Dab tsi yog Nickel Ua hauv Vuam Hlau?

Nickel muaj cov khoom siv zoo heev, lub cev, thiab tshuaj lom neeg. Ntxiv cov ntsiab lus tsim nyog tuaj yeem txhim kho nws cov oxidation tsis kam, corrosion kuj, siab - kub lub zog, thiab qee yam khoom ntawm lub cev.

Kev huv huv ntawm qhov chaw ua haujlwm yog qhov tseem ceeb rau kev ua tiav vuam ntawm nickel-raws li corrosion- cov alloys resistant. Cov kab mob saum npoo av feem ntau muaj cov oxides saum npoo thiab cov khoom uas ua rau embrittlement.

Cov ntsiab lus uas tsim qis- melting- taw tes eutectics nrog Ni, xws li S, P, Pb, Sn, Zn, Bi, Sb, thiab As, yog cov khoom tsis zoo. Cov ntsiab lus tsis zoo no ua rau muaj kev nyiam kub kub tawg hauv npib tsib xee-raws li corrosion- cov alloys resistant.

Cov impurities no yuav tsum tau muab tshem tawm tag nrho ua ntej preheating lossis vuam.

1. Rhiav av thiab roj tuaj yeem raug tshem tawm los ntawm chav degreasing lossis nrog acetone thiab lwm yam kev daws teeb meem.

2. Cov xim thiab lwm yam khoom tsis huv hauv cov tshuaj degreasing tuaj yeem ntxuav nrog methylene chloride, alkaline ntxuav cov neeg ua haujlwm, lossis cov khoom siv hluavtaws tshwj xeeb. Cov cim cim feem ntau yog ntxuav nrog methanol.

3. Cov impurities nias rau hauv qhov chaw ua haujlwm tuaj yeem raug tshem tawm los ntawm kev sib tsoo, tua blasting, lossis ntxuav nrog cov tshuaj hydrochloric acid (10% ntawm ntim) ua raws li cov dej huv.

Vuam npib tsib xee-raws li corrosion- cov alloys resistant siv cov cua kub input txoj kev tuaj yeem muaj qhov tsis zoo. Ib qho℃ntawm annealing thiab grain loj hlob tshwm sim nyob rau hauv lub tshav kub- cuam tshuam cheeb tsam (HAZ).

Kev siv hluav taws xob siab tuaj yeem ua rau muaj kev sib cais ntau dhau, carbide nag lossis daus, lossis lwm yam teeb meem metallurgical tshwm sim. Qhov no tuaj yeem ua rau kub tawg lossis txo qhov kev tiv thaiv corrosion.

Lub grain loj ntawm lub hauv paus hlau yuav tsum tau txiav txim siab thaum xaiv vuam txoj kev thiab cov txheej txheem. Coarse-cov ntaub ntawv nplej muaj ntau carbides thiab intermetallic compounds nyob rau hauv lub grain ciam teb uas txhawb liquefaction cracking, yog li ua rau kom kub kub tawg.

1) Tsis zoo fluidity ntawm kua weld hlau

Lub vuam hlau tsis zoo fluidity thiab tsis yooj yim ntws mus rau ob sab ntawm vuam. Yog li ntawd, kom tau txais kev sib txuas zoo, qee zaum siv cov txheej txheem weaving. Txawm li cas los xij, qhov kev sib tw no yog ib qho me me oscillation, nrog rau qhov oscillation nrug tsis tshaj peb npaug ntawm txoj kab uas hla ntawm vuam pas nrig lossis hlau. Lub kaum sab xis ntawm qhov sib koom ua ke kuj loj dua.

2) Pem hauv ntej weld nkag

Qhov no kuj yog ib qho tseem ceeb ntawm cov npib tsib xee -raws li corrosion- resistant alloys. Ib yam li ntawd, nce qhov vuam tam sim no tsis nce qhov tob tob. Raws li tau hais los saum toj no, ntau dhau tam sim no cuam tshuam rau vuam, ua rau tawg thiab porosity.

3) Preheating thiab post -weld heat treatment

Nickel-raws li corrosion-cov alloys resistant feem ntau tsis tas yuav preheating ua ntej vuam. Txawm li cas los xij, thaum lub hauv paus hlau kub qis dua 15 degree, thaj tsam li ntawm 250-300mm ntawm ob sab ntawm kev sib koom tes yuav tsum tau rhuab mus rau 15-20℃kom tsis txhob ya raws. Kev kho cua sov tom qab vuam feem ntau tsis pom zoo.

1) Beveling yuav tsum zoo dua yog ua los ntawm kev siv tshuab. Yog tias siv cov plasma txiav, cov txheej txheem yuav tsum tau ntxuav;

2) Lub beveling yuav tsum tau ua nrog lub kaum sab xis loj thiab me me blunt ntug, thiab yuav tsum ua raws li tus qauv tsim thiab cov lus qhia ua haujlwm;

3) Tom qab beveling, ib qho kev kuaj pom yuav tsum tau ua. Lub bevel nto yuav tsum tsis muaj kab nrib pleb, delamination, thiab lwm yam tsis xws luag;

4) Yog tias tus qauv tsim yuav tsum tsis yog - kev sim ua kom puas tsuaj ntawm bevel nto, nws yuav tsum tau ua raws li cov qauv tsim. Yog tias tsis muaj cov qauv tsim tshwj xeeb, rau cov kav dej cam khwb cia, cov kav dej thiab cov fittings siv rau cov xov xwm uas muaj kev phom sij heev, thiab cov kav dej lossis cov khoom siv nrog cov qauv tsim siab sib npaug los yog ntau dua 10 MPa, lub bevel yuav tsum raug rau kev sim nkag mus. Txhua yam tsis xws luag yuav tsum tau muab tshem tawm tam sim.

