762 Nghien cuu va danh gia trang thai dong hoc ctia Choong trong khoan xien djnhjiuong^ NGHIEN CUtJ VA DANH GIA TRANG THAI D Q N G HOC CUA CHOONG KHOAN TRONG KHOAN XIEN DINH Hl/OTVG Nguyin Van Giap, T[.]
762 Nghien cuu va danh gia trang thai dong hoc ctia Choong khoan xien djnhjiuong^ N G H I E N CUtJ VA D A N H GIA TRANG THAI D Q N G H O C CUA C H O O N G K H O A N T R O N G K H O A N X I E N D I N H Hl/OTVG Nguyin Van Giap, Tr^n Dinh Kien Trw&ng Dgi hpc Md - Dia chdt Hd Ndi Tran Xuan Dao XNLD Vietsovpetro TOM TAT Tir cdc sd lieu thuc te thi cdng xdy dung cdc giing khoan xiin dinh hu&ng bdng phuang phdp khoan rdto tren viing md Bgch Hd vd Rdng cua XNLD Vietsovpetro, trgng thdi ddng hgc cua chodng dugc nghien ciru bdng phuong phdp phdn tich vd tdng hgp luc tdc dung lin chodng khoan cdc diiu kiin cu thi nhdm ddnh gid, xdc dinh quy lugt chuyin ddng ciia chodng khoan qud trinh khoan xiin dinh hucmg Thdng qua bdo cdo khoa hgc ndy, nhdm tdc gid mudn di cap din phuo'ng phdp vd kit qud nghiin cim trgng thdi ddng hoc cua chodng khoan nhdm timg bu&c hgp ly hod quy trinh ldi chinh xien viec xdy dung cdc giing khoan xiin dinh hucmg TONG QUAN VE CONG TAC KHOAN XIEN DINH HUTONG Do nhirng uu diem vupt trpi ciia phuang phap khoan xien dinh huang, dupe irng dung tai hau bet cac gieng khoan them luc dia Viet Nam, cac gieng khoan xien dinh huong dupe thuc hien theo cac dang quy dao truyen th6ng nhu sau: Dang quy dao doan Quy dao doan duoc the hien Hinh Day la dang quy dao co doan thang dimg o duoi ciing nam tang san pham Theo thu tu tir tren xu6ng nhu sau: Doan thang dung tren ciing - Doan cat goc (lay goc nghieng va goc phuang vi) Doan 6n dinh goc Doan giam goc Doan thang dung duoi ciing Dang quy dao doan Quy dao doan duoc the hien Hinh Day la quy dao ma doan than gilng di vao via san pham van c6n mpt gia tri goc nghieng nhat dinh Theo thir hr tu tren xu6ng nhu sau: Doan thang dung tren cimg Doan cat goc Doan 6n dinh g6c Doan giam g6c den dp 763 Tuyen tap bao cao Hoi nghj KHCN "30 nam DSu Viet Nam: Co hoi moi, thach thuc mdi" •230 - , | L L ^ ; : i • • - - i - - - 200 230 400 380/£.00 l- 50S/9.12 SOO I 631/15.6 ; Y - 883/30 07 ; 1230 '• • ;"-4 - ; eoo '• \ A•AJSO I — -, f ' ' , -; , - :YI3OOS8.75 r T r " ^ y " i i !._._! L j^i^*??i?p„ i , j ; ; , ; 1, - t , , ; 3\,30S(Wlg.29- J ; ã ôằ13âni.25 ^_ _ 1800 -• 2000 ; >^8eiS8.30 : 2200 2300 -—i—- —-i i-— zam ; \^«(W*1«> ^ 3250 ' 14)0 X'247 BJd7jeo 2730 973/27.52 TtlO7*27J0!' 1200 bTf I 2230 \ 1000 N^* 1300 57o/3,soL L L ; ; ,J - - ] e73no.73 : : ; ; ; L775cojo._.: : ; ; : eoo : -i | t ^ ^JV-M»l 2S00 ! :'" ?5M 3000 230 230 9D0 730 100O 1230 13110 1730 200O -200 Hinh 1: Quy dao gieng khoan doan _ _ 200 400 eoo J ; ' " OC09/14 00' 900 10001200 -14001000 1900 Hinh 2: Quy doa gieng khoan doan Dang quy dao doan Theo thu tu tir tren xu6ng nhu sau: Doan thang dimg tren cimg Doan cat goc Doan 6n dinh goc Quy dao doan dupe the hien Hinh Day la quy dao ma than gilng co goc nghieng Ion va co dp doi day Ion , T 0 230/3.00: i J 338/4.70;'""';"'" ; 498/8>40; ã 710/0,00* 840/ ô | ' '• 300 230 SOO -': -i- 380/6.00 508/9,12 I 631/15.SC eoo ' • ' • ' , ' [ ' , 730 1000 1230 , l \ , 883/30 07 i : I ; : ; I VS.