Codelco kom ncua El Teniente mine expansion, hais txog kev sib kis

Chile lub xeev Codelco tau hais rau hnub Saturday nws yuav txwv kev tsim kho ib ntus ntawm qib tshiab ntawm nws qhov tseem ceeb El Teniente mine, ib qho kev txav uas nws tau hais tias yog qhov tsim nyog los tawm tsam tus kabmob kis tau sai.

Cov neeg tsim khoom loj tshaj plaws hauv ntiaj teb Codelco tau hais hauv nqe lus tias qhov kev ntsuas yuav ua rau tag nrho cov neeg ua haujlwm txo qis ntawm nws cov haujlwm Teniente rau 4,500 tus neeg. Lub mine yuav ua haujlwm txuas ntxiv nrog rau lub sijhawm ua haujlwm tau tshaj tawm yav dhau los ntawm 14 hnub rau thiab 14 hnub so los tiv thaiv cov neeg ua haujlwm, lub tuam txhab tau hais.

"Qhov no (kev ntsuas) tau pib ua tiav rau lub asthiv dhau los," Codelco tau hais tias, ntxiv qhov kev txav mus los yog tsom rau "txo qhov ntom ntom ntawm peb tus kheej thiab cov neeg ua haujlwm cog lus, ua kom rov qab txav mus thiab txo qhov muaj feem kis tau."

Qhov kev txiav txim siab los ntawm Federation of Copper Workers (FTC), ib pab pawg lub kaus rau Codelco cov koom haum, tshaj tawm cov neeg ua haujlwm cog lus ntawm El Teniente tau tuag los ntawm covid-19, thib rau kev tuag los ntawm tus kabmob ntawm lub tuam txhab kev ua haujlwm.

Cov koom haum hais tias tsawg kawg 2,300 ntawm Codelco cov neeg ua haujlwm tau kis tus kabmob no txij li thaum muaj kev sib kis pib thaum nruab nrab Lub Peb Hlis.

Tus kab mob coronavirus tau ntes Codelco nyob rau hauv nruab nrab ntawm 10-xyoo, $ 40 txhiab daus las pib pib txhim kho nws cov mines laus. Txoj haujlwm El Teniente yuav txuas ntxiv lub neej ua haujlwm ntawm lub xyoo pua xyoo mine, nyob hauv Andes Roob sab qab teb ntawm lub nroog Santiago.

Cov koom haum thiab cov pab pawg neeg sib raug zoo tau txhawb nqa rau Codelco thiab lwm cov neeg ua haujlwm mining kom muaj kev tiv thaiv rau cov neeg ua haujlwm, suav nrog cov lus pom zoo rau lub lim tiam no kom kaw cov mines sab qaum teb ntawm Teniente, hauv thaj av Antofagasta, rau ob lub lis piam.

Codelco CEO Octavio Araneda tau hais hauv kev xam phaj nrog xov xwm hauv zos rau hnub Thursday tias txhua qhov kev txav no yuav yog "kev puas tsuaj" rau lub tebchaws. Nws tiv thaiv lub tuam txhab cov lus teb tus kab mob ua haujlwm.

Lub tuam txhab tau hais tias nws yuav txuas ntxiv nrog kev npaj thiab npaj rau Teniente nthuav dav txawm tias muaj kev poob qis. Peak kev tsim kho yuav tsum nyob rau hauv 2021 thiab 2022, tsab ntawv hais tias.

El Teniente tau tsim 459,744 tonnes ntawm tooj liab hauv 2019.

Kawm txog cov tsis tshua muaj alloy hnav-resistant steel rau shredder hammers

High manganese steel yog siv dav hauv kev nrum me me rauj (feem ntau tsawg dua 90kg). Txawm li cas los xij, rau cov hlau recycle shredder rauj (feem ntau hnyav ib ncig ntawm 200kg-500kg), manganese steel tsis haum. Peb lub tuam txhab siv cov hlau tsis tshua muaj hlau rau casting loj shredder hammers.

