Xov xwm

txheej txheem
Workpiece → degreasing → dej ntxuav → pickling → dej ntxuav → immersion nyob rau hauv pab plating hnyav → ziab thiab preheating → kub-dip galvanizing → tiav → txias → passivation → yaug → ziab → tshuaj xyuas
(1) Degreasing
Tshuaj degreasing los yog dej-raws li hlau degreasing tus neeg saib xyuas yuav siv tau los degreasing kom txog thaum lub workpiece yog kiag li ntub dej.
(2) Pickling
Nws tuaj yeem khaws nrog H2SO4 15%, thiourea 0.1%, 40 ~ 60 ℃ lossis HCl 20%, hexamethylenetetramine 1 ~ 3g / L, 20 ~ 40 ℃. Qhov sib ntxiv ntawm corrosion inhibitor tuaj yeem tiv thaiv cov matrix los ntawm kev xeb ntau dhau thiab txo cov hydrogen nqus ntawm hlau matrix. Tsis zoo degreasing thiab pickling kev kho mob yuav ua rau tsis zoo adhesion ntawm txheej, tsis muaj zinc txheej los yog tev ntawm zinc txheej.
(3) Immersion flux
Kuj tseem hu ua tus neeg sawv cev sib txuas, nws tuaj yeem ua kom cov khoom ua haujlwm ua haujlwm ua ntej immersion plating los txhim kho kev sib raug zoo ntawm txheej txheej plating thiab substrate. NH4Cl 15% ~ 25%, ZnCl2 2.5% ~ 3.5%, 55 ~ 65 ℃, 5 ~ 10min. Txhawm rau txo NH4Cl volatilization, glycerin tuaj yeem ntxiv kom tsim nyog.
(4) Qhuav thiab preheating
Txhawm rau tiv thaiv lub workpiece los ntawm deforming vim qhov kub thiab txias thaum lub sij hawm immersion plating, thiab kom tshem tawm cov seem seem, tiv thaiv zinc tawg, ua rau zinc kua tawg, lub preheating feem ntau yog 120-180 ° C.
(5) Kub-dip galvanizing
Nws yog ib qho tsim nyog los tswj qhov kub ntawm cov zinc tov, lub sij hawm ntawm dipping thiab ceev ntawm lub workpiece raug tshem tawm ntawm zinc tov. Qhov kub thiab txias tsis dhau, qhov fluidity ntawm zinc kua yog tsis zoo, lub txheej yog tuab thiab tsis sib xws, nws yooj yim los tsim sagging, thiab cov tsos tsis zoo; Qhov kub thiab txias, qhov fluidity ntawm zinc kua yog qhov zoo, cov kua zinc yog ib qho yooj yim kom cais tawm ntawm lub workpiece, thiab qhov tshwm sim ntawm sagging thiab wrinkles yog txo. Muaj zog, nyias txheej, zoo li zoo, kev ua haujlwm siab; Txawm li cas los xij, yog tias qhov kub thiab txias dhau lawm, lub workpiece thiab lub lauj kaub zinc yuav raug puas ntsoog, thiab ntau cov zinc dross yuav raug tsim, uas yuav cuam tshuam rau qhov zoo ntawm zinc dipping txheej thiab noj ntau cov zinc. Nyob rau tib lub sij hawm, lub immersion plating lub sij hawm ntev thiab lub plating txheej yog tuab. Thaum tib lub thickness yuav tsum tau ntawm qhov sib txawv kub, nws yuav siv sij hawm ntev rau high-temperature immersion plating. Txhawm rau tiv thaiv qhov kub thiab txias deformation ntawm lub workpiece thiab txo cov zinc dross los ntawm hlau poob, cov chaw tsim khoom siv dav siv 450 ~ 470 ℃, 0.5 ~ 1.5min. Qee lub chaw tsim khoom siv qhov kub siab dua rau cov khoom loj loj thiab cov hlau castings, tab sis zam qhov kub thiab txias ntawm cov hlau tsis zoo. Txhawm rau txhim kho cov dej ntws ntawm cov dej kub dip plating ntawm qhov kub thiab txias, tiv thaiv cov txheej los ntawm tuab heev, thiab txhim kho cov tsos ntawm txheej, 0.01% mus rau 0.02% ntawm cov ntshiab txhuas feem ntau ntxiv. Aluminium yuav tsum tau ntxiv me me ntau zaus.