-.1009/J7.47 ; ;"" \ C9.50 ; : : ; VI2IOJ®3-oo; soMZjn—^ -T V.1* * 1300 ; ; ; ; ; , , -• ' , ; : : , 1200 ^ 1300 1121/0«i^; J '1380/2.70"" " • '• •iTiu/ajlo ^^ K M ' ^ ' \l99^1/2d.68 ; J L ^—f-p-.l —- ; ; ; 2100 2400 2000 2230 ^^anj37jeo i—-i—- j \ 2700 ^^B27fmJ0 3300 2730 3800 3000 ; • ; ; \i4UOMJBO 3300 -: 4200 ;_,._ 230 300 730 1000 1230 1500 1730 2000 Hinh 3: Quy dao gieng khoan doan \ f l y^S.^00/3i 5e a3ô> 3300 3230 ' V 3020^1.40: "ã;""" \ a ằ i \33iey22io -"ã;^V34eằc3ô> ; ã^g812ô8.20 3000 2300 2884^380 '' XioajaM -4- - - | - I ; J -300 300 000 7J O ' 3«BJ0 J ^ I 900 1200 1500 1800 2100 2400 2700 Hinh 4: Quy doan gieng khoan doan moi Ngoai ra, thuc te thi c6ng da dua vao ap dung them mpt dang quy dao doan loai mai c6 cau true nhu sau (Hinh 4): Doan thang dimg tren ciing Doan cat goc 764 Nghien cuu va danh gia trang thai dong hoc ciia Choong khoan xien djnhjurong^ Doan 6n dinh goc Doan lay goc ian Doan 6n dinh goc (vai goc nghieng Ion hoae than gilng nam ngang) M6i dang quy dao than gieng deu c6 nhimg uu va nhupc dilm rieng, viec lira chpn dang hay dang khae phu thupe rat Ion vao c6ng nghe - ky thuat hien c6, dieu kien dia chat va muc dieh sir dung gieng Thue te cho thay qua trinh thi e6ng eae gieng khoan xien dinh huong thi viee dam bao quy dao thuc te ciia gieng di dung quy dao thiet ke kh6ng phai luc nao eiing nhu y mu6n (Hinh 5) Tir ket qua khoan xien dinh huong eo the thay rang viec dam bao 6n dinh g6c nghieng ciia than gieng da kho, nhung viec dam bao goc phuang vi eua than gieng lai eon kho hon -3S0 •200 330 700 1050 1400 1750 • • I 375/1.3U 517/6.00 I 717/9.00\ 867/13.00 \ 1000/20.2 • ' \i320/2 ' ' A 1670/20.00: ; -400 50 -800 — vk 1970/16.00 2100 2450 -600 " -1000 '• fll"2220/14.75 " ' ; : — J600/16.00 2750/18.75 ; 2800 - -1400 3150 V l 3450/25.25 \\SeiO/23.00 \ \ 3770/20.50 \\3930/30.0C 3500 3850 ; -1200 -1000 -800 -600 -400 -200 200 W4110/46 " - - ; \ \ / 4.75 ; 38.00; ^ s 3/59.04 0/30.50 4200 4550 ; | ' i 50/26.00 4900 -350 350 700 1050 1400 1750 2100 245 Hinh 5: Quy dao thirc te va thiet ke theo hinh chieu dirng va chieu bang cua gieng khoan Voi su phat trien cua khoa hpc, hien cac hang dich vu dau tren thi gioi da dua nhieu giai phap c6ng nghe - ky thuat nham dam bao lai ehinh xien than gilng di dung huong theo quy dao thilt kl nhu cae he thong qua trinh khoan (MWD) Hien da CO he th6ng khoan lai chinh bang r6to dupe thuc hien tu dpng th6ng qua he thing chuyen dung, voi he th6ng qua trinh khoan luon dupe kiem