Kev xaiv cov khoom siv

Kev tsim qauv ntawm cov hlau alloy yuav tsum tau txiav txim siab ua kom tau raws li qhov yuav tsum tau ua ntawm cov alloy. Lub hauv paus ntsiab lus tsim yog los xyuas kom meej txaus hardenability thiab siab hardness thiab toughness. Cov kev ntxhov siab sab hauv ntawm bainite feem ntau qis dua li ntawm martensite, thiab hnav tsis kam ntawm bainite zoo dua li ntawm martensite ntawm tib lub hardness. Cov txheej txheem ntawm cov hlau alloy raws li hauv qab no:

Carbon Element.  Cov pa roj carbon monoxide yog lub hauv paus tseem ceeb cuam tshuam rau microstructure thiab cov khoom ntawm cov hlau tsis tshua muaj thiab nruab nrab alloy hnav-resistant steel. Cov ntsiab lus carbon sib txawv tuaj yeem tau txais qhov sib txawv ntawm kev sib raug zoo ntawm hardness thiab toughness. Tsawg carbon alloy muaj zog dua tab sis qis hardness, siab carbon alloy muaj siab hardness tab sis tsis txaus toughness, thaum nruab nrab carbon alloy muaj siab hardness thiab zoo toughness. Txhawm rau kom tau txais kev ua haujlwm siab kom ua tau raws li cov kev pabcuam ntawm qhov loj thiab tuab hnav-tiv taus qhov cuam tshuam loj, qhov ntau ntawm cov pa roj carbon tsawg yog 0.2 ~ 0.3%.

Si Element.  Si tsuas yog ua lub luag haujlwm ntawm kev daws teeb meem hauv cov hlau, tab sis siab dhau Si yuav ua rau cov hlau tsis muaj zog, yog li nws cov ntsiab lus yog 0.2 ~ 0.4%.

Mn Element.  Tuam Tshoj yog nplua nuj nyob rau hauv manganese cov peev txheej thiab cov nqi qis, yog li nws tau dhau los ua cov khoom siv tseem ceeb ntawm cov hlau tsis tshua muaj hlau tsis muaj hlau. Ntawm qhov tod tes, manganese nyob rau hauv cov hlau ua lub luag haujlwm ntawm kev daws teeb meem los txhim kho lub zog thiab hardness ntawm cov hlau, thiab ntawm qhov tod tes, nws txhim kho cov hardenability ntawm cov hlau. Txawm li cas los xij, ntau dhau ntawm manganese yuav ua rau kom cov ntim austenite khaws cia, yog li cov ntsiab lus manganese txiav txim siab yog 1.0-2.0%.

Cr Element.  Cr plays lub luag haujlwm tseem ceeb hauv cov hlau tsis tshua muaj hnav-resistant cam khwb cia hlau. Cr tuaj yeem ua ib feem yaj hauv austenite kom ntxiv dag zog rau cov matrix yam tsis tas yuav txo qhov toughness, ncua kev hloov pauv ntawm undercooled austenite thiab nce hardenability ntawm hlau, tshwj xeeb tshaj yog thaum ua ke nrog manganese thiab silicon, hardenability tuaj yeem txhim kho tau zoo. Cr muaj ntau dua tempering tsis kam thiab tuaj yeem ua rau cov khoom ntawm lub ntsej muag tuab tuab. yog li cov ntsiab lus Cr tau txiav txim siab yog 1.5-2.0%.

Mo Element.  Mo tuaj yeem txhim kho cov txheej txheem zoo li-cam khwb cia, txhim kho qhov sib xws ntawm ntu ntu, tiv thaiv qhov tshwm sim ntawm temper brittleness, txhim kho tempering stability, thiab cuam tshuam toughness ntawm steel. Cov txiaj ntsig tau pom tias qhov hardenability ntawm steel yog qhov zoo dua, thiab lub zog thiab hardness ntawm cov hlau tuaj yeem txhim kho. Txawm li cas los xij, vim yog tus nqi siab, qhov sib ntxiv ntawm Mo yog tswj ntawm 0.1-0.3% raws li qhov loj thiab phab ntsa thickness ntawm qhov chaw,.

Ni Element.  Ni yog lub ntsiab alloy tsim thiab stabilize austenite. Ntxiv ib qho nyiaj ntawm Ni tuaj yeem txhim kho lub hardenability thiab ua rau lub microstructure khaws cia me me ntawm austenite nyob rau hauv chav tsev kub los txhim kho nws cov toughness. Tab sis tus nqi ntawm Ni yog siab heev, thiab cov ntsiab lus ntawm Ni ntxiv yog 0.1-0.3%.

