Xov xwm
0102 ib0304 ib05
Lub rail grinidng cov tswv yim
2024-10-28 IB
Kev tsheb ciav hlau tsis tu ncua txo lossis tshem tawm cov tsheb ciav hlau puas tsuaj thiab txuas ntxiv lawv lub neej kev pabcuam, uas tau lees paub tias yog ib txoj hauv kev zoo hauv kev tsheb ciav hlau. Raws li tus cwj pwm ntawm kev puas tsuaj ntawm kev tsheb ciav hlau thiab ua ke nrog cov kev xav tau ntawm kev thauj mus los ntawm kev tsheb ciav hlau, kev tsheb ciav hlau grinidng technology thiab cov cuab yeej tsim kho nyob rau hauv ntau theem thiab ntau haiv neeg. Cov tswv yim tseem ceeb rau kev sib tsoo tsheb ciav hlau muaj xws li kev sib tsoo ua ntej, kev tiv thaiv kev sib tsoo, thiab kho kev sib tsoo.
Ua ntej sib tsoo. Thaum lub sij hawm kub dov txheej txheem ntawm cov ntsia hlau, qhov kub thiab txias ua rau cov oxidation ntawm cov pa roj carbon thiab hlau nyob rau saum npoo ntawm cov ntsia hlau. Thaum oxidation tus nqi ntawm cov pa roj carbon ntau dua li cov hlau, qee cov cementite hauv pearlite hloov mus rau ferrite, ua rau cov txheej txheem decarburization, raws li qhia hauv Fig.1. Lub hardness, lub zog, thiab hnav tsis kam ntawm decarburization txheej ntawm cov tsheb ciav hlau yog qis dua cov substrate [1]. Thaum lub sijhawm ua haujlwm, cov kab nrib pleb feem ntau nthuav tawm raws cov ferrite, uas yuav ua rau muaj kev puas tsuaj loj rau txoj kev tsheb ciav hlau [2]. Thaum lub sij hawm tsim kho ntawm txoj kab tshiab, nquag pib / nres ntawm kev tsim kho tsheb tuaj yeem yooj yim ua rau kev tsheb ciav hlau khawb thiab lwm yam teeb meem. Rail khawb tsis yooj yim pom los ntawm cov neeg ua haujlwm soj ntsuam thaum ntxov, tab sis kev sib txhuam ntawm lub log thiab cov tsheb ciav hlau ua rau kev hloov pauv ntawm metallographic hauv thaj tsam khawb ntawm txoj kev tsheb ciav hlau, uas tuaj yeem tsim kev puas tsuaj loj hauv kev pabcuam tom qab [3]. Yog li ntawd, rau kev tsim kho cov kab tshiab thiab tso cov kab tshiab rau hauv cov ntu, kev sib tsoo ua ntej yuav tsum tau ua tom qab commissioning thiab ua ntej qhib kev ua haujlwm kom tshem tawm cov txheej txheem decarburization txog li 0.2 hli ntawm qhov chaw thiab kev puas tsuaj los ntawm kev tsim kho. Rau cov kab uas twb tau muab tso rau hauv kev ua haujlwm, nws yuav tsum tau ua kom tiav ua ntej sib tsoo ua ntej dhau qhov loj ntawm 10 Mt.
Fig. 1.Lub decarburization txheej ntawm railhead.
Tiv thaiv kev sib tsoo. Rau qhov tsis xws luag xws li corrugation, delamination, lateral abrasion, thiab crushing, nws yog ib qho tsim nyog yuav tsum tau siv qhov sib tsoo loj dua kom tshem tawm qhov tsis xws luag, thiab tib lub sij hawm kho thiab kho cov kev tsheb ciav hlau. Nyob rau ntawm lub sijhawm no, cov khoom siv tsheb ciav hlau tshem tawm thiab qhov tob ntawm kev sib tsoo yog qhov loj, thiab qhov kev sib tsoo no hu ua reparative sib tsoo. Raws li kev tsim qauv hnav siab ntev ntawm lub tsheb ciav hlau sab saum toj, qhov zaus ntawm kev hloov tsheb ciav hlau tau nce thaum kho kev sib tsoo, ua rau kev sib tsoo tsis zoo.
Tuam Tshoj tau ua kom pom tseeb cov kev cai ntawm kev kho kev sib tsoo ntawm txoj kev tsheb ciav hlau: (a) Kev kho kev sib tsoo yuav tsum xaiv cov khoom sib tsoo uas tsim nyog thiab kev ua haujlwm tsis zoo raws li cov yam ntxwv ntawm kev tsheb ciav hlau tsis xws luag, tshem tawm cov tsheb ciav hlau tsis xws luag, thiab kho cov tsheb ciav hlau; (b) Nyob rau hauv cov kab zoo tib yam, rau qhov tsis xws luag xws li yoj sib tsoo qhov tob lossis rog ntug dav tshaj 0.3 hli, kev kho kom raws sij hawm sib tsoo yuav tsum tau teeb tsa; (c) Nyob rau hauv high-speed railway kab, thaum muaj kev kub ceev tsheb ciav hlau co, lateral acceleration tswb ntawm lub transverse ncej, tsis zoo lub teeb sawb nyob rau hauv seem, ntses nplai qhov tob ntawm turnout rail ncav cuag 0.5 hli, taug qab qhov cuam tshuam cov lus teb Performance index tshaj qhov kev tswj tus nqi, los yog rail defects mus txog lub reconstruction txwv, raws sij hawm kho thiab sib tsoo ntawm lub tsheb ciav hlau yuav tsum tau.
