1. Dab tsi yog qhov kev txhais cov yam ntxwv ntawm cov tooj liab Nickel 70/30, thiab vim li cas lawv tseem ceeb rau kev ua haujlwm ntawm cov yeeb nkab luj tshib hauv kev xav tau kev pab cuam?
Copper Nickel 70/30, standardized as UNS C71500, yog ib qho alloy ntawm kwv yees li 70% Copper, 30% Nickel, nrog txhob txwm tshaj tawm, tswj kev ntxiv ntawm Hlau (~ 0.4-1.0%) thiab Manganese (~ 1.0% max). Nws yog ib qho alpha (ib-theem) cov khoom siv tshuaj alloy, uas yog lub hauv paus ntawm nws cov khoom.
Rau cov yeeb nkab luj tshib-ib qho khoom uas raug hloov pauv, muaj kev kub ntxhov, thiab muaj peev xwm cuam tshuam qhov cuam tshuam - cov yam ntxwv no yog qhov tseem ceeb:
Ib leeg-Phase Structure: Homogeneous alpha qauv muab tshwj xeeb tiv thaiv rau hauv zos corrosion, xws li pitting thiab crevice corrosion. Tsis muaj theem ob los ua qhov chaw pib rau galvanic nres hauv cov hlau nws tus kheej.
Hlau & Manganese Synergy: Cov no tsis yog impurities tab sis txhob txwm, tseem ceeb alloying ntsiab. Hlau, nyob rau hauv cov kev daws teeb meem, zoo heev txhim khu kev tiv thaiv rau impingement thiab yaig-corrosion- ib qho tseem ceeb tsis ua hauj lwm hom nyob rau hauv lub luj tshib qhov siab - ceev, turbulent kua hloov txoj kev. Nws pab tsim kom muaj zog, ua raws, thiab nws tus kheej- kho qhov chaw tiv thaiv oxide txheej (feem ntau Cu₂O). Manganese pab nyob rau hauv deoxidation thaum lub sij hawm melting thiab txhim kho kub workability.
Superior Strength & Ductility: Piv rau 90/10 CuNi los yog tooj liab ntshiab, 70/30 muaj zog tensile thiab yield zog ntau dua, tso cai rau tus tsim ntawm thinner, lighter phab ntsa luj tshib qhov twg tso cai los ntawm cov cai, los yog muab ib tug ntau dua kev ruaj ntseg yam. Nws cov ductility zoo heev ua rau cov txheej txheem txias txias (piv txwv li, mandrel dabtsi yog khoov) siv los tsim cov luj tshib seamless yam tsis muaj cracking.
Kev sib xyaw ua ke ntawm lub zog siab, ductility, thiab tenacious, tiv thaiv oxide txheej ua rau C71500 lub luj tshib tshwj xeeb rau kev tuav siab - nrawm, feem ntau abrasive, dej hiav txwv thiab lwm yam kev tawm tsam.
2. Nyob rau hauv kev tsim cov CuNi 70/30 yeeb nkab luj tshib, dab tsi yog cov txheej txheem tseem ceeb ntawm kev tsim khoom (seamless vs. welded), thiab qhov kev txiav txim siab zoo li cas yog qhov tseem ceeb rau txhua tus?
CuNi 70/30 lub luj tshib yog tsim los ntawm ob txoj hauv kev, txhua qhov muaj feem cuam tshuam rau kev ncaj ncees thiab tus nqi:
Seamless Luj Tshib (Mandrel Bent lossis Kub Tsim): Qhov no yog qhov hwm thiab feem ntau txoj hauv kev rau kev pabcuam tseem ceeb.
Txheej Txheem: Ib txoj kab ncaj nraim ntawm cov yeeb nkab CuNi 70/30 yog khoov dua ib lub mandrel siv lub vojvoog meej tuag. Rau qhov nruj dua radii lossis phab ntsa tuab, khoov tuaj yeem ua rau ntawm cov yeeb nkab rhuab (kub induction bending).
