李亞南于占淼
1.中原石油工程有限公司鉆井工程技術(shù)研究院;2.中原石油工程有限公司鉆井二公司
涪陵頁(yè)巖氣田二期水平井鉆井防碰繞障技術(shù)
李亞南1于占淼2
1.中原石油工程有限公司鉆井工程技術(shù)研究院;2.中原石油工程有限公司鉆井二公司
涪陵頁(yè)巖氣田二期處于油藏邊緣地帶,地層傾角大、斷層多。由于儲(chǔ)層埋藏深,設(shè)計(jì)直井段長(zhǎng),防斜打直問(wèn)題突出;為提高采收率并降低鉆探成本,二期工程繼續(xù)采用井工廠模式開(kāi)發(fā),但與一期相比,平臺(tái)布井?dāng)?shù)量增加,井口距離小,防碰繞障難題亟待解決。以焦頁(yè)81-1HF井為例,撰寫(xiě)了現(xiàn)場(chǎng)水平井防碰施工注意事項(xiàng);結(jié)合同平臺(tái)井組井史資料,優(yōu)化設(shè)計(jì)了焦頁(yè)81-1HF井身剖面;模擬鄰井防碰數(shù)據(jù),確定了防碰重點(diǎn)井位、井段,制定了防碰技術(shù)方案及定向施工措施,優(yōu)選鉆頭、鉆具組合,避免鄰井防碰,降低作業(yè)風(fēng)險(xiǎn)?,F(xiàn)場(chǎng)應(yīng)用表明,同平臺(tái)7口水平井防碰繞障成功,井眼軌跡光滑,準(zhǔn)確中靶,為下套管及固井施工奠定了基礎(chǔ),為涪陵二期叢式水平井防碰繞障施工提供了借鑒。
頁(yè)巖氣;工廠化鉆井; 水平井; 防碰繞障; 軌跡控制;涪陵
涪陵頁(yè)巖氣田二期產(chǎn)建區(qū)劃分為江東、平橋、白濤等5個(gè)開(kāi)發(fā)區(qū)塊,其中江東、平橋區(qū)塊試氣效果最好,作為重點(diǎn)開(kāi)發(fā)區(qū)。但與一期產(chǎn)建區(qū)相比,二期地處油藏邊緣帶、地層高陡、斷層發(fā)育、儲(chǔ)層埋藏加深、單塊有利氣藏面積小,地質(zhì)情況復(fù)雜,因此為提高鉆井效率,降低施工成本,采用井工廠叢式水平井開(kāi)發(fā)模式,單平臺(tái)布井密度高,井口間距小,導(dǎo)致同平臺(tái)井組及相鄰平臺(tái)井井間防碰問(wèn)題異常突出,屬于多井防碰繞障,一旦施工設(shè)計(jì)方案及防碰技術(shù)不合理,易造成鄰井相碰事故[1]。文中以焦頁(yè)81-1HF井為例,分析了涪陵頁(yè)巖氣田二期叢式水平井現(xiàn)場(chǎng)施工技術(shù)難點(diǎn),制定了井眼軌跡控制及防碰技術(shù)方案和施工措施,保證井眼軌跡質(zhì)量,實(shí)現(xiàn)井間高效防碰,為涪陵二期叢式水平井多井防碰繞障提供借鑒。
Summary of Well Jiaoye 81-1HF
焦頁(yè)81平臺(tái)位于川東南涪陵區(qū)中部涪陵頁(yè)巖氣田二期江東區(qū)塊,地處重慶市涪陵區(qū)羅云鄉(xiāng)。地層構(gòu)造位置川東高陡褶皺帶萬(wàn)縣復(fù)向斜天臺(tái)場(chǎng)斷鼻,目的層上奧陶統(tǒng)五峰組—下志留統(tǒng)龍馬溪組下部頁(yè)巖氣層段。平臺(tái)上部署了焦頁(yè)81-2HF等7口大位移水平井,采用井工廠開(kāi)發(fā)模式,但布井方式由一期常規(guī)型布井方式轉(zhuǎn)為魚(yú)鉤型布井。其中焦頁(yè)81-IHF井是該平臺(tái)上最后施工的一口井,設(shè)計(jì)井深5060 m,最大井斜65.52°,方位0°,水平段長(zhǎng)1648.18 m,靶前距567.36 m,入靶垂深3 166 m,靶區(qū)窗口上下5 m、左右10 m,面臨著6口同平臺(tái)井防碰繞障問(wèn)題,施工難度大。該平臺(tái)井組水平投影見(jiàn)圖1。
圖1 焦頁(yè)81平臺(tái)井組水平投影圖Fig.1 Horizontal projection of well group on Jiaoye 81 flat
Construction difficulties
(1)地層傾角大、巖性復(fù)雜。焦頁(yè)81平臺(tái)位于萬(wàn)縣復(fù)向斜天臺(tái)場(chǎng)斷鼻,屬于油藏邊界帶,地層傾角大(20°~30°)、變化多;龍?zhí)督M地層含硅質(zhì)灰?guī)r夾泥巖,易蹩跳鉆,鉆速時(shí)快時(shí)慢,定向工具面不穩(wěn),井斜控制困難,鉆進(jìn)過(guò)程中定向頻繁[2]。
