Siv Q690E (lub quenched & tempered ultra- siab- lub zog steel nrog Ntau dua lossis sib npaug ntawm 690 MPa yield zog thiab -40℃toughness) rau cua turbine yees sawv cev rau pem hauv ntej hauv kev tsim, ua kom siab dua, sib zog yees rau ntau dua lub zog ntes. Txawm li cas los xij, daim ntawv thov no cuam tshuam cov hlau mus rau qhov nyuaj, siab - voj voog, qhov sib txawv-amplitude qaug zog loading los ntawm cua, lub ntiajteb txawj nqus, thiab rotor dynamics. Txhim khu kev qaug zog yog qhov tseem ceeb rau lub neej tsim 20-25 xyoo.
Lub tswv yim yuav tsum yog holistic, tsom rau kev tsim, tsim, thiab tom qab- kev kho mob los tiv thaiv cov khoom siv hauv paus ntawm cov khoom. Ntawm no yog ib tug systematic mus kom ze:
1. Tsim Theem: Lub hauv paus ntawm Lub Neej Ntshai
Kev qaug zog lub neej yog dhau los txiav txim siab ntawm daim duab kos duab. Lub hom phiaj yog kom tshem tawm cov kev ntxhov siab concentrators.
Kev faib tawm nthuav dav: Tsim txhua qhov kev sib txuas thiab kev hloov pauv mus rau cov ncauj lus kom ntxaws txog kev qaug zog siab tshaj plaws (piv txwv li, Qeb 140 lossis siab dua ib tus qauv zoo li EN 1993-1-9 lossis sib npaug). Qhov no txhais tau tias:
Siv tag nrho Penetration Butt Welds: Rau tag nrho cov thawj longitudinal thiab circumferential welds. Tshem tawm cov tuav tuav thiab zom cov hauv paus weld thiab lub hau yaug nrog lub hauv paus hlau, kom ntseeg tau tias qhov zoo nkauj sab hauv thiab sab nrauv.
Tsis txhob sib txuas ntawm Flanges: Tsis txhob vuam nqa cov hlua, hlua hlua, lossis lwm yam txuas ncaj qha mus rau phab ntsa ntauwd (tshwj xeeb tshaj yog nyob rau sab qis). Siv cov kev daws teeb meem clamped lossis bolted hloov.
Generous Radii: Txhua qhov kev hloov pauv hauv ntu (piv txwv li, ntawm qhov rooj qhib, kev hloov pauv) yuav tsum muaj lub vojvoog loj, du. Tsis txhob muaj cov ntse ntse.
Flange-rau-Shell Connections: Tsim nrog kev hloov pauv. Nyiam cov kev hloov pauv conical tshaj qhov hloov pauv sai.
2. Fabrication & Vuam: Cov txheej txheem tseem ceeb
Imperfections qhia ntawm no yog thawj pib ntawm kev qaug zog tawg.
Fit-Up & Alignment: Perfect fit-up yog qhov yuav tsum tau ua. Kev tsis sib haum (hi-lo) yuav tsum tau txo qis (< 10% of plate thickness). Misalignment creates secondary bending stresses.
High -Cov txheej txheem vuam zoo:
Txheej Txheem: Siv cov khoom siv hluav taws xob / tshuab hluav taws xob Submerged Arc Vuam (SAW) lossis Gas Hlau Arc Vuam (GMAW) kom muaj kev sib luag zoo dua.
Tsawg-Hydrogen Xyaum: Yuav tsum tau tiv thaiv hydrogen-induced txias cracking (HICC). Siv cov khoom ci qis qis -hydrogen electrodes/flux, ua ntej- cua sov (feem ntau 100-150℃rau Q690E), thiab tswj qhov kub ntawm qhov sib txawv.
Weld Profile: Tsim du, convex weld profiles nrog lub ntsej muag maj mam hloov lub kaum sab xis (tsim rau ~ 30 degree). Undercut yog txwv tsis pub.
