ASME Design by Analysis

Delegates will learn how to evaluate their designs to protect against the plastic collapse failure mode by utilising results from a stress analysis. Three alternative methods are presented, covering development of appropriate finite element models, categorisation of various loading conditions and the interpretation of the results using techniques such as stress linearisation.

Failure due to static loading is the primary focus of this course, but a brief overview of failure modes such as buckling, fatigue, and ratcheting will also be presented. This course focuses on the Design by Analysis methods from ASME BPVC Section VIII Division 2 as a basis for assessment. Following completion of this course, alternative codes which have similar assessment techniques, such as BS EN 13445 or PD5500, can be easily adopted.

Whilst these codes are for the design of boilers and pressure vessels, the techniques, principles and assessment methods learnt can be applied to any other industry and structure. On completing this course, delegates will become familiar with the core concepts of Design by Analysis and how these techniques can be applied to assess the structural integrity of their own designs.

Module 1 – Introduction to ASME BPVC

Introducing the ASME BPVC focusing on Part 5 - ‘Design by Analysis’. This part of the code provides a foundation for ensuring against the plastic collapse failure mode using simulation techniques.

Module 2 – General FEA Procedures

A brief overview of the key considerations when developing FE models for relevant Design by Analysis methods. This includes the type of analysis, material definitions, interface treatments (contacts), types of elements, non-linear stiffness behaviour and the application of loads and restraints.

Module 3 – Material Properties

Accurate definition of the materials and how they behave under load is an important aspect of analysis. Extracting data from ASME Section II Part D will be demonstrated including temperature considerations.

Module 4 – Elastic Stress Analysis Method (ESAM)

Using linear elastic material behaviour, learn how to linearise stresses to identify stress categories such as membrane, bending and peak stresses. Use these stress categories to assess against plastic collapse.

Module 5 – Limit Load Analysis Method (LLAM)

Using elastic-perfectly plastic material behaviour, applied forces are increased until the point of failure i.e. plastic collapse. This information will used to define a limiting load factor.

Module 6 – Elastic-Plastic Analysis Method (EPAM)

Using elastic-plastic material behaviour, applied forces are increased until the point of failure i.e. plastic collapse. This approach is the most accurate method of assessment but the most challenging to solve. All three methods will be compared to demonstrate which approach should be used, and when.

Module 7 – Other Sections of Design by Analysis

Assessment of other failure modes are briefly introduced – local failure, fatigue, buckling and ratcheting.