Component Assessment and Reliability

- Tasks / Main focus
- Special facilities
- Contact person

Department 55 Component Assessment and Reliability is subdivided into the following Units:

  • Unit 551  Structural Durability
  • Unit 552  Integrity Assessment
  • Unit 553  Reliability and Probabilistic Assessment

The department mainly deals with the reliability and lifetime assessment, including safety and risk analysis for components, structures and systems of mechanical engineering, plant construction and power plant engineering.

In this context, application-oriented research forms the basis for the available calculation methods and models with which the various stages of the lifecycle of a component, a structure or a system can be evaluated reliably. This also enables us to analyze very complex loading conditions and to draw conclusions regarding the structural durability and integrity of components.

Calculations and proofs on the basis of current rules and standards, as for example the harmonised European standards (EN 13445: Unfired pressure vessels, EN 13480: Metallic industrial piping, etc.), the ASME Boiler and Pressure Vessel Code, the British standard or the rules of the Nuclear Committee (KTA) is an essential part of the industrial services of the department. The necessary computing software is also available for this purpose. This work is also carried out as consultant and technical supervisor on behalf of regulatory bodies.

The department also deals with probabilistic analyses and risk assessments. In addition, the department develops its own software, database system for condition-based analyses and monitoring of components and machine groups in power plants.

The department is equipped with the latest numerical and analytical tools. Finite element software, such as ABAQUS, ANSYS, ADINA and software for mesh generation and analysis with interfaces to all common CAD-systems are used. The available computers vary from the supercomputers at the High performance Computing Centre Stuttgart to own powerful local workstations and servers.

Schadensuntersuchung an einer Kurbelwelle
Fatigue assessment of thermo-mechanical loaded piping components including dissimilar welds

 

Tasks / Main focus
Research
  • Investigations on the fatigue behavior under High Cycle (HCF) and Very High Cycle (VHCF) Fatigue loading of austenitic and ferritic materials and welded joints in air environment and under high temperature water conditions
  • Investigations on the corrosion fatigue behavior of dissimilar welds under high temperature water conditions
  • Microstructural investigations of materials and components in case of corrosion fatigue
  • Experimental and numerical investigations of the damage mechanisms of metallic piping with turbulent flow in under high pressure and high temperatures loadings
  • Analysis of the load bearing and failure behavior of components in power plants
  • Quantification of the load-bearing capacity of mechanical components in case of multiple accident loadings using a damage-mechanically based limit strain concept
  • Application of statistical and probabilistic methods
  • Reliability assessment of components with welded joints under consideration of  ultrasonic test results of real flaw configurations
  • Development of micro-mechanically based models for the integrity assessment, e. g. thick-walled forgings containing crack fields
  • Interactions of the coupled system “building – post installed anchor – piping” during earthquake loading
Versuchsaufbau Bauwerkbefestigung

Development
  • Development of concepts for the integrity assessment and ageing management
  • Software development in the fields of numerical simulation, fracture mechanics and crack growth, condition analysis and monitoring, analyses acc. to standards and guidelines
  • IT- systems for the condition based monitoring of power plants
Schaufel FE-Analyse
Calculation of the fatigue usage of a motor generator in a pumped-storage power plant
Coupled fluid dynamic simulation (CFD) of thermal fluctuations and stratification at a T-joint during cold injection
Testing / Determining
 
  • Application of technical standards and guidelines (DIN, EN, TRD, AD, KTA, ASME, …) for the design and assessment of structures, systems and components
  • Experimental and numerical analysis of the vibration behavior (e. g. modal analysis) of mechanical or civil engineering structures, e.g. piping systems in chemical plants or in power plants
Investigations / Analyses / Expertises
  • Durability assessment using numerical and analytical methods (fatigue analysis and fracture mechanics analysis to determine the remaining life time and load bearing capacity of mechanical components and systems)
  • Safety analysis, leak-before-break analysis and proof of integrity for components and systems
  • Analysis of the structural durability of components and systems in hydroelectric power  plants
  • System identification and optimization by means of vibration analysis
  • Analysis of operational data with subsequent lifetime calculation including localisation of components with hot spots regarding the consumption of lifetime. This includes the analysis of operational data from structural health monitoring, calculation of lifetime consumption from these operational data as well as data analyses for risk based lifetime management
  • Consulting and preparation of certificates for ministries, regulatory bodies and industry
Versuchskreislauf
Fluid-structure-interaction (FSI) test circuit at MPA University Stuttgart
Surveillance / Certification
  • Condition based monitoring of mechanical or civil engineering structures (towers, bridges) and their interfaces (e.g. anchors)
Consulting Service
  • Consulting on safety related issues
  • Measurement and evaluation of vibrations
  • Seismic hazard analyses
  • Optimisation of lifetime and maintenance measures
  • Implementation of condition based maintenance strategies
  • Preparation of risk analyses
  • Support of small and medium-sized enterprises using scientific methods
  • Consulting activities in the area of probabilistic procedures and approaches
  • Consultation and support of customers in dealing with large amounts of data in the context of reliability analyses (for example, exhaustion calculations according to TRD 508/301)
  • Support, consultation and training regarding the developed application software
Cooperation in Committees
  • Participation in committees on the development and review of technical codes and standards (CEN, DIN, KTA) and in committees of expert associations (DECHEMA, DVM, DVS, DIN/ISO, ESIS, FDBR, VDI, VGB) as well as in DFG-research groups
  • Participation in international research networks (NUGENIA) and organizations (OECD/NEA, IAEA)
Beschleunigungsaufnehmer Diagramm
Condition based maintenance of vibrational loaded systems
Software package Xpipe ™ R6/p
Courses
  • Supervision of student work (Bachelor and Master courses) in close cooperation with the IMWF
  • Software development within the framework of student research projects (Bachelor, Master)
Information
  • Publications, lectures, workshops
  • Publications at international conferences and meetings: ASME Pressure Vessels and Piping (PVP) Conference, Structural Mechanics in Reactor Technology (SMiRT))
Special facilities
  • Modular test circuit for experimental investigations on flow-through pipelines (fluid-structure-interaction (FSI) test circuit)
  • Software package Xpipe ™ for evaluation of cracked components according to different aspects (R6 method, crack growth, boundary loads, leakage surfaces)
  • Numerical and experimental modal analysis, model-updating programs
  • Vibration analysis software
  • Simulation and CAD programs
  • Access to supercomputers of the High Performance Computing Centre Stuttgart (HLRS) and the bwUniCluster of the KIT in Karlsruhe
Further Information
Contact person

Secretary

Mrs. A. Ulm-Sawade



++49 (0)711/685-63054

Head of Department

Mr. Dr.-Ing. L. Stumpfrock
(stv. Head of Dep.)

 

++49 (0)711/685-63041
++49 (0)711/685-63053

Units

Structural Durability

 

Mr. Dipl.-Ing. F. Dwenger

Mr. Dipl.-Ing. F. Silber

 

++49 (0)711/685-67676

++49 (0)711/685-60163

Integrity Assessment

Mr. Dr.-Ing. L. Stumpfrock

Mr.Dr.-Ing. K. Kerkhof

++49 (0)711/685-63041

++49 (0)711/685-63064

Reliability and Probabilistic
Assessment

Mr. Dr. rer. nat. G. Wackenhut

Mr. Dr. rer. nat. R. Lammert

++49 (0)711/685-63044

++49 (0)711/685-60424