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Advanced Pipe Stress Analysis (Caesar II) Online Pre-Recorded Course (30+ hours)

Written by Anup Kumar Dey in Piping Stress Analysis

Whatispiping Team, in association with Everyeng, is conducting an online pre-recorded Comprehensive Piping Stress Analysis Certificate course to help mechanical and piping engineers. Along with the regular content that the participants will be learning, there will be a dedicated 1-hour doubt-clearing session (/question-answer session) with the mentor.

Contents of Online Piping Stress Analysis with Caesar II Course

The program will be delivered using the most widely used pipe stress analysis software program, Caesar II. The full course is divided into 4 parts.

  • Part A will describe the basic requirements of pipe stress analysis and will help the participants to be prepared for the application of the software package.
  • Part B will describe all the basic static analysis methods that every pipe stress engineer must know.
  • Part C will give some understanding of the dynamic analysis modules available in Caesar II; and
  • Part D will explain all other relevant details that will prepare a basic pipe stress engineer to become an advanced user. Additional modules will be added in this section as and when ready.
Comprehensive Piping Stress Analysis Online Course

In its present form, the full course will roughly cover the following details:

Part A: Basics of Pipe Stress Analysis

  • What is Pipe Stress Analysis?
  • Stress Critical Line List Preparation with Practical Case Study
  • Inputs Required for Pipe Stress Analysis
  • Basics of ASME B31 3 for a Piping Stress Engineer
    • ASME B31.3 Scopes and Exclusions
    • Why stress is generated in a piping system
    • Types of Pipe Stresses
    • Pipe Thickness Calculation
    • Reinforcement Requirements
    • ASME B31.3 Code Equations and Allowable
  • Introduction to Pipe Supports
    • Role of Pipe Supports in Piping Design
    • Types of Pipe Supports
    • List of Pipe Supports
    • Pipe Support Span
    • How to Support a Pipe?
    • Pipe Support Optimization Rules
    • Pipe Support Standard
    • Support Engineering Considerations
  • What is a Piping Isometric?
  • What is an Expansion Loop?
  • Various Bonus Lectures like Introduction to Pipe Stress, Pressure Stresses in Piping, Radial Stresses in Piping, Material Stresses in Piping, etc.

Part-B: Static Analysis in Caesar II

  • Introduction to Caesar II
  • Getting Started in Caesar II
  • Stress Analysis of Pump Piping System
  • Creating Load Cases
  • Wind and Seismic Analysis
  • Generating Stress Analysis Reports
  • Editing Stress Analysis Model, Trunnion Modelling
  • Spring Hanger Selection and Design in Caesar II
    • Introduction
    • Types of Spring Hangers
    • Components of a Spring Hanger
    • Selection of Variable and Constant Spring hangers
    • Case Study of Spring Hanger Design and Selection
    • Certain Salient Points
  • Flange Leakage Analysis in Caesar II
    • Introduction
    • Types of Flange Leakage Analysis and Background Theory
    • Case Study-Pressure Equivalent Analysis
    • Case Study-NC Method
    • Case Study-ASME Sec VIII method
  • Stress Analysis of PSV Piping System
    • Introduction
    • PSV Reaction Force Calculation
    • Applying PSV Reaction force
    • Practical Case Study
    • Certain best practices
  • Heat Exchanger Pipe Stress Analysis
    • Introduction
    • Creating Temperature Profile
    • Modeling the Heat Exchanger
    • Nozzle Load Qualification
    • Practical Case Study
    • Methodology for shell and tube inlet nozzle stress analysis
  • Vertical Tower Piping Stress Analysis
    • Introduction
    • Creating Temperature Profile
    • Equipment Modeling
    • Modeling Cleat Supports
    • Skirt temperature Calculation
    • Nozzle Load Qualification
    • Practical Example
  • Storage Tank Piping Stress Analysis
    • Introduction
    • Reason for Criticality of storage tank piping
    • Tank Settlement
    • Tank Bulging
    • Practical example of tank piping stress analysis
    • Nozzle Loading
  • Additional Bonus modules on Pump Piping Stress Analysis
    • API610 Pump nozzle evaluation using Caesar II

Part C: Dynamic Analysis is Caesar II

  • Introduction-Dynamic Analysis in Caesar II
  • Types of Dynamic Analysis
  • Static vs Dynamic Analysis
  • Dynamic Modal Analysis
  • Equivalent Static Slug Flow Analysis
  • Dynamic Response Spectrum Analysis