Cu Element.  Cu tsis tsim carbides thiab muaj nyob rau hauv cov matrix raws li ib tug khoom tov, uas yuav txhim khu lub toughness ntawm hlau. Tsis tas li ntawd, Cu muaj cov nyhuv zoo sib xws rau Ni, uas tuaj yeem txhim kho lub hardenability thiab electrode peev xwm ntawm matrix, thiab ua rau kom corrosion kuj ntawm hlau. Qhov no yog qhov tseem ceeb tshwj xeeb tshaj yog rau cov khoom hnav-tiv taus ua haujlwm nyob rau hauv kev sib tsoo ntub dej. Qhov sib ntxiv ntawm Cu nyob rau hauv hnav-resistant steel yog 0.8-1.00%.

Kab Element.  Ntxiv cov kab hauv qab rau hauv cov hlau uas tsis tshua muaj hnav-resistant steel yog ib txoj hauv kev zoo tshaj plaws los txhim kho nws cov khoom. Nws tuaj yeem ua kom zoo li-cam khwb cia microstructure, purify grain ciam teb, txhim kho lub morphology thiab faib ntawm carbides thiab inclusions, thiab tuav txaus toughness ntawm tsawg alloy hnav-resistant steel.

SP Element.  Lawv yog cov khoom tsis zoo, uas yooj yim tsim cov ciam teb suav nrog hauv cov hlau, ua rau kom cov hlau tsis huv thiab ua rau kom muaj kev sib tsoo ntawm cov castings thaum lub sij hawm casting thiab kev kho cua sov. Yog li, P thiab s yuav tsum tsawg dua 0.04%.

Yog li cov tshuaj muaj pes tsawg leeg rau alloy hnav-resistant steel yog qhia nyob rau hauv cov lus hauv qab no:

Smelting txheej txheem

Cov khoom siv raw tau yaj hauv 1 T nruab nrab zaus induction rauv. Cov hlau yog npaj los ntawm cov hlau seem, npua hlau, qis carbon ferrochrome, ferromanganese, ferromolybdenum, electrolytic npib tsib xee, thiab tsawg lub ntiaj teb alloy. Tom qab melting, cov qauv raug coj mus rau kev tshuaj ntsuam xyuas ua ntej lub cub tawg, thiab cov hlau yog ntxiv raws li kev soj ntsuam cov txiaj ntsig. Thaum muaj pes tsawg leeg thiab kub ua tau raws li qhov yuav tsum tau ua ntawm tapping, aluminium yog ntxig rau deoxidize; Thaum lub sij hawm tapping txheej txheem, tsis tshua muaj ntiaj teb Ti thiab V ntxiv rau kev hloov kho.

Pouring & Casting

Xuab zeb pwm casting yog siv nyob rau hauv cov txheej txheem molding. Tom qab cov hlau molten yog tawm ntawm lub cub tawg, nws yog muab tso rau hauv lub ladle. Thaum qhov kub thiab txias poob rau 1450 ℃, lub ncuav pib. Txhawm rau ua kom cov hlau molten sau cov xuab zeb pwm sai sai, yuav tsum tau siv lub rooj vag loj (20% loj dua li cov pa roj carbon zoo tib yam) yuav tsum tau txais. Txhawm rau txhim kho lub sijhawm pub mis thiab pub muaj peev xwm ntawm cov riser, cov hlau txias yog siv los ua kom haum rau cov riser thiab cov txheej txheem cua sov sab nraud tau txais yuav kom tau txais cov qauv ntom ntom. Qhov loj ntawm lub ncuav loj shredder rauj yog 700 mm * 400 mm * 120 mm, thiab qhov hnyav ntawm ib thooj yog 250 kg. Tom qab lub casting yog ntxuav, high-temperature annealing yog nqa tawm, thiab ces lub rooj vag thiab riser yog txiav.

Kev kho cua sov

Cov txheej txheem quenching thiab tempering cua sov yog siv. Txhawm rau tiv thaiv quenching tawg ntawm lub qhov installation, txoj kev quenching hauv zos tau txais yuav. Lub thawv-hom tsis kam rauv tau siv los ua kom sov lub casting, austenitizing kub yog (900 ± 10 ℃) thiab tuav lub sij hawm yog 5 h. Qhov txias txias ntawm cov dej tshwj xeeb iav quenchant yog nruab nrab ntawm dej thiab roj. Nws yog qhov zoo heev los tiv thaiv quenching tawg thiab quenching deformation, thiab qhov nruab nrab quenching muaj tus nqi qis, kev nyab xeeb zoo, thiab kev ua tau zoo. Tom qab quenching, cov txheej txheem tempering qis yog txais yuav, qhov kub thiab txias yog (230 ± 10) ℃ thiab lub sijhawm tuav yog 6 h.

