1. Kev siv vuam tsis xws luag hauv Q355Pegho Welds
(1) Hydrogen -}} Tsis muaj kev tawg (HIC) - qhov tsis tshua nyiam
Yam ua dab tsi: Cov kab nrib pleb zoo (hloov chaw lossis nruab nrab) uas ua rau hauv Weld hlau lossis koob rau hnub tom qab muaj kev ntxhov siab thiab muaj kev cuam tshuam ntau dua.
Ua:
Hydrogen cov ntsiab lus los ntawm "qias neeg" vuam cov ntaub ntawv (piv txwv li, noo Electrodes, tiv thaiv cov pa tiv thaiv roj zoo li co₂ nrog noo noo).
Q355GNH's Cu/Cr-rich composition increases its sensitivity to hydrogen embrittlement.
Sai sai txias tom qab vuam (piv txwv li, hauv ib puag ncig txias) ntxiab hydrogen hauv microstructure, nce kev tsav tsheb nrawm.
(2) Tsis muaj fusion (LOF) thiab tsis muaj qhov nkag (LOP)
Yam ua dab tsi: Tsis muaj qhov khoob ntawm Weld hlau thiab lub hauv paus hlau (LOF) lossis tsis tiav kev nkag mus los ntawm kev sib koom tes thickness (LOP), tsis muaj zog} cov kabmob muaj peev xwm.
Ua:
Cov tswv yim tsis txaus ua tshav kub (piv txwv li, qis vuam tam sim no, kev tawm tsam nrawm) - Q355 Kwm Kev Lom Zem Me ntsis ntxiv rau cov cua sov ntau dua li cov cua sov ntau dua li cov roj hlau kom zoo dua li cov hlau.
Kev sib koom ua tsis zoo haum ...-}} li (piv txwv li, kev ua haujlwm ntau dhau ntawm cov hauv paus hniav / hlau lub kaum sab xis.
(3) cov noob nplej zom rau hauv lub taub hau haz - degrades toughness
Yam ua dab tsi: Lub haz (nyob ib sab rau lub weld) tsim cov ntxhib ferrite lossis bainite furite lossis beG, tej yam kev cuam tshuam rau -40℃poob qis dua 27J).
Ua:
Kev tshav kub ntau dhau (piv txwv li, siab mus ncig ua si tam sim no, qeeb mus rau qhov kub (saum ntuj 950 degree) ua rau uncontrollably.
Q355gnh's li qub microstructure yog rhiab rau cua sov; overheating cuam tshuam nws zoo ferrite - pumbite tshuav nyiaj li cas.
(4) corrosion tiv taus deentration - ib "zais" tsis xws luag
Yam ua dab tsi: Lub chaw weld (suav nrog weld hlau thiab haz) ua cenrodes sai dua li cov kav dej tsis sib xws - ib qho tsis muaj xeb nplua nuj - tsis ua haujlwm ntawm Q355Nghhnh's corepering function.
Ua:
Mismatched muab tub rog hlau (piv txwv li, siv cov pa roj carbon hlau tsis siv hluav taws xob- Cov neeg muaj CU / CR / NI los ua ib txheej xeb.
Tshaj tawm - Weld oxidation (piv txwv li, tsis muaj cov coarse grains pawm, tsis {{adherent xeb.
2. Kev Tiv Thaiv Kev Tiv Thaiv rau txhua qhov tsis xws luag
(1) Tiv thaiv hydrogen -} indive cracking (hic)
Tswj hydrogen qhov chaw:
Cov ntaub ntawv Will: ci qis - hydrogen electrodes (piv txwv li, e5015-g rau huab cua hlau) ntawm 350-400℃rau 1-2 teev; Khw muag khoom tsis siv electrodes nyob rau hauv ib tug rhuab tuav qhov cub (80-120 degree).
Purify shielding gas: Use dry CO₂ or Ar-CO₂ (moisture content ≤50ppm); install a gas dryer if ambient humidity >60%.
Txo cov kev ntxhov siab tseem ceeb:
Preheat the base metal to 80–150°C (critical for plates >12 hli tuab los yog nyob rau hauv kub<5°C) to slow cooling and allow hydrogen escape.
Ua lus tshaj tawm - Weld ntxhov siab (550-650℃rau tuab {} {{{ntxhov siab sib koom tes sib koom tes.
Txhim kho qhov nqi txias: Siv Kev Tswj Kub Kub (Tswj 150-250℃ntawm weld kis tau) kom tsis txhob txias txias.
(2) tiv thaiv kom tsis txhob fusion / nkag mus
Kho cov lus sov sov:
Rau kev tuav cov ntawv Arc VUAM (MMA): Siv cov electrodes ntawm txoj kab uas hla 3.2-4.0 hli, 100-160A, thiab kev mus ncig ua si 8-12cm / min.
Rau roj roj hlau arc vuam (GMAW): Siv Hlau Thia inter 1.2mm, Voltage 22-26V, thiab kev mus ncig ua si 10-15cm / min.
Txhim Kho Kev Npaj Ua Ke: Ua kom cov gap 2-4mm, Bevel Angeed 60℃± (Tshem cov xeb, lossis ntsuas nrog xaim los txhuam lossis grinder).
Txhim kho cov txheej txheem welding: Tswj hwm lub electrode / hlau lub kaum sab xis ntawm 70-80℃(rau fillet welds) lossis 90℃(rau pob tw ultrasonic (rau pob tw ultrasonic); Siv "Weave" cov lus tsa suab (dav tsawg dua lossis sib npaug ntawm 3 × electrod lub taub diam) kom ntseeg tau tias tag nrho fusion.
(3) tiv thaiv kev ua kom haum
Txwv txiav cov lus qhia tshav kub: Khaws cov lus tawm thaum tshav kub tsawg dua lossis sib npaug ntawm 25kj / cm (rau cov phiaj tsawg dua lossis sib npaug nrog oversized electrodes / xaim lossis nrawm nrawm nrawm.
Siv qis - sov vuam cov txheej txheem: Prioritize GMAW or pulsed GMAW over submerged arc welding (SAW) for thin plates; SAW (high heat input) is only suitable for plates >25mm nrog post -} Weld Neverization.
Kev tswj qhov kub: Tsis txhob tshaj 300 nce qib siab - ntau dhau los txhawb kev kub ntev ntev li kub ua rau muaj qhov kub.
(4) tiv thaiv corrosion tiv taus degradation
Siv Worireing -} qib ua tub ntxhais kawm:
MMA: E5015 {{3} h (GB / T 5117) lossis E5016-G (Weathering Steel-tshwj xeeb electrodes nrog CU / CR / NI).
GMAW: ER50-g (GB / T 8110) Nrog Cu Cov Ntsiab Lus 0.20-0.50% thiab crict 0.30-0.80%.
Post -} Weld Deg Deg:
Tshem tawm Weld ci thiab swb nrog txaug lossis grinder; Hlau - txhuam lub ntsej muag weld los txhawb cov khaub ncaws tsis sib haum txheej txheej txheej.
Siv cov txheej txheem passivation (piv txwv li, Epoxy Primer) yog tias cov khoom siv yog nthuav tawm ib puag ncig hnyav (piv txwv li cov ntug dej hiav txwv) tsis pub dhau 1 lub hlis ntawm vuam.