Part D: Miscellaneous other details

  • WRC 297/537 Calculation
    • What are WRC 537 and WRC 297?
    • Inputs for WRC Calculation
    • WRC Calculation with Practical Example
  • Underground Pipe Stress Analysis
  • Jacketed Piping Stress Analysis
  • Create Unit and configuration file in CAESAR II
  • ASME B31J for improved Method for i, k Calculation in Caesar II
  • Discussion about certain Questions and Answers
  • GRE/FRP Pipe stress analysis
    • GRE Pipe Stress Analysis using Caesar II
    • GRE Stress Analysis-Basics
    • FRP Pipe Stress Analysis Case Study
    • GRE Flange Leakage Analysis
    • Meaning of Stress Envelope; Understand it
  • Reviewing A Piping Stress System
    • Introduction
    • What to Review
    • Reviewing Steps
    • Case Study of Reviewing Pipe Stress Analysis Report
    • Reviewing Best Practices
  • FIV Study
    • Flow Induced Vibrations-Introduction
    • What is Flow-Induced Vibration (FIV)?
    • Flow-Induced Vibration Analysis
    • Corrective-Mitigation Options
  • AIV Study
    • Introduction
    • What is Acoustic-Induced Vibration (AIV)?
    • Acoustic-Induced Vibration Analysis
    • Corrective-Mitigation Options
  • Basics of Expansion Joints
    • Introduction-Expansion Joints
    • Basics of Expansion Joints
    • Types of Expansion Joints
    • Application Engineering
    • Design Considerations for Expansion Joints
    • Single Expansion Joint Modelling in Caesar II
  • Basics Theory of HDPE Pipe Stress Analysis
  • Various Bonus modules on Interview Questions, Jacketed Piping System Stress Analysis, Stress Intensification Factor, etc.

How to Enroll for this Course

To join this course, simply click here and click on Buy Now. It will ask you to create your profile, complete the profile, and make the payment. As soon as the payment is complete, you will get full access to the course. If you face any difficulty, contact the Everyeng team using the Contact Us button on their website.

Detailed Online Course on Pipe Stress Analysis (25 hours of Content) with Certificate + Free Trial Version of Pipe Stress Analysis Software

Written by Alex Matveev in Engineering Courses,Pipeline,Piping Design Basics,Piping Stress Analysis,Piping Stress Basics,Start-Prof

This course is created by an experienced pipe stress analysis software developer (15+ years experience), Ph.D. and covers all features of onshore above ground and underground piping and pipeline analysis. This course is based on the PASS/START-PROF software application, though it will be interesting for users of any other pipe stress analysis software tools as it contains a lot of theoretical information.

The course consists of video lectures, quizzes, examples, and handout materials.

Type: an on-demand online course.

Duration: 25 hours.

Course price: 200 USD 30 USD.

Instructor: Alex Matveev, head of PASS/START-PROF Pipe Stress Analysis Software development team. Always available for your questions at Udemy, LinkedIn, Facebook

Alex Matveev

Who should attend

All process, piping, and mechanical engineers specialized in design and piping stress analysis for the specified industries:

  • Oil & Gas (Offshore/Onshore)
  • Chemical & Petrochemical
  • Power (Nuclear/ Non-Nuclear)
  • District Heating/Cooling
  • Water treatment
  • Metal industry

Training software

All trainees are provided with a free 30-day pipe stress analysis software license (PASS/START-PROF). How to get a free license

Certificate

After finishing the course, you will receive Certificates from both the Udemy and from PASS Team.

Detailed Training Agenda: Download the detailed training agenda in PDF.

Brief Summary of the Course

Introduction
Section 1. Working with PASS/START-PROF User Interface339 min
Section 2. Piping Supports138 min
Section 3. Stress Analysis Theory and Results Evaluation237 min
Section 4. Underground Pipe Modeling249 min
Section 5. Static and Rotating Equipment Modeling and Evaluation244 min
Section 6. Expansion Joints, Flexible Hoses, Couplings106 min
Section 7. Non-Metallic Piping Stress Analysis99 min
Section 8. External Interfaces65 min
Brief Course Summary

