Forensic Engineering: The Art and Craft of A Failure Detective

Forensic Engineering: The Art and Craft of a Failure Detective synthesizes the current academic knowledge, with advances in process and techniques developed in the last several years, to bring forensic materials and engineering analysis into the 21st century. The techniques covered in the book are applied to the myriad types of cases the forensic engineer and investigator may face, serving as a working manual for practitioners. Analytical techniques and practical, applied engineering principles are illustrated in such cases as patent and intellectual property disputes, building and product failures, faulty design, air and rail disasters, automobile recalls, and civil and criminal cases. Both private and criminal cases are covered as well as the legal obligation, requirements, and responsibilities under the law, particularly in cases of serious injury or even death. Forensic Engineering will appeal to professionals working in failure analysis, loss adjustment, occupational health and safety as well as professionals working in a legal capacity in cases of produce failure and liability—including criminal cases, fraud investigation, and private consultants in engineering and forensic engineering.

Table of Contents:
I Preface II Contents III Acknowledgements Chapter 1 Failure analysis or forensic engineering? 1.0 Synopsis 1.1 Historic failure analysis 1.2 Conventional failure analysis 1.3 Product defects 1.4 Causal Analysis 1.4.1 Computer aided causal analysis 1.4.2 Case Study: wear markings as ‘fingerprints’ 1.5 Design calculations and modelling 1.5.1 Miner’s Law for life time cumulative damage prediction 1.6 Summation of conventional failure analysis 1.7 Forensic engineering 1.7.1 Case Study: Collapse of the Rana Plaza factory 1.8 Range of competence 1.8.1 A generic failure analysis or a forensic investigation? 1.9 Forensic approach to failure 1.9.1 Reverse engineering 1.9.2 Associated costs of forensic investigation 1.10 Historic failures 1.10.1 Computer-aided technology limitations 1.11 Analytical techniques 1.12 Dissemination of knowledge and experience 1.12.1 Popular books 1.12.2 Event reporting 1.12.3 Text books 1.12.4 Forensic engineering teaching 1.13 Case study themes 1.13.1 The Sayano-Shushenskaya power station accident of 2009 1.14 Research enriched teaching 1.15 Concluding remarks 1.16 References Chapter 2 Initial aspects of forensic failure investigation Introduction 2.1 Three essential ‘abstract’ assets for the investigator 2.1.1 Assessing the situation 2.1.2 Initial visual observation as a fact-finding exercise 2.1.3 The failure scenario 2.1.4 Summary of understated investigative skills 2.2 Visual observation 2.2.1 Case study: visual comparison 2.2.2 Case study: common (engineering) sense 2.3 Forensic photography 2.4 Record keeping 2.5 Witness evidence 2.6 Documentary evidence 2.6.1 Case study: Fatal aircraft crash 2.7 Product and material standards 2.7.1 Case study: Step ladder accident 2.8 Patents 2.9 Surviving remains (detritus) 2.9.1 Gathering of evidence and the ‘Chain of Evidence’ 2.10 Product liability 2.10.1 Case study: Premature failure of a presentation cake knife 2.11 The ‘Corporate’ environment 2.11.1 Case study: Bird-strike testing of aircraft engines 2.12 Abuse or misuse 2.12.1 Case study: abuse 2.12.2 Case study: miss-use 2.13 References Chapter 3 A framework or methodology for forensic investigation Introduction 3.1 Background to failure analysis methodology 3.2 An investigative path followed by the writer 3.2.1 Intuition (reasoning) and a ‘structured’ investigation framework 3.2.2 Individual stages of investigation 3.2.3 The field investigation kit 3.2.4 Initial approach to failure investigation 3.2.5 Background data collection 3.2.6 Sifting the evidence 3.2.6.1 Case study: Failure of a new design of horse bit 3.2.7 