soat qua phan mim may tinh va huong di eua cho6ng se dupe lai chinh eo chieu huong bi lech khbi quy dao Do la nhimg uu diem n6i trpi ciia cac c6ng nghe va thiet bi moi da lam eho c6ng tac lai ehinh xien tro nen nhe nhang hon voi dp chinh xac cao hon Nhung cting kh6ng thi phu nhan nhimg ban che eiia n6 nhu chi phi ban dau va bao duong cao, gia rat cao Ngoai ra, m6i truong lam viee d6i hoi kha khat khe, he th6ng lam sach dung dieh phai dat tieu chuan, hon nira sir dung eae c6ng nghe vao khu vuc m6 Bach H6 va mo R6ng Tuygn tap bao cao HQi nghj KHCN "30 nam Phu Viet Nam: Co hoi moi, thach thuc moi" 765^ cho thay kh6ng phii hop khoan tram tich Oligocen tren, voi ty trpng dung dich tir 1,50 - l,78g/cm^ ty trpng dung dich eao nen gia tri t6n hao ap suat rat Ion dpng CO day va lam cho hieu suat ciia dpng co day rat thap, nhieu truang hop la kh6ng lam viec Mpt kh6 khan ntra la khoan tang da mong nirt ne, voi cuong dp mat dung dieh Ion va dung dich c6 phan eiia chat ch6ng mat dung dich nen kh6ng eho phep dpng CO day lam viec Hon thi ntra, de ap dung va thuc hien dupe c6ng nghe moi doi h6i phai CO mpt dpi ngii chuyen gia lanh nghe Trong thuc te khoan cae khoang khoan phuc tap, kha nang gap su c6 ket, mut bp can khoan lu6n xay ra, nhat la kha nang mat bp khoan cu vai eae thiet bi gia tri hang trieu d6la a long gieng lu6n rinh rap nen ap dung e6n.g nghe moi phai bet sire can trpng qua trinh khoan Sir dung bp khoan cu truyen th6ng bang khoan r6to cat, lai va chinh xien the hien nhieu nhupc diem nhu co nhieu kho khan viec dam bao theo quy dao thiet ke, buong di eiia than gieng kho kiem soat, nhung d6i lai c6ng tac khoan rat thuan tien va don gian, gia lai rat re va kh6ng doi h6i gi ve thiet bi va bao duong Thuc te c6ng tac khoan xien dinh buong, o nhung khoang chieu sau cat tao g6c hoae chinh lai g6c phuong vi ciia than gieng thi moi phai sir dung den tu6cbin hay dpng co day co dau n6i cong, c6n cae khoang khoan tang goc, 6n dinh g6c va giam goc deu dupe thuc hien bang phuang phap khoan r6to voi bp khoan cu tuong iing De giam thieu nhiing ban che ciia phuang phap lai chinh xien truyen th6ng va nham tang dp chinh xac va kha nang dam bao Mi ehinh g6c va phuong vi eiia than gieng doi h6i phai c6 nhiing nghien cuu danh gia mpt each t6ng the ve trang thai dpng hpc ciia choong khoan, ve ban chat eiia n6 nham hoan thien va dua dupe nhtrng cau true ciia bp khoan cu phii hop cho cac khoang khoan voi nhijng muc dich cu the NGHIEN ClTU QUY LUAT H J N G CHUYEN DONG CUA CHOONG KHOAN Quy luat chuyen dong cua choong khoan bang phu'ong phap roto voi bo khoan cu giam goc Th6ng qua kit qua thuc tl eiia hon 200 gieng khoan xien dinh buong tren m6 Bach H6 va m6 R6ng, phan tich va xir ly cac s6 lieu th6ng ke ve quy dao ciia gieng khoan a nhting khoang khoan tang, giam hoae 6n dinh goc nghieng dupe thuc hien