Kodi kuwotcherera kwa ng'anjo ya vacuum brazing ndi chiyani?

Brazing mu ng'anjo ya vacuum ndi njira yatsopano yowotchera popanda kusuntha pansi pa vacuum. Chifukwa chowotchacho chimakhala pamalo opanda zingwe, kuwonongeka kwa mpweya pa chogwiriracho kumatha kuthetsedwa bwino, kotero kuti brazing imatha kuchitidwa bwino popanda kugwiritsa ntchito flux. Amagwiritsidwa ntchito kwambiri popangira zitsulo ndi ma alloys omwe ndi ovuta kulimba, monga aluminium alloy, titaniyamu alloy, superalloy, alloy refractory ndi ceramics. Mgwirizano wa brazed ndi wowala komanso wandiweyani, wokhala ndi zida zabwino zamakina komanso kukana dzimbiri. Zida zopangira vacuum nthawi zambiri sizimagwiritsidwa ntchito powotcherera singano zachitsulo cha kaboni ndi chitsulo chochepa cha alloy.

Zida zowotchera mu ng'anjo ya vacuum zimapangidwa makamaka ndi ng'anjo ya vacuum brazing ndi vacuum system. Pali mitundu iwiri ya ng'anjo za vacuum brazing: poyatsira moto ndi poyatsira moto wozizira. Mitundu iwiri ya ng'anjo imatha kutenthedwa ndi gasi kapena kutentha kwamagetsi. Atha kupangidwa kukhala ng'anjo yowongoleredwa m'mbali, ng'anjo yokwera pansi kapena ng'anjo yokwera pamwamba (mtundu wa Kang), ndipo makina otsekemera amatha kukhala onse.

Vacuum system makamaka imaphatikizapo vacuum unit, vacuum valve, vacuum valve, ndi zina zotere. Vutoli nthawi zambiri limapangidwa ndi pampu yolumikizira mafuta komanso pampu yolumikizira mafuta. Pampu yamakina yogwiritsira ntchito kamodzi imatha kupeza zochepa kuposa 1.35 × Vacuum degree ya 10-1pa level. Kuti mupeze vacuum yayikulu, pampu yolumikizira mafuta iyenera kugwiritsidwa ntchito nthawi yomweyo, yomwe imatha kufika 1.35 panthawiyi × Vacuum degree ya 10-4Pa level. Kuthamanga kwa mpweya mu dongosolo kumayesedwa ndi vacuum gauge.

Kuwotcha mu ng'anjo ya vacuum ndikuwotcha mu ng'anjo kapena chipinda chowotcha ndi mpweya wotulutsidwa. Ndikoyenera kwambiri kulumikiza zilumikizidwe zazikulu komanso zopitilira. Ndiwoyeneranso kulumikiza zitsulo zapadera, kuphatikizapo titaniyamu, zirconium, niobium, molybdenum ndi tantalum. Komabe, vacuum brazing ilinso ndi zovuta izi:

① Pansi pa vacuum, zitsulo ndizosavuta kusuntha, kotero kuti vacuum brazing sayenera kugwiritsidwa ntchito ngati zitsulo zoyambira ndi zowotcherera zowotcherera. Ngati ndi kotheka, njira zovuta zofananira ziyenera kutsatiridwa.

② Vacuum brazing imakhudzidwa ndi kuuma kwapamwamba, mtundu wa msonkhano komanso kulolerana koyenera kwa magawo olimba, ndipo imakhala ndi zofunika kwambiri pa malo ogwirira ntchito komanso mulingo waukadaulo wa ogwira ntchito.

③ Zida za vacuum ndizovuta, zokhala ndi ndalama zambiri nthawi imodzi komanso mtengo wokonza.

Kotero, momwe mungagwiritsire ntchito ndondomeko ya brazing mu ng'anjo ya vacuum? Mukawotchera ng'anjo yamoto, ikani chowotchereracho ndi kuwotcherera mu ng'anjo (kapena mu chidebe chowotcha), kutseka chitseko cha ng'anjo (kapena kutseka chivundikiro cha chidebe choyaka moto), ndikutsuka musanayambe kutentha. Yambitsani mpope wamakina kaye, tembenuzirani chiwongolero chikafika pa 1.35pa, kutseka njira yolunjika pakati pa mpope wamakina ndi ng'anjo yoyaka moto, pangani payipi yolumikizidwa ndi ng'anjo yoyaka moto kudzera papampu yolumikizira, gwirani ntchito pakanthawi kochepa podalira pampu yamakina ndi mpope wothira, kupopera ng'anjo yoyaka moto, kutentha koyambira ndikuyamba kutentha.

Pa ndondomeko yonse ya kutentha ndi Kutentha, ndi zingalowe wagawo ntchito mosalekeza kukhala zingalowe digiri mu ng'anjo, kuthetsa mpweya kutayikira pa mawonekedwe osiyanasiyana vacuum dongosolo ndi ng'anjo yamoto, amasulidwe mpweya ndi nthunzi madzi adsorbed ndi ng'anjo khoma, fixture ndi weldment, ndi volatilization, mpweya woona kuti kuchepetsa zitsulo. Pali mitundu iwiri ya vacuum brazing: high vacuum brazing ndi vacuum pang'ono (zapakati vacuum) brazing. High vacuum brazing ndi yoyenera kwambiri pakuwotcha chitsulo choyambira chomwe oxide ndizovuta kuwonongeka (monga nickel base superalloy). Kutsekera pang'ono kwa vacuum kumagwiritsidwa ntchito nthawi zomwe chitsulo choyambira kapena solder chimagwedezeka pansi pa kutentha kwamphamvu komanso mpweya wambiri.

Pamene njira zodzitetezera ziyenera kuchitidwa kuti zitsimikizidwe kuti ndizoyera kwambiri, njira yoyeretsera vacuum iyenera kutsatiridwa musanawume hydrogen brazing. Mofananamo, kugwiritsa ntchito njira yoyeretsera haidrojeni kapena gasi musanayambe kupopera vacuum kumathandizira kupeza zotsatira zabwino pakuwotcha kwa vacuum.