Contents of the Paton Welding Journal
no.7, 2008 |
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| SCIENTIFIC AND TECHNICAL |
Makhnenko V.I., Velikoivanenko E.A. and Olejnik O.I. Characteristics of fracture resistance of pipeline material within the zone of defects, risk of failure | 2 |
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Considered are characteristics of pipeline steels and their welded joints, determining fracture resistance in the zone of detected defects. Attention is focused on corrosion thinning defects, as well as development of corrosion cracks. Proceeding from analysis of the publications and authors' investigations, recommendations are given on quantitative values of the above characteristics under static loading on main pipeline. |
Turichin G., Valdaitseva E., Pozdeeva E., Dilthey U. and Gumeniuk A. Theoretical investigation of dynamic behavior of molten pool in laser and hybrid welding with deep penetration | 11 |
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The article devoted to the simulation of dynamic phenomena of the laser welding process with deep penetration. The presented model is a future development of steady-state model of laser welding. It based on the approach of Lagrange mechanics and takes into account melt flow, wave motion on the cavity surface, melting viscosity, bubble pressure, recoil pressure and radiation parameters. The results of calculations describe self-oscillation nature of the cavity shape during welding. With the base of presented model a simulation of keyhole collapse, leading to defect formation, and a description of acoustic emission spectra from the cavity has been developed. |
Kondratiev I.A., Ryabtsev I.A., Bogajchuk I.L. and Novikova D.P. Structure of deposited metal of the type of graphitised hypereutectoid steels | 15 |
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Studied was structure of the deposited metal of the type of graphitised hypereutectoid steels and influence on the graphitisation process by different cladding techniques. It was established that tempering at 400 °C with holding for 2h and delayed cooling with the furnace should be applied immediately after cladding for graphitisation of the deposited metal containing not less than 1.5 wt.% C and 1.1 wt.% S. Modification of the deposited metal by aluminium and calcium allows activation of the graphitisation process. |
Sokolsky V.E., Roik A.S., Kazimirov V.P., Ryabtsev I.I., Mishchenko D.D., Ryabtsev I.A., Kotelchuk A.S. and Tokarev V.S. Effect of zirconia on properties of slag in flux-cored wire submerged-arc surfacing using flux AN-348A | 19 |
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Effect of zirconia on slag properties in submerged-arc surfacing using low-alloy flux-cored wire PP-Np-20KhGS and flux AN-348A was investigated. It is established that, when depositing the first layers, zirconia is contained in the surface layer of the slag crust adjacent to the deposited metal in the form of individual inclusions of predominantly monoclinic shape. Formation of zirconia induces substantial microstresses in the slag crust and leads to its cracking, thus preventing chemical bonding of the crust and deposited metal through an interlayer of oxides and improving detachability of the slag crust. |
| INDUSTRIAL |
Gedrovich A.I., Tkachenko A.N., Tkachenko S.N. and Elagin V.P. Nature of fracture of welded joints of 10Kh13G18D + 09G2S steels at vibration loads | 24 |
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Peculiarities of fracture of welded joints between austenitic steel 10Kh13G18D and pearlitic steel 09G2S under vibration loads were investigated. The investigation results allowed identification of the mechanism of impact by technological factors in welding on service crack resistance of the above joints. |
Tsaryuk A.K., Skulsky V.Yu., Moravetsky S.I. and Sokirko V.A. Change of mechanical properties of welded joints of carbon and low-alloyed steels at electromagnetic impact | 27 |
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The paper deals with published results of investigations of the impact of high density electric current pulses on impact toughness of St3 steel. It is noted that the electromagnetic impact mechanism suggested by the authors can only be manifested in a narrow layer near the metal sample surface. Results of experimental investigations are given, which demonstrate that passing electric current of a comparatively low density through the metal of steel welded joints also leads to a marked change of its impact toughness. |
Bernadsky V.N. French Institute of Welding today | 31 |
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The paper gives information about the modern structure and forms of scientific-technical activity of the French Institute of Welding. The main research areas and forms of their realization in industry are highlighted. The role of informational support of all structures of the «French Institute of Welding» group is shown. |
| FROM HISTORY OF WELDING |
Litvinov A.P. Development and progress of arc welding in active gases | 36 |
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Analyzed is the history of emergence and development of arc welding in active gases. It is noted that this welding method was developed on the basis of progress in metallurgical and electrodynamic components of the process. Maximum effect of its application was achieved at pulsed control of electrode melting, as well as by using special compositions of electrode wires and shielding gas. |
| BRIEF INFORMATION |
Yushchenko K.A., Savchenko V.S., Chervyakova L.V., Izbash V.I. and Solyanik V.G. Analysis of the causes of fracture of blades in axial-flow compressor of unit GTK-25I | 41 |
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The causes of fracture of martensitic-ferritic steel blades in inlet rotary distributor of axial-flow compressor of the gas-pumping unit were studied. Fracture of the blades occurs in several stages: formation of corrosion sites, initiation and propagation of cracks within the zone of corrosion damage under cyclic loading, and fracture. At the initial stage, corrosion damage takes place at the martensiteÄferrite interface, after which it develops from intergranular into intragranular corrosion fracture along the martensite needles, and then into fatigue fracture through the bulk of grain. |
Developed at PWI
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