Thermal NDT CONSULTING Michael Kröning NEW TE TECHNIQUES ES IN TH THERMAL L NONDESTRUCTI CTIVE VE TESTING Introduction: Basics of Infrared Technical diagnostics Active NDT of materials Prof. Vladimir Vavilov Tomsk Polytechnic University, Russia vavilov@tpu.ru CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Michael Kröning CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING № 6 Infrared ed Thermog mography phy CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING What makes IR thermography so useful? There are, at least, five things which make IR thermography so uniquely useful. • It is non-contact – uses remote sensing • It is two-dimensional – produces images • It is accomplished in real time • It senses heat losses which irreversibly accompany human activity • It is applicable to both metals and non-metals CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Image analysis Radiation science Camera handling Thermal science Inspection routines and reporting Applications CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Computer What is an Infrared System? Atmosphere Infrared imager Test target Nondestructive Testing (NDT) of Materials (thermal Processing software stimulation is required) Night Vision Technical Diagnostics Search & Rescue Predictive Maintenance Surveillance Condition Monitoring Alarm systems CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING V.Vavilov 3-5 m m (Middle Wave) and 7-13 m m (Long Wave) wavelength bands are typically used in IR thermography CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Opto-mechanical High-precision scanning mechanics Detector array A typical array consists of tens thousand of sensitive elements Two Types of IR Imagers CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Infrared Image 10 $/m 2 +4 0 С 8 $/m 2 +2 0 С 6 $/m 2 0 0 С 0 -2 0 С • Dark areas- cold, bright areas - hot • What does this IR image tell about? Standard IR images reflect distribution of “radiation” (“apparent”, “effective”) temperature across a building facade. Special data processing may provide versatile information on issues of interest. CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Night Vision (Police Operations) CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING IR Thermography Exotics: Counting Deer in an Open Field at Night (at 400 m distance) CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Applications: Technical Diagnostics in Industry In Russia, IR Thermographic diagnostics of tanks with liquid ammonia is obligatory by law. At Tomsk Polytechnic University, the federal guidelines on the evaluation of industrial chimneys have been developed. CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Technical Diagnostics in Industry Defective rod insulator: D T=10 o C Defective rod insulator: D T= 4 o C Porcelain and Polymer Insulators CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING A typical defect in bolt joints is the absence of washers when connecting copper wires with a flat outlet made of copper or aluminum. It is recommended to perform the IR thermographic inspection of bolt joints once a year because defects appear continuously depending on load, impact of chemical reagents, grade of tightening, etc. Contact Joints (Bolt, Welded, Compressed) CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Steam Line Surveys CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Inspection of Trains with Radioactive Wastes (Germany, 2010) CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING CITEC Su Zhou May 29 th , 2012
Thermal NDT CONSULTING Active Thermal NDT of Materials (Pulsed & Thermal Wave, or Lockin Techniques): Optical Heating CITEC Su Zhou May 29 th , 2012
Basic Inspection Procedure Step 1: Software Test modeling & optimization, or Having the NDT standard, or Having the experience with the object to be tested Step 2: Choosing hardware Cylindrical and conical Key element of the objects made of composite strategy is a specialized Software customers: Boeing, NASA materials software ThermoCalc-6L, Step 3: ThermoFit Pro Performing the test and recording data Step 4: Processing data and documenting results 4.1 Characterizing defects Detecting defects Software 4.2 Producing the map of defects
