the vessel shell. Hillside nozzles and latrolets can still be modeled; however, the first (possibly very short) nozzle element that comes from the vessel should be perpendicular to the vessel to keep the local stiffness properly oriented. The second, longer nozzle element can then go off on the true centerline of the nozzle.

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Vessel Node Number (Optional) Node on the vessel/tank surface at the point where the nozzle intersects the vessel shell. The vessel/tank node is optional, and if not given the nozzle node is connected via the stiffnesses to a point fixed rigidly in space. If the vessel node is given, the nozzle node will be connected via the stiffnesses to the vessel node. Vessel nodes are specified when the user wishes to model through the vessel from the nozzle connection to the skirt or foundation. Vessel Type - Cylinder (0) or Sphere (1) If the vessel is cylindrical, enter a 0. For cylinders, the distances to stiffeners/heads and the vessel direction cosines are required. If the vessel is spherical, enter a 1. For spheres, the fields for the distances to stiffeners/heads and vessel direction cosines are both ignored. Nozzle Diameter Outside diameter of the nozzle. (Does not have to be equal to the diameter of the pipe used to model the nozzle.) Vessel Diameter Outside diameter of the vessel. Vessel Wall Thickness Wall thickness of the vessel at the point where the nozzle connects to the vessel. Do not include the thickness of any reinforcing pad. Vessel Reinforcing Pad Thickness Thickness of any reinforcing pad at the nozzle this thickness is added to the vessel wall thickness before nozzle stiffness calculations are performed. Distance to Stiffener or Head Distance along the vessel center-line, from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel that significantly stiffens the cross-section of the vessel against local deformation normal to the shell surface. Distance to Opposite-Side Stiffener or Head Distance from the center of the nozzle opening in the vessel shell to the closest stiffener or head in the vessel on the other side of the nozzle. This entry is ignored for spherical vessels. Vessel Centerline Direction Cosines

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page54 These are direction vectors or direction cosines that define the center-line of the vessel. For a horizontal vessel aligned with the X axis, this entry would read: Vessel centerline direction vector X ..... 1.0 Vessel centerline direction vector Y ..... Vessel centerline direction vector Z ..... Note: The centerlines of the nozzle and vessel cannot be co-linear or CAESAR II will flag this as an error. This entry is ignored for spherical vessels. Displacements Activate by double-clicking the Displacements check box on the Pipe Element Spreadsheet. Deactivate by double clicking the Displacements check box a second time. This auxiliary screen is used to enter imposed displacements for up to two nodes per spreadsheet. Up to nine displacement vectors may be entered (load components D1 through D9). If a displacement value is entered for any vector, this direction is considered to be fixed for any other non-specified vectors.

Note Leaving a direction blank for all nine vectors models the system as being free to move in that direction. Specifying 0.0 implies that the system is fully restrained in that direction.

Enter the node number where the displacement is to be specified. There must not be a restraint at this node. Enter the displacements at the node. Any displacement direction not specified for any displacement vector will be free. To specify an anchor at Node 50 with a displacement of 0.25 in. in the +X , 0.10 in. in the +Y , and 0.08 in. in the Z , for displacement vector #1, enter data as shown in the Figure above. The displacements at a node can be specified for up to 9 different vectors, intended to correspond to the 9 temperature cases.

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Note: If an imposed displacement is specified for a specific degree-of-freedom, that degree-of-freedom will be considered restrained for all load cases whether or not they contain that displacement set.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page56 Forces & Movements Activate by double-clicking the Forces/Moments check box on the Pipe Element Spreadsheet. Deactivate by double clicking the check box a second time.

This auxiliary screen is used to enter imposed forces and/or moments for up to two nodes per spreadsheet. Up to nine force vectors may be entered (load components F1 through F9).

Uniform Loads Activate by double-clicking the Uniform Loads check box on the Pipe Element Spreadsheet. Deactivate by double clicking the check box a second time. This auxiliary screen is used to enter up to three uniform load vectors (load components U1, U2 and U3). These uniform loads are applied to the entire current element, as well as all subsequent elements in the model, until explicitly changed or zeroed out with a later entry.

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Wind/Wave This auxiliary screen is used to specify whether this portion of the pipe is exposed to wind or wave loading. (Note that the pipe may not be exposed to both.) Selecting Wind exposes the pipe to wind loading; selecting Wave exposes the pipe to wave, current, and buoyancy loadings; selecting Off turns off both types of loading. This screen is also used to enter the Wind Shape Factor (when Wind is specified) and various wave coefficients (if left blank they will be program-computed) when Wave Loading is specified. Entries on this auxiliary screen apply to all subsequent piping, until changed on a later spreadsheet. Note Specific wind and wave load cases are built using the Static Load Case

Editor. There are three different methods that can be used to generate wind loads on piping systems:

ASCE #7 Standard Edition, 1995 User entry of a pressure vs. elevation table User entry of a velocity vs. elevation table

The appropriate method is selected by placing a value of 1.0 in one of the first three boxes.When defining a pressure or velocity vs. elevation table the user needs to specify only the method and the wind direction on the preceding screen. Upon pressing the User Wind Profile button, the user is prompted for the corresponding pressure or velocity table. If a uniform pressure or velocity is to act over the entire piping system, then only a single entry needs to be made in the table, otherwise the user should enter the pressure or velocity profile for the applicable wind loading. Note To use the ASCE #7 wind loads, all of the fields should be filled in. For example, as per ASCE #7, the following are typical basic wind-speed values: California and West Coast Areas- 124.6 ft. /sec. ( 85 m.p.h.) Rocky Mountains- 132.0 ft. /sec ( 90 m.p.h.)

