Kusankhidwa ndi kukonza ma electrode a tungsten a GTAW ndikofunikira kuti muwonjezere zotsatira ndikupewa kuipitsidwa ndi kukonzanso.Zithunzi za Getty
Tungsten ndi chinthu chosowa chitsulo chomwe chimagwiritsidwa ntchito popanga ma elekitirodi a tungsten arc welding (GTAW).Njira ya GTAW imadalira kuuma komanso kukana kutentha kwa tungsten kusamutsa mawotchi apano ku arc.Malo osungunuka a tungsten ndi apamwamba kwambiri pakati pa zitsulo zonse, pa madigiri 3,410 Celsius.
Maelekitirodi osagwiritsidwa ntchitowa amabwera mosiyanasiyana komanso kutalika kwake, ndipo amapangidwa ndi tungsten kapena ma alloys a tungsten ndi zinthu zina zapadziko lapansi zomwe sizipezeka ndi ma oxides.Kusankha electrode kwa GTAW kumadalira mtundu ndi makulidwe a gawo lapansi, komanso ngati alternating current (AC) kapena direct current (DC) amagwiritsidwa ntchito powotcherera.Ndi iti mwa zokonzekera zitatu zomwe mwasankha, zozungulira, zosongoka, kapena zocheperako, ndizofunikanso kukulitsa zotsatira ndikupewa kuipitsidwa ndi kukonzanso.
Elekitirodi iliyonse imakhala ndi utoto kuti ithetse chisokonezo pamtundu wake.Mtunduwu umawonekera pansonga ya elekitirodi.
Ma elekitirodi a tungsten (AWS classification EWP) ali ndi 99.50% tungsten, yomwe imakhala ndi ma elekitirodi ogwiritsidwa ntchito kwambiri kuposa ma elekitirodi onse, ndipo nthawi zambiri imakhala yotsika mtengo kuposa ma elekitirodi a aloyi.
Maelekitirodi awa amapanga nsonga yozungulira yoyera ikatenthedwa ndipo amapereka kukhazikika kwa arc kwa kuwotcherera kwa AC ndi mafunde oyenera.Tungsten yoyera imaperekanso kukhazikika kwa arc kwa AC sine wave welding, makamaka pa aluminiyamu ndi magnesium.Nthawi zambiri sagwiritsidwa ntchito pa kuwotcherera kwa DC chifukwa sichimapereka chiyambi champhamvu cha arc chogwirizana ndi thorium kapena cerium electrode.Sitikulimbikitsidwa kugwiritsa ntchito tungsten yoyera pamakina opangidwa ndi inverter;Kuti mupeze zotsatira zabwino, gwiritsani ntchito ma elekitirodi akuthwa a cerium kapena lanthanide.
Ma electrodes a thorium tungsten (AWS classification EWTh-1 ndi EWTh-2) ali ndi osachepera 97.30% tungsten ndi 0.8% mpaka 2.20% thorium.Pali mitundu iwiri: EWTh-1 ndi EWTh-2, yomwe ili ndi 1% ndi 2%, motsatana.Motsatira.Ndi ma electrode omwe amagwiritsidwa ntchito kwambiri ndipo amakondedwa chifukwa cha moyo wawo wautali komanso kugwiritsa ntchito mosavuta.Thorium imapangitsa kuti ma elekitirodi atulutsidwe bwino ndi ma elekitirodi, potero amawongolera kuyambika kwa ma arc ndi kulola kunyamula kwapakali pano.Elekitirodi imagwira ntchito pansi pa kutentha kwake kosungunuka, komwe kumachepetsa kwambiri kuchuluka kwa anthu omwe amamwa ndikuchotsa ma arc drift, potero kumapangitsa bata.Poyerekeza ndi maelekitirodi ena, ma elekitirodi a thorium amaika tungsten yocheperako mu dziwe losungunuka, motero amayambitsa kuipitsa kocheperako.
Ma elekitirodiwa amagwiritsidwa ntchito kwambiri powotcherera mwachindunji ma elekitirodi negative (DCEN) achitsulo cha kaboni, chitsulo chosapanga dzimbiri, faifi tambala ndi titaniyamu, komanso kuwotcherera kwapadera kwa AC (monga zoonda za aluminiyamu).
Panthawi yopangira, thorium imamwazikana mofanana mu electrode, yomwe imathandiza tungsten kukhalabe ndi nsonga zakuthwa pambuyo pogaya-ichi ndi mawonekedwe abwino a electrode opangira zitsulo zopyapyala.Zindikirani: Thorium imakhala ndi radioactive, choncho nthawi zonse muzitsatira machenjezo a wopanga, malangizo ndi pepala la chitetezo cha zinthu (MSDS) mukamagwiritsa ntchito.
