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Cored wires combine advantages of manual arc welding with covered electrodes and those of semiautomatic and automatic welding processes with solid wires in various shielding media, i.e. gases and fluxes. They are produced in two ways, i.e.: a) by drawing filled-in tubes and b) by folding of a metal strip into a U-form which is to be filled with metals and minerals, and by subsequent shaping of the wire. Cored wires have practically the same diameters as solid wires. Their applicability to welding devices (MIG/MAG and SAW) is equal to solid wires. Cored-wires, however, are very sensitive to the feeding technique of welding machines because there is a risk of opening of the folded wire and of pouring out of the core into the house package, which leads to a nonuniform feeding and finally to a stand-still during welding. Devices for welding with cored wires should have a separate feeding device for wires made of a strip. Owing to a very simple application, cored wires made of a tube are very suitable for welding and surfacing in industry. With a filling ratio of 30% with the above-mentioned wires, very favourable results are obtained also in surfacing of stronger loaded, wear-resistant claddings. Strženske žice združujejo prednosti ročnega obločnega varjenja z oplaščenimi elektrodami s prednostmi polavtomatskh in avtomatskih postopkov varjenja z masivnimi žicami v zaščitnih medijih - plinih in pod praški. Izdelujemo jih po dveh postopkih: a) z vlečenjem polnjenih cevi in b) z zvijanjem traku v žleb, ki ga polnimo s kovinami in minerali, ter nadaljnjim oblikovanjem žice. Strženske žice iz cevi so praktično povsem enakih dimenzij kot masivne. Tudi njihova uporabnost na varilnih napravah (MIG/MAG in EPP) je povsem enakovredna masivnim žicam. Nasprotno pa so strženske žice iz traku zelo občutljive pri pogonu na varilnih strojih, ker obstaja nevarnost odpiranja zavite žice in iztresanja stržena v cevnem paketu (božirju), kar vodi do neenakomernega podajanja in zaustavljanja žice med varjenjem. Naprave za varjenje s strženskimi žicami iz traku morajo imeti poseben pogon. Zaradi zelo enostavne uporabe so strženske žice iz cevi zelo primerne za varjenja in navarjanja v industriji. Z deležem stržena, ki zavzema pri omenjenih žicah okoli 30% preseka, dosežemo zelo dobre rezultate tudi pri navarjanju bolj obremenjenih obrabno odpornih prevlek.

Submerged arc surfacing with alloyed agglomerated fluxes permits unalloyed and low-alloy structural steels to be surfaced in one layer of high-alloyed claddings. Surfacing dilution produced by fusion of the parent metal, and burn-off of alloying elements are substituted by additional alloying by means of a welding flux, which is, in the case of the above-mentioned surfacing processes, the main carrier of alloying elements for surfacing alloying. With alloyed agglomerated fluxes, it is recommendable to surface with low current intensity which ensures a minimum fusion of the parent metal and a minimum burn-off of alloying elements. Such an adjustment of welding parameters (low current intensity per wire and comparatively high welding voltage) is characteristic for submerged arc welding with multiple - wire electrode. The above-mentioned process is, therefore, very suitable, in combination with high-alloyed agglomerated fluxes, for onelayer cladding of structural steels with high-alloyed claddings. The structure of surfacings is coarsegrained due to a large molten pool. It is recommended to improve surfacings by adding nodular powder to the filler material, i.e. alloyed surfacing flux. Navarjanje pod legiranimi aglomeriranimi praški omogoča, da konstrukcijska nelegirana in malo legirana jekla enoslojno oplatimo z močno legiranimi nanosi. Razredčenje navara, ki ga povzroči taljenje osnovnega materiala, in odgorevanje legirnih elementov nadomestimo z dodatnim legiranjem preko varilnega praška, ki je pri omenjenih navarjanjih tudi glavni nosilec legirnih elementov za legiranje navara. Z legiranimi aglomeriranimi varilnimi praški je priporočljivo navarjati z nizko jakostjo varilnega toka, kar zagotavlja minimalno taljenje osnove in minimalno odgorevanje legirnih elementov. Taka nastavitev varilnih parametrov (nizka jakost toka na žico pri razmeroma visoki varilni napetosti) je značilna za varjenje pod praškom z večžično elektrodo. Omenjeni postopek je zato v kombinaciji z močno legiranimi aglomeriranimi praški zelo primeren za enoslojno oplatenje konstrukcijskih jekel z močno legiranimi prevlekami. Struktura navarov pa je zaradi velike talilne kopeli grobo zrnata. Priporočljivo je, da navare izboljšamo še z dodatki nodulatorjev v dodajni material - legirani prašek za navarjanje.