Qhov zoo: Qhov tsis muaj qhov vuam tshem tawm qhov kev pheej hmoo tseem ceeb rau kev xeb thiab kev ua haujlwm tsis zoo. Cov qauv nplej ntws tsis tu ncua nyob ib puag ncig khoov, tswj cov khoom siv kho tshuab thiab corrosion. Nws yog txoj hauv kev uas yuav tsum tau ua rau feem ntau ntawm naval, offshore, thiab siab - siab piping specifications.
Ua kom pom tseeb zoo: Kev tswj cov phab ntsa thinning ntawm cov extrados (sab nraum qhov khoov) thiab muaj peev xwm wrinkling ntawm intrados (sab hauv ntawm khoov) yog qhov tseem ceeb. Dimensional kam rau ua (tshwj xeeb tshaj yog ovality) thiab post- khoov tshav kub kho (kev ntxhov siab) yuav tsum tau tswj nruj me ntsis.
Welded luj tshib (Wrought los yog Fabricated): Cov no yog tsim los ntawm vuam ua ke ob los yog ntau tshaj forged los yog nias seem.
Txheej txheem: Feem ntau, lub forged "lub luj tshib tev" (ib ntu zoo li) yog kub - tsim thiab tom qab ntawd koom nrog ib lossis ntau qhov zoo tib yam tev ntawm Gas Tungsten Arc Vuam (GTAW / TIG) los ua ib lub luj tshib.
Daim ntaub ntawv: Ntau dua rau cov kab uas loj dua (piv txwv li, tshaj 24 ") qhov twg seamless dabtsi yog khoov yog impractical los yog txwv tsis pub kim.
Ua kom pom tseeb: Cov txheej txheem vuam tsim nyog (WPQ) thiab kev ua tiav yog txhua yam. Lub vuam yuav tsum siv qhov sib txuam lossis ntau dua - cov hlau nplaum (xws li ERCuNi). Kev nkag mus tag nrho, tsis muaj qhov tsis xws luag (porosity, tsis muaj fusion), thiab kev xa tawm kom zoo-weld kev kho cua sov kom rov qab kho corrosion nyob rau hauv tshav kub-Txoj kev cuam tshuam cheeb tsam (HAZ) tsis yog-negotiable. 100% radiographic kuaj (RT) yog tus qauv.
Rau cov dej ntsev tseem ceeb, tshuaj lom neeg, lossis kev siv sab nrauv, seamless mandrel -bent luj tshib tau dhau los teev tseg vim lawv qhov kev ntseeg tau.
3. Cov txheej txheem vuam tshwj xeeb thiab kev ceev faj dab tsi yog qhov tseem ceeb thaum txhim kho CuNi 70/30 lub luj tshib rau hauv cov kav dej?
Kev vuam zoo yog qhov tseem ceeb los tswj cov kev tiv thaiv corrosion ntawm tag nrho cov sib dhos. Cov txheej txheem yog nruj thiab sib txawv ntawm cov pa roj carbon lossis stainless hlau.
Filler Hlau Xaiv: Cov ntsiab lus qhia yog siv cov hlau muab tub lim nrog corrosion kuj sib npaug los yog ntau dua li cov hlau hauv paus. ERCuNi (AWS A5.6 classification) yog tus qauv xaiv, feem ntau nrog cov muaj pes tsawg leeg zoo ib yam li 70/30 lossis qee zaum 70/30 nrog ntau dua hlau / manganese. Tsis muaj qhov xwm txheej yuav tsum tau siv cov khoom siv rau 90/10 CuNi lossis tooj liab-silicon alloys, vim nws yuav tsim ob peb galvanic.
Kev Npaj & Ntxuav: Kev tu kom huv yog qhov tseem ceeb. Tag nrho cov oxides, roj, thiab cov khoom paug yuav tsum raug tshem tawm ntawm thaj chaw vuam siv cov txhuam hlau tsis muaj hlau (raug rau CuNi) thiab cov kuab tshuaj pom zoo. Oxides tuaj yeem ua rau tsis muaj fusion thiab porosity.