Records 3.2.8 Single items of evidence 3.3 The failure detective 3.3.1 Transformation stresses 3.3.2 Establishing a load transfer path to determine the ‘weakest link’ 3.3.3 Case study: The weakest link principle 3.3.4 Case study: Failure of a backhoe dipper arm 3.4 Computer-aided technologies 3.4.1 Case study: failure of an open-ended spanner 3.5 The forensic engineering Report 3.6 Concluding remarks 3.7 References Chapter 4 Analytical methods 4.0 Introduction to a typical forensic engineering ‘toolbox’ 4.1 Non-destructive testing (NDT) 4.1.1 Case study: Failure of a power transmission shaft 4.2 Crack detection and the human eye 4.2.2 Surface appearance of common cracks 4.2.3 Other crack detection techniques 4.3 Hardness testing 4.3.1 Case study: Pin-punch splintering 4.3.2 Relationship between hardness and tensile strength 4.4 Indirect stress/strain analysis 4.4.1 Brittle lacquer technique 4.4.2 Case study: Cycle accident 4.4.3 Photo-elastic stress measurement 4.5 Conventional (contact) radiography 4.5.1 Case study: Failure of a vehicle motherboard 4.5.2 Case study: Heavy goods vehicle fire 4.6 Summary of NDT inspection 4.7 Forensic optical microscopy 4.7.1 Macroscopic examination 4.7.2 Examination under magnification: optical microscopy 4.7.3 Reflected light microscopy 4.7.4 Stereo microscopy 4.8 Metallography 4.9 Scanning electron microscopy 4.9.1 The environmental scanning electron microscope (ESEM) 4.9.2 Case study: Hit and run accident 4.10 Optical versus scanning microscopy 4.10.1 Case study: Printed circuit board (PCB) failure 4.10.2 Case study: Prototype PCB failure 4.11 Energy dispersive X-Ray analysis (EDAX) 4.12 Destructive testing methods 4.12.1 Tensile testing 4.12.2 Flexure or bending 4.12.3 Case study: Cracking of aluminium pressings 4.12.4 Torsion testing 4.12.5 Shear testing 4.12.6 Izod or Charpy impact test 4.12.7 Differential scanning calorimetry (DSC) 4.12.8 Case study: Electronic component registration difficulties 4.13 Novel tools and techniques 4.13.1 The contour method 4.13.2 Neutron diffraction 4.13.3 Nano test systems 4.13.4 Flash thermography 4.13.5 Thermographic Signal Reconstruction (TSR) 4.13.6 Electromagnetically induced acoustic emission (EMIAE) 4.13.7 Pulsed eddy current (PEC) 4.13.8 Microwave technology 4.14 References Chapter 5 Sources of stress and service failure mechanisms 5.0 Introduction 5.1 Fundamental mechanical background 5.1.1 Stresses and strains 5.1.2 Ductile and brittle transition 5.1.3 Fracture toughness and linear elastic fracture mechanics (LEFM) 5.1.4 Limitations of a fracture mechanics approach 5.1.5 Stress Concentration (Kt) 5.1.6 Case study: stress concentration – cement mill power input shaft 5.1.7 Residual stresses 5.1.8 Summary of fundamental mechanical background 5.2 Service failure mechanism 5.2.1 Case study: Hubble space telescope mirror and the Team Philips catamaran 5.3 Mechanical Failure 5.4 Hydrogen Embrittlement 5.4.1 Sources of hydrogen 5.4.2 Hydrogen induced brittle failure 5.5 Impact 5.6 Bending 5.7 Torsion 5.8 Creep 5.9 Fatigue 5.9.1 Minimizing susceptibility to onset of fatigue failure 5.9.2 Case study: Failure of a power transmission gear wheel 5.9.3 Fatigue related failure modes 5.9.4 Approximating the history of a fatigue failure 5.9.5 Summation of fatigue as a service failure mechanism 5.10 Wear 5.11 Corrosion 5.11.1 Case study: The Statue of Liberty 5.11.2 Stress Corrosion Cracking (SCC) 5.11.3 Case study: SCC of brass impeller blades 5.12 Manufacturing fabrication as a source of stress 5.12.1 Casting 5.12.2 Casting Failure Analysis 5.12.3 Case study: Extrusion press 5.12.4 Welding 5.12.5 Quench cracking 5.12.6 Tempering and toughening 5.13 References Chapter 6 Fracture morphology and topography 6.0 Introduction 6.1 What is meant by the term ‘failure’? 