Q1: Hauv cov dej num uas tsawg yog Q345d steel yeeb nkab Irreplaceable?
Q345d steel yeeb nkas ua lub luag haujlwm tseem ceeb hauv cov roj thiab roj pipeline cov phiaj xwm hauv cheeb tsam Arctic thiab tuaj yeem tiv taus ntau qhov chaw hauv qab -40. Cov txheej txheem kev txhawb nqa ntawm Lng tau txais cov chaw tau txais Q345D steel kav vim tias nws tseem tuaj yeem tswj cov tawv xim zoo hauv qab kev sib sib zog nqus. Q345d steel kav yog thawj qhov kev xaiv rau cov chaw tsim khoom loj ntawm cov chaw muaj kev nyab xeeb kom ntseeg tau qhov kev tsim kho hauv lub caij ntuj no. Cua fais fab yees yuav tsum siv Q345D cov ntaub ntawv nyob rau thaj tsam txias sab qaum teb kom tawm tsam qhov cuam tshuam ntawm cov cua tsis tshua muaj cua. Cov qauv steel hlau pob txha pob txha thiab cov khoom ncaws pob ua si ntau zaus kuj siv Q345D steel kav kom tau raws li cov kabmob hlau-cov kabmob nyob rau hauv qis ntsuas chaw ib puag ncig.
Q2: Vim li cas yuav tsum Q345d Steel kav yuav siv rau lub plhaub sab nraud ntawm lng cia tso tsheb hlau luam?
Lub plhaub sab nraud ntawm LNG cia tso tsheb hlau luam yuav tau los tiv thaiv huab qis ntawm Q345D Steel kav phim zoo nrog 9% npib tsib xee lub tank. Nws zoo heev qis-kub cuam tshuam todness (-20℃cuam tshuam lub zog loj dua los yog sib npaug ntawm 34j) tuaj yeem tiv thaiv qis qis-kub brittle tawg. Cov kab mob sulfur thiab phosphorus qis thiab phosphorus cov ntsiab lus ntawm Q345D steel yeeb (tsawg dua lossis sib npaug ntawm 0.030%) txo qhov kev pheej hmoo ntawm kev tawg. Lub plhaub qauv yuav tsum tau qhib cov cua siab thiab cov seismic thauj khoom, thiab lub zog siab ntawm Q345d (tawm los ntawm 345MPA) muab kev tiv thaiv zoo dua. Cov chaw kho saum npoo siv SA2.5 qib sandblasting + inorganic zinc txheej kom ntseeg tau ntev lub sij hawm tiv thaiv corrosion.
Q3: Cov khoom tshwj xeeb yog dab tsi rau Q345D steel yeeb nkab hauv cov cua tshuab ntauwd tsim?
Q345d steel phaj rau cov cua turbine ntauwd yuav tsum muaj Z-kev taw qhia kev ua tau zoo (Z15, hla kev sib luag ntau dua lossis sib npaug nrog 35% los tiv thaiv lamellar. Qhov kub yuav tsum tau tswj hwm ntau dua lossis sib npaug rau 100℃thaum lub sijhawm yob kom tsis txhob cov khoom embrittlement tshwm sim los ntawm kev kub tsawg. Tom qab vuam ntev weld, kev nyuaj siab kev kho cua sov kho cua sov (580℃× 2h yuav tsum tau nqa tawm mus tshem tawm cov kev ntxhov siab vuam. Cov Flange Qe Qab Annular Seam yuav tsum tau 100% tofd + siv tshuaj ntsuam kom ntseeg tau Vuam zoo. Cov txheej txheem los tiv thaiv corrosion siv kev sib txuas ntawm Epoxy Primer (120μm) + Polyurethane Topcoat (80μm) los xyuas kom muaj lub neej tiv thaiv ntau tshaj 20 xyoo.
Q4: Cov teeb meem twg yuav tsum tau them nyiaj rau thaum siv Q345D steel kav rau cov hlab kub tsawg?
Thaum lub tuab tshaj 16mm, nws yuav tsum yog preheated rau 120 ~ 150℃ua ntej vuam los tiv thaiv cov kab nrib pleb. Cov ntaub ntawv vuam yuav tsum siv cov ntaub ntawv vuam siv cov roj av ultrasonic tsawg dua lossis muaj sib npaug nrog 5ml / 100g) kom txo qis kev pheej hmoo ntawm hydrogen-inducts nrib pleb. Lub caj pas Thickness ntawm Fillet Weld yuav tsum tsis pub tsawg tshaj 0.7 zaug lub thickness ntawm thickness ntawm thinner ntawm thinner ntawm thinner ntawm thinner ntawm thinner phaj kom ntseeg tau tias lub zog sib txuas. Thaum lub ambient kub yog qis dua -5 degree, ib qho kev thaiv lub rwb thaiv tsev yuav tsum tau ua rau kev ua haujlwm vuam. Dehydogenation kev kho (250℃× 1h) yuav tsum tau nqa tawm hauv 24 teev tom qab vuam los tshem tawm hydrogen nyob rau hauv weld.
Q5: Vim li cas yog Q345d steel yeeb nkab nyiam rau dej kav dej hauv thaj chaw txias heev?
Q345D Cov kav dej steel tuaj yeem tiv taus los ntawm te rowe kev ntxhov siab, kom ntseeg tau tias cov kav dej tsis muaj kev ntxhov siab, kom ntseeg tau tias cov kav dej tseem tuaj yeem ua haujlwm kom muaj kev nyab xeeb hauv qab qhov taw tes khov. Furied Pipelines xav tau cov khoom siv hluav taws xob ntawm -30℃yuav loj dua los yog sib npaug rau 27J (GB / T 9711 POSL2 txujci). Sab hauv phab ntsa yog coated nrog epoxy cob (qhuav zaj duab xis tuab ntau dua los yog sib npaug rau kev kho kom xeb los ntawm dej khov. Lub luj tshib yuav tsum tau ua siv cov annealing kub (rhuab mus rau 950 degree), thiab ib txwm muaj kev kho mob hauv zos yog qhov yuav tsum tau tom qab txias. Qhov kev txav ntawm cov av khov av yuav tsum tau txiav txim siab thaum tsim cov raj xa dej, thiab ib hom kev sib txuas tau yooj yim yuav tsum tau them rau kev hloov pauv.