Shielding Gas: 100% Argon yog siv rau GTAW shielding thiab thaub qab. Kev tiv thaiv roj zoo yog xav tau ntawm ob lub hauv paus thiab lub ntsej muag ntawm cov vuam los tiv thaiv oxidation (uas zoo nkaus li dub sooty deposit). Trailing shields feem ntau pom zoo.
Ua ntej- Kub thiab Kub Kub: Ua ntej- cua sov feem ntau tsis tas yuav tsum tau rau cov ntu nyias tab sis yuav raug siv rau cov phab ntsa hnyav kom tsis txhob tawg. Qhov tseem ceeb, qhov kub ntawm qhov sib cuam tshuam yuav tsum tau tswj qis dua 150℃(300℃F). Kev siv hluav taws xob ntau dhau tuaj yeem ua rau cov qoob loo loj hlob hauv HAZ, txo lub zog thiab corrosion kuj.
Tom qab- Weld Heat Treatment (PWHT): Rau tag nrho cov welds me tshaj plaws, ib qho kev daws teeb meem tag nrho (qhov txias txias los ntawm 1050-}1150℃F) tau teev tseg kom yaj txhua theem nag lossis daus thiab rov ua dua ib theem qauv hauv HAZ. Qhov no yog ua raws li sai quenching los tiv thaiv embrittlement. Rau qee qhov kev siv, kev ntxhov siab ntawm ~ 500-600℃F yuav yog lwm txoj hauv kev.
4. Tshaj li cov dej hiav txwv, dab tsi yog lwm cov kev lag luam tseem ceeb rau CuNi 70/30 lub luj tshib, thiab cov cuab yeej twg ua rau lawv siv hauv txhua qhov?
Thaum lub nkoj tsim hluav taws xob yog nws qhov tseem ceeb, CuNi 70/30's tshwj xeeb cov cuab yeej profile ua rau nws muaj nuj nqis hauv ntau qhov chaw hnyav:
Offshore Oil & Gas Production & Processing: Lub luj tshib yog siv rau hauv cov dej tua hluav taws, tsim cov dej tuav, thiab cov tshuab ua kom txias. Ntawm no, tus tsav tsheb tseem ceeb yog tiv thaiv sulfide kev nyuaj siab tawg (SSC) thiab corrosion los ntawm qaub gases (H₂S thiab CO₂). CuNi 70/30 ua tau zoo dua li ntau cov hlau tsis muaj hlau nyob hauv qis -oxygen, sulfide- muaj ib puag ncig.
Tshuaj thiab Txheej Txheem Kev Lag Luam: Hauv kev tuav alkalis, ntsev, organic compounds, thiab txo cov kua qaub (xws li tsis yog - aerated hydrochloric thiab sulfuric acid). Nws tiv taus ntau yam pH thiab tsis yog - oxidizing media yog qhov tseem ceeb. Cov khoom siv los tiv thaiv-biofouling tseem yog qhov tseem ceeb hauv kev tiv thaiv microbial-induced corrosion (MIC) hauv cov txheej txheem ntws.
Desalination Nroj Tsuag (Multi-theem Flash & Thermal): Siv dav hauv cov cua sov rov qab thiab cov brine rhaub. Cov cuab yeej tseem ceeb ntawm no yog kev tiv thaiv rau ob qho tib si corrosion thiab scaling ntawm qhov kub siab (txog ~ 250℃/ 480℃F hauv qee ntu), tswj xyuas thermal efficiency.
Lub Hwj Chim Muaj Zog: Hauv cov tshuab tso dej tso cua sov, cov khoom siv condensers, thiab cov khoom siv cua txias (tshwj xeeb tshaj yog qhov dej khov lossis dej hiav txwv yog qhov ua kom txias). Kev sib xyaw ua ke ntawm thermal conductivity, corrosion fatigue resistance, thiab erosion resistance ua kom ntev -lub sij hawm kev cia siab nyob rau hauv thermal cycling tej yam kev mob.