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page58 Great Plains- 132.0 ft ./sec ( 90 m.p.h.) Non-Coastal Eastern United States- 132.0 ft./sec ( 90 m.p.h.) Gulf Coast- 190.6 ft. /sec (130 m.p.h.) Florida-Carolinas- 190.6 ft./sec (130 m.p.h.) Miami- 212.6 ft. /sec (145 m.p.h.) New England Coastal Areas- 176.0 ft. /sec (120 m.p.h.) Wave Load

Drag Coefficient, Cd Coefficient as recommended by API RP2A. Typical values range from 0.6 to 1.20. Entering a 0.0 instructs CAESAR II to calculate the drag coefficient based on particle velocities. Added Mass Coefficient, Ca This coefficient accounts for the added mass of fluid entrained into the pipe. Typical values range from 0.5 to 1.0. Entering a 0.0 instructs CAESAR II to calculate the added mass coefficient based on particle velocities. Lift Coefficient, Cl This coefficient accounts for wave lift, which is the force perpendicular to both the element axis and the particle velocity vector. Entering a 0.0 instructs CAESAR II to calculate the added lift coefficient based on particle velocities.

Marine Growth The thickness of any marine growth adhering to the external pipe wall. This will increase the pipe diameter experiencing wave loading by twice this value. Marine Growth Density An entry in this field designates the density to be used if including the weight of the marine growth in the pipe weight. If left blank, the weight of the marine growth will be ignored.

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Off This selection turns off both wind and / or wave loads from this point forward in the model. Up to four different hydrodynamic load cases may be specified for any one job. Several hydrodynamic coefficients are defined on the element spreadsheet. The inclusion of hydrodynamic coefficients causes the loads WAV1, WAV2, WAV3, and WAV4 to be available in the load case editor.

A CAESAR II Hydrodynamic Loading dialog is shown in the following figure. In the load case editor, four different wave load profiles can be specified. Current data and wave data may be specified and included together or either of them may be omitted so as to exclude the data from the analysis. CAESAR II supports three current models and six wave models. See the CAESAR II Technical Reference Manual for a detailed discussion of hydrodynamic analysis.

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Kagira Drawing Solution No: 21A, First Floor, Ramalinga Nagar, OMR, Kottivakkam, Chennai-41 Ph: 044 2454 2454, 9500 100900, 9940582828, E-Mail: [email protected],ww.kagira.com Page60 STRESS CATEGORIES The major stress categories are Primary Secondary Peak

PRIMARY STRESSES These are developed by the imposed loading and are necessary to satisfy the equilibrium between external and internal forces and moments of the piping system. Primary stresses are not self-limiting. SECONDARY STRESSES These are developed by the constraint of displacements of a structure. These displacements can be caused either by thermal expansion or by outwardly imposed restraint and anchor point movements. Secondary stresses are self-limiting. PEAK STRESSES Unlike loading condition of secondary stress which causes distortion, peak stresses cause no significant distortion. Peak stresses are the highest stresses in the region under consideration and are responsible for causing fatigue failure. CLASSCIFICATION OF LOADS Primary loads These can be divided into two categories based on the duration of loading. Sustained loads These loads are expected to be present throughout the plant operation. e,g. pressure and weight. Expansion loads These are loads due to displacements of piping. e,g .thermal expansion, seismic anchor movements, and building settlement. Occasional loads These loads are present at infrequent intervals during plant operation. e,g. earthquake, wind, etc. What is flexibility? Flexibility is also a crucial factor in piping system. Train rails illustrate the principle of piping flexibility. Think that the rail ends are squarely fitting, without any gap. When

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the ambient temperature rises, the rails expand. The expansion creates a high force, which can push the joints out of alignment. That is dangerous for the train. That is why we have a small gap between two rails. The rails expand into the gap. No force, no misalignment and all safe. Similarly, pipes are installed during relatively cooler conditions. When a hot fluid passes in the pipe, or when the ambient temperature rises, the pipe expands. The expansion generates enormous force. If only one end of the pipe were connected, the other, loose, end can expand. But generally, in piping both ends are connected. The expansion force acts on equipment or a structure or whatever the pipe is connected to. If it is flexible, the piping system absorbs the expansion and there is no force on to the connected equipment. How to give flexibility? Flexibility can be provided in many ways. The turns and bends that are required for running a pipe from one point to another, by themselves, provide some flexibility. This automatic flexibility may or may not be sufficient. Expansion loops or flexible joints give additional flexibility. Remember, a short pipe requires less capital cost and reduces operating cost, but a short and direct layout is not flexible and cannot absorb thermal expansion. What is an expansion loop? An expansion loop is when some pipe length is perpendicular to the direction of the main pipe run. That

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