1^^ KHOA HOC VA C O H G NGHE MO
\ SUT DUNG THIET Bl CO DONG VA CONG NGHE UNH HOAT
DE KHAI THAC CAC NUI DA XAY DUNG ]
TRONG Din HINH PHU'C TAP VA KICH THlfdC HRN CH€
GS.TS. TRAN MANH XUAN, NCS. HOANG CAO PHUONG
Trwimg Dpi hgc Mo-Dja chat
1
H gdy nay, fren cdc mg Id ttiien may xiic tay gau chgy diesel kit hyp vdi 0 tO khung ngdn duae eoi Id dong bO thilt bi eo dgng lam vifc cO hifu qua trong dieu kifn dja hinh phde tgp vd mat bang hogt dfng cO kich thudc hgn chl. Td khi may chit tai dyyc dua vdo sd dyng trong ngdnh mo vdi dung tieh gau Idn, cO chde nang chat hogc xuc chdt va vgn tai dd trd thdnh togi thift bj co dgng co t h l canh franh vdi dong bf mdy xOc-d td d ehdng mye nhdt djnh phu thufc vdo khoang each van tai va san luyng mo. Theo cdc tai lifu nghifn cdu d nudc ngodi cQng nhu kinh nghifm su dung thyc t l d nude ta, may chat tai Idm chde ndng xCic bdc, van tai lam viec eO hifu qua ban dong bg mdy xue-0 td khi khoang cdch vdn tai vdt lieu din 1000 m vd san luong md d n hodn thdnh din 1 frif u m%am.
Khi khai thdc cdc md da vdi vd da xdy dyng la cae nCii don ddc hay cdc mdm nui nam gdn nhau frong mpt quan thf nui dd cd kich thudc Idn, eO t h l sd dyng cae dong bf ttiilt bj frf n ddy vdi eae so do cdng nghf linh hogt, nham ndng cao frinh dp ea gidi hod frong khai thdc If thifn, dam bao an todn, tan thu duoc toi da tdi nguyfn vd bao vf mdi trudng.
o l khai thdc ede mo da xdy dyng ed dang nhu trfn, thudng ngydi ta dp dyng phuong phap md via bdng hdo hode hdo-mdng. Tuyin dudng hdo cO dgng xoln oc. Cac thOng so co ban cua hdo: dp ddc dgc cua dudng hdo i (%); chifu rdng cua nfn hdo b (m) va chilu cao cua bd hdo h (m). Cdc thdng sd nay cd anh hudng quylt djnh din kha nang dp dyng cua tung loai dong bd thilt bj, hieu qua khai thdc dOi vdi mpt md cu the cO kich thudc chdn nOi vd gdc die cua sudn nui xdc djnh. Chilu rpng nfn hao duyc xdc djnh phy'thupc vao phuong tifn di ehuyfn fren hdo (0 td, mdy chit tai hoae ttiiet bj xuc bOc) ed tinh dfn chifu rpng dai an todn, rdnh thoat nudc. Chilu eao cua hdo duyc xdc djnh theo bilu thdc:
. b.siny.sina
h = ^—~ ,m. (1) sin(a-Y)
Trong dd: b - Chieu rpng cua nin hdo, m; y, a - Goc die trung binh cua sudn nui vd bd hao, do.
Tu (1) ta thiy chieu cao cua hdo phy ttiuge vao chilu rdng cua nin hdo (b) vd gdc die sudn nui y (H.I). .
H.f. Syphu thugc chieu cao hao h va chieu rdng
nen hdo vd gdc doc trung binh cua sudn nOi ,-,Td hinh H.I ta Uiay khi chilu rdng nfn hao cho trude thi nlu gdc doc tnjng binh cua sudn nCii y tii' 40° trd xulng chilu cao eua hdo h tang td td, nhung khi Y>40°, gid tri h tang rat nhanh, dilu dd eho tti^
kha ndng ddo hdo xoan l e frf n sudn nOi ed dO d ^ cao se bj hgn c h l dae bift khi nfn hdo rgng. *'
1. Su dung ddng bp thilt bj may xuc-6 to ^ • Day Id ding bf ttiilt bi phd ttidng nhdt khi khat ttiae cde md dd. Tuy nhien dilu kifn dp dung khd ng#
ngheo dfc bift khi kich Uiude nQi bi ban chi vd g6#
CfiNGNGHliPM0.Sfi4-2015
KHOA HOC VA C O N G NGHE M O
J j ^ ^
dOc sudn nui Idn. Khi sd dyng, v( dy 1 may xuc d l
<uc dd fren tdng ttii phii hop vdi nO it nhdt Id 2 o tO xd Ifn, dieu dd ddn den chilu rgng nin hdo Idn, lam ang chieu eao eua hdo (dudng hai Idn xe). Oilu ndy jdn den hgn c h l kha ndng dp dyng eua edng nghf lay do chilu eao nQi dyyc md via bing hao xoln l e j | van tai bang d td khOng Idn.
