Nekuvandudzwa kwemaindasitiri akadai sesimbi nesimbi, petrochemical industry, zvikepe uye magetsi emagetsi, zvimiro zvakashongedzwa zvinowanzokura mugwara rehukuru, hukuru-hukuru uye hurefu-parameters, uye vamwe vachiri kushanda mukupisa kwakaderera, cryogenic, corrosive media uye dzimwe nharaunda.
Nokudaro, simbi dzakasiyana-siyana dzakaderera-yakakwirira-yakasimba, masimbi epakati uye akakwirira-alloy, masimbi ane simba guru, uye zvinhu zvakasiyana-siyana zvealloy zviri kuwedzera kushandiswa. Nekudaro, nekushandiswa kweaya magiredhi esimbi uye alloys, matambudziko mazhinji matsva anounzwa mukugadzira welding, pakati peiyo yakajairika uye yakakomba zvakanyanya ndeye welding mitswe.
Kutsemuka dzimwe nguva kunoonekwa panguva yewelding uye dzimwe nguva panguva yekuiswa kana kushanda, kunonzi kunonoka kutsemuka. Nemhaka yokuti mitswe yakadaro haigoni kuonekwa mukugadzira, mitswe yakadaro ine ngozi zvikuru. Kune akawanda marudzi eakatsemuka anogadzirwa muwelding process. Zvinoenderana netsvagiridzo yazvino, zvinoenderana nehunhu hwekutsemuka, vanogona kukamurwa zvakaenzana muzvikamu zvishanu zvinotevera:
1. Mutswe unopisa
Kuputika kunopisa kunogadzirwa pakupisa kwakanyanya panguva yewelding, saka kunonzi kupisa kunopisa. Zvichienderana nemidziyo yesimbi inosungirirwa, chimiro, tembiricha yemhando uye zvikonzero zvikuru zvezvakagadzirwa zvinopisa zvinoputika zvakasiyanawo. Nokudaro, kuputika kunopisa kwakakamurwa kuva mapoka matatu: crystallization cracks, liquefaction cracks uye polygonal cracks.
1. Crystal inotsemuka
Muchikamu chekupedzisira chekristallisation, iyo firimu yemvura inoumbwa neiyo yakaderera vhoriyamu eutectic inonetesa kubatana pakati pezviyo, uye kutsemuka kunoitika pasi pechiito chekushushikana kwekushushikana.
Inonyanya kuitika mumagetsi e carbon simbi uye yakaderera-alloy simbi ine tsvina yakawanda (yakakwira yesarufa, phosphorus, iron, kabhoni, uye silicon) uye mawelds e single-phase austenitic simbi, nickel-based alloys uye mamwe aruminiyamu alloys. pakati. Mumamiriro ega ega, kuputika kwekristalline kunogonawo kuitika munzvimbo yakakanganiswa nekupisa.
2. High tembiricha liquefaction mutswe
Pasi pechiito chekushisa kwepamusoro kweiyo welding thermal cycle, remelting inoitika pakati penzvimbo yakakanganiswa nekupisa uye zvidimbu zve-multi-layer welding, uye kuputika kunogadzirwa pasi pekuita kwekunetseka.
Inonyanya kuitika mumasimbi akasimba ane chromium uye nickel, austenitic steels, uye mamwe nickel-based alloys ari padyo neseam zone kana pakati pe-multi-layer welds. Kana zviri mukati mesarufa, phosphorus uye silicon kabhoni mubhesi resimbi uye welding waya yakakwira, tsika yekupwanya liquefaction ichawedzera zvakanyanya.
Nguva yekutumira: Kubvumbi-18-2022