6.2 Fracture and fracture path morphology 6.3 Ductile or brittle failure 6.4 Brittle overload (fast) fracture features 6.5 Ductile-brittle transition 6.6 Fracture surface features 6.7 Fatigue fracture 6.7.1 Low and high Cycle Fatigue 6.7.2 Chevron and striation combination 6.7.3 Case study: Internal combustion engine crank-shaft failure 6.7.4 Splined shafting 6.7.5 Ratchet marks 6.7.6 Thermal Fatigue 6.8 Additional modes of progressive failure 6.8.1 Corrosion 6.8.2 Stress Corrosion Cracking (SCC) 6.8.3 Crevice corrosion 6.8.4 Environmentally assisted cracking (EAC) 6.8.5 Wear 6.8.6 Wear of rolling contact elements 6.8.7 Case study: an agricultural bearing failure 6.9 Summary 6.10 References Chapter 7 The engineer in the courtroom Introduction 7.1 The role of the ‘expert’ 7.2 The expert report 7.3 Pre-trial meeting of experts 7.4 Alternative dispute resolution (ADR) 7.5 The single joint expert (SJE) 7.6 The role of Case Law 7.7 The engineer in the Court room 7.8 In summary 7.9 References Chapter 8 The Art of case study analysis as a teaching tool Introduction 8.1 Historic use of case study analysis 8.2 Air accidents, mortality statistics and failure case studies 8.3 What constitutes a ‘case study’? 8.3.1 Case study: North-sea ferry engine bolts 8.3.2 Case study: Hot-spot boiling erosion 8.4 Writing a relevant case study 8.4.1 Case study: Crankpin axle from a bicycle 8.5 Examples of case study themes. 8.5.1 Case study: Collapse of terminal 2E Charles de Gaulle International Airport. 8.5.2 Marine disaster case study examples 8.5.3 Case study: loss of the first British off-shore oil drilling platform 8.5.4 Case study: loss of the Alexander Kielland semi-submersible oil drilling platform 8.5.5 Colliery disaster case study examples Engineering in medicine 8.6.1 Case study: the DePuy Ultamet Metal-on-Metal (MOM) Articulation hip replacement Concluding remarks References Chapter 9 Failure due to manufacturing faults - case studies 9.0 Introduction 9.1 Traumatic failure 9.2 Femoral stem failure of a total hip prosthesis 9.3 Failure of Freight Containers 9.4 Splintering Failure of a Pin punch 9.5 Failure of a vehicle fuel delivery rail 9.6 Failure of a Presentation Cake Knife 9.7 Failure of an Aerobic Mini-Stepper 9.8 Failure of oil pump gearing 9.9 Replacement Gears for HGV (heavy truck) Gearbox 9.10 Vehicle engine radiator cooling fan Chapter 10 Automotive component failure: road traffic incidents and accidents – case studies 10.0 Introduction 10.1 Motor Vehicle Accidents as a Result of Steering Shaft Failure 10.1.1 Fatal Crash of a Small Family Saloon Car 10.1.2 Heavy Goods Vehicle (HGV) Accident 10.1.3 Steering Shaft Failure on a Vintage Car 10.1.4 The ‘Boy Racer’ 10.2 Wheel Detachments 10.2.1 Wheel Nut Loosening and Stud Fatigue 10.2.2 Wheel Dish Cracking 10.2.3 Stub Axle Failure 10.3 Brake Pipe Failures 10.3.1 Brake Failure by Fatigue 10.3.2 Failure of a Polymeric Air-Brake Hose 10.4 Gearbox Synchronizer Ring failure 10.5 Fatal Tow Hitch accident Chapter 11 Fraudulent insurance claims - Case studies 11.0 Introduction 11.1 Perforated central heating radiator 11.2 Perforated Oil Filter 11.3 Major Engine Damage, Allegedly Due to Loss of Oil 11.3.1 A probable motive for inflicting the damage observed 11.4 Engine hairline cracking as a result of an alleged impact 11.5 Agricultural tractor engine damage 11.6 Con-Rod failure 11.7 Piston Failure on a Racing Car Chapter 12 Criminal Case studies 12.0 Introduction 12.1 Counterfeit Coins 12.1.1 The Use of Currency as a Feedstock Material for counterfeiting 12.1.2 The Base Metal One Pound Coin 12.1.3 The ‘Struck’ One Pound Coin 12.1.4 Footnote to Counterfeiting 12.2 Staged or Fraudulent Road Traffic Accidents Within the UK 12.2.1 Deliberate ‘damage’ 12.2.2 Car hire insurance fraud 12.2.3 Staged ‘accidents’ 11.3 Shotgun Pellets 12.4 Metal Theft 12.4.1 An Additional Metal Theft Case 12.5 Chain from Murder 12.6 Coin Box Busters 12.7 Re-melting Beer Barrels