2. Cong nghe ddng bo t h i l t bj may chalt tai-6 to Cgnh franh vdi cOng nghe frinh bdy tren ddy chQng a cd ttil dp dyng cdng nghe khdc cO tinh linh boat ian Thay cho may xiic, chung ta dQng mdy chit tdi.
Wdy chit tai lam nhifm vu xuc dit dd fren tdng (khau Iheo ldp bang) sau dO van chuyin da chgy theo sudn lui xuong dd tai vao d tO bo fri d chdn nui. Nfn su dung chl 1 may chit tai d l xiic boc. Dilu ndy eho Dhep giam kich thudc cua nin hdo. Mgt khac, mdy :h_dt tai eO kha nang vugt dp ddc Idn ban d td nfn ed h i giam 6itac khoang each van tai td mat bdng khai hdc din chdn nui. San luong md Qa cd till dat duyc rang trudng hyp ndy phy thudc vao nang suit cua
•nay chat tai Qd, nd duyc xac djnh theo bieu thdc:
Qci=Qci=EK^nKo,, m^/h. (2) Td (2) ta tinh duyc dung tinh giu mdy chat tai
: l n ttiilt khi bilt san lyyng da Qtj:
Trong dd: E - Dung tich gdu cua mdy chdt tai, m^; n
• So ehu k^ xQc ly thuylt trong 1 gid.
n=(60/to0=[60/(txd+tc)]. (4) Tgi day: TCK - Thai gian chu ky lam viec (chu kJ
<uc) cOa may chat tai, phut. Nd bao gdm thdi gian hao tdc c l djnh txd (xQc+dd) vd thdi gian thao tde hay ddi tc (thdi gian may chgy).
Thdi gian thao tde ed djnh phy thudc vdo dung ich giu vd mde do khd xuc eua dat dd ed the tra 3ang d l tinh todn. Thdi gian thao tdc thay doi co h i tinh gin dQng theo bifu thdc.
• ] lOOO.Vii,, ^gj
= 0 , 1 2 L + l i t J ^ \ - L , p h a t .
fO,12,L + !it-^-4l. •"
(6) t»
Trong iJ6: Kx - He so xOc; Kot - H# s6 hiSu qua t i c nghl#p (phg thuOc vSo tinh tr?ng cua guong va cong tie 16 chCfc); V^ - VJn t6c trung binh cua may chit tai, l<m/h; TK - Ban ldnh quy aei cua m§t b§ng khai th^c. _m: Ha - Chi§u cao cua nui da Ithai thac.m; i - Dq d6c du-dng hao, dv.
S6 6 ts can thilt phuc vg cho 1 may chit tai duoc xSc dinh theo bieu thuc:
No = u i ' ? ? ' l ^ M ) ± V t i , chile.
TcK-no (7)
Trong dd: L - Khoang cdch vgn tai bdng d td td chdn nui din nai dd tai, km; Vtbo - Vgn tie trung binh cug 0 tO, km/h; T^ - Thdi gian dd cua 0 td, phQt; Tm - Thdi gian ma no cua 0 td khi nhdn tai vd dd tai, phiit; no - S l g i u xQc day d td.
' ' ° " ' ' , giu. (8)
NoThay (8) v^o (7) ta duoc:
|,|^_1,020UV|bo) + Tj + T^
Tc,
chiec. (9) E.I<„.Yd
Trong d6: qo - Tai trpng 6 16, tin; itq - He so su- dung tai trpng; yj-Khoi iu-png rieng cua Si, t/m'.