(6) ua tiav
Ua tiav cov haujlwm tom qab plating feem ntau yog tshem tawm cov zinc thiab zinc nodules, los ntawm kev co lossis phau ntawv.
(7) Passivation
Lub hom phiaj yog txhawm rau txhim kho cov kev tiv thaiv ntawm atmospheric corrosion ntawm qhov chaw ntawm lub workpiece, txo los yog ua kom ntev ntawm cov xim dawb, thiab ua kom lub ntsej muag zoo ntawm cov txheej. Lawv tag nrho cov passivated nrog chromate, xws li Na2Cr2O7 80 ~ 100g / L, sulfuric acid 3 ~ 4ml / L.
(8) Cua txias
Nws feem ntau yog dej-txias, tab sis qhov kub thiab txias yuav tsum tsis txhob qis dhau los tiv thaiv cov khoom ua haujlwm, tshwj xeeb tshaj yog cov casting, los ntawm kev tawg hauv matrix vim chilling thiab shrinking.
(9) Kev tshuaj xyuas
Cov tsos ntawm txheej yog ci, nthuav dav, tsis muaj sagging lossis wrinkles. Kev tshuaj xyuas thickness tuaj yeem siv txheej thickness ntsuas, txoj kev yog qhov yooj yim. Lub thickness ntawm txheej kuj tuaj yeem tau los ntawm kev hloov cov zinc adhesion. Lub zog sib txuas tuaj yeem khoov los ntawm kev khoov xovxwm, thiab cov qauv yuav tsum tau khoov ntawm 90-180 °, thiab yuav tsum tsis txhob muaj kab nrib pleb lossis tev ntawm txheej. Nws tseem tuaj yeem kuaj tau los ntawm kev ntaus nrog rauj hnyav.
2. Kub-dip galvanized txheej txheej txheej txheej txheej txheej txheej txheej txheej kub-dip galvanized txheej txheem yog txheej txheem ntawm kev tsim cov hlau-zinc alloy ntawm cov hlau matrix thiab cov txheej txheem zinc txheej sab nraud. Cov hlau-zinc alloy txheej yog tsim rau ntawm qhov chaw ntawm lub workpiece thaum kub-dip galvanizing. Cov hlau thiab cov zinc ntshiab txheej yog sib xyaw ua ke zoo, thiab cov txheej txheem tuaj yeem piav qhia yooj yim xws li: thaum cov hlau ua haujlwm tau muab tso rau hauv cov zinc molten, cov ntsiab lus ntawm zinc thiab alpha hlau (lub cev tseem ceeb) yog thawj zaug tsim ntawm lub interface. Qhov no yog ib qho siv lead ua los ntawm dissolving zinc atoms nyob rau hauv lub hauv paus hlau hlau nyob rau hauv ib tug khoom lub xeev. Ob lub atoms hlau yog fused, thiab qhov attraction ntawm cov atoms yog me me. Yog li ntawd, thaum zinc ncav cuag saturation nyob rau hauv cov khoom tov, ob lub ntsiab atoms ntawm zinc thiab hlau diffuse ib leeg, thiab zinc atoms uas tau diffused (los yog infiltrated) mus rau hauv cov hlau matrix migrate nyob rau hauv lub matrix lattice, thiab maj mam tsim ib tug alloy nrog. hlau, thiab diffuse Cov hlau thiab zinc nyob rau hauv lub molten zinc tsim ib qho intermetallic compound FeZn13, uas nkag mus rau hauv qab ntawm lub lauj kaub kub-dip galvanizing, uas yog hu ua zinc dross. Thaum lub workpiece raug tshem tawm los ntawm zinc immersion tov, ib tug ntshiab zinc txheej yog tsim rau saum npoo, uas yog ib tug hexagonal siv lead ua. Nws cov ntsiab lus hlau tsis ntau tshaj 0.003%.
