API 5L X65 Khoom siv yog dab tsi?
API 5L X65 yog cov pa roj carbon -manganese pipeline steel nrog microalloying ntxiv, txhais nyob rau hauv API Specification 5L / ISO 3183 nyob rau hauv metric designation L450. Tus lej lej hais txog qhov tsawg kawg nkaus tawm lub zog: 65,000 psi nyob rau hauv lub imperial system, sib npaug rau 450 MPa. Nws yog ib qho ntawm cov kab yeeb nkab siv ntau tshaj plaws vim nws muab lub zog siab - rau- qhov hnyav piv yam tsis muaj kev nplua weldability uas los nrog cov qib siab zog, thiab vim nws tuaj yeem tsim kev lag luam hauv seamless, siab - zaus welded thiab submerged arc welded cov ntaub ntawv.
X65 khoom yog muab nyob rau hauv ob theem khoom specification. PSL 1 txhais cov ntsiab lus tseem ceeb ntawm cov tshuaj lom neeg thiab cov khoom siv, thaum PSL 2 ntxiv qhov yuav tsum tau muaj cov pa roj carbon sib npaug sib npaug, yuav tsum tau ntsuas qhov ntsuas qhov hnyav thiab nruj dua txwv ntawm chemistry thiab tshuaj xyuas. Hauv PSL 2 tus qauv lees paub ntau yam kev xa khoom, txheeb xyuas los ntawm tsab ntawv txuas ntxiv, uas piav qhia seb cov khoom kawg tau txais li cas.
Chemical Composition thiab Microalloying
X65 tsis yog ib qho kev sib xyaw ruaj khov. Tus txheej txheem teeb tsa qhov siab tshaj plaws rau cov ntsiab lus tseem ceeb thiab tawm qhov sib npaug rau tus tsim steel, muab cov khoom siv kho tshuab thiab cov pa roj carbon sib npaug. Cov kev txwv rau qhov siab dua - lub zog PSL 2 cov xwm txheej yog carbon 0.18 % max, silicon 0.45 % max, manganese 1.60 % max, phosphorus 0.025 % max thiab sulfur 0.015 % max, nrog rau cov pa roj carbon ntau tshaj 0.42 % CE ntawm qhov sib npaug ntawm CE 0.25% siab tshaj ntawm CEpcm.
| Element | Muaj nuj nqi hauv cov khoom |
|---|---|
| Carbon thiab manganese | Muab lub hauv paus lub zog ntawm cov hlau, khaws cia tsawg txaus kom khaws toughness thiab weldability |
| Niobium, vanadium, titanium | Microalloying ntxiv uas ua kom zoo dua cov nplej thiab nce lub zog los ntawm nag lossis daus, feem ntau nrog kev txwv ntawm 0.15% siab tshaj |
| Phosphorus thiab sulfur | Txwv rau qib qis vim tias lawv txo cov tawv nqaij thiab tiv thaiv kev tawg |
| Carbon sib npaug | Kev ntsuas qhov ntsuas ntawm weldability, tswj hardenability ntawm tshav kub- cuam tshuam cheeb tsam |
Vim tias cov pa sib npaug ntau dua li cov pa roj carbon ib leeg tswj kev pheej hmoo tawg, X65 cua sov tuaj yeem ua tau zoo ntawm kev txwv chemistry thiab tseem tsis tsim nyog rau cov txheej txheem vuam yog tias cov pa sib npaug zaum saum qhov ntau.
Mechanical Properties
| Khoom | PSL 1 | PSL 2 |
|---|---|---|
| Yield zog, MPa | 450 min | 450-570 Nws |
| Tensile zog, MPa | 535 nqi | 535a760 ua |
| Yield rau tensile ratio | Tsis tau teev tseg | Txwv rau strain-raws li daim ntawv thov tsim |
| Kev sim cuam tshuam | Tsis xav tau | Yuav tsum tau, nrog rau qhov ntsuas kub pom zoo ntawm kev txiav txim |
Elongation yog xam es tsis kho, siv cov mis muab rau hauv API 5L: Af=1940 x A^0.2 / U^0.9 rau SI units, qhov twg A yog tus ntoo khaub lig siv tau -sectional cheeb tsam ntawm tensile specimen thiab U yog qhov tsawg kawg nkaus tensile zog. Kev cuam tshuam lub zog xav tau rau PSL 2 yeeb nkab tau qhia tias lub zog nqus hauv joules ntawm qhov ntsuas kub ntsuas rau lub hauv paus hlau, vuam thiab cua sov- cuam tshuam thaj tsam sib cais.