bang phuang phap khoan r6to vai bp khoan cu truyen thong, cho thay mpt hien tupng kha ro net la goc nghieng cua than gilng giam (Aa < 0) thi phuang vi cua than gieng lu6n bi lai sang phai so voi true cua than gilng (A(p > 0), cuong dp thay d6i goc phuang vi Acp lu6n bien thien va ty le thuan vai cuong dp giam goc nghieng (Aa < ) cua than gieng Quy luat duoc thi hien a hau bet cac gieng khoan c6 khoang khoan giam goc nghieng day xin dua gilng khoan 1014-MSP-10 lam vi du (Hinh va 7) [ 1, 2] Kit qua nghien cim cac s6 lieu thuc tl thi c6ng cac gieng khoan xien dinh buong, giup chiing ta dua mpt nhan dinh rang voi bp khoan cu r6to khoan khoang khoan giam goc thi su bien thien va m6i tuong quan gitra cuong dp thay d6i goc nghieng vai cuong dp thay d6i goc phuong vi ciia than gieng the hien kha ro net va co chilu huong ty le thuan vai va luon tuan thii theo mpt quy luat chung la g6c nghieng giam dan theo chieu sau thi goc phuong vi ciia than gilng eiing tang dan va chuyen dich sang phai so vai true cua than gilng Nhung ciing can phai nhin manh mpt Nghien cuu v^ danh gia trang thai dong hoc cua Choong khoan xien djnhjjujjli 766 dilm la mire dp ciia m6i tuong quan phu thupe nhieu vao ylu t6 hinh hpc ciia than gilng, dilu kien dia chat cu the va cau tnic ciia bp khoan cu, v.v 300 600 900 1200 1500 1800 2100 Ll 325/26.75 1,1475/25.00 1675/23.50 1825/22.25 1975/20.751 ,2125/19.50 275/17.50' ' 425/16.00 r 1 \ r r ' : 1 1 1 630*Vifel>S -30 : -180 2400 _ ; ; - -L - J^-i??^sio 75, i _ ; L - -1- -270 2725rt7.25 i\;i.»SS2*-OT_:_ _._ j ^ i _ _ _ i _ _ L _ _ J 2700 ;• ; ^ \ ^soS^e.so ' ; ; '\K7S\ie.75 ^^0\1|7.00 ' 1 •380 3000 13225^5.50 3375^4.00 3300 3584/0.00 3700/7.25 3850/5"25 3600 3900 -450 -340 I I I I I I I I I I I I I I I I I I I I si5o\ffoi^Nl 3i2m,i''-J' -630 4080/6.50•720 4200 1 90 180 270 ' I I 940 630 1 720 610 •810 4500 -300 300 600 360 450 900 1200 1500 1800 Hinh 6: Quy dao thyc te v^ thiet ke theo hinh chieu dirng v^ chieu b^ng cua gieng khoan 1014-MSP-lO Cudng d6 thay ddi goc nghieng, dd/lOm Hinh 7: Bieu quan he gifra cu'O'ng thay doi goc nghieng v6i phuo'ng vj than gieng (1014-MSP-lO) o- khoang khoan 1950 - 2375m Quy luat chuyen dong ciia choong khoan bang phu'ong phap roto voi bo khoan cu tang hoae on dinh goc Qua phan tich ket qua khoan a nhimg khoang khoan hau bet cac gilng cho thay goc nghieng cua than gilng co chilu huong tang len theo chieu sau gieng thi goc phuang vi ciia than gilng cung c6 it nhilu thay d6i theo mpt quy luat nhat dinh Sir thay d6i hit siic nhay cam va dl bi triet tieu hoae lam cho phan nao sai lech quy luat chung 767 Tuyin tap bao cao HQi nghj KHCN "30 nam Dau Viet Nam: Co' hoi moi, th^ch thuc moi" cac ylu t6 ngoai canh, nhung su biin thien eua no vin co the nhan biet qua cae than gilng da khoan, tiiy theo miic dp gia tang ciia goc nghieng ma goc