Thib peb, kev tiv thaiv kev ua haujlwm ntawm cov txheej kub-dip galvanized Lub thickness ntawm electro-galvanized txheej feem ntau yog 5-15μm, thiab cov txheej kub-dip galvanized feem ntau yog siab tshaj 65μm, txawm tias siab li 100μm. Kub-dip galvanizing muaj kev tiv thaiv zoo, tuab txheej thiab tsis muaj organic inclusions. Raws li peb txhua tus paub, kev tiv thaiv huab cua corrosion mechanism ntawm zinc suav nrog kev tiv thaiv txhua yam thiab kev tiv thaiv electrochemical. Nyob rau hauv atmospheric corrosion tej yam kev mob, muaj kev tiv thaiv zaj duab xis ntawm ZnO, Zn (OH) 2 thiab zinc carbonate yooj yim nyob rau saum npoo ntawm zinc txheej, uas yuav ua rau kom lub corrosion ntawm zinc mus rau ib tug tej yam kev mob. Cov yeeb yaj kiab tiv thaiv (tseem hu ua dawb xeb) puas lawm thiab tsim ib zaj duab xis tshiab. Thaum cov zinc txheej raug puas tsuaj loj thiab cov hlau matrix muaj kev phom sij, zinc yuav tsim cov tshuaj tiv thaiv electrochemical rau cov matrix. Tus qauv peev xwm ntawm zinc yog -0.76V, thiab tus qauv peev xwm ntawm hlau yog -0.44V. Thaum zinc thiab hlau tsim microbattery, zinc yog yaj raws li anode. Nws yog tiv thaiv raws li ib tug cathode. Obviously, kub-dip galvanizing muaj zoo atmospheric corrosion tsis kam rau lub hauv paus hlau hlau tshaj electro-galvanizing.
Plaub, kev tsim tswj ntawm zinc tshauv thiab zinc slag thaum kub-dip galvanizing
Zinc tshauv thiab zinc dross tsis tsuas yog cuam tshuam rau qhov zoo ntawm zinc immersion txheej, tab sis kuj ua rau cov txheej yuav ntxhib thiab tsim zinc nodules. Ntxiv mus, tus nqi ntawm kub-dip galvanizing yog heev nce. Feem ntau, zinc noj yog 80-120kg ib 1 tuj workpiece. Yog hais tias zinc tshauv thiab dross hnyav, zinc noj yuav siab li 140-200kg. Kev tswj cov zinc carbon yog tsuas yog los tswj qhov kub thiab txias thiab txo cov scum uas tsim los ntawm oxidation ntawm zinc kua nto. Qee cov tuam txhab tsim hluav taws xob hauv tsev siv cov xuab zeb refractory, charcoal tshauv, thiab lwm yam. Cov teb chaws txawv teb chaws siv cov khoom siv ceramic los yog iav nrog cov thermal conductivity tsawg, siab melting point, tsis tshua muaj zog, thiab tsis muaj cov tshuaj tiv thaiv nrog zinc kua, uas tuaj yeem txo cov cua sov thiab tiv thaiv oxidation. Cov pob no yooj yim raug thawb tawm ntawm lub workpiece, thiab nws tsis nplaum rau lub workpiece. Kev mob tshwm sim. Rau kev tsim cov zinc dross hauv cov kua zinc, feem ntau yog zinc-hlau alloy nrog tsis tshua muaj fluidity tsim thaum cov ntsiab lus hlau yaj hauv zinc kua ntau tshaj qhov solubility ntawm qhov kub no. Cov ntsiab lus zinc hauv zinc dross tuaj yeem siab txog 95%, uas yog kub-dip galvanizing. Tus yuam sij rau tus nqi siab ntawm zinc. Nws tuaj yeem pom los ntawm qhov nkhaus ntawm cov hlau solubility hauv cov kua zinc uas muaj cov hlau yaj, uas yog, cov hlau poob, qhov sib txawv ntawm qhov kub thiab txias sib txawv. Nyob ib ncig ntawm 500 ° C, cov hlau poob nce nrawm nrog cua sov thiab tuav lub sijhawm, yuav luag nyob rau hauv kev sib raug zoo. Hauv qab lossis siab dua qhov ntau ntawm 480 ~ 510 ℃, cov hlau poob qis zuj zus nrog lub sijhawm. Yog li ntawd, tib neeg hu 480 ~ 510 ℃ lub malignant dissolution cheeb tsam. Nyob rau hauv qhov ntsuas kub no, zinc kua yuav corrode lub workpiece thiab zinc lauj kaub loj tshaj plaws. Cov hlau poob yuav nce ntxiv thaum qhov kub siab tshaj 560 ℃, thiab zinc yuav ua rau cov hlau matrix puas tsuaj thaum qhov kub siab tshaj 660 ℃. . Yog li, plating tam sim no tau ua nyob rau hauv ob thaj tsam ntawm 450-480 ° C thiab 520-560 ° C.
