20.500.12556/RUL-139964 Faze vmesne kontrole zvarnega spoja z neporušnimi metodami Phases of intermediate control of the weld joint with non-destructive methods V zaključni nalogi so predstavljeni potek izdelave zvarjenca in neporušne metode, s katerimi se kontrolira kakovost zvarov. Tehnologija varjenja se predpiše glede na vrsto in lastnosti osnovnega materiala ter zahtev v obratovanju. V podjetju je najpogosteje uporabljen visoko produktiven način varjenja MAG, pri katerem se za zaščito obloka uporablja aktiven zaščitni plin, ki ga sestavljata mešanica Ar in CO2. Kakovost zvarnih spojev se preverja v fazah vmesne kontrole, pri čemer le-te zajemajo vizualne preiskave, preiskave s penetranti, preiskave z magnetnimi delci in ultrazvočne preiskave. Pri ultrazvočni kontroli smo ugotovili, da sta ustrezna izbira frekvence zvoka in njegov vpadni kot odločilnega pomena za ustrezno analizo dobljenih rezultatov meritev. Razlika med frekvencama zvoka 2 in 4 MHz je v prodornosti signala, ki ga pošiljamo v preizkušanec. Tako je za indikacije na večji globini ali pri večjih debelinah osnovnega materiala ustreznejša frekvenca 2 MHz. Vpadni kot zvoka pa je odvisen od debeline materiala. Tako smo ugotovili, da je 70° vpadni kot primernejši za tanjše debeline materiala, 45° kot pa za debelejše. Za kakovost končnega izdelka so faze vmesne kontrole seveda bistvenega pomena, saj lahko le v taki meri odpravimo tekoče napake ter zagotavljamo funkcionalnost izdelka ter ustrezno obratovalno dobo zvarjenega izdelka. Ugotovili smo, da so faze vmesne kontrole po zaključenem varjenju pomembne za nemoten potek nadaljnjega proizvodnega procesa in kakovost končnega produkta. The final thesis presents the production process of the weld and non-destructive methods used to control the quality of welds. Welding technology is prescribed according to the type and properties of the base material and operational requirements. MAG welding is the most used in the company. It is a highly productive welding method in which an active shielding gas consisting of mixture of Ar and CO2 is used to protect the arc. The quality of welds is checked in the intermediate control. This includes visual inspection, liquid penetrant inspection, magnetic particle inspection and ultrasonic inspection. In ultrasonic inspection we found that appropriate choice of the sound frequency and its angle are most important for the proper analyses of measurement results. The difference between 2 and 4 MHz sound frequencies lies in the penetration of signal sent to the subject. Thus, for indications at greater depth or with greater thickness of the base material a frequency 2 MHz is more appropriate. The angle of the sound sent into material depends on the thickness of the material. Thus, we found that a 70 ° angle is more suitable for thinner material thickness and 45 ° angle for thicker ones. For the quality of the final product, are phases of intermediate control are essential, because only to this extent can we eliminate errors on the product. Adequately corrected detected defects ensure a sufficiently long service life. We found that the stages of intermediate control after welding are important for the smooth running of the further production process and the quality of the final product. jekla napake v zvarnih spojih varjenje MAG neporušne preiskave zvarnih spojev vizualne preiskave preiskave s tekočimi penetranti preiskave z magnetnimi delci ultrazvočne preiskave steels welds defects MAG welding non-destructive testing of welds visual testing penetrant testing magnetic particle testing ultrasonic testing true false false [J. Račnik] Slovenski jezik Angleški jezik Zaključna naloga 2022-09-09 08:30:33 2022-09-09 08:30:37 2023-10-13 08:45:45 0000-00-00 00:00:00 2022 0 Ljubljana 0 XIV, 39 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.791.053:669.14(043.2) 244609 123758851 16879.pdf 16879.pdf 1 55D0902745D8AA7DA6201E3F9830A37C 91c3bfef7094d990b6a09d10e66e1da95435861235dab84a97f0131ae5b4b838 dccc9bf9-3008-11ed-92af-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=160615 Fakulteta za strojništvo 0 0 0