TCr (9) qua mpt vdi biln ddi ta nhan dupc cdng thuc tinh tai trong 6 to phii hop vdi m^y chit tai:
[(120.L;v,M) + Ta+T^].Ek„.Yj
qo = , tan. (10)
Thay (5), (4) vao (2) xac dinh dupc san lu-png cua noda:
Bing 1. Swphu thuOc cOa tai tn?ng 6 to viio EviiL
(no-l).TcK.K,
D l 616 phii hpp lam vipc nhip nhang vp-i may chit tai, s l 6 to phuc vu cho 1 may chat tai it nhit la bing 2. Khi No=2, E=4 m^, Vito=20 km/h, Ta+Tm=2 phCit;
Kx=0,69; Kot=0,9; 7d=2,65 thi tai trpng 6 ta phu thupc E va L cho trong Bang 1. TCi- bilu thuc (10) ta thiy nlu s l 6 to phuc vu No=3 tai trpng o tP giam hai lan, No=4 tai trpng 6 to giam 3 lln so voi truo-ng hpp No=2. Dieu nay cho ph^p doanh nghiep mo linh hoat trong vi^c lua chpn tai trpng vd so lu-png 6 to y§u clu dam bao hoan thdnh k l hoach san lupng. Quy mo tang tai trpng cua 6 to con phg thupc vao thdi gian chu ky Idm viec cua may chit tai TCK-
Khoanq each van tai bing o to L. km Tho-i qian chu ky lam viec cua may chit tai Tck, ph Tai trpng 6 to yeu cau, tan
S6 giu xuc day 6 to n Tai tronq 6 to chon, tdn Hp so su dung tai trpng
0,5 3,0 13,54 2,0 15,0 0,90
4,0 14,62 2,0 15,0 0,97
1,0 3,0 21,6 3,0 22,0 0,98
4,0 14,62 2,0 15,0 0,97
1,6 3,0 29,79 4,0 30,0 0,99
4,0 21,9 3,0 22,0 0,99
2,0 3,0 37,9 5,0 38,0 0,99
4,0 29,2 4,0 30,0 0,97
C O N G H G H I E P I I I | 6 , S 6 « - 2 0 1 5
^ ^ L
KHOA HOC VA CONG NGH£ M 6 3. COng nghe 6 t o p h d i ho-p v d i m a y c h d t t a iCO t h l canh tranh v d i cOng n g h f khai thdc khdu theo Idp bdng diJng 0 tO phdi h o p v d i mdy c h i t tai khi d to n h f n tai d chdn nQi la cOng n g h f khai thdc khdu theo Idp bang xue c h u y f n da dO qua mdng bdng may chdt tai (MCT) hay may ui (MU).
Khi s u dunp MCT vd m d via bang hdo xoan Oc, sd vdng x o l n de n^ khdng d u y c v u o t qud 0,5-^0,6 d l cd phan s u d n doi t r l n g khdng cd d u d n g hdo dDng vdo viec bo tri mdng. Khi s d dyng MU vd m d via bdng tide d o n gian, hoge z i e - z i c thi todn bp t u y i n d u d n g hao chl d u y c b l tri d mpt ben cua s u d n nui, cOn phia ddi d i f n eua nQl d u y c dung d f bd tri mdng.
Xue dd y chdn mdng h i f u qua b a n ea la dung may xQc k i l u xdy d y n g ed c h i f u cao xQc Idn nhdt cua mdy xQc cang ldn cang tdt vi khoi l u y n g da c h u a d u y c d chdn mdng V j (m^) ty I f thugn bdc 3 v d i c h i l u cao d i n g dd d u d i chdn mdng [2].
Thdi gian ehu ky Idm v i f c cua mang IQc nay d u y c xdc dinh theo b i l u t h d c :
T=(ti+t2)=(V<,/Qc,)+(VyQoO. g i d . , (11) Trong dO: ti=(Vd/Qct) - T h d i gian may chdt tai xuc da tren tdng d l tgo nen dong dd d u d i chdn t u y i n Vd; t2=(Vd/Qgc) - T h d i gian may xQc g d u cdp xQc h i t ddng da d u d i ehan t u y i n V^; Qqt v a Qgc - Nang s u i t cua may chat tai Idm v i f c t r f n tdng vd mdy xQc g i u cdp lam v i f c d u d i chdn mang, m^/h.
o l cho cOng tdc gida hai cOng dogn lam viec cua mdng d u y c nhjp nhdng, t h d i gian ti vd tz phai bdng nhau va bdng t (ti=ti=t). T u d d :
t=(Vd/Qc,)=(Vd/Qci). g i ^ - . ( 1 2 ) T r f n CO s d (12) ta chpn d u y c dung tich gdu eua
MCT va mdy xuc g i u cdp (MXGC) theo eae b i l u thde sau ddy n l u ta chpn t h d i gian t cho t r u d c .
"^^ 60.Kx.Ko[.t ^ '
3'= 60.Kx.Ko,.t ^ ' Trong dd: Tc - T h d i gian chu ky xuc cua mdy xue tay gdu, phut.
Khi dp dyng cdng n g h f ndy t h u d n g phai ap dyng ca ngan (vi dy thdi gian lam v i f c cua ca la 6 gid).
