Kuponyera mchenga wodziumitsa kapena kuponya mchenga wosaphika ndi mtundu umodzi wa mchenga wokutidwa ndi utomoni kapena.Chipolopolo nkhungu castings ndondomeko. Imagwiritsa ntchito zida zomangira mankhwala kuti zisakanize ndi mchenga ndikuzilola kuti zikhale zolimba paokha. Chifukwa palibe njira yotenthetsera isanakwane, njirayi imatchedwanso kuponya mchenga wosaphika.
Dzina loti osaphika limachokera ku mafuta owumitsa okosijeni omwe adapangidwa ndi a Swiss koyambirira kwa 1950, ndiye kuti, mafuta owuma monga mafuta a linseed ndi mafuta a tung amawonjezedwa ndi ma desiccants achitsulo (monga cobalt naphthenate ndi aluminium naphthenate) ndi oxidant. (monga potaziyamu permanganate kapena sodium perborate, etc.). Pogwiritsa ntchito njirayi, mchenga wa mchenga ukhoza kuumitsidwa kuti ukhale wolimba kuti utulutse nkhungu pambuyo posungidwa kwa maola angapo kutentha. Ankatchedwa kutentha kwa chipinda (Air Set), kudzilimbitsa (Self Set), kuzizira kozizira (Cold Set) ndi zina zotero. Koma sichinafike pakudziumitsa kwenikweni, ndiko kuti, palibe kuphika (Palibe Kuphika), chifukwa nkhungu yomalizidwa (pachimake) iyenera kuwumitsidwa kwa maola angapo isanayambe kutsanulira kuti ikwaniritse kuumitsa kwathunthu.
"Mchenga wodziumitsa" ndi mawu omwe adawonekera pambuyo poti makampani opanga zida adatengera zomangira mankhwala, ndipo tanthauzo lake ndi:
1. Mu ndondomeko ya kusakaniza mchenga, kuwonjezera pa kuwonjezera binder, wothandizira (oumitsa) omwe amatha kuumitsa binder amawonjezeredwanso.
2. Pambuyo popanga ndi kupanga pakati ndi mchenga wotere, palibe mankhwala (monga kuyanika kapena kuwomba mpweya woumitsa) amagwiritsidwa ntchito kuumitsa nkhungu kapena pachimake, ndipo nkhungu kapena pachimake zimatha kuuma zokha.
Kuchokera kumapeto kwa zaka za m'ma 1950 mpaka kumayambiriro kwa zaka za m'ma 1960, njira yeniyeni yodziumitsa yokha popanda uvuni inayamba kupangidwa pang'onopang'ono, yomwe ndi asidi-cured (catalyzed) furan resin kapena phenolic resin self-hardening njira, ndi njira yodziumitsa yokha ya mafuta a urethane. 1965. Njira yodziletsa ya phenolurethane idayambitsidwa mu 1970, ndi phenolic ester. kudziletsa kuumitsa njira anaonekera mu 1984. Choncho, lingaliro la "mchenga kudzikonda" likugwira ntchito kwa onse owuma mchenga mchenga, kuphatikizapo kudzikonda atakhala mafuta mchenga, madzi galasi mchenga, simenti mchenga, zotayidwa mankwala Bonded mchenga ndi utomoni mchenga.
Monga mchenga wodziumitsa wozizira, mchenga wa furan resin ndiye mchenga wakale kwambiri komanso womwe ukugwiritsidwa ntchito kwambiri pakupanga mchenga muChina maziko. Kuchuluka kwa utomoni wowonjezeredwa mumchenga wowumba nthawi zambiri kumakhala 0.7% mpaka 1.0%, ndipo kuchuluka kwa utomoni wowonjezera mumchenga wapakati nthawi zambiri kumakhala 0.9% mpaka 1.1%. Zomwe zili mu aldehyde yaulere mu furan resin ndizochepera 0.3%, ndipo mafakitale ena atsikira pansi pa 0.1%. M'malo oyambira ku China, mchenga wowumitsa utomoni wa furan wafika pamlingo wapadziko lonse lapansi mosasamala kanthu za njira yopangira komanso mawonekedwe apamwamba a castings.
Mukasakaniza mchenga wapachiyambi (kapena mchenga wobwezeretsedwa), utomoni wamadzimadzi ndi chothandizira chamadzimadzi mofanana, ndikuzidzaza mu bokosi lalikulu (kapena bokosi la mchenga), ndiyeno mumangirire kuti liwumitse mu nkhungu kapena nkhungu mu bokosi lalikulu (kapena mchenga bokosi). ) pa kutentha kwa chipinda, nkhungu yoponyera kapena chitsulo choponyera chinapangidwa, chomwe chimatchedwa self-hardening cold-core box modeling (pachimake), kapena njira yodzipangira yokha (core). Njira yodziumitsa yokha imatha kugawidwa mu acid-catalyzed furan resin ndi phenolic resin mchenga kudziletsa njira, urethane resin mchenga kudziletsa kuumitsa njira ndi phenolic monoester kudziletsa kuumitsa njira.
Makhalidwe oyambira odzipangira okha owuma amawumbidwa ndi awa:
1) Sinthani kulondola kwa dimensionalzoponyandi kukhaula pamwamba.
2) Kuuma kwa nkhungu (pachimake) mchenga sikufuna kuyanika, komwe kungapulumutse mphamvu, komanso matabwa otsika mtengo kapena mabokosi apulasitiki ndi ma templates angagwiritsidwenso ntchito.
3) Mchenga wodzilimbitsa wokhawokha ndi wosavuta kuphatikizika ndikugwa, zosavuta kuyeretsa zotayira, ndipo mchenga wakale ukhoza kubwezeredwa ndikugwiritsanso ntchito, zomwe zimachepetsa kwambiri kulimba kwa ntchito yopanga pachimake, kufananiza, kugwa kwa mchenga, kuyeretsa ndi maulalo ena, ndi ndikosavuta kuzindikira makina kapena makina.
4) Gawo lalikulu la utomoni mumchenga ndi 0.8% ~ 2.0% yokha, ndipo mtengo wathunthu wazopangira ndizotsika.
Chifukwa njira yodzipangira yokhayokha ili ndi ubwino wambiri womwe tatchula pamwambapa, kuponyedwa kwa nkhungu ya mchenga sikumangogwiritsidwa ntchito popanga pachimake, komanso kumagwiritsidwa ntchito popanga. Ndikoyenera makamaka kupanga chidutswa chimodzi ndi kupanga batch yaying'ono, ndipo imatha kupanga chitsulo choponyedwa, chitsulo choponyedwa ndizopanda ferrous alloy castings. Malo ena opangira zinthu ku China alowa m'malo mwa nkhungu za mchenga wouma, zoumba za mchenga wa simenti, ndikusintha pang'ono za mchenga wa magalasi amadzi.
Nthawi yotumiza: Jan-21-2021