Kev xa khoom thiab kev kho cua sov
Raws li - dov, siv rau qib qis zog uas qhov kev sib xyaw ib leeg muab cov khoom xav tau
Normalised, muab cov ferrite sib xws -pearlite qauv nrog zoo toughness
Normalized dov, tswj dov xyaum ua kom tsis txhob muaj kev sib cais normalizing
Thermomechanically dov, feem ntau txoj kev rau X65 vim hais tias nws sib txuas lub zog siab nrog cov nplej loj thiab zoo heev toughness
quenched thiab tempered, siv qhov kev sib zog nruj dua lossis txhim kho qis -kub toughness yuav tsum tau
Thermomechanically dov cov ntaub ntawv raug txiav txim nrog lub sijhawm teev siab tshaj plaws dov kub, thiab cov cua kub tom qab tshaj qhov txwv, xws li kub sib sau los yog kev ntxhov siab, tuaj yeem rhuav tshem cov khoom sib npaug ua tiav hauv lub zeb. Qhov twg tom qab-weld kev kho cua sov yog npaj, nws yuav tsum tsim nyog rau cov khoom siv yeeb nkab ua ntej pib tsim khoom.
Vuam thiab Fabrication Guide
Field welding ntawm X65 kab yeeb nkab feem ntau yog ua tiav nrog cov txheej txheem tsim nyog npog cov yeeb nkab qib, phab ntsa thickness, consumable thiab txoj hauj lwm. Tsawg-hydrogen consumables thiab tswj preheat yog siv rau hnyav phab ntsa thicknesses thiab high carbon sib npaug heats, thaum hardness txwv yog siv rau vuam thiab tshav kub- thaj tsam cuam tshuam thaum kab yog npaj rau qaub kev pab raws li ISO 15156 / NACE MR0175. Qhov twg cov raj xa dej tau tsim los rau kev lim dej-raws li cov xwm txheej, xws li hauv cheeb tsam seismic lossis permafrost, cov txheej txheem girth weld yuav tsum tsim nyog rau lub peev xwm tensile es tsis yog lub zog ib leeg.
Tej kev siv
X65 kab yeeb nkab yog siv rau siab - cov pa roj thiab cov roj xa hluav taws xob, cov xaim hluav taws xob sab nrauv thiab cov risers, cov tshuab sib sau ua ke, cov dej txhaj tshuaj thiab cov kav dej xa mus, thiab cov qauv tubular xav tau kev ntsuas siab. Lub zog siab dua X60 txo cov phab ntsa tuab thiab tag nrho cov tonnage, thaum qib tseem yooj yim dua rau vuam dua X80 hauv thaj chaw, uas yog vim li cas nws tseem yog qhov kev xaiv siv rau ntau qhov kev sib kis.
FAQ
Q: X65 txhais li cas hauv API 5L?
X65 yog qhov kev xaiv qib imperial rau kab yeeb nkab nrog qhov ntsuas qhov siab tshaj plaws ntawm 65,000 psi, sib npaug rau 450 MPa. Tus qauv metric hauv tib tus qauv yog L450.
Q: Dab tsi yog qhov tawm los thiab tensile lub zog ntawm X65 yeeb nkab?
Qhov tshwj xeeb tshaj tawm lub zog yog 450 MPa thiab lub zog tensile tsawg kawg nkaus yog 535 MPa. PSL 2 yeeb nkab kuj teem ib qho kev txwv siab tshaj ntawm 570 MPa thiab lub siab tensile txwv ntawm 760 MPa.
Q: Qhov txawv ntawm X65 PSL 1 thiab PSL 2 yog dab tsi?
PSL 1 suav nrog cov txheej txheem tshuaj lom neeg thiab kev siv tshuab. PSL 2 ntxiv cov pa roj carbon sib npaug, qhov yuav tsum tau kuaj xyuas cov hlau hauv paus, vuam thiab cua sov- thaj tsam cuam tshuam, thiab nruj dua chemistry thiab tshuaj xyuas.
Q: Vim li cas microalloying siv hauv X65 steel?
Ntxiv me me ntawm niobium, vanadium thiab titanium refine lub grain qauv thiab tsa lub zog, yog li cov khoom yuav tsum tau tsis muaj carbon siab, uas ua rau cov khoom weldable thiab tawv.
Q: Dab tsi yog qhov kev xa khoom tom qab xws li M lossis Q txhais tau li cas?
Lub ntsiab lus txheeb xyuas seb cov khoom kawg tau ua tiav li cas, piv txwv li thermomechanical dov (M) lossis quenching thiab tempering (Q). Lub ntsiab lus yuav tsum tau hais thaum xaj vim tias nws cuam tshuam rau qhov toughness, lub zog ntau thiab kev siv vuam.
Q: Yuav ua li cas elongation teev rau X65 yeeb nkab?
Nws yog xam nrog cov mis Af=1940 x A^0.2 / U^0.9 hauv SI units, siv tus ntoo khaub lig-sectional cheeb tsam ntawm lub xeem daim thiab qhov tsawg kawg nkaus tensile lub zog, es tsis yog ib tug taag nqi.
