I-Brazing esithandweni se-vacuum iyindlela entsha yokubhula ngaphandle kwe-flux ngaphansi kwezimo ze-vacuum. Ngenxa yokuthi i-brazing isendaweni ye-vacuum, umphumela oyingozi womoya ku-workpiece ungaqedwa ngokuphumelelayo, ngakho-ke i-brazing ingenziwa ngempumelelo ngaphandle kokusebenzisa i-flux. Isetshenziselwa ikakhulukazi izinsimbi zokubethela kanye nama-alloys okunzima ukuwaqinisa, njenge-aluminium alloy, i-titanium alloy, i-superalloy, i-refractory alloy kanye ne-ceramics. Ijoyinti le-brazed ligqamile futhi liminyene, linezici ezinhle zemishini nokumelana nokugqwala. Imishini ye-vacuum brazing ngokuvamile ayisetshenziselwa ukushisela inaliti ye-carbon steel ne-low alloy steel.
Imishini yokubraza esithandweni se-vacuum ikakhulukazi yakhiwe isithando somlilo se-vacuum kanye nesistimu ye-vacuum. Kunezinhlobo ezimbili ze-vacuum brazing Furnaces: indawo yomlilo eshisayo nendawo yomlilo ebandayo. Lezi zinhlobo ezimbili zomlilo zingashiswa ngegesi yemvelo noma ukushisa kukagesi. Angaklanywa abe isithando somlilo esibekwe eceleni, isithando somlilo esibekwe ngezansi noma isakhiwo somlilo esibekwe phezulu (uhlobo lwe-Kang), futhi isistimu ye-vacuum ingaba yindawo yonke.
Isistimu ye-vacuum ngokuyinhloko ihlanganisa iyunithi ye-vacuum, ipayipi le-vacuum, i-vacuum valve, njll. Iyunithi yevacuum ivamise ukwakhiwa ngephampu yemishini ye-rotary vane kanye nephampu yokusabalalisa uwoyela. Iphampu yemishini esetshenziswa kanye kuphela ingathola ngaphansi kuka-1.35 × Idigri yeVacuum yeleveli engu-10-1pa. Ukuze uthole i-vacuum ephezulu, ipompo yokusabalalisa amafutha kufanele isetshenziswe ngesikhathi esifanayo, engafinyelela ku-1.35 ngalesi sikhathi × I-vacuum degree yezinga le-10-4Pa. Ingcindezi yegesi ohlelweni ikalwa nge-vacuum gauge.
I-Brazing esithandweni se-vacuum iyavutha esithandweni noma egumbini elishisayo elikhipha umoya. Ifaneleka ngokukhethekile ukubhula amalunga amakhulu futhi aqhubekayo. Ibuye ilungele ukuxhuma ezinye izinsimbi ezikhethekile, okuhlanganisa i-titanium, i-zirconium, i-niobium, i-molybdenum ne-tantalum. Kodwa-ke, i-vacuum brazing nayo inokungalungi okulandelayo:
① Ngaphansi kwezimo ze-vacuum, insimbi kulula ukuyishintshashintsha, ngakho-ke i-vacuum brazing akufanele isetshenziselwe isisekelo sensimbi nezinto eziguqukayo zokushisela i-solder. Uma kunesidingo, izinyathelo ezihambisanayo zenqubo eyinkimbinkimbi kufanele zamukelwe.
② I-vacuum brazing izwela ubulukhuni bendawo, ikhwalithi yokuhlanganisa kanye nokubekezelela okufanele kwezingxenye eziqinile, futhi inezidingo eziphakeme zendawo yokusebenza kanye nezinga lethiyori labasebenzisi.
③ Imishini ye-vacuum iyinkimbinkimbi, inotshalomali olukhulu lwesikhathi esisodwa kanye nezindleko eziphezulu zokulungisa.
Ngakho-ke, ungayisebenzisa kanjani inqubo yokubopha esithandweni somlilo? Lapho ukubrasa kwenziwa esithandweni se-vacuum, faka i-weldment nge-welding esithandweni (noma esitsheni esishisayo), vala umnyango wesithando somlilo (noma uvale isembozo sesitsha esivuthayo), futhi uhlanze ngaphambili ngaphambi kokufudumeza. Qala iphampu yomshini kuqala, vula ivalvu yokuqondisa ngemva kokuthi idigri ye-vacuum ifinyelela ku-1.35pa, vala indlela eqondile phakathi kwephampu engumshini nesithando somlilo esivuthayo, yenza ipayipi elixhunywe nesithando somlilo ngephampu yokusakaza, sebenza phakathi nesikhathi esilinganiselwe ngokuthembela empompini engumshini kanye nephampu yokusabalalisa, mpompa isithando somlilo esivuthayo, ugesi oshisayo uqalise futhi uqalise izinga lokushisa elidingekayo.
Phakathi nayo yonke inqubo yokushisa nokushisa, iyunithi ye-vacuum izosebenza ngokuqhubekayo ukugcina i-vacuum degree esithandweni somlilo, isuse ukuvuza komoya ezindaweni ezihlukahlukene zesistimu ye-vacuum nesithando somlilo esishisayo, ukukhululwa kwegesi kanye nomhwamuko wamanzi okhangiswa udonga lwesithando somlilo, ukulungiswa kanye nokushisela, kanye nokuvuza, ukwehla kwe-oxide ukuze kuncishiswe insimbi nokwehla kwensimbi. Kunezinhlobo ezimbili ze-vacuum brazing: i-vacuum brazing ephezulu kanye ne-vacuum eyingxenye (i-medium vacuum) yokubrazing. I-vacuum brazing ephezulu ifaneleka kakhulu ukubhula insimbi eyisisekelo okunzima ukuyibola i-oxide (njenge-nickel base superalloy). I-vacuum brazing eyingxenye isetshenziselwa izikhathi lapho isisekelo sensimbi noma i-solder ishintshashintsha ngaphansi kwezinga lokushisa elishisayo nezimo eziphezulu ze-vacuum.
Lapho kufanele kuthathwe izinyathelo ezikhethekile zokuqinisekisa ukuhlanzeka okuphezulu, indlela yokuhlanza i-vacuum kufanele yamukelwe ngaphambi kokufakwa kwe-hydrogen eyomile. Ngokufanayo, ukusebenzisa i-hydrogen eyomile noma indlela yokuhlanza igesi ye-inert ngaphambi kokupompa i-vacuum kuzosiza ukuthola imiphumela engcono ekubrazeni kwe-vacuum ephezulu.
Isikhathi sokuthumela: May-07-2022