Kev Tswj Xyuas Zoo

Cov ntsiab lus tseem ceeb ntawm cov hlau tau ntsuas los ntawm optical dilatometer dt1000, thiab isothermal transformation nkhaus ntawm undercooled austenite yog ntsuas los ntawm metallographic hardness txoj kev.

TTT nkhaus ntawm cov hlau alloy

Los ntawm TTT txoj kab nkhaus, peb tuaj yeem paub:

1. Muaj cov cheeb tsam Bay pom tseeb ntawm qhov kev hloov pauv ntawm qhov kub thiab txias ferrite, pearlite, thiab nruab nrab kub bainite. C-curve ntawm pearlite transformation yog sib cais los ntawm bainite transformation, uas qhia cov tsos txoj cai ntawm ywj siab C-kov, uas belongs rau ob "lub qhov ntswg" hom, thaum lub bainite cheeb tsam yog ze rau S-khov. Vim tias cov hlau muaj cov carbide tsim cov ntsiab lus Cr, Mo, thiab lwm yam, cov ntsiab lus no yaj mus rau hauv austenite thaum cua sov, uas tuaj yeem ncua qhov decomposition ntawm undercooled austenite thiab txo nws cov decomposition tus nqi. Nyob rau tib lub sijhawm, lawv kuj cuam tshuam rau qhov decomposition kub ntawm undercooled austenite. Cr thiab Mo ua rau thaj tsam pearlite hloov mus rau qhov kub thiab txias thiab txo qhov kub ntawm bainite transformation. Nyob rau hauv txoj kev no, lub transformation nkhaus ntawm pearlite thiab bainite yog sib cais nyob rau hauv lub TTT nkhaus, thiab ib tug subcooled austenite metastable cheeb tsam tshwm nyob rau hauv nruab nrab, uas yog hais txog 500-600 ℃.
2. Qhov kub ntawm lub qhov ntswg ntawm cov hlau yog li 650 ℃, ferrite hloov kub ntau yog 625-750 ℃, pearlite transformation kub yog 600-700 ℃, thiab bainite transformation kub ntau yog 350-500 ℃.
3. Nyob rau hauv lub high-temperature transformation cheeb tsam, lub sij hawm ntxov tshaj plaws rau precipitate ferrite yog 612 s, lub shortest incubation lub sij hawm ntawm pearlite yog 7 270 s, thiab lub transformation tus nqi ntawm pearlite mus txog 50% ntawm 22 860 s; Lub sij hawm incubation ntawm bainite transformation yog hais txog 20 s ntawm 400 ℃ thiab martensite transformation tshwm sim thaum kub qis dua 340 ℃. Nws tuaj yeem pom tias cov hlau muaj zoo hardenability.

Mechanical Property

Cov qauv raug coj los ntawm kev sim ua kom loj shredder rauj lub cev, thiab 10 mm * 10 mm * 20 mm strip qauv raug txiav los ntawm cov hlau txiav los ntawm sab nraud mus rau sab hauv, thiab qhov hardness yog ntsuas los ntawm qhov chaw mus rau qhov chaw. Txoj hauj lwm piv txwv yog qhia nyob rau hauv daim duab 2. #1 thiab #2 yog muab los ntawm shredder rauj lub cev, thiab #3 yog coj ntawm lub installation qhov. Cov txiaj ntsig ntawm kev ntsuas hardness yog qhia hauv Table 2.

Daim duab ntawm shredder rauj

Nws tuaj yeem pom los ntawm Table 2 tias qhov hardness HRC ntawm lub rauj lub cev (#1) yog ntau dua 48.8, thaum lub hardness ntawm lub mounting qhov (#3) kuj qis dua. Lub cev rauj yog qhov tseem ceeb ua haujlwm. Lub siab hardness ntawm rauj lub cev tuaj yeem ua kom muaj kev hnav tsis kam; qhov tsawg hardness ntawm lub qhov mounting yuav muab siab toughness. Nyob rau hauv txoj kev no, qhov kev ua tau zoo sib txawv ntawm qhov sib txawv tau ua tiav. Los ntawm ib qho piv txwv, nws tuaj yeem pom tias qhov nyuaj ntawm qhov chaw feem ntau siab dua li cov tub ntxhais hardness, thiab qhov hardness fluctuation range tsis loj heev.