Kho kev sib tsoo. Txoj kev tsheb ciav hlau tau raug thauj mus los ntawm lub log, thiab cov txheej txheem kev sib cuag lub zog (RCF) yog tsim rau saum npoo ntawm txoj kev tsheb ciav hlau vim "ratchet effect" [4,5]. Nyob rau hauv lub dov kev sib cuag qaug zog txheej, lub hardness thiab brittleness ntawm cov ntaub ntawv rail nce ho, thiab lub microstructure qhia tau hais tias ib tug nce nyob rau hauv dislocation ceev thiab microcrack pib [5]. Kev nthuav tawm sab nraud thiab ntev ntawm microcracks tuaj yeem ua rau muaj kev puas tsuaj xws li delamination thiab rail breakage hauv rails [1]. Nyob rau hauv lub voj voog kev loj hlob (nucleation, pib, thiab propagation), nucleation thiab pib lub sij hawm account rau ib tug loj feem. Kev sib tsoo feem ntau yog ua tiav thaum qhov tob ntawm qhov tawg tsis pub dhau 0.2 hli, uas yog lub sijhawm zoo tshaj plaws los thaiv kev nthuav tawm ntawm txoj kev tsheb ciav hlau thiab tsis txhob cuam tshuam ntxiv ntawm txoj kev tsheb ciav hlau, raws li tau hais hauv Fig.2. Raws li cov txheej txheem ntawm dov kev sib cuag qaug zog ntawm qhov chaw ntawm cov ntsia hlau thiab txoj cai ntawm kev sib tsoo, kev tiv thaiv kev sib tsoo yog npaj, uas yuav tsum tsis tu ncua tshem tawm cov dov kev sib cuag qaug zog txheej ntawm cov ntsia hlau. Kev tiv thaiv kev sib tsoo muaj qhov sib tsoo me me, uas yog qhov tsim nyog rau kev siv lub neej ntev ntawm kev sib tsoo thiab muaj kev sib tsoo kev lag luam zoo dua piv rau kev kho kev sib tsoo.
Tuam Tshoj Railway Corporation tau tshaj tawm cov kev cai meej rau kev siv kev tiv thaiv kev sib tsoo ntawm kev tsheb ciav hlau. (a) Rau kev tsheb ciav hlau ceev ceev, kev tiv thaiv kev sib tsoo yuav tsum tau nqa tawm txhua 30-50 Mt ntawm tag nrho qhov hnyav, nrog rau kev sib tsoo tsis pub dhau 2 xyoos. (b) Rau txoj kab ncaj nraim thiab loj nkhaus nkhaus (> 1200 m) ntawm cov kab ceev zoo tib yam, cov txheej txheem sib tsoo feem ntau ua tiav ib zaug rau tag nrho qhov hnyav ntawm 100 Mt; rau cov seem me me ( 
Txoj cai evolution ntawm kev pab cuam lub neej ntawm cov ntsia hlau raws li cov tswv yim sib tsoo sib txawv yog qhia hauv daim duab 2, thiab cov txiaj ntsig tau qhia tias kev sib tsoo tuaj yeem txuas tau lub neej kev pab cuam ntawm cov ntsia hlau. Raws li cov lus ceeb toom, qhov tshwm sim ntawm qhov tsis xws luag tshwm sim ntawm qhov chaw ntawm kev sib tsoo tom qab tsis sib tsoo, kho kev sib tsoo, thiab kev tiv thaiv kev sib tsoo yog 15%, 8%, thiab 4%, raws li [6], qhia tias kev tiv thaiv kev sib tsoo muaj txiaj ntsig zoo hauv kev txo qis qhov tshwm sim ntawm kev tsheb ciav hlau tsis xws luag. Tsis tas li ntawd, kev tiv thaiv kev sib tsoo cov ntaub ntawv muaj qhov me me tshem tawm tuab, uas tuaj yeem txuas ntxiv lub neej kev pab cuam ntawm kev sib tsoo piv rau kev kho kev sib tsoo. Raws li qhov xwm txheej loj ntawm kev loj hlob sai ntawm kev lag luam thiab kev thov ceev ceev rau kev thauj mus los ntawm Tuam Tshoj txoj kev tsheb ciav hlau, kev siv kev tiv thaiv kev sib tsoo tuaj yeem ua tau zoo txuas ntxiv rau kev hloov tsheb ciav hlau thiab muaj kev sib tsoo ntau dua. Predictive tiv thaiv kev sib tsoo yog lub ntsiab kev loj hlob kev taw qhia ntawm yav tom ntej rail sib tsoo tshuab.
Fig.2.Kev nthuav tawm tus cwj pwm ntawm dov kev sib cuag fatgiue tawg
Fig.3.Kev sib raug zoo ntawm kev sib tsoo cov tswv yim thiab kev pab cuam lub neej ntawm rails
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