Razvoj in analiza varjenja MAG debelejšega nerjavečega jekla

Aoun, Ali (author), Klobčar, Damjan (mentor), Trdan, Uroš (comentor)

V zaključni nalogi smo analizirali potek varjenja MAG 60 mm debele pločevine iz nerjavečega jekla z oznako 1.4404 v sočelnem zvarnem spoju X s plinsko mešanico s 97,5 % argona in 2,5 % ogljikovega dioksida. Za odobritev postopka varjenja je bilo treba na varjencu izvesti kontrolo zvarnih spojev. V teoretičnem delu so bile najprej predstavljene značilnosti nerjavečih jekel, osnovni pojmi varjenja, značilne napake ter preiskave oziroma kontrola zvarnih spojev. Pri varjenju je bil najprej izdelan korenski varek s pomočjo keramične podložke, ki so mu sledili polnilni varki. Skupno je bilo narejenih 33 varkov. Glavni izziv je bil ohranjati medvarkovno temperaturo med varjenjem pod 110 °C. V primeru preseganja te temperature je bilo treba varjenec ohladiti. Po varjenju smo izvedli neporušitvene in porušitvene preiskave. Kakovost zvarnega spoja smo neporušno preverili s penetrantskim preizkusom in radiografsko kontrolo. Na zvarnih spojih smo izvedli test natezne trdnosti, upogibne trdnosti, Charpyjev preizkus udarne žilavosti in metalografsko preiskavo. Ugotovili smo, da izbrani in razviti postopek varjenja zagotavlja izdelavo kakovostnih zvarnih spojev na debelih pločevinah. S tem smo tudi potrdili odobritev uporabljenega varilnega postopka.

• Language: Slovenian
• Keywords: varjenje MAG, nerjaveče jeklo, napake v zvarnih spojih, porušitvene preiskave, neporušitvene preiskave, odobritev varilnega postopka
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [A. Aoun]
• Year: 2024
• Number of pages: XX, 60 str.
• PID: 20.500.12556/RUL-154857
• UDC: 621.791.75:669.14:620.17(043.2)
• COBISS.SI-ID: 188326403
• Publication date in RUL: 06.03.2024

AOUN, Ali, 2024, Razvoj in analiza varjenja MAG debelejšega nerjavečega jekla [online]. Bachelor’s thesis. Ljubljana : A. Aoun. [Accessed 25 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=154857

Secondary language

• Language: English
• Title: Development and analysis of MAG welding of thicker stainless steel

Abstract

In the final assignment, we analysed the MAG welding process of 60 mm thick stainless-steel sheet 1.4404 in the X-butt weld with a gas mixture of 97.5% argon and 2.5% carbon dioxide. To approve the welding process, it was necessary to carry out an inspection of the welded joints on the weld. In the theoretical part, the characteristics of stainless steels, basic concepts of welding, typical defects and investigation or control of welded joints were first presented. During welding, the root wool was first produced with the help of a ceramic ferrule, followed by the filling welds. A total of 33 welds were made. The main challenge was to keep the weld temperature between passes below 110 °C during welding. If this temperature was exceeded, the weld had to be cooled. After welding, we conducted non-destructive and destructive testing. The quality of the welded joint was verified by penetrating test and radiographic control. Tensile strength test, bending test, Charpy impact test and metallographic examination were performed on welded joints. We found that the selected and developed welding process ensures the production of high-quality welded joints on thick sheets. This also confirms the approval of the welding procedure used.

• Keywords: MAG welding, stainless steel, weld defects, destructive testing, non-destructive testing, approval of welding procedure