Cerium tungsten electrode (AWS classification EWCe-2) imakhala ndi 97.30% tungsten ndi 1.80% mpaka 2.20% cerium, ndipo imatchedwa 2% cerium.Ma elekitirodi awa amachita bwino kwambiri pakuwotcherera kwa DC pamalo otsika, koma amatha kugwiritsidwa ntchito mwaluso munjira za AC.Ndi arc yake yabwino kwambiri yoyambira pa low amperage, cerium tungsten ndiyodziwika bwino pantchito monga kupanga machubu a njanji ndi mapaipi, kukonza zitsulo zamapepala, ndi ntchito yophatikiza magawo ang'onoang'ono komanso olondola.Monga thorium, imagwiritsidwa ntchito bwino pakuwotcherera chitsulo cha kaboni, chitsulo chosapanga dzimbiri, ma nickel alloys ndi titaniyamu.Nthawi zina, imatha kusintha 2% thorium electrode.Mphamvu zamagetsi za cerium tungsten ndi thorium ndizosiyana pang'ono, koma owotcherera ambiri sangathe kusiyanitsa.
Kugwiritsiridwa ntchito kwa amperage cerium elekitirodi sikovomerezeka, chifukwa amperage yapamwamba imapangitsa kuti okusayidi asunthike msanga kunsonga ya kutentha, kuchotsa zomwe zili ndi okusayidi ndikulepheretsa ubwino wa ndondomekoyi.
Gwiritsani ntchito malangizo ang'onoang'ono komanso / kapena ocheperako (pamitundu yoyera ya tungsten, cerium, lanthanum ndi thorium) pakuwotcherera kwa inverter AC ndi DC.
Ma electrodes a Lanthanum tungsten (AWS classifications EWLa-1, EWLa-1.5 ndi EWLa-2) ali ndi osachepera 97.30% tungsten ndi 0.8% mpaka 2.20% lanthanum kapena lanthanum, ndipo amatchedwa EWLa-1, EWLa-1.5 ndi EWLa-2 Lanthanum Department wa maelementi.Ma elekitirodi awa ali ndi luso loyambira la arc, kutsika kwachangu, kukhazikika kwabwino kwa arc ndi mawonekedwe abwino kwambiri olamulira-zabwino zambiri zofanana ndi ma elekitirodi a cerium.Ma electrodes a Lanthanide alinso ndi ma conductive a 2% thorium tungsten.Nthawi zina, lanthanum-tungsten imatha kusintha thorium-tungsten popanda kusintha kwakukulu kwa njira yowotcherera.
Ngati mukufuna kukulitsa luso la kuwotcherera, lanthanum tungsten elekitirodi ndiye chisankho chabwino.Ndioyenera AC kapena DCEN okhala ndi nsonga, kapena atha kugwiritsidwa ntchito ndi magetsi a AC sine wave.Lanthanum ndi tungsten akhoza kukhala lakuthwa nsonga bwino kwambiri, amene ndi mwayi kuwotcherera zitsulo ndi zitsulo zosapanga dzimbiri pa DC kapena AC ntchito lalikulu yoweyula magetsi.
Mosiyana ndi thorium tungsten, ma electrode awa ndi oyenera kuwotcherera kwa AC ndipo, monga ma elekitirodi a cerium, amalola kuti arc iyambike ndikusungidwa pamagetsi otsika.Poyerekeza ndi tungsten koyera, chifukwa chopatsidwa elekitirodi kukula, Kuwonjezera lanthanum okusayidi kumawonjezera pazipita panopa kunyamula mphamvu pafupifupi 50%.
Zirconium tungsten electrode (AWS classification EWZr-1) ili ndi osachepera 99.10% tungsten ndi 0.15% mpaka 0.40% zirconium.Electrode ya zirconium tungsten imatha kupanga arc yokhazikika ndikuletsa sipatter ya tungsten.Ndibwino kusankha kuwotcherera kwa AC chifukwa imakhala ndi nsonga yozungulira komanso kukana kuipitsidwa kwambiri.Mphamvu yake yonyamula pano ndi yofanana kapena yokulirapo kuposa thorium tungsten.Sitikulimbikitsidwa kugwiritsa ntchito zirconium pa kuwotcherera kwa DC muzochitika zilizonse.
Ma elekitirodi osowa padziko lapansi a tungsten electrode (AWS classification EWG) ali ndi zowonjezera zosaneneka zapadziko lapansi kapena zosakanikirana za ma oxides osiyanasiyana, koma wopanga amayenera kuwonetsa chowonjezera chilichonse ndi kuchuluka kwake pa phukusi.Malingana ndi zowonjezera, zotsatira zomwe mukufuna zingaphatikizepo kupanga arc yokhazikika panthawi ya AC ndi DC, moyo wautali kuposa thorium tungsten, kutha kugwiritsa ntchito ma electrode ang'onoang'ono ang'onoang'ono pa ntchito yomweyi, ndi kugwiritsa ntchito ma electrode a kukula kofanana Pakali pano, ndi sipatter yochepa ya tungsten.
