Ndi chitukuko cha mafakitale monga chitsulo ndi zitsulo, makampani petrochemical, zombo ndi mphamvu yamagetsi, nyumba welded zimakonda kukula mu njira zazikulu, mphamvu ndi mkulu-parameters, ndipo ena akugwirabe ntchito kutentha otsika, cryogenic, corrosive media ndi malo ena.
Choncho, zitsulo zosiyanasiyana zotsika kwambiri zotsika kwambiri, zitsulo zapakatikati ndi zapamwamba, zitsulo zamphamvu kwambiri, ndi zipangizo zosiyanasiyana za alloy zimagwiritsidwa ntchito kwambiri.Komabe, pogwiritsa ntchito magiredi achitsulo awa ndi ma aloyi, zovuta zambiri zatsopano zimabweretsedwa popanga kuwotcherera, zomwe zimafala kwambiri komanso zowopsa kwambiri ndikuwotcherera ming'alu.
Ming'alu nthawi zina amawonekera pa kuwotcherera ndipo nthawi zina pakuyika kapena kugwira ntchito, otchedwa ming'alu yochedwa.Chifukwa ming'alu yoteroyo siidziwika popanga, ming'alu yotereyi ndi yoopsa kwambiri.Pali mitundu yambiri ya ming'alu yomwe imapangidwa powotcherera.Malinga ndi kafukufuku wamakono, malinga ndi momwe ming'aluyo imakhalira, imatha kugawidwa m'magulu asanu otsatirawa:
1. Mng'alu wotentha
Kuphulika kotentha kumapangidwa pa kutentha kwakukulu panthawi yowotcherera, choncho amatchedwa ming'alu yotentha.Malinga ndi zinthu zachitsulo kuti welded, mawonekedwe, kutentha osiyanasiyana ndi zifukwa zazikulu za kwaiye ming'alu otentha ndi osiyana.Choncho, ming'alu yotentha imagawidwa m'magulu atatu: ming'alu ya crystallization, ming'alu ya liquefaction ndi ming'alu ya polygonal.
1. Mng'alu wa kristalo
Mu gawo lotsatira la crystallization, filimu yamadzimadzi yopangidwa ndi eutectic yotsika kwambiri imafooketsa kugwirizana pakati pa mbewu, ndipo ming'alu imachitika chifukwa cha kupsinjika kwamphamvu.
Amapezeka makamaka mu ma welds a carbon steel ndi otsika aloyi zitsulo ndi zonyansa zambiri (high zili sulfure, phosphorous, chitsulo, carbon, ndi pakachitsulo) ndi welds wa single-gawo austenitic zitsulo, faifi tambala-based aloyi ndi zina zotayidwa zotayidwa. pakati.Muzochitika payekha, ming'alu ya crystalline imathanso kuchitika m'madera omwe amakhudzidwa ndi kutentha.
2. High kutentha liquefaction mng'alu
Pansi pa kutentha kwapamwamba kwa kutentha kwa kutentha, kukonzanso kumachitika pakati pa malo okhudzidwa ndi kutentha ndi zigawo za kuwotcherera kwamitundu yambiri, ndipo ming'alu imapangidwa pansi pa kupsinjika maganizo.
Zimapezeka makamaka muzitsulo zamphamvu kwambiri zomwe zimakhala ndi chromium ndi faifi tambala, zitsulo za austenitic, ndi ma alloys ena opangidwa ndi faifi pafupi ndi msoko kapena pakati pa ma welds osanjikiza ambiri.Pamene zili sulfure, phosphorous ndi pakachitsulo mpweya m'munsi zitsulo ndi kuwotcherera waya ndi mkulu, chizolowezi liquefaction akulimbana adzachuluka kwambiri.
Nthawi yotumiza: Apr-18-2022