phuang vi thay d6i nhilu hay it tire la ro net hay kh6ng ro net Co thi thay goc nghieng tang (Aa > 0) thi than gilng eo ehilu huong Mi sang trai hoae 6n dinh so voi true cua than gieng (Acp < 0) Kit qua thuc tl thi hien ro quy luat a hau bet cac gieng khoan c6 khoang khoan tang hoae 6n dinh goc nghieng Xin lay gilng khoan 102-RP-l lam vi du (Hinh va 9) [1, 2] Hau hit cae gilng khoan vai khoang khoan 6n dinh goc (dang quy dao doan) ma a khoang khoan nlu thue hien khoan ket hgp su tang goc nghieng voi cuong dp thay d6i g6c nh6 0,05 - 0,1 dp/lOm thi kha nang se dam bao duoc sir 6n dinh huong di eiia than gieng ma thuc te da chiing minh cac gieng 101, 103 tren gian RP-1, nhung cuong dp thay d6i goc nghieng lan ban 0,1 dp/lOm thi chieu buong than gieng bi lai sang trai nhieu hon so voi true cua than gieng Sir tuong quan gitra cuong dp thay d6i goc nghieng lu6n theo mpt ty le nhat dinh voi cuong dp thay d6i goc phuong vi ciia than gieng va tuan theo mpt quy luat ro rang Aa > thi Acp < Nhung sir ty le c6n phu thuoc vao nhieu yeu t6 ngoai canh tac dpng vao nhu che dp c6ng nghe, dp khoan va tinh chat co - ly cua dat da, goc nghieng tire thai cua than gieng, cau triic cua bp khoan cu, v.v Ciing chinh nhting tuong tac da phan nao lam cho quy luat nhieu liic, nhieu noi phan nao hi sai lech Nhung xem xet mpt each t6ng the tat ca cac truong hop cho phep dua ket luan rang choong khoan se dupe tu dieu chinh co sir ket hop gitra hai gia tri ciia cuong dp thay d6i goc nghieng va cuong dp thay d6i goc phuang vi cua than gieng 800 700 SOO SOO 400 /f^ Uajsj 300 5»jj 200 ^~,._JiioB*>-.^.5< 100 -100 ; i •ii -2O0 ^~ -1300 -1200 -1100 -1000 -300 -800 -TOO -600 , -200 200 400 600 -500 400 -300 -200 -100 800 10t^r~-ir Cucmg d6 thay ddi goc nghieng, d6/10m Hinh 9: Bieu quan he gifra cuong dg thay doi goc nghieng voi phuong vi than gieng (102-RP-l) a khoang khoan 1275-2190m NGHIEN c u t ! VA PHAN TICH CO CHE TU-ONG TAC LU^C CHOONG KHOAN TRONG QUA TRINH PHA HUY DAT DA Phan tich co* che phan bo lyc tren choong va hu'ong chuyen dong (Atp) cua no tru-ong hop tang goc nghieng (Aa > 0) hoae 6n dinh goc (Aa = 0) Bp khoan cu sir diing khoan r6to cac khoang khoan tang hoae 6n dinh goc duoc minh boa Hinh 10 tren mpt doan than gieng da t6n tai mpt gia tri g6c nghieng nhat dinh Cac lire dupe phan b6 tren eiing mpt mat phang, a day eo thi thay nlu F3 > 0, dilu c6 nghia la khoang khoan dang tang goc nghieng theo chilu sau (Aa > 0), truang hpp ngupe lai, F3 < tire la khoang khoan se giam goc nghieng theo chilu sau (Aa < 0) PTinh 10 bilu dien sir phan b6 lire a cac phan ciia bp khoan cu va phan lire t6n tai tren choong khoan theo thilt dien thang dimg De nghien ciiu va phan tieh t6ng hop lire tuong tac tren choong khoan va huong dich chuyen ciia no can thilt phan tich lire tren thilt dien ngang a day gilng [3, 5] Hinh 