Pambuyo posankha mtundu wa electrode, sitepe yotsatira ndiyo kusankha kukonzekera komaliza.Zosankha zitatuzi ndi zozungulira, zosongoka komanso zocheperako.
Nsonga yozungulira imagwiritsidwa ntchito ngati ma elekitirodi a tungsten ndi zirconium ndipo imalimbikitsidwa panjira za AC pamakina a sine wave ndi makina amtundu wa GTAW.Kuti muthane bwino kumapeto kwa tungsten, ingogwiritsani ntchito mphamvu ya AC yomwe ikulimbikitsidwa kuti ikhale ndi ma electrode awiri (onani Chithunzi 1), ndipo mpira udzapangidwa kumapeto kwa electrode.
Kuzungulira kwa malekezero ozungulira sayenera kupitirira nthawi 1.5 kukula kwa electrode (mwachitsanzo, electrode 1/8-inch iyenera kupanga mapeto a 3/16-inch).Malo okulirapo kumapeto kwa electrode amachepetsa kukhazikika kwa arc.Ikhozanso kugwa ndikuyipitsa chowotcherera.
Malangizo ndi/kapena nsonga zocheperako (za mtundu wa tungsten, cerium, lanthanum ndi thorium) amagwiritsidwa ntchito mu inverter AC ndi DC kuwotcherera.
Popera tungsten bwino, gwiritsani ntchito gudumu lopera lomwe limapangidwira pogaya tungsten (kupewa kuipitsidwa) ndi gudumu lopera lopangidwa ndi borax kapena diamondi (kupewa kuuma kwa tungsten).Zindikirani: Ngati mukupera thorium tungsten, chonde onetsetsani kuti mukuwongolera ndi kusonkhanitsa fumbi;mphero ili ndi mpweya wokwanira wokwanira;ndi kutsatira machenjezo opanga, malangizo ndi MSDS.
Pogaya tungsten molunjika pa gudumu pa ngodya ya digirii 90 (onani Chithunzi 2) kuti muwonetsetse kuti zizindikiro zopera zimakulirakulira kutalika kwa electrode.Kuchita zimenezi kumachepetsa kupezeka kwa zitunda pa tungsten, zomwe zingayambitse kugwedezeka kwa arc kapena kusungunuka mu dziwe la weld, zomwe zimapangitsa kuti zisawonongeke.
Nthawi zambiri, mukufuna kugaya taper pa tungsten kuti isapitirire 2.5 kuchuluka kwa ma electrode (mwachitsanzo, pa electrode 1/8-inch, pansi ndi mainchesi 1/4 mpaka 5/16).Kupera tungsten mu chulucho kungathandize kuti kusintha kwa arc kukhale kosavuta, ndikupanga arc yokhazikika, kuti mupeze ntchito yabwino yowotcherera.
Mukawotchera pazida zopyapyala (0.005 mpaka 0.040 mainchesi) pamlingo wocheperako, ndi bwino kugaya tungsten mpaka pang'ono.Nsonga imalola kuwotcherera kwapano kuti kufalikira mu arc yolunjika ndipo kumathandiza kupewa kusinthika kwazitsulo zopyapyala monga aluminiyamu.Sitikulimbikitsidwa kugwiritsa ntchito tungsten yosongoka pamapulogalamu apamwamba aposachedwa chifukwa chapamwamba kwambiri chimaphulitsa nsonga ya tungsten ndikuyambitsa kuipitsidwa kwa dziwe la weld.
Kwa mapulogalamu apamwamba amakono, ndi bwino kugaya nsonga yodulidwa.Kuti mupeze mawonekedwe awa, tungsten ndi malo oyamba ku taper yomwe tafotokoza pamwambapa, kenako ndikuyika mpaka mainchesi 0.010 mpaka 0.030.Lathyathyathya pansi kumapeto kwa tungsten.Malo athyathyathya awa amathandizira kuti tungsten isadutse mu arc.Zimalepheretsanso mapangidwe a mipira.
WELDER, yemwe kale ankadziwika kuti Practical Welding Today, amasonyeza anthu enieni omwe amapanga zinthu zomwe timagwiritsa ntchito ndikugwira ntchito tsiku lililonse.Magazini iyi yakhala ikugwira ntchito yowotchera zinthu ku North America kwa zaka zoposa 20.
Nthawi yotumiza: Aug-23-2021