4. Cdng nghe khai thac k h u m o c d hai nui da d u g c khai thac d d n g t h d i ndm each nhau k h o n g x a Khi d khu md cd hai nQi dd d u y c khai thac ddng thdi nam cdch nhau khOng xa (hode cdc mdm nui ndm trong m f t q u i n t h l nui) cQng ed t h l dp dyng cdng n g h f khgi thde n h y dd trinh bay y mue 3). Tuy n h i f n s y khdc nhau c o ban d ddy Id mpt mdy c h i t tai Idm cOng v i f c xuc dd d d vdo mdng eho ca hai nui, cdn mdy xQc gau cap xQc dd d chdn mdng d ea hai nQi cung chi dQng mpt mdy. Trong s o d l edng
n g h f nay cd s y di c h u y i n cua M C T v d MXGC. Khi may chat tai dang d d dd vdo mdng N°1 thi mdy xuc g i u cap dang xQc d ehan mdng N°2. K i t ttiQc viec xuc d i n g dd d chdn may N°2 va di e h u y l n d i n chdn mdng N°1 thi mdng ndy da d u y c chat ddy.
T o d n b f chu ky Idm v i f e cua mdy chdt tai se Id:
Trt=[(2Vd/Qct)+tdct]. gi^-. (15)^
C d n t h d i gian c h u kJ Idm v i f e cua MXGC 6 chdn nQi bang.
Tgc=[(2Vd/Qgc)+tdgc]. g i d . (16) Trong dd tdct vd ddgc - t h d i gian di c h u y i n cua may
chdt tai va gau edp tlnh cho mgt chu k^ Idm viec gi6'.
NO d u y c xdc djnh t r f n c o s o khoang each di ehuyen cua may chat tai v d mdy xQc gau cap t d mdng n^y d i n mang kia vd vgn t i e di c h u y i n cua chung.
Dh eho cdng v i f e d tren tang vd d u d i ehan mdng phoi h y p d u y c nhip nhdng, ndng cao thai gian s u d y n g t h i l t bj, t h d i gian chu ky Idm v i f c cua mdy c h i t tai T a v d t h a i gian chu ky ldm viec cus, mdy xQc gau cap Tgc l l y bdng nhau vd bdng: *
Tct=Tgo=Totd d d cd t h l x d c dinh nang s u i t cin t h i l t cua mdy c h i t tai cung n h u mdy xuc gdu c^p
theo cdc b i l u t h d c : . Qct=[2Vd/(To-t,ct)],ni'/gidvd J Qgc=[2Vd/(To-tdgc)], m ' / g i d . ( 1 7 ) 1 Dung tich g i u y f u c l u t u o n g d n g se Id' \
60.K,.Kot.(To-Tdc,) ^ P ^>:U:kK ^ 3 (^gj
3^= 60.K,.Kot.(To-Tdgc)
Trong d d : TCK - T h a i gian c h u ky xQc eua may xuc tai ldm v i f c tren t a n g , phQt; T c - T h d i gian chu ky xue eua mdy xQc tay g i u , phQt.
Tuy theo d i l u k i f n t h d i t i l t eua khu m d , c h l dO Idm v i f c cua m d , t r u l u y n g cua nQi d a , san luyng y f u eau vd kha n d n g trang t h i l t bj cua doanlt nghiep mo ( c d t h i f t bj) m d n g u d i ta chgn thdi gian chu ky lam v i f c To- N l u c h p n c h l d d Idm v i f c ngSy 1 ca vd t h d i gian ca Idm v i f c b i n g t h d i gian chu 1^
lam v i f e cua hai m d n g thi s a n l u o n g md eO t h l d^it d u y c y m d e eao v a gdn bang 2Vd/ca.
V d i 4 s o d l cOng n g h f trinh bdy tren day b§n canh v i f c so sdnh cdc d i l u k i f n k J thudt, n l u can can nhac v l mgt kinh t l cO t h l diJng tieu chi ehi phi quy c h u y i n d l q u y l t djnh ehpn cOng n g h f khai thdo h y p \<i cho mpt doi t u y n g ey t h l dang n g h i f n cdu: f |
C,=(CKi+E.ki), d W = > min. ^ (19)|-' Trong d d : C, - Chi phi tinh ehuyen d l thu d u y c 1 m'
da nguyen khai theo p h u a n g dn t h d i, d / m ^ CKJ- Chi phi d l khai thdc 1 m da nguyen khai theo p h u o p dn t h d i, d / m ^ E - H f so djnh m d c h i f u qua On di t u ; K, - S u i t d i u t u c o ban p h u o n g dn t h d i.D
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