10: Phan bo lyc o* cac phan cua bo khoan cu tren mat phSng Tron d6: 1) Choong khoan; 2) Cln nang; 3) Dinh tam; P) Trpng lupng ciia thilt bi; F) Phan lire; g) Thanh phan lire theo chilu true cua bp khoan cu; f) Thanh phan lire theo chieu vu6ng goc vai gilng; G) Tai trpng len eho6ng; co) Van t6c quay can khoan Tuygn tap bao cao Hoi nghj KHCN "30 nam Pau Viet Nam: Co' hoi moi, thach thuc moi" Mat cat ngang be mat choong 769 Mat cat ngang day gieng khoan Hinh 11: Tiet dien ngang be mat day gieng va choong khoan tru'ong hop tang goc nghieng Hinh 11 minh hpa su phan b6 lire truang hpp tang goc nghieng Aa > Trong truang hgp eo the thay, theo ly thuyet duong kinh cho6ng lu6n bang voi duong kinh gieng khoan, truang hgp F > (Aa > 0) nen chobng khoan lu6n co xu huong tiep xiic true tiep len be mat phia tren voi gieng khoan Duoi tac dpng cua choong khoan, dat da bj pha vo ea phan thiet dien ciia day gieng va phan tiep xiic phia tren ciia chobng voi than gieng theo thai gian thuc Trong do: F - T6ng hpp lire tren cho6ng theo mat cat dimg; Fco - Phan luc tai diem tiep xiic gitra choong va gieng phia tren ciia than gieng tao bai van t6c quay co ciia can khoan; co - Van t6c quay ciia can khoan; Fcp - T6ng hpp lire gitra Fo3 va F; Acp Cuong dp thay d6i goc phucmg vi eiia than gieng Duoi tae dung cua cac lire G, F va van t6e quay can khoan co, ket hpp voi cau tao ciia choong khoan ba chop xoay, be mat ngoai ciia cae eh6p xoay ian lugt tiep xuc voi gieng phia tren ciia than gieng 6 thu IV ciia thiet dien (Hinh 11) vai mpt lire F va phan lire Fco sinh boi he qua ciia van t6c quay can co be mat ngoai ciia cho6ng tiep xiic voi gieng khoan, t6ng hgp cua phan luc Fco Ic^n nhat tai diem O Tir ket qua nay, duoi su tuong tac giiia luc F va Fco se eho t6ng hpp lire Fcp Day chinh la gia tri lam thay d6i buong di ciia choong khoan (Acp) Duoi tae dpng ciia luc Fcp, ket qua la khoang khoan voi gia tri cuong dp thay d6i goc nghieng lan hon khong (Aa > 0) thi huong huyen dpng ciia cho6ng khoan eo chieu huong dich chuyen ve cung thir IV ciia thiet dien day gieng, tire la phuong vi ciia than gieng se thay d6i theo chieu huong sang ben trai so vai true ciia than gilng Gia tri Acp phu thupe rat nhieu vao m6i truang lam viec cua choong nhu tinh chat co ly ciia dat da, eae th6ng s6 che dp c6ng nghe, g6e nghieng thuc ciia than gilng tai thoi dilm xem xet, cau triie eiia bp khoa cu v.v [5] 770 Nghien cuu va danh gia trang thai dong hoc ciia Choong khoan xien djnhjurojlg^ Trong thuc te gia tri Fcp dao dpng bet sire nhay cam Fcp la he qua ciia F va van t6c quay can khoan co, ma gia tri F dupe hinh tir cau tao co tinh toan eiia bp khoan cu tir sir phan b6 trpng luc cua cac phan eiia bp khoan cu va khoang each giua eae diem ty (dinh tam) len gilng khoan Nhung gia tri F lai dl dang bi triet tieu hoae eong huang boi cac