How to Enroll for the Course

Visit the Pipe Stress Analysis course page on Udemy

Then click Add to Cart or Buy Now and follow the instructions

What you will learn in this Course

  • Pipe stress analysis theory. Load types. Stress types. Bourdon effect. Creep effect in high-temperature piping, creep rupture usage factor (Appendix V B31.3)
  • ASME B31.1, ASME B31.3, ASME B31.4, ASME B31.5, ASME B31.8, ASME B31.9, ASME B31.12 code requirements for pipe stress analysis
  • How to use PASS/START-PROF software for pipe stress analysis
  • How to work with different load cases
  • How to model different types of piping supports, the spring selection
  • What are stress intensification and flexibility factors and how to calculate them using FEA and code requirements
  • How to model trunnion and lateral tees
  • How to model pressure vessels and columns connection: modeling local and global flexibility, WRC 297, WRC 537, FEA
  • How to model storage tank connection (API 650)
  • How to model connection to air-cooled heat exchanger API 661, fired heater API 560, API 530
  • How to model connection to Pump, Compressor, Turbine (API 610, API 617, NEMA SM23)
  • How to model buried pipelines: Submerged Pipelines, Long Radius Bends Modeling of Laying, Lifting, Subsidence, Frost Heaving, Fault Crossing, Landslide
  • Underground pipelines Seismic Wave Propagation, Pipe Buckling, Upheaval Buckling, Modeling of Pipe in Chamber, in Casing with Spacers. Electrical Insulation kit
  • Minimum design metal temperature calculation MDMT calculation, impact test
  • Modeling of Expansion Joints, Flexible Hoses, Couplings
  • Import and export to various software: CAESAR II, AVEVA, REVIT, PCF format, etc.
  • How to do Normal Modes Analysis and how to interpret results
  • ASME B31G Remaining Strength of Corroded Pipeline Calculation

Interview Questions for Compressor Piping Stress Analysis using Caesar II

Written by Anup Kumar Dey in Piping Stress Analysis

Compressor piping stress analysis is the engineering process of checking whether the piping connected to a compressor can safely withstand the forces, moments, movements, and vibrations that occur during operation.

The key concern is that piping must be flexible enough to absorb thermal movement, but stiff enough to avoid excessive loads on the compressor nozzles and supports.

Why perform Compressor Piping Stress Analysis?

A compressor is relatively sensitive to piping loads. If the connected piping is poorly designed, it can transmit excessive forces or moments to the compressor nozzle, potentially causing:

  • Compressor nozzle deformation
  • Shaft/coupling misalignment
  • Excessive vibration
  • Leakage at flanges
  • Pipe/support failures
  • Excessive pipe stresses
  • Fatigue or fatigue cracking
  • Problems during startup/shutdown

Interview Questions for Compressor Piping Stress Analysis

Here are some of the important questions related to compressor piping (both centrifugal and reciprocating) stress analysis that every advanced pipe stress engineer should prepare.

Compressor Piping Stress Analysis Questions Set 1:

  1. Explain the terms blade pass frequency and rotating stall with respect to centrifugal compressors. Compare these two phenomena. Do they affect piping system vibration? If yes, how?
  2. Explain the roles of the lines connecting suction and discharge for reciprocating and centrifugal compressors with reference to the key valves on these lines and their roles in piping vibration.
  3. In the design stage, what are the key things that a pipe stress engineer can do to minimize in-service vibration in piping systems connected to centrifugal compressors?
  4. Explain how to identify aerodynamic and mechanically induced vibrations in centrifugal compressor piping systems in FFT and orbit plots.
  5. A centrifugal compressor piping system has issues with different settlement issues with respect to an adjacent support. Share your thoughts on how to minimize the effect of this differential settlement.
  6. Write briefly about the importance of maintaining a required free end displacement during alignment of a reciprocating compressor piping system with the compressor nozzle. Explain the merits and demerits of checking this with springs in locked and unlocked conditions. State the industry standard you can refer to for “not to exceed values”.
  7. Explain what is meant by largest nozzle in the language of API 617 Appendix F.
  8. Explain the checks required for nozzle loads as per API 617. What is meant by 1.85 times NEMA SM 23?
  9. Explain the difference between double-acting and 2-throw reciprocating compressors.
  10. What are the typical geometrical arrangements in two- and three-throw reciprocating compressors? Explain the number of pulsations per cycle. How will you find out which of these pulsations generate pulses that are in-phase, and which are out-of-phase? Explain your answer.
  11. Explain the difference between design approach 2 and 3  w.r.t. API 618. How to decide which approach you need to use for a particular compressor.
  12. Explain the purpose of a pulsation study in the context of reciprocating compressors as per API 618.
  13.  Briefly explain the equations that go into a pulsation study.
  14. Explain harmonic analysis in CAESAR II. How is phase calculated? Explain the significance of the following:
Compressor Piping Stress Analysis

Compressor Piping Stress Analysis Questions Set 2:

