Welders feem ntau ntsib qhov tsis paub meej txog preheating Q355GNH Corten Steel- qee qhov hla nws kom txuag tau sijhawm, thaum lwm tus preheat yam tsis tsim nyog rau txhua qhov tuab, nce nqi. Preheating yog qhov tseem ceeb rau kev tiv thaiv cov kab nrib pleb hauv siab - lub zog steels, tab sis Q355GNH qhov sib npaug ntawm cov khoom sib npaug thiab cov ductility ua rau nws muaj cai, tsis tas yuav tsum tau ua. Qhov kev xaiv tsis raug tuaj yeem ua rau cov vuam tsis ua haujlwm, cov pob qij txha tawg, lossis kev siv dag zog tsis zoo. Yog li, thaum twg Q355GNH xav tau preheating ua ntej vuam, thiab dab tsi yog cov lus qhia tseem ceeb? Raws li GB / T cov qauv thiab kev siv vuam, cov lus teb tseem ceeb yog qhov tseeb:Q355GNH Corten Steel tsis xav tau preheating rau feem ntau vuam scenarios; Nws tsuas yog xav tau rau cov phaj tuab, qis- qhov kub thiab txias ib puag ncig, lossis cov pob qij txha nyuaj kom tsis txhob muaj qhov txias txias. Hauv qab no yog cov lus qhia yooj yim, ua tau zoo.
Vim li cas Preheating Matters (thaum nws xav tau)
Preheating Q355GNH ua haujlwm rau ib lub hom phiaj tseem ceeb: tiv thaiv hydrogen-induced txias tawg, uas tsim thaum welds txias sai heev. Nws ua haujlwm los ntawm:
Ua kom qhov txias txias ntawm qhov vuam thiab cua sov- thaj tsam cuam tshuam (HAZ), tso cai rau hydrogen khiav ua ntej cov kab nrib pleb.
Txo cov kev ntxhov siab nyob hauv qhov sib koom ua ke, uas txo qis qhov kev pheej hmoo ntawm kev tawg tawg yooj yim -tshwj xeeb yog qhov tseem ceeb rau Q355GNH qhov ntsuas kub tsawg -.
Nco tseg: Q355GNH cov ntsiab lus qis qis (tsawg dua lossis sib npaug li 0.18%) thiab taug qab Ni / Mn ntxiv txhim kho ductility, yog li nws tiv taus cov kab mob khaub thuas ntau dua li siab dua - lub zog steels.
Thaum Preheating tsis xav tau (Feem ntau Scenarios)
Rau 70% ntawm Q355GNH vuam tej yaam num, preheating yog tsis tsim nyog -txuag lub sij hawm yam tsis muaj kev cuam tshuam weld zoo:
Cov xwm txheej: Phaj thickness Tsawg dua los yog sib npaug li 16 hli; ambient vuam kub siab dua los yog sib npaug rau 15 degree; yooj yim pob qij txha (lub taub qab, fillet welds); siv tsawg-hydrogen consumables (piv txwv li, E5015, ER50-6).
Piv txwv: Vuam 6-14mm Q355GNH rau sab nraum zoov cladding, guardrails, los yog lub teeb structural Cheebtsam.
Vim li cas: nyias daim hlau dissipate cua sov tusyees, thiab Q355GNH qhov ductility tiv thaiv kom txias sai -induced cracks thaum siv cov consumables.
Thaum Preheating yog MANDATORY (Critical Scenarios)
Hla preheating nyob rau hauv cov rooj plaub no ua rau muaj kev pheej hmoo tawg ntau heev - ua raws li cov lus qhia no kom nyab xeeb, siab -welds zoo:
1. Cov phaj tuab (＞ 16mm)
Preheating kub: 80-120℃(tseem tsawg kawg yog 50mm los ntawm qhov sib koom ua ke).
Lub Ntsiab Lus Qhia: Ua kom muaj cua sov zoo ib yam thoob plaws hauv cheeb tsam sib koom ua ke - zam qhov chaw kub kub.
2. Tsawg-Tsuas Vuam (tsawg dua lossis sib npaug li 15 degree)
Preheating kub: 100-150 degree, txawm rau nyias daim hlau (tsawg dua los yog sib npaug li 16 hli).
Yog vim li cas: Cov cua txias ambient kub ua kom cov vuam txias, ua kom cov cuab yeej hydrogen thiab kev pheej hmoo tawg - tseem ceeb rau Q355GNH qhov qis - qhov kub thiab txias qhov project siv.
3. Complex los yog siab -Stress Joints
Cov xwm txheej: T-cov pob qij txha, cov pob qij txha, lossis cov pob qij txha uas txwv kev nthuav dav (piv txwv li, cov txheej txheem kaw).
Preheating Kub: 80-120℃kom txo tau kev ntxhov siab thaum lub caij txias.
Tswv yim Preheating tswv yim (yog tias xav tau)
Siv cov cuab yeej tsim nyog: Oxy-acetylene torches (rau thaj chaw me me) lossis lub tshuab hluav taws xob tiv thaiv hluav taws xob (rau cov txheej txheem preheating ntawm cov phaj loj).
Saib xyuas qhov kub thiab txias: Siv qhov ntsuas kub (piv txwv li, thermocouple) kom tsis txhob muaj cua sov (＞ 200 degree), uas tuaj yeem degrade Q355GNH cov khoom siv kho tshuab.
Tshaj tawm -preheating: Weld tam sim ntawd tom qab ncav cuag qhov kub ntawm lub hom phiaj- tsis txhob cia lub phaj txias hauv qab qhov kub ntawm preheating ua ntej vuam.
Hauv cov ntsiab lus, Q355GNH Corten Steel tsis tshua xav tau preheating rau cov qauv vuam xwm txheej. Tsuas yog ua kom sov thaum ua haujlwm nrog cov phaj tuab, qhov txias txias, lossis cov pob qij txha nyuaj- ua raws li 80-150℃ntau yam kom ntseeg tau tias tsis muaj kab nrib pleb, muaj zog welds thaum zam kev siv dag zog thiab cov nqi tsis tsim nyog.
