Usporedna analiza zavarenih spojeva izrađenih konvencionalnim MAG i D-Arc postupkom

master's thesis

• Title (english): Comparative analysis of welded joints produced by conventional MAG and D-Arc process
• Author: Mario Golubić
• Mentor: Ivica Garašić (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2018-07-12, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

U ovome radu obrađena je usporedna analiza zavarenih spojeva izrađenih konvenionalnim MAG i novorazvijenim D-Arc postupkom zavarivanja. U teorijskom dijelu najprije je opisan konvencionalni MAG postupak zavarivanja. Opisana je potrebna oprema s naglaskom na izvor struje pri kojem su detaljno obrađene strujno–naponske karakteristike. Uz izvor struje opisan je i sustav za dodavanje žice te pištolji za zavarivanje. Nadalje, predstavljen je i novorazvijeni D-Arc postupak zavarivanja kod kojeg je najveća pažnja posvećena načinu prijenosa metala. Tako je detaljno opisan prijenos metala zakopanim električnim lukom te njegova stabilizacija pri visokim vrijednostima struje. Za kraj su opisane nepravilnosti koji se najčešće javljaju u procesima provedenima u eksperimentu. U eksperimentalnom dijelu rada detaljno je opisana priprema sučeljenih spojeva od konstrukcijskog čelika kvalitete S355 debljine 19 mm i oprema za MAG i D-Arc postupak kojom su ti spojevi zavareni. Na zavarenim uzorcima provedeno je radiografsko ispitivanje, ispitivanja mikrostrukture i makrostrukture te tvrdoća. Na kraju su analizirani dobiveni rezultati te je dan zaključak o izboru optimalnog procesa zavarivanja za pripremljene uzorke.

Abstract (english)

In this thesis comparative analysis of welded joints welded by conventional MAG and newly developed D-Arc welding process is described. In the theoretical part, primarily, conventional MAG proces is described. Descriptions of equipment are given, with the emphasis on the power source and its static and dynamic characteristics. Wire supply and welding guns are also described. Furthermore, newly developed D-Arc welding process is presented with maximum attention to the metal transfer. Metal transfer with buried arc and its stabilization at high current is described in detail. At the end, possible irregularities of welding joints are presented. In the experimental part of the thesis, preparation of butt welded joints made of S355 construction steel and equipment for MAG and D-Arc welding process are described in detail. Radiography, microstructural and macrostructural analysis and hardness measurements were performed on the specimens. At the end, the obtained results were analyzed and conclusion on the optimal welding process for the prepared specimens is given.

• Keywords: MAG; D-Arc; dinamička i statička karakteristika; zakopani električni luk; greške
• Keywords (english): MAG; D-Arc; dynamic and static characteristic; buried arc; irregularities
• Language: croatian
• URN:NBN: urn:nbn:hr:235:350098
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 22:36:27