  1. Explain the drawbacks and cautions of a CAESAR II-based analysis for reciprocating compressor piping systems.
  2. What is a mode of vibration, and explain the difference between an acoustic and structural mode. Explain the meaning of the term standing waves and the relationship between standing waves and modes of vibration (in the context of both acoustic and structural modes)
  3. Explain the key outputs of a pulsation study and the limitations on pulsation levels in pulsation suppression devices and piping systems as per API 618. Explain the limitations imposed by API 618 on pressure drop and shaking forces.
  4. What is meant by resonant and non-resonant conditions in API 618? How is non-resonant quantified?
  5. Is it necessary to model compressor cylinders in CAESAR II? How to model pulsation dampers in CAESAR II?
  6. Write a brief note on arriving at a scope of work for a pulsation study and state the reasons for the same.
  7. Explain some designs used to suppress pulsation in reciprocating compressor systems. What are the key aspects in designing such supports? What information is required?
  8. Explain the term narrow band, broad band, and white noise in the context of random vibrations. How to identify them? Explain in the context of AIV, FIV, vortex-induced vibration, and vibration of reciprocating compressor piping systems.
  9.  Explain in detail the extent of analysis required to make sure that pulsation levels attenuate by those lengths. How to have a rough estimate of the length and how to arrive at diameter or area ratios which successfully reduce amplitude of vibration.
  10. Explain the concept of volume-choke-volume pulsation dampers and what is meant by Helmholtz frequency. Explain. Giving reasons, the roles of volume and choke and the significance of the term acoustic mass. Why do we refer to the small amount of physical mass in the choke as having high acoustic mass?
  11. Explain allowable vibration requirements from API 618. Are they for in-service vibration? If not, what documents can you use for in-service vibration?
  12. Explain how a viscous damper works.

Answers to Compressor Piping Stress Analysis Interview Questions

Are you looking for the answers? You can enroll in the following online course that will help you resolve most of the above questions and reinforce your learning of compressor piping stress analysis.

The above course covers the basics of pipe stress analysis for both centrifugal and reciprocating compressor piping systems.

Maximum Allowable Internal Pressure of Pipe Bends

Written by Kourosh Mashayekh in Piping Design Basics

A pipe bend in the oil and gas industry is a curved section of piping used to change the direction of fluid flow, typically by 45° or 90°. Pipe bends are designed to withstand high pressure, temperature, and mechanical stresses while maintaining smooth and efficient flow. They are commonly used in pipelines, process plants, refineries, and other piping systems to route fluids around equipment and structures.

The following article will explain the maximum allowable internal pressure capabilities for pipe bends used in the oil and gas industries.

Two types of bends are quite common in the oil and gas industries. Normal pipe bends as a pipe fitting and mitre bends.

1. Pipe Bends and Elbows

Minimum Required Wall Thickness (tm) of Pipe Bends

While the concept of calculating the tm (t+c) of pipe bends is similar to the calculation of pipe wall thickness, the designer shall consider the “I” factor for the intrados and extrados of the bend as follows, as per ASME B31.3:

First, it is shown what the factor “I” is. Then, the effect of this factor on the maximum allowable internal pressure (Pm) of pipe bends is evaluated.

Figure 1 illustrates a simple bend under Internal Pressure (Pi). As shown, a radial pipe segment is divided into two zones: the inside zone is shown in yellow, and the outside zone is shown in black.

Pressure Stress at Bend
Figure 1. Pressure Stress at Bend

The Pi acts on the area named Ai and Ae, while the hops stress (Sh) acts on the A1 and A2, as shown in Figure 2.

Pressured Stress at a radial Pipe Segment
Figure 2. Pressured Stress at a radial Pipe Segment

Thus:

At the intrados of pipe bend:

At the extrados of pipe bend:

By comparing Equations 8 and 9 together, it is clear that the required THK. of a pipe bend at the intrados is greater than the required value at the extrados of the bend. Thus, ASME B31.3, ASME NM.1, and ASME NM.2 consider the Pm at the intrados of pipe bends. If Eq. 2 is simplified, we have:

Where R is the bend radius of the welding elbow or pipe bend, and r is the radius of pipe. It should be noted that ASME NM.2 replaces I with m in Equations 2-3-7 and 2-3-8.

To evaluate Pm, with respect to Equations 9 and 10, we have:

Based on Eq. 11, for FRP pipes (ASME NM.2, Eq. 2-3-10) and HDPE pipes (ASME NM.1, Eq. 2-3-7):

For steel pipe bends, as per ASME B31.3 [Eq. (4b)], the designer shall consider the effects of the factors E and W, and replace the t by (T-c). Thus:

Where:

E is the quality factor.

W is the weld joint strength reduction factor.

c is the sum of the mechanical allowances.

T is the wall thickness of pipe bend.