5. Kev tswj cov nqi ntawm zinc dross
Txhawm rau txo cov zinc dross, nws yog ib qho tsim nyog yuav tsum tau txo cov ntsiab lus hlau hauv zinc tov, uas yog pib nrog txo cov ntsiab lus ntawm cov hlau tawg:
⑴Plating thiab txuag hluav taws xob yuav tsum zam qhov chaw siab tshaj ntawm cov hlau tawg, uas yog, tsis txhob khiav ntawm 480 ~ 510 ℃.
⑵ Raws li qhov ua tau, cov khoom siv zinc lub lauj kaub yuav tsum tau welded nrog steel daim hlau nrog cov pa roj carbon thiab cov ntsiab lus tsis tshua muaj silicon. Cov ntsiab lus ntawm cov pa roj carbon ntau yuav ua kom lub zog ntawm cov hlau yias los ntawm cov kua zinc, thiab cov ntsiab lus ntawm silicon siab tuaj yeem txhawb kev xeb ntawm cov hlau los ntawm cov kua zinc. Tam sim no, 08F high-zoo carbon steel phaj feem ntau yog siv. Nws cov ntsiab lus carbon yog 0.087% (0.05% ~ 0.11%), silicon cov ntsiab lus yog ≤0.03%, thiab nws muaj cov ntsiab lus xws li npib tsib xee thiab chromium uas tuaj yeem tiv thaiv hlau los ntawm corroded. Tsis txhob siv cov pa roj carbon zoo tib yam, txwv tsis pub zinc noj yuav loj thiab lub neej ntawm zinc lauj kaub yuav luv. Nws kuj tau thov kom siv silicon carbide los ua zinc melting tank, txawm hais tias nws tuaj yeem daws cov hlau tsis tau, tab sis cov txheej txheem qauv kuj yog ib qho teeb meem.
⑶ Tshem tawm slag nquag. Qhov kub yog thawj zaug nce mus rau sab sauv ntawm cov txheej txheem kub kom cais cov zinc slag los ntawm cov kua zinc, thiab tom qab ntawd txo qis mus rau hauv qab txheej txheem kub, yog li ntawd cov zinc slag tso rau hauv qab ntawm lub tank thiab tom qab ntawd muab khaws cia nrog. ib diav. Cov khoom plated uas poob rau hauv cov kua zinc yuav tsum tau khaws cia rau lub sijhawm.
⑷ Nws yog ib qho tsim nyog los tiv thaiv cov hlau hauv tus neeg sawv cev plating los ntawm kev coj mus rau hauv lub tank zinc nrog lub workpiece. Cov xim liab-xim av muaj cov hlau uas muaj cov khoom sib xyaw ua ke yuav raug tsim thaum cov neeg sawv cev plating siv rau lub sijhawm, thiab nws yuav tsum tau lim tawm tsis tu ncua. Nws yog qhov zoo dua los tuav tus nqi pH ntawm tus neeg sawv cev plating nyob ib ncig ntawm 5.
⑸ Tsawg dua 0.01% txhuas nyob rau hauv cov tshuaj plating yuav ua rau kom lub cev qhuav dej. Tus nqi ntawm txhuas yuav tsis tsuas yog txhim kho lub fluidity ntawm zinc tov thiab ua kom lub brightness ntawm txheej, tab sis kuj pab txo cov zinc dross thiab zinc plua plav. Ib qho me me ntawm txhuas ntab ntawm cov kua dej yog qhov zoo los txo cov oxidation, thiab ntau dhau cuam tshuam rau qhov zoo ntawm cov txheej, ua rau qhov chaw tsis xws luag.
⑹ Cov cua kub thiab cua sov yuav tsum tsis sib xws los tiv thaiv kev tawg thiab cua sov hauv zos.