Stremeckas Š. Strains and deformations state research of louded welded joint with circular soft seam: Master thesis of mechanical engineer / research advisor associate prof. habil. dr. A.Bražėnas, Šiauliai university, department of technologic, department of mechanical engineering. – Šiauliai, 2006. – 30 p. Welded joints has an important part in production of ships, machines, buildings and other important industrial parts. These joints are mostly in the concentration zones of important constructions from which belongs their strenght and durabily because during the work the proportional limits of materiais are exceeded and there static or cyclic elasto-plastic strain appears. Therefore investigations of these welded joints are very important. In the first chapter there is a review about mechanically heterogeneous welded joints. It describes parameters of simetric welded joint with simple soft seam. The second chapter presents analysis of separate welded joint parameters. Obtained analysis allows appraise condition of mild and hard materials and properly evaluate state of welded joint from which belongs construction strenght and durability.

Baigiamajame magistro darbe nagrinėjama termitiniu būdu skirtingais parametrais suvirintų bėgių jungčių kokybė. Analizuojama termitinio suvirinimo mišinio kiekio bei pakaitinimo laiko įtaka suvirintų jungčių kokybei. Tam, kad būtų nustatytos suvirintų jungčių mechaninės savybės, buvo atlikti šie bandymai: viršutinės bėgio dalies kiečio bandymas, lėtojo lenkimo bandymas, termiškai suminkštintos zonos kiečio pasiskirstymo matavimas, ilgalaikiai bandymai. Tyrimais nustatyta kokią įtaką, turi suvirinus bėgių jungtis be pakaitinimo, esant skirtingiems pakaitinimo laikams ir skirtingam termito kiekiui. Remiantis gautais rezultatais pateiktos išvados. / In the final masters degree thesis examines the quality of using different parameters Aluminothermicaly welded rail joints. Influence of the quantity of Aluminothermic welding mixture for quality of welded joints, and heating time is analyzing. In order to determine the mechanical properties of welded joints following tests had been made: hardness test of upper part of the rail, long term bending test, hardness test of the distribution of heat-softened area, other long-term tests. Results of research have determined the influence of different heating time and different quanity of thermites content for welded joints without using heating. Based on this results the final conclusion was presented .

Darbe tiriami mažaanglio plieno S235J2 (LST EN 10025:2004) suvirintų siūlių pasikeitimai, plieną apvirinant skirtingais glaistytaisiais elektrodais ir suvirinimo režimais. Tyrimų metu buvo naudojami AV-23 ir AV-66 glaistytieji elektrodai bei keičiamas trumpojo jungimo srovės stipris. Nustatytas ryšys tarp metalo įvirinimo gylio, rumbelės aukščio, išlydytų lašų dydžio, išlydytų lašų kiekio, trumpojo jungimo trukmės ir trumpojo jungimo srovės dydžio. Gauti tyrimų rezultatai, nubraižyti priklausomybių grafikai ir pateiktos išvados. Darbą sudaro: įvadas, literatūros apžvalga, eksperimentuose naudojama įranga ir medžiagos, tyrimo metodika, tyrimų metu gauti rezultatai, grafikai, išvados, literatūra. Darbo apimtis: 83 p. teksto, 73 iliustr., 18 lent., 23 bibliografiniai šaltiniai. / In final work was analyzed the changes of seams properties of steel S235J2 (LST EN 10025:2004), produced by welding with different technology are discussed. Samples were welded by hand arc welding, using AV-23 and AV-66 welding electrodes. The welded seams were made by changing short-circuit current. The duration of weld depth, ridge height, metal drop size, metal drop frequency, short-circuit time and short-circuit current value are determinated. The results of the research are given in graphs, final conclusions are also written. Structure: the introduction, survey of the related literature, equipment and materials, description of the methodology, results of research, graphs of the results, conclutions, references. Thesis consist of: 83 p. text, 73 pictures, 18 tables, 23 bibliographical entries.