(2)鄰井多、間距小。焦頁(yè)81號(hào)平臺(tái)共有7口大位移水平井,南北平臺(tái)內(nèi)井口間距等間距排列,井口間距10 m,其中焦頁(yè)81-2、7、6、5HF 4口井成“L”型排列,位于南半平臺(tái);焦頁(yè)81-1、3、4HF 3口井成一字排列,位于北半平臺(tái),焦頁(yè)81-4HF井與焦頁(yè)81-1HF井井口間距最近。焦頁(yè)81平臺(tái)井位布局見(jiàn)圖2。
圖2 焦頁(yè)81平臺(tái)井位布局Fig.2 Well location arrangement of Jiaoye 81 pad
(3)按照鉆機(jī)整拖方向開(kāi)展鉆井施工。焦頁(yè)81平臺(tái)南北平臺(tái)由兩支鉆井隊(duì)承鉆,均采用鉆機(jī)整拖方式施行導(dǎo)軌平移井架,由于現(xiàn)場(chǎng)施工中鉆機(jī)整拖方向的鉆井井序問(wèn)題,導(dǎo)致沒(méi)有優(yōu)先鉆水平位移大、造斜點(diǎn)淺的井,增加了井間防碰施工難度[3]。
(4)直井段長(zhǎng)。涪陵頁(yè)巖氣田二期儲(chǔ)層埋藏垂深3 200~3 800 m,井身剖面直井段長(zhǎng)1 800~2 400 m,設(shè)計(jì)要求直井段1 000 m內(nèi)全角變化率小于1(°)/30 m,1 000 m至造斜點(diǎn)全角變化率控制在1.25(°)/30 m,防斜打直難度大。
(5)隨鉆測(cè)量?jī)x器誤差。儀器測(cè)量誤差及測(cè)量數(shù)據(jù)滯后直接影響井眼軌跡控制,焦頁(yè)81平臺(tái)使用隨鉆測(cè)斜儀器,誤差范圍方位角±1.5°,井斜角±0.1°,磁性工具面角±1.5°,重力工具面角±1.5°。
Construction preparation
3.1 總體技術(shù)方案
Construction scheme
(1)明確井場(chǎng)地理位置,確定周邊鄰井?dāng)?shù)量,明確防碰井位。根據(jù)防碰井實(shí)鉆井眼軌跡數(shù)據(jù),確認(rèn)防碰井井口坐標(biāo)、磁偏角、電測(cè)連斜和多點(diǎn)數(shù)據(jù),保證電測(cè)數(shù)據(jù)與隨鉆數(shù)據(jù)的一致性,統(tǒng)一方位數(shù)據(jù)、統(tǒng)一地磁模型[4],確保防碰設(shè)計(jì)準(zhǔn)確指導(dǎo)現(xiàn)場(chǎng)施工。
(2)優(yōu)選井眼軌跡防碰掃描方法。防碰掃描方法主要有最小距離掃描法、水平面掃描法、法面掃描法3種方法,其中最小距離法可計(jì)算井眼軌跡空間最小距離,反映鄰井三維空間距離、井斜關(guān)系。
(3)模擬計(jì)算鄰井空間防碰最近距離,確定防碰繞障重點(diǎn)、難點(diǎn)井位及井段,優(yōu)選防碰繞障技術(shù),制定繞障施工方案。
(4)施工中嚴(yán)密監(jiān)測(cè)井斜數(shù)據(jù)變化。應(yīng)用的隨鉆儀器,測(cè)點(diǎn)距鉆頭位置距離16~19 m,測(cè)斜數(shù)據(jù)有延遲,在防碰重點(diǎn)井段施工時(shí),依據(jù)已鉆井眼變化規(guī)律預(yù)測(cè)井底數(shù)據(jù),實(shí)時(shí)分析防碰數(shù)據(jù)??紤]測(cè)斜儀誤差,修正防碰模擬數(shù)據(jù),指導(dǎo)現(xiàn)場(chǎng)施工。
(5)鄰井防碰間距縮小時(shí),及時(shí)采取加密測(cè)量,勤模擬多分析,發(fā)現(xiàn)問(wèn)題及時(shí)定向調(diào)整;測(cè)量井斜數(shù)據(jù)時(shí),認(rèn)真觀察磁場(chǎng)強(qiáng)度數(shù)據(jù)變化情況,辨識(shí)、判斷有無(wú)鄰井套管磁場(chǎng)干擾。
3.2 分井段技術(shù)方案
Technical scheme of separate well section
3.2.1 一開(kāi)直井段 一開(kāi)采用“減震+扶正”技術(shù),確保直井段防斜打直,提高機(jī)械鉆速。工程設(shè)計(jì)要求一開(kāi)直井段位移≤5 m,全角變化率1(°)/30 m。
3.2.2 二開(kāi)井段 針對(duì)焦頁(yè)81-1HF井井斜控制難、防碰井?dāng)?shù)多、施工難度大的問(wèn)題,優(yōu)化造斜點(diǎn)位置,采取前期造側(cè)負(fù)向位移方法繞障,減少同一防碰掃描區(qū)域內(nèi)防碰井?dāng)?shù)量,降低防碰風(fēng)險(xiǎn)。
