Gray Cast Iron Pulley ndi Sand Casting

Chitsulo chachitsulo chotuwazipolopolo nkhungu castingsndi ntchito zakutentha mankhwalandi mankhwala pamwamba.

Kujambula kwa zipolopolondondomeko amatchedwanso pre- TACHIMATA utomoni mchenga kuponya ndondomeko, otentha chipolopolo akamaumba castings kapena pachimake kuponyera ndondomeko. Zomwe zimapangidwira kwambiri ndi mchenga wa phenolic resin, womwe umakhala wokwera mtengo kuposa mchenga wobiriwira ndi furan resin. Kuphatikiza apo, mchengawu sungagwiritsidwenso ntchito.

Furan resin kudziumitsa mchenga kuponya (njira ya nobake) amagwiritsa ntchito furan resin yokutidwa mchenga kupanga nkhungu kuponyera. Pambuyo kusakaniza mchenga wapachiyambi (kapena mchenga wobwezeretsedwa), utomoni wamadzimadzi wa furan ndi chothandizira chamadzimadzi mofanana, ndikuwadzaza mu bokosi lapakati (kapena mchenga), ndiyeno mumangirire kuti likhale lolimba mu nkhungu kapena nkhungu mu bokosi lapakati (kapena mchenga). box) pa kutentha. Ndiye kuponya nkhungu kapena kuponyera pachimake anapangidwa, amene amatchedwa kudziletsa kuumitsa ozizira pachimake bokosi akamaumba (pachimake), kapena kudziletsa kuumitsa njira (pachimake).

Chifukwa nkhungu imapangidwa pa kutentha kwa chipinda ndipo palibe chifukwa chotenthetsa, kudzipangira mchenga wouma kumatchedwanso kuti palibe-bake casting process. 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.

Monga mchenga wodziumitsa wowumitsa, mchenga wa furan resin ndiye mchenga wakale kwambiri komanso womwe amagwiritsidwa ntchito kwambiri pakupanga mchenga ku China. 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.

Iron imvi, kapena chitsulo chotuwira, ndi mtundu wachitsulo chopangidwa ndi graphite microstructure. Amatchulidwa ndi mtundu wa imvi wa fracture yomwe imapanga. Chitsulo cha imvi chimagwiritsidwa ntchito popanga nyumba zomwe kuuma kwa chigawocho kuli kofunika kwambiri kuposa mphamvu zake zowonongeka, monga zitsulo zamkati za injini zoyaka moto, nyumba zapampu, matupi a valve, mabokosi amagetsi, zolemera zowerengera ndi zokongoletsera zokongoletsera. Matenthedwe apamwamba a chitsulo cha Grey cast ndi mutu wake nthawi zambiri amagwiritsidwa ntchito popanga zophikira zachitsulo ndi ma disc brake rotor.

Zomwe zimapangidwira kuti mupeze graphic microstructure ndi 2.5 mpaka 4.0% carbon ndi 1 mpaka 3% silicon polemera. Graphite amatha kutenga 6 mpaka 10% ya voliyumu yachitsulo chotuwa. Silicon ndi yofunika kupanga chitsulo imvi mosiyana ndi chitsulo choyera, chifukwa silicon ndi graphite stabilizing element mu iron cast, kutanthauza kuti amathandiza alloy kupanga graphite m'malo carbides chitsulo; pa 3% silicon pafupifupi palibe mpweya umene umakhala ndi mankhwala osakaniza ndi chitsulo.

graphite amatenga mawonekedwe a mbali zitatu za flake. M'miyeso iwiri, ngati malo opukutidwa adzawonekera pansi pa maikulosikopu, ma graphite flakes amawoneka ngati mizere yabwino. Nsonga za flakes zimagwira ntchito ngati nsonga zakale; kotero, ndi brittle. Kukhalapo kwa ma graphite flakes kumapangitsa Grey Iron kuti ikhale yosavuta kupanga chifukwa imakonda kusweka mosavuta kudutsa ma graphite flakes. Chitsulo chotuwira chimakhalanso ndi mphamvu yabwino kwambiri yonyowetsa, chifukwa chake chimagwiritsidwa ntchito kwambiri ngati maziko oyika zida zamakina.