tae nhan nhu mirc dp 6n dinh cua gieng, tai trpng len choong, su bat d6ng nhat eua dat da khoan qua, v.v timg dieu kien va m6i truong cu the [4, 5] Ciing chinh tir he qua ma s6 lieu thue te thu nhan dupe cho thiy c6 mpt s6 truong hpp da nam ngoai quy luat chung va day ciing la dieu de hieu Phan tich cc che phan bo lyc tren choong va hu-ong chuyen dong (Acp) cua no tru-ong hop giam g6c nghieng (Aa < 0) Cting tuong tu, khoang khoan giam goc, tucmg img voi cau true ciia bp khoan cu ting hpp lire theo phuong thang dimg tai thiet dien ngang ciia choong la luc F eo chieu di xu6ng (ngupe voi truong hgp tang goc) (Hinh 12) Duoi tac dung eiia lire F va van t6c quay can khoan co be mat ngoai ciia than canh choong va chop xoay ian lugt tiep xiic true tiep voi be mat gieng a cung thir II r6i mai chuyen sang cung thii III (Hinh 12), co the thay t6ng hgp phan lire Fco Icin nhat la diem O co chieu nguge vai chieu quay ciia can khoan Ket hgp lire gitra F va Fco cho gia tri ciia Fcp, day ehinh la tac nhan lam eho hu(3ng chuyen dgng ciia cho6ng dieh chuyen sang ben phai so voi true ciia than gieng Ket qua la than gieng khoan lu6n eo chieu hucmg chuyen dich sang phai vai phuang vi tang dan theo chieu sau cua gieng khoan khoang khoan eo sir thay d6i goc nghieng theo chieu hucmg giam dan Mat cat ngang be mat choong khoan Mat cat ngang day gieng khoan Hinh 12: Thiet dien ngang be mat day gieng va choong khoan tru-ong hop giam goc nghieng Trong d6: F - T6ng hgp lire tren choong theo mat cat dimg; Fco - Phan lire tai dilm tiep xiie gitra cho6ng va gilng phia duai eua than gieng tao boi van tie quay Tuygn tap bao cao Hoi nghj KHCN "30 nam D^u Viet Nam: Co' hoi moi, thach thuc moi" 771 CO ciia can khoan; oi - Van tie quay cua can khoan; Fcp - T6ng hop lire gitra Fco \ a F: Acp Cuong dp thay d6i goc phuong vi cua than gieng Tir kit qua phan tich tren cho phep dua nhan dinh la qua trinh khoan cac gieng xien dinh hucing, goc nghieng ciia than gieng giam dan theo chieu sau (Aa < 0) lu6n keo theo sir thay d6i goc phuong vi eiia than gieng va lam cho than gieng chuyen buong sang phai so voi true eiia than gieng, tire la tuan thii theo mpt quy luat ma cuong dp thay d6i goc nghieng Aa < thi gia tri cuong dp thay d6i goc phuong vi eiia than gieng Acp > M6i tuong quan dupe the hien kha cu the quy dao than gieng ciia cac gieng khoan co doan giam goc nghieng, dieu het sire de hieu co che can bang va tuong tac lire dupe hinh trpng lire ciia cac phan ciia bp khoan cu Mat kbac, chieu vecto ciia lire F cimg chieu voi trpng lire (P) nen gia tri eiia lire F lu6n t6n tai mac dii cac dieu kien ngoai canh eo thay d6i va sir t6n tai eiia lire F lai lu6n nam m6i truang cpng buong boi trpng luc ciia cae phan rieng biet cua bp khoan cu Ket hop voi van t6c quay ciia cho6ng co nen gia tri cua t6ng hgp lire Fcp lu6n Icin hon (Fcp > 0) va ket qua la gia tri cuong thay d6i goc phuong vi cua than gieng lu6n Icm hon (Acp > 0) Thue te qua trinh khoan cae gieng xien dinh buong thi su bien thien ciia gia tri Acp c6n phu thupe vao cac gia tri Aa va goc nghieng tiie thoi ciia than gieng, che dp c6ng nghe khoan va dieu kien cu the ciia dat da khoan qua KET LUAN Ket qua nghien ciiu va phan tich th6ng ke cac s6 lieu thue te eiia hon 200 gieng khoan xien dinh hucmg tren mo Bach Ho va m6 R6ng, cho phep dua mpt s6 ket luan sau: • Trong cac khoang khoan bang phuong phap r6to a cac gieng xien va dinh hucmg, suthay d6i gia tri Aa co m6i tuong quan true tiep den gia tri cuong dp thay d6i goc phuong vi ciia than gieng (Acp) theo mpt quy luat nhat dinh: • Khi gia trj goc nghieng ciia than gieng giam dan theo chieu sau gieng khoan thi phuang vj ciia than gieng co xu hucmg chuyen dich sang ben phai so voi true ciia than gilng • Khi gia tri goc nghieng ciia than gieng tang dan theo chieu sau gieng khoan thi phuong vi ciia than gieng c6 xu huong chuyen dich sang ben trai so voi true eiia than gilng • M6i quan he gitra gia tri Aa va Acp qua trinh khoan xien va dinh hucmg dugc hinh tren co che tuong tac va can bang lire • M6i quan he gitra gia tri Aa va Acp bi rang huge va anh huong true tiep bai m6i truong va dieu kien lam viec cua choong khoan long gieng nhu cae che dp e6ng nghe, dia chat va dia tang, cau tnic va kich thuoc thuc ciia bp khoan cu, gia tri goc nghieng tire thai ciia than gieng, ciing nhu gia tri cuong dp thay d6i goc nghieng tire thoi eua than gieng, v.v 772 Nghien cuu va danh gia trang thai dong hoc cua Choona trono khoan xien djnh huong TAI LIEU THAM KHAO X Nguyin Ngpc Kilng 1996 Thdng ki hoc nghien cim khoa hoc NXB Giao due HaN6i, tr 203-232 Tran Xuan Dao 1999 Cdc nguyen ly hiin dgi phdn tich vd thiet ki cdc chi tieu khoan giing NXB Vting Tau, tr 35 - 41 {tiing Nga) A.KH Mirzadzanzade, S.A Chirin-Zade, 1986 Ndng cao hidi quo vd chdt hrang khoan cdc giing khoan sdu NXB HE FlPA Matxcova, tr 241 - 250 {tieng Nga) M.L Blanc, 1990 Bin vimg vd khu vuc hoc ddng hoc hdn logn NXB MSNMO, Matxeava, tr - 26, 95 - 101 {tieng Nga) N.G Grigulexki, V.T Lukianov, 1990 Thilt kl bp khoan cu NXB HEOPA Matxeava, tr 127 - 155 {tiingNga) ... gieng khoan c6 khoang khoan tang hoae 6n dinh goc nghieng Xin lay gilng khoan 102-RP-l lam vi du (Hinh va 9) [1, 2] Hau hit cae gilng khoan vai khoang khoan 6n dinh goc (dang quy dao doan) ma a khoang... mpt dpi ngii chuyen gia lanh nghe Trong thuc te khoan cae khoang khoan phuc tap, kha nang gap su c6 ket, mut bp can khoan lu6n xay ra, nhat la kha nang mat bp khoan cu vai eae thiet bi gia tri... bet cac gieng khoan c6 khoang khoan giam goc nghieng day xin dua gilng khoan 1014-MSP-10 lam vi du (Hinh va 7) [ 1, 2] Kit qua nghien cim cac s6 lieu thuc tl thi c6ng cac gieng khoan xien dinh