Thermal NDT CONSULTING Heating Procedures I – Optical Heating II – Inductive Heating III – Electric Current IV – Microwave Heating Heating Inductive heat source Moisture AC Crack Metal Microwave Non-metal heat source Area IR heater imager AC/DC Metal V – Heating with Gas VI – Air Flux Heating VII – Sonic IR Imaging VIII – Natural Heating (Liquid) (Thermosonics, Ultrasonic Lockin Thermography, Vibrothermography) Gas, Sun liquid Ultrasonic emitter Mine Turbine blade CITEC Su Zhou May 29 th , 2012
Advanced Data Treatment in Thermal NDT Processing Processing Image Sequence Single Image General Temporal Analysis Using Heat Conduction Models Normalization Filtration (smoothing, sharpening, Fourier Analysis (Pulse (subtraction, division, morphological treatment etc.) Phase Thermography) 3D filtration) Fitting Histogram Analysis Non-Linear Fitting (polynomial, & Modification exponential etc.) (stretching, Optimum observation binarization etc.) Neural Networks Early Detection Wavelet Analysis Choosing Palette Thermal Tomography Principal Component Derivative Analysis Data Fusion Analysis Defect Characterization
Solving Inverse Problems and Defect Characterization in Thermal NDT T h d Typical accuracy: l few percent by h , l , There are three defect parameters to be typically evaluated by surface temperature distributions: tens percent by d • Defect lateral size h (visual analysis or the Full Width Half Maximum (FWHM) technique • Defect depth l (by an inversion technique) • Defect thickness d , or thermal resistance R d (by an inversion technique) Source image (CFRP) Depthgram Thicknessgram 2.56 mm 0.0039 m 2 KW -1 1.36 mm 5 mm 0
Thermal NDT CONSULTING CITEC Su Zhou May 29 th , 2012
Applications: Detection of Hidden Corrosion in Metals Aircraft aluminum panel (2 mm), front and rear surface Corrosion 75% 7% A developed algorithm allows both corrosion detection and quantitative evaluation of material loss 77% 77% 54% 54% 20% material loss – detection Steel thickness >10 mm limit
Ultrasonic IR Thermography (Sonic IR Imaging, Thermosonics, VibroIR) CONSULTING D T T nd D T T amb T amb УЗВ излучатель Ultrasonic stimulation (22 kHz, 300 W) Impact damage in graphite epoxy composite CITEC Su Zhou May 29 th , 2012
Ultrasonic IR Thermography CONSULTING Optical Ultrasonic stimulation Crack in stimulation composite 22 kHz 0.2-1 kW Delamination in Ultrasonic stimulation Optical graphite/epoxy stimulation CITEC Su Zhou May 29 th , 2012
Ultrasonic IR Thermography CONSULTING Crack in Turbine Blade CITEC Su Zhou May 29 th , 2012
CONSULTING Inspecting 4 mm-thick graphite epoxy composite Defect that are located close to the inner surface cannot be detected in a one-sided test IR camera Halogen tubular Defect map (cylinder lamp evolution, 6 images) In some cases, one-sided test can be substituted with a more sensitive two-sided test CITEC Su Zhou May 29 th , 2012
Ultrasonic IR Thermography CONSULTING Defects in aluminum car cylinder block CITEC Su Zhou May 29 th , 2012
Eddy Current IR Thermography CONSULTING for electrically conductive materials (compressor blades, toothed gear wheels etc.). Eddy currents are excited by inductors with power up to few kW. The carrier frequency of few hundred kHz is modulated with a frequency of 0.01-1 Hz. Penetration depth of 100 kHz eddy currents in: IR camera • steel - 0.07 mm Inductor • aluminum honeycombs – 5 mm • graphite/epoxy composite - 50 mm Generator Sample Courtesy: Starmans Electronics, Czech Republic CITEC Su Zhou May 29 th , 2012 Steel Bar Inspection in Automotive Industry
Eddy Current IR Thermography CONSULTING Steel Casting Samples CITEC Su Zhou May 29 th , 2012
Eddy Current IR Thermography CONSULTING (Tomsk, 2012) Section of a railway road car truck with a fatigue crack After image Original image processing CITEC Su Zhou May 29 th , 2012
Eddy Current IR Thermography CONSULTING (Tomsk, 2012) CITEC Su Zhou May 29 th , 2012
Recommend
More recommend