Cov ntaub ntawv ntawm kev cuam tshuam toughness, tensile zog, thiab elongation yog qhia nyob rau hauv Table 3. Nws tuaj yeem pom los ntawm Table 3 tias qhov cuam tshuam toughness ntawm U-shaped Charpy specimen ntawm rauj yog siab tshaj 40 J / cm2, thiab lub siab tshaj plaws toughness ntawm mounting qhov yog 58.58 J / cm * cm; Qhov elongation ntawm cov qauv cuam tshuam yog ntau tshaj 6.6%, thiab lub zog tensile yog ntau tshaj 1360 MPa. Qhov cuam tshuam toughness ntawm cov hlau yog siab dua li ntawm cov hlau tsis tshua muaj hlau (20-40 J / cm2). Feem ntau hais lus, yog tias hardness siab dua, lub toughness yuav txo. Los ntawm cov txiaj ntsig kev sim saum toj no, nws tuaj yeem pom tau tias txoj cai no yog qhov pib ua raws li nws.

Microstructure

Microstructure ib qho qauv me me raug txiav los ntawm qhov kawg ntawm cov qauv cuam tshuam, thiab tom qab ntawd cov qauv metallographic tau npaj los ntawm kev sib tsoo, ua ntej sib tsoo thiab polishing. Kev faib tawm ntawm kev suav nrog tau pom nyob rau hauv qhov xwm txheej tsis muaj kev yaig, thiab cov qauv matrix tau pom tom qab raug eroded nrog 4% nitric acid cawv. Ob peb cov qauv ntawm alloy shredder hammers muaj nyob rau hauv daim duab 3.

Daim duab 3 Lub microstructures ntawm shredder rauj daim duab 3A qhia txog morphology thiab kev faib ntawm cov inclusions nyob rau hauv cov hlau. Nws tuaj yeem pom tau tias tus naj npawb thiab qhov loj ntawm kev suav nrog yog me me, tsis muaj cov kab noj hniav shrinkage, shrinkage porosity, thiab porosity. Los ntawm cov duab 3b, C, D, thiab E, nws tuaj yeem pom tias ob qho tib si ze-nto thiab ze ntawm qhov chaw.

Cov txiaj ntsig tau pom tias cov qauv hardened yog tau los ntawm qhov chaw mus rau qhov chaw, thiab txaus hardenability tau txais. Lub microstructure nyob ze ntawm qhov chaw yog coarser tshaj qhov saum npoo vim hais tias cov tub ntxhais yog qhov kawg solidification qhov chaw, qhov cua txias yog qeeb thiab cov nplej tau yooj yim loj hlob.

Lub matrix nyob rau hauv daim duab 3b thiab C yog lath martensite nrog uniform tis. Lub lath nyob rau hauv daim duab 3b yog me me, thiab lub lath nyob rau hauv daim duab 3C yog cov tuab, thiab ib co ntawm lawv yog teem ntawm 120 ° kaum. Cov txiaj ntsig tau pom tias qhov nce ntawm martensite tom qab quenching ntawm 900 ℃ feem ntau yog raws li qhov tseeb tias cov nplej loj ntawm cov hlau nce sai sai tom qab quenching ntawm 900 ℃. Fig. 3D thiab e qhia zoo martensite thiab qis bainite nrog me me thiab granular ferrite. Qhov chaw dawb yog quenched martensite, uas yog corrosion-resistant dua bainite, yog li cov xim yog sib dua; cov qauv zoo li rab koob dub yog qis dua bainite; qhov chaw dub yog suav nrog.

Vim hais tias lub installation qhov ntawm lub shredder rauj yog txias nyob rau hauv cov huab cua thiab lub quenching kub yog tsawg, lub ferrite tsis tau kiag li yaj mus rau hauv lub matrix. Yog li ntawd, ib tug me me ntawm ferrite tseem nyob rau hauv lub martensite matrix nyob rau hauv daim ntawv ntawm me me pieces thiab hais, uas ua rau kom txo hardness.

Cov txiaj ntsig

Tom qab casting, peb xa ob txheej ntawm shredder rauj rau peb cov neeg siv khoom, ib txheej ntawm alloy hnav-resistant steel shredder hammers, ib txheej ntawm manganese steel shredder hammers. Raws li cov neeg siv khoom tawm tswv yim, alloy hnav-resistant steel shredder hammers ncua lub neej 1.6 npaug ntau dua manganese shredder rauj.

@Nick Sun      [email protected]