Recent Posts

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

Calculation of Thrust Block Loads for GRE Pipeline Systems

Written by Kourosh Mashayekh in Piping Stress Basics

A thrust block in a GRE (Glass Reinforced Epoxy) pipeline system is a concrete support structure designed to resist the forces generated by internal pressure and changes in flow direction. It prevents the pipeline from moving, separating at joints, or becoming damaged due to hydraulic thrust.

Why is a thrust block required?

When fluid flows through a pressurized GRE/GRP pipeline, it generates forces at certain locations, particularly where the flow direction or pipe geometry changes.

Typical locations requiring thrust blocks include:

  • Bends: 45° and 90° elbows.
  • Tees and branches: Where the flow divides or branches off.
  • Reducers: Where the pipe diameter changes.
  • Dead ends and end caps: Where the pipeline terminates.
  • Valves: Where pressure forces may act on the pipeline, depending on the arrangement.

How does a thrust block work?

A thrust block transfers the hydraulic force from the pipe fitting into the surrounding soil.

For example, when water flows through a 90° bend, the pressure creates an unbalanced force that tends to push the bend away from its position. A concrete thrust block is constructed behind the bend and bears against firm, undisturbed soil to resist that force.

The load path is:

Water pressure → GRE fitting → Thrust block → Surrounding soil

Calculation of Thrust Block Loads for GRE Pipeline Systems

As mentioned earlier, Thrust Blocks (TBs) are structural elements designed to restrict axial movement of pipelines. Consequently, axial elongation resulting from internal pressure and thermal expansion is resisted by a longitudinal force. This resistance acts to compress the pipe back to its original position, and the corresponding reaction force is the load transferred to the thrust block.

To accurately evaluate loads on a horizontal TB, the analyst must first assess the axial elongation induced by internal pressure and thermal expansion. Subsequently, the required force (R) necessary to produce the same amount of elongation is calculated. The force transferred to the TB depends on both the magnitude of R and elbow angle (θ).

The Axial Elongation due to internal pressure is as follows:

For composite materials such as GRE pipes:

So:

The Axial Elongation due to thermal expansion is as follows:

* It is assumed that the thermal expansion in the hoop direction is negligible and does not contribute significantly to the overall deformation of the pipe.

The difference between the manual calculations and the results obtained using CAESAR II is less than 2%, indicating a high level of consistency and validating the accuracy of the analytical approach.

Symbols & Abbreviations

Ac: Cross-sectional area of pipe

Ai: Inner area of pipe

Dmean: Mean diameter of pipe

Ea: Axial elastic modulus of pipe

Eh: Hoop elastic modulus of pipe

ID: Inside diameter of pipe

K: Factor to compensate for the thermal effects of process liquid (BS 7159)

L: Length of the pipeline

OD: Outside diameter of pipe

Pi: Internal pressure

R: Resisting force

RP: Resistance force due to internal pressure

RTh: Resistance force due to thermal expansion

RTotal: Total resistance force

T: Total load on thrust block

TB: Thrust block

Tdes: Design temperature

Tins: Installation temperature

TP: Load on thrust block due to internal pressure

TTh: Load on thrust block due to thermal expansion

THK.: Wall thickness of pipe

α: Thermal expansion coefficient of GRE

ΔL: change in length

ΔT: Change in temperature

εa: Axial elongation

εap: Axial elongation due to internal pressure

εaTh: Axial elongation due to thermal expansion

σ: Stress

σap: Axial stress due to internal pressure

σh: Hoop stress

σat: Axial stress due to thermal expansion

θ: Elbow angle

Va/h: Poisson’s ratio of the strain in the axial direction resulting from a stress in the hoop direction

Vh/a: Poisson’s ratio of the strain in the hoop direction resulting from a stress in the axial direction

Results of CAESAR II:

Important considerations for GRE pipelines

GRE/FRP pipes differ from steel pipes because they are composite materials and may use bonded, laminated, or elastomeric joint systems. Therefore:

  • Do not assume that the pipe joints can resist axial thrust unless the joint system is specifically designed for it.
  • Ensure the thrust block bears on suitable soil rather than loose backfill.
  • Avoid applying concentrated loads directly to the GRE pipe wall.
  • Provide suitable clearance and bearing arrangements around the fitting in accordance with the manufacturer’s requirements.
  • Check whether the pipeline design uses concrete thrust blocks, restrained joints, or another engineered thrust-resisting arrangement.

In simple terms: A thrust block is a concrete anchor behind a pipeline fitting that stops water pressure from pushing the fitting or pipe out of position.

References

  • AWWA M45: Fiberglass Pipe Design, 4th Edition
  • UKOOA: SPECIFICATION AND RECOMMENDED PRACTICE FOR THE USE OF GRP PIPING OFFSHORE
  • BS 7159: British Standard Code of practice for Design and construction of glass reinforced plastic (GRP) piping systems for individual plants or sites

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.