2- Miter Bends

Sometimes mitered pipe ends are connected together to make a change in the direction of piping. These mitered connections are known as mitered bends. Here, it is shown when a miter bend requires design consideration and what the requirements are.

Some standards, codes, and studies state that if the angular offset is 3 degrees or less, there is no need for any design consideration as mitered bend. For instance:

  • ASME B31.3-2022, Clause 304.2.3: An angular offset of 3 degrees or less (angle α in Figure 3) does not require design consideration as a miter bend.
  • ASME NM.1-2018, Clause 2-3.2.4, Section (e): Mitered joints of 3 degrees or less shall not require redesign consideration as mitered elbows.
  • Dynaflow Research Group, “Finite Element Analysis of Filament Wound Pipe Coupler”

    *It should be noted that other standards or codes may specify other requirements.
Nomenclature for Miter Bends
Figure 3 Nomenclature for Miter Bends

As the pipe direction changes, the geometry changes. Therefore, in this case, the effects of the discontinuity area and, subsequently, the discontinuity stresses on the pipe and mitered elbow shall be evaluated.

As shown in the relevant discontinuity stress post, the effective zone is a key parameter in discontinuity areas. It is good practice to consider βX=1, where the magnitude of shear stress decreases to less than 20% of its maximum value. Thus:

According to Figure 4, the hatched area is the smallest existing area in a mitered elbow, and therefore, it is more vulnerable than other areas to internal pressure. Therefore, the design criteria shall ensure that this area can resist Pi.

Figure 4

The Reaction Force (F) acts on the Area of “abgh” as shown in Figure 4, and its area is as follows:

Where:

t is the wall thickness of the pipe

Multiple Miter Bend or Single Miter Bend with Q not larger than 22.5°:

To avoid failure of the miter elbow, Pm shall be calculated as follows:

If the numerator and denominator of the fraction are multiplied by t, then:

Now, if the “t” and “r” are replaced with “T-c” and “r2”, respectively, then we have:

This is the mentioned Equation (4a) of ASME B31.3, Where:

T is the miter pipe wall thickness

r2 is the mean radius of the pipe

c is the sum of mechanical allowances

FRP pipes (Eq. 18) have no W and E factors, and if r is replaced with r2 in that equation, the Pm for FRP miter bends will be as follows:

The above equation is Eq. (2-3-9) of ASME NM.2.

It should be mentioned that for polyethylene (PE) pipes, the long-term Poisson ratio is 0.45. If this value is used, the equation 14 will be:

By considering the new value of x in the above equations, Equation 20 will be as follows:

The above equation is the referenced Equation (2-3-6) of ASME NM.1.

Equations 19, 20 and 22 are the criteria of the maximum allowable internal pressure of miter bends for steel, FRP, and HDPE pipes, respectively. While these criteria determine the Pm for miter bends, the value of Pm shall not be greater than the maximum allowable internal pressure of pipe bends (equations 12 and 13).

Single Miter Bend with θ larger than 22.5°:

ASME NM.2 and ASME B31.3 choose a more conservative approach for single miter bends with θ greater than 22.5 degrees. They almost double the 0.643 value and increase it to 1.25.
Therefore, Pm for a single miter bend as per ASME B31.3 (Eq. 4c) and ASME NM.2 (Eq. 2-3-11) is, respectively, as follows:

It should be noted that ASME NM.1 limits the angle θ to 22.5 degrees.

Effective Length of the Miter-Bend Discontinuity (M)

It should be mentioned that the required thickness of steel and FRP miter bends shall be continued for an adequate distance, where the effects of discontinuity could be neglected. This distance is called “M” in ASME B31.3 and ASME NM.2. According to Figure 3, M is as follows:

Based on Figure 5 of the post “What is Discontinuity Stress with respect to Pipe Stress analysis?”, when βX=3.2, the values of shear force and bending moment are less than 95% of their maximum values. Thus, it is an acceptable distance for M:

This is the referenced criterion in “ASME B31.3, para. 304.2.3, Clause (c)”, and “ASME NM.2, para 2-3.3.2, Clause (c)”.

References

  • 1- ASME B31.3: Process Piping Code
  • 2- ASME NM.1: Thermoplastic Piping Systems
  • 3- ASME NM.2: Glass-Fiber-Reinforced Thermosetting-Resin Piping Systems
  • 4- AWWA M55: PE Pipe – Design and Installation
  • 5- “Pipe Stress Engineering” – L.C. Peng and T.L. Peng
  • 6- “Finite Element Analysis of Filament Wound Pipe Coupler” – Dynaflow Research Group