Tshaj tawm -Kev kho cua sov (PWHT): Rau tuab- ntu Q690E cov yees (Ntau dua lossis sib npaug li 50 hli), PWHT tau pom zoo kom txo qis qhov seem ntawm cov vuam kev ntxhov siab, uas tuaj yeem ua rau feem ntau ntawm lub voj voog kev ntxhov siab.
Cov Khoom Siv Zoo: Qhia Q690E nrog siab Z- kev taw qhia (los ntawm -} tuab) cov khoom (Z25 lossis Z35) los tiv thaiv lamellar tearing hauv kev txwv T- cov pob qij txha lossis cov phaj tuab.
3. Tshaj tawm -Kev kho Weld (PWT) - Qhov Kev Hloov Pauv rau Q690E
Qhov no yog txoj hauv kev ncaj ncees thiab muaj zog tshaj plaws los txhim kho lub zog qaug zog ntawm cov ntsiab lus welded, feem ntau txhim kho cov ncauj lus nthuav dav los ntawm 1-2 chav kawm.
Burr Sib Tsoo / Weld Toe Sib Tsoo: Sib tsoo cov ntiv taw ntiv taw mus rau qhov profile du, tshem tawm cov ntse ntse thiab cov slag hauv qab. Qhov no siv tau zoo thiab siv dav.
TIG Hnav khaub ncaws (Remelting): Siv lub teeb TIG los tshem cov ntiv taw ntiv taw, ua kom lub ntsej muag zoo nkauj thiab ua kom zoo nkauj microstructure. Qhov no kuj pab tab sis yuav tsum tau tswj kom meej.
Siab-Kev Kho Mob Zaus (HiFIT) / Ultrasonic Impact Treatment (UIT): Qhov no yog tus qauv kub rau cov ntawv thov tseem ceeb.
Txheej Txheem: Siv cov koob ultrasonic rau rauj cov ntiv taw vuam, inducing:
Cov txiaj ntsig Compressive Residual Stresses: Qhov no yog qhov tseem ceeb. Compressive stresses counteract lub tensile kev pab cuam loads, dramatically qeeb pib tawg.
Geometry Txhim Kho: Smoothen tus ntiv taw.
Microstructure Refinement: Ua haujlwm- ua kom tawv nqaij.
Cov nyhuv: tuaj yeem txhim kho lub neej qaug zog los ntawm qhov ua tau zoo ntawm 3 txog 10. Nws yog qhov tshwj xeeb tshaj yog rau siab -lub zog steels xws li Q690E vim tias lawv tuaj yeem txhawb nqa kev ntxhov siab ntau dua.
4. Kev tiv thaiv ib puag ncig
Kev Tiv Thaiv Kev Tiv Thaiv: Kev qaug zog hauv huab cua (Fatigue ~ Cua) yog siab dua nyob rau hauv ib puag ncig corrosive (Fatigue ~ Corrosion). Lub txheej txheej zoo yog qhov tseem ceeb:
Sab hauv: Epoxy txheej.
Sab nrauv: Ntau- txheej txheej txheej (epoxy + polyurethane) haum rau huab cua hauv hiav txwv / sab ntug dej hiav txwv hnyav.
Tsis txhob Fretting & Hnav: Ntawm bolted flange kev sib txuas, xyuas kom zoo bolt preload thiab siv cov coatings/pads tiv thaiv los tiv thaiv micro- txav thiab fretting qaug zog.
5. Advanced Manufacturing & Monitoring
Precision Txiav: Siv laser lossis plasma txiav nrog kev tswj cov cua sov kom tsis txhob tsim ib qho nyuaj, tawg -rhiab kub- cuam tshuam cheeb tsam ntawm cov npoo.
Kev Saib Xyuas Kev Noj Qab Haus Huv (SHM): Nruab cov ntsuas ntsuas ntsuas thiab ntsuas lub suab nrov ntawm cov ntsiab lus tseem ceeb (piv txwv li, ntu qis tshaj plaws, qhov rooj qhov rooj) txhawm rau saib xyuas qhov kev ntxhov siab tiag tiag thiab kuaj xyuas qhov pib tawg thaum ntxov.
