Fatigue Design, Verification and Validation of Mechanical Equipment

A​ccess the video recording

This presentation outlines the recommended engineering processes and practices for overall and detailed design to reduce the potential for the occurrence of fatigue cracking damage in operation. Design verification and validation methods are included. Outlined in each step are the actions to be taken, and the standards and reference documents to be followed. This ensures that all defined steps are followed and recorded to deliver a product to address design for fatigue loading. 11 case studies are included.

The presentation details the 3D geometrical form of the equipment, particularly at joints and transitions, which are needed to suitably accept the loading conditions, by providing good structural continuity and load paths in a holistic design manner.

This presentation includes general fatigue design issues and 11 case studies the author has been involved in as principal engineering consultant, summarising what the design shortcomings were, where the fatigue issues occurred, and what the design rectification solutions were. It is trusted that the text will be of use to undergraduate, graduate as well as more senior engineers in bringing good fatigue design practices to the overall design and manufacturing processes.

Fatigue design verification methods are also summarised, specifically in the use of computational finite element methods and correlation of the outputs with the typical fatigue analysis standards BS7608 and the numerous IIW fatigue codes. Iterations of the verification and design process must be completed to result in a fit for purpose design solution of required operational life.

Finally fatigue validation (via strain gauging and vibration monitoring etc) methods are summarised, again along with the iterative use of design / verification / validation actions as may be needed.

The presentation aims to assist engineers to achieve a suitable engineering practice based understanding of the nature of fatigue loadings, how and why they are usually very damaging to mechanical equipment and plant subjected to them, and the design / verification / validation skills and techniques needed to ensure such equipment and plant can withstand these loadings over a suitably long design life. The webinar will not be written from a metallurgy or materials science basis – rather a practical engineering design basis.

Key takeaways

• Gain a practical understanding of the fundamentals of good design, verification and validation processes for fatigue operational conditions across a range of mechanical equipment and plant.
• Learn the nature and application of the critical sequential and iterative steps in the combined fatigue design / verification / validation process so that none are missed, all are applied in the correct order and with the required intensity, so that product function, quality, durability and integrity results.
• Become aware of the nature of fatigue loadings – low cycle, medium/high cycle, cumulative fatigue – rainflow analysis, cycle and damage histograms. Gain exposure to the fatigue design and operational conditions of numerous heavy industry mechanical equipment and plant types, so that such knowledge can be applied in their own day to day design, fabrication, and maintenance activities.

A​bout the presenter

Rob Widders BE (Hons1 Mech USyd), MEngSc (UNSW). Principal Consulting Engineer with global machinery engineering consulting company. 43 years in heavy industry since graduation.

Completion of all mechanical engineering technical and project management activities, hands-on actions in design and analysis, fabrication works and operational site visits, troubleshooting and design rectifications, quality assurance and management, maintenance and repair scopes and planning including turnaround site participation, reporting and technical writing, tendering and proposals, presentation of results and forward plans including budgets, invoicing, office management, guiding and mentoring staff, business development. Projects completed in all states Australia wide as well as NZ, PNG, Indonesia, Fiji, Laos, Korea, China, Germany, Africa, USA and Sweden (including travel to all these locations). Clients have included many mining and mineral processing plants and manufacturers (Alcoa, Ok Tedi, Newcrest, Sino Gold, Sino Iron, Sedgman, Ausenco, Metso, Outotec) and heavy industry (Komatsu, CSR Sugar, ANI Ruwolt, Howden Group, EDI Rail, Nuplex, BOC etc). 1998-2007 Adjunct Senior Lecturer Sydney University Aerospace, Mechanical and Mechatronic Engineering Final Year Mechanical Design course, also supervising many theses students. 2017-21 presented 1st and 4th year professional engineering classes.

Achievements would include;

• Successful completion of heavy industry professional consulting projects globally over 42 years.
• Numerous heavy industry “one-off” troubleshooting and design rectification projects completed globally, of world standard, solving complex mechanical equipment and plant original design and operational problems.
• Initiation of Sydney office of global consulting engineering practice from scratch in 1996, building and taking it to the best performing office in 2005-7.
• Presenting numerous papers to engineering conferences.
• Invited to serve as Adjunct Senior Lecturer Sydney University Aerospace, Mechanical and Mechatronic Engineering Final Year Mechanical Design course 1998-2007, also supervising many theses students. 2017-21 presented 1st and 4th year professional engineering classes. Participated in three AMME reviews the last 2017.

Postnominals: BE (Hons1 Mech USyd), MEngSc (UNSW).
1980-2018 – Fellow of the Institution of Engineers, Australia. Member of the Mechanical College, CPEng, NER.
2014 to 2018 – Registered Professional Engineer of Queensland (RPEQ).
1996 to June 2008 – Fellow of the Royal Institution of Naval Architects.