2014-09-08 Utveckling av kvalitets- och övervakningstekniker för svetsade produkter Eric Lindgren M.Sc. IWE, [email protected] What is Quality? Dynamic Properties Cosmetic Appearance Joint Quality Static Properties Corrosion Resistance 1 2014-09-08 QUALITY SYSTEM SYSTEM DEFECT METHOD Gauges Laser Profile Sensor PT External Imperfections MT ET Welding Destructive Testing X-ray Internal Imperfections Ultrasonic Laser Ultrasonic Destructive Testing 2D/3D Laser Profile Sensor 2 2014-09-08 System Principle Overall sequence of algorithm: - Process weld bead surface data obtained by 3D scanning from valid standards. - The output is geometrical variance along the weld bead. - Imperfections to be measured; outer transition radius, throat thickness, leg length, leg deviation, undercuts, etc. Laser Ultrasonic Benefits with Laser Ultrasonic: No sensor in contact with work piece All frequencies and wave types are generated at the same time Rapid measurements Inspection of high temperature work piece Inspection of fast moving work piece Viable on flat, curved and recessed surfaces Insensitive to surface condition 3 2014-09-08 Laser ultrasonic principles Generation pulsed YAG laser 100mJ/pulse Pulse length 8ns 1064nm (IR) Detection continuous YAG laser 532nm (green) Example of setup geometries 4 2014-09-08 Measurable quantities Interface reflections Attenuation Sound velocity (Refractive index changes) (Scattering, Absorption) (Elasticity) - Defect detection - Grain size - Phase constituents - Precipitation - Defect detection - E-modulus - Poisson’s ratio - Mechanical strength - Texture - Internal stresses - Phase transformation - Recrystallization - Thickness of layers Material characterization Defect detection Dimension measurements A and B scans for good and bad weld No Defects Defects 5 2014-09-08 Industrial trials High quality and robust signals despite difficult environment including vibrations, dust, steam Parallel ongoing research projects Internal imperfections External imperfections Geometrical aspects Adhesive characteristics 12 6 2014-09-08 Internal imperfections Internal crack Internal lack of fusion Lack of penetration Internal porosities 20 mm 40 mm 47 mm 52 mm 65 mm E. Lindgren, P. Lundin and K. Fahlström, Advanced quality assurance of welded and adhesively bonded joints, Report KIMAB-2014-102, 2014. External imperfections Undercut Incorrect weld toe Overlap and cold lap Unequal leg length 7 2014-09-08 Geometrical aspects To ensure fatigue performance of welded structures focus on clearly defined weld penetration and outer transition geometry. Will be included in SS-EN ISO 5817 during 2014, with extended requirements will be added for the weld toe. Adhesive characteristics Insufficient curing Pores 30 min Joint: Overlap Material: DP800 Plate Thickness: 2mm 15 min Lack of adhesion E. Lindgren, P. Lundin and K. Fahlström, Advanced quality assurance of welded and adhesively bonded joints, Report KIMAB-2014-102, 2014. 8 2014-09-08 Vision for quality assurance of welded structures ONWELD - new ON-line method for quality assurance of WELDed structures QUALITY – Advanced quality assurance of welded and adhesively bonded joints On-line measuring Process Future: Selected weld quality is used as input. Full scan along the welded / brazed joint. r, u, a, etc. Improved and early QA & control is needed Today: Received weld quality is attempted to be measured on the final product. Few selected positions only. Weld quality in practice Example: Welded I-beam, requirements set as VC in Volvo STD 181-0004 VC VD VC Need to be corrected 9 2014-09-08 Partners 10
© Copyright 2024 ExpyDoc