Shipboard Sanitary & Ballast Systems: Siv nyob rau hauv piping qhov chaw tu cev thiab tiv thaiv cov kwj deg yog ib qho tseem ceeb, rov siv nws cov biofouling tsis kam thiab kav ntev.
5. Dab tsi yog qhov tseem ceeb rau kev ntsuam xyuas thaum xaiv thiab muab CuNi 70/30 lub luj tshib kom ua tau raws li cov cai thoob ntiaj teb cov kav dej thiab cov kev qhia tshwj xeeb?
Kev yuav cov khoom siv no rau kev cai- ua haujlwm raws li (xws li, ASME B31.3 Txheej Txheem Piping, B31.1 Fais Fab Piping, lossis cov qauv tub rog tshwj xeeb) yuav tsum muaj kev tshuaj xyuas nruj thiab cov ntaub ntawv.
Cov ntaub ntawv pov thawj: Daim Ntawv Pov Thawj Zeb Xeem (MTC) lossis Daim Ntawv Pov Thawj Ua Raws Li ASTM B466 / B467 (Txheej Txheem Specification rau Seamless and Welded Copper-}Nickel Pipe) yog lub hauv paus. Nws yuav tsum txheeb xyuas cov tshuaj muaj pes tsawg leeg thiab cov khoom siv kho tshuab. Rau cov haujlwm naval, MIL-C-15726 lossis DIN 17664 tej zaum yuav raug teev tseg.
Manufacturing Standard & Dimensions: Lub luj tshib yuav tsum ua raws li tus qauv seem xws li ASME B16.9 (Factory-Ua Wrought Buttwelding Fittings). Qhov no ua rau kom haum zoo- nce thiab phab ntsa thickness (schedule) txuam nrog cov yeeb nkab txuas. Tus neeg yuav khoom yuav tsum qhia cov hom (luv / ntev vojvoog, 45℃/ 90 degree), lub sijhawm, thiab qhov loj me.
Traceability & Marking: Txhua qhov haum yuav tsum tau cim mus tas li nrog cov khoom siv qib (xws li, C71500), cov chaw tsim khoom lub logo, qhov loj me, lub sijhawm, thiab cov xov tooj cua sov. Qhov no muab tag nrho traceability rov qab mus rau yaj thiab ua keeb kwm.
Tsis yog -Kev Tshawb Fawb Txog Kev Puas Tsuaj (NDE) Yuav Tsum Tau: Nyob ntawm chav kawm pabcuam, yuav tsum muaj kev sim ntxiv tshaj li tus qauv hydrotest. Qhov no tuaj yeem suav nrog:
Dye Penetrant Inspection (DPI): Rau kev kuaj pom qhov tsis xws luag ntawm cov vuam seams ntawm wrought luj tshib lossis lub hauv paus hlau.
Radiographic Testing (RT): Yuav tsum tau ua rau txhua qhov welds nyob rau hauv fabricated / wrought luj tshib thiab tej zaum yuav raug teev rau cov khoov cheeb tsam ntawm seamless lub luj tshib los xyuas cov workmanship flaws.
Kev txheeb xyuas cov ntaub ntawv zoo (PMI): Siv rab phom XRF ntawm - qhov chaw los xyuas qhov sib xyaw ua ke ntawm cov ntaub ntawv sib xws, ib kauj ruam tseem ceeb los tiv thaiv cov khoom sib tov-ups.
Kev Tiv Thaiv & Ntim: CuNi lub luj tshib yuav tsum tau muab ntxuav kom zoo, qhuav, thiab ntim khoom (feem ntau nrog lub kaus mom / ntsaws) txhawm rau tiv thaiv kev xeb, pitting, thiab kev puas tsuaj thaum lub sijhawm thauj mus los thiab khaws cia. Roj los yog roj-raws li preservatives feem ntau yog zam raws li lawv tuaj yeem cuam tshuam nrog kev vuam tom ntej.