Ua ntej sib dhos, roj stains, xeb, thiab lwm yam, yuav tsum tau muab tshem tawm ntawm lub bevel thiab tsis pub dhau 20 hli ntawm ob sab kom txog rau thaum nws yog xim hlau luster. Qhov sib thooj ntawm qhov chaw yuav tsum tau ntxuav nrog cov organic hnyav ua ntej vuam; Tom qab cov kuab tshuaj evaporates, ib qho tshuaj tiv thaiv - spatter txheej yuav tsum tau siv nyob rau hauv 100mm ntawm ob sab ntawm lub bevel.

1) Thaum vuam, siv txoj kev vuam uas tsis tshua muaj tam sim no, me me oscillation, thiab tsis tshua muaj cua sov input;

2) Thaum siv TIG vuam, sab hauv ntawm cov yeeb nkab yuav tsum tau purged nrog argon roj, nrog argon purity tsis tsawg tshaj li 99.99%. Thaum lub hauv paus hla kev vuam, tuav ib lub qhov me me nrog txoj kab uas hla ntawm 2mm-3mm ntawm ntug ntawm lub pas dej ua ke, thiab cov vuam hlau yuav tsum raug xa mus rau lub pas dej weld hauv ib lub tee dej;

3) Thaum ua tiav phau ntawv arc vuam rau txhaws thiab capping, thov cov hmoov av nplaum rau hauv cov hlau hauv ib thaj tsam ntawm tsawg kawg yog 100mm ntawm ob sab ntawm qhov zawj kom tsis txhob vuam spatter los ntawm kev puas tsuaj rau lub hauv paus hlau;

4) Ua tib zoo ntxuav cov interlayers thiab nto siv lub kaum sab xis grinder lossis stainless hlau hlau txhuam. Sib tsoo thiab txiav yuav tsum siv cov corundum sib tsoo dawb, thiab yuav tsum tsis txhob tov nrog carbon steel;

5) Cov kav dej thiab cov khoom siv yuav tsum tau muab tso rau hauv cov roj hmab lossis cov ntaub qhwv asbestos thiab yuav tsum tsis txhob sib xyaw nrog cov pa roj carbon steel;

6) Yog tias muaj kev sib tshooj ua haujlwm nyob rau ntawm - qhov chaw teeb tsa, npog thaj chaw muaj feem cuam tshuam ntawm cov kav dej nrog cov ntaub asbestos;

7) Rau cov kav dej uas muaj cov phab ntsa loj, cov welding symmetrical yuav tsum tau siv los ua kom tsis txhob vuam deformation;

8) Lub qhov (socket) vuam yuav tsum tau ua tiav nyob rau hauv ob txoj kev;

9) Tom qab welding tiav lawm, ntxuav lub weld nto tam sim ntawd thiab ua ib qho kev soj ntsuam ntawm lub vuam. Tom qab ua tau raws li cov qauv zoo, sau tus welder tus lej ntawm cov yeeb nkab 20mm-50mm deb ntawm qhov vuam siv cov txheej uas tsis muaj zinc, sulfur, lossis lwm yam khoom.

1) Vim tias qhov tob tob tob tob thiab qhov dej tsis zoo ntawm cov npib tsib xee molten-raws li corrosion- cov alloys resistant, vuam tsis yuav tsum nruj me ntsis tswj thaum lub vuam txheej txheem. Nickel-raws li corrosion-tiv taus hlau electrodes feem ntau siv ncaj qha tam sim no, nrog cov electrode txuas nrog lub davhlau ya nyob twg zoo.

2) Txhua hom thiab qhov loj ntawm electrode muaj qhov zoo tshaj plaws tam sim no. Lub vuam tam sim no rau ib qho kev sib koom tes yuav tsum xav txog yam xws li lub hauv paus hlau thickness, vuam txoj hauj lwm, hom sib koom tes, thiab clamping rigidity.

3) Molten npib tsib xee-raws li corrosion- cov hlau tsis muaj dej tsis zoo. Txhawm rau tiv thaiv qhov tsis xws luag xws li tsis muaj fusion thiab porosity, nws yog qhov yuav tsum tau ua kom tsim nyog oscillate electrode thaum vuam.

4) Thaum tawg lub arc, me ntsis txo qhov arc qhov siab thiab ua kom lub vuam ceev kom txo qhov loj ntawm lub pas dej weld. Qhov no tuaj yeem txo qhov crater cracking. Thaum re- tawm tsam lub arc ntawm qhov sib koom ua ke, rov qab arc striking thev naus laus zis yuav tsum tau siv los pab txhawb kev hloov kho ntawm cov vuam smoothness ntawm qhov sib koom tes thiab pab txo qhov tshwm sim ntawm porosity.