Daim ntawv thov -Kev txiav txim siab tshwj xeeb rau Cua Turbine Ntauwd:
| Cov ntsiab lus tseem ceeb | Fatigue Risk | Txhim kho lub tswv yim |
|---|---|---|
| Longitudinal & Circumferential Welds | Crack pib ntawm weld ntiv taw / hauv paus. | Kev nkag mus tag nrho, av yaug + UIT siv rau txhua tus ntiv taw kab. |
| Qhov rooj / qhov rais qhib | High stress concentration ntawm cov ces kaum. | Elliptical qhib nrog lub kaum sab xis loj, ntxiv dag zog nrog ob daim hlau welded nrog kev nkag mus rau tag nrho thiab UIT. |
| Flange Nplhaib Connections (Bolted) | Khoov kev nyuaj siab, muaj peev xwm rau fretting. | Precision machining ntawm qhov chaw tiv tauj, siab - lub zog preloaded bolts, kev sib txhuam- txhim kho cov txheej txheem (xws li, thermally sprayed Al). |
| Internal / External Attachments | Local stress raisers. | Zam txhob yog ua tau. Siv nruam weld profiles yog xav tau, ua raws li ntiv taw sib tsoo. |
| Base Ring rau Weld | Complex multi-axial stress. | Tag nrho kev nkag mus vuam nrog lub vojvoog hloov pauv, yuav tsum tau PWHT rau cov ntu tuab, ua raws li UIT. |
Qhov tseem ceeb "DO NOTs" rau Q690E:
Tsis txhob cia tej undercut nyob twj ywm. Nws yog ib tug haib crack starter.
Tsis txhob hla PWHT rau cov phaj tuab; residual stress yog ib qho tseem ceeb ntawm kev qaug zog.
Tsis txhob xav tias muaj zog dua steel muaj zog dua qaug zog. Kev qaug zog txwv (kev txwv kev ua siab ntev) feem ntau yog sib npaug rau lub zog tensile, tab sis cov ntawv thiab cov welds negate qhov txiaj ntsig no. Cov ntsiab lus kho ntawm Q690E tuaj yeem ua tau zoo dua qhov tsis tau kho, tab sis cov ntsiab lus tsis zoo ntawm Q690E tuaj yeem ua tsis tau sai dua li qis dua - qib steel.
TSIS TXHOB ua cov nplaim taws ncaj los yog tsis muaj kev tswj xyuas cov cua sov, uas tuaj yeem tsim cov nkig.
Summary: Txoj Kev Fatigue Enhancement Pathway rau Q690E Ntauwd
Tsim rau Smoothness: Ua ntej tshaj plaws ntawm cov ncauj lus kom ntxaws tshaj plaws los ntawm qhov pib.
Fabricate nrog Precision: Ua kom haum zoo -nce, qis- hydrogen vuam, thiab flawless profiles.
Kho cov Welds: Siv UIT/HiFIT rau txhua qhov tseem ceeb vuam ntiv taw-qhov no yog ib kauj ruam zoo tshaj plaws los txhawb Q690E lub peev xwm.
Txo Kev Nyuaj Siab Thoob Ntiaj Teb: Siv PWHT rau cov ntu tuab kom txo qis kev ntxhov siab.
Tiv thaiv los ntawm Corrosion: Siv thiab tuav lub siab - txheej txheej txheej.
Hauv kev xaus, txhim kho qhov qaug zog ntawm Q690E hauv cov cua yees tsis yog hais txog cov khoom siv hauv paus ib leeg; nws yog hais txog kev tsim ib qho "zoo meej" welded qauv uas muaj kev ntxhov siab tsawg tsawg, thiab cov kev ntxhov siab seem raug tswj los yog ua kom muaj txiaj ntsig. Kev nqis peev hauv kev tsim qauv zoo tshaj, kev tsim khoom siv hluav taws xob, thiab kev tshaj tawm qib siab -weld kev kho mob yog qhov tseem ceeb los qhib kev lag luam thiab kev ua tau zoo ntawm kev siv qhov ultra- siab- lub zog steel rau cov ntawv thov uas xav tau.