焦頁(yè)81-1HF井與6口鄰井進(jìn)行防碰,模擬防碰掃描數(shù)據(jù),焦頁(yè)81-3、4HF井是重點(diǎn)防碰井位,其中焦頁(yè)81-4HF井防碰最小中心距離4.23 m、最近橢圓距離僅0.95 m,分離系數(shù)1.291,井眼相碰風(fēng)險(xiǎn)高,詳細(xì)數(shù)據(jù)見(jiàn)表1,防碰分離系數(shù)見(jiàn)圖3。
表1 二開(kāi)防碰模擬數(shù)據(jù)Table 1 Anti-collision simulation data of the second spudding
為降低防碰風(fēng)險(xiǎn),并保證儲(chǔ)層鉆遇率,二開(kāi)重點(diǎn)防碰段井眼軌跡剖面優(yōu)化設(shè)計(jì)為“微增-增斜扭方位-穩(wěn)斜”,造斜點(diǎn)上移至750 m。750~800 m以全角變化率3(°)/100 m進(jìn)行定向施工,井斜增至1.5°,扭方位到130°;800~1 600 m以全角變化率1(°)/100 m鉆進(jìn),增斜穩(wěn)方位,井斜增至10°,方位130°。以方位130°造側(cè)負(fù)向位移,減少同一區(qū)域段內(nèi)防碰井?dāng)?shù)量,降低防碰風(fēng)險(xiǎn);1 600~1 950 m,增斜扭方位,井斜增至24.32°,方位由130°扭到268.81°;1950 m穩(wěn)斜穩(wěn)方位至二開(kāi)中完。
圖3 防碰掃描分離系數(shù)Fig.3 Anti-collision scanning separation coefficient
3D collision avoidance and obstacle bypass technology
4.1 一開(kāi)直井段
Vertical hole section during the first spudding
(1)鉆具組合:?406.4 mm牙輪鉆頭+ ?244mm單彎螺桿(0.5°,?398 mm扶正器)×1根+?390 mm扶正器×1根+?228.6 mm鉆鋌×1根+?203 mm無(wú)磁鉆鋌+?203 mm鉆鋌×4根+?229 mm減震器+? 139.7 mm加重鉆桿×20根+?139.7 mm鉆桿。
(2)一開(kāi)70~711 m直井段復(fù)合鉆進(jìn),每百米吊測(cè)一次,若井斜超過(guò)設(shè)計(jì)要求,采用小鉆壓吊打鉆進(jìn)。一開(kāi)完鉆,使用多點(diǎn)測(cè)斜儀器測(cè)量井斜方位數(shù)據(jù)。
4.2 二開(kāi)防碰控制技術(shù)
Anti-collision technology of the second spudding
4.2.1 微增段 微增段主要與焦頁(yè)81-3HF、焦頁(yè)81-4HF井防碰,要求全角變化率較小,采用“小彎角螺桿+扶正器”技術(shù)。
(1)鉆具組合:?311.2 mm PDC鉆頭+ ?216 mm單彎螺桿(1°,?305 mm扶正器)×1根+ ?300 mm扶正器×1根+浮閥+ ?203 mm無(wú)磁鉆鋌×1根+?203 mm無(wú)磁懸掛×1根+ ?203 mm鉆鋌×3根+?139.7 mm加重鉆桿×20根+ ?139.7 mm鉆桿。
(2)復(fù)合鉆進(jìn)與滑動(dòng)鉆進(jìn)相結(jié)合,滑動(dòng)鉆進(jìn)控制井斜微增,全角變化率控制為1~2(°)/100 m,方位120~140°,滑動(dòng)鉆進(jìn)走側(cè)負(fù)方向位移,此段防碰井?dāng)?shù)量由6口減到2口,減少防碰繞障的同時(shí)保證井眼光滑。
4.2.2 增斜扭方位段 (1)鉆具組合:?311.2 mm PDC鉆頭+ ?216 mm單彎螺桿(1.25°,?305 mm扶正器)×1根+浮閥+ ?203mm無(wú)磁鉆鋌×1根+?203 mm無(wú)磁懸掛×1根+ ?203 mm鉆鋌×3根+ ?139.7 mm加重鉆桿×20根+ ?139.7 mm鉆桿。(2)井深1 600~1 950 m以全角變化率15(°)/100 m開(kāi)始增斜扭方位,井斜增至24.32°,扭方位增至286.81°,在井深1 770 m與焦頁(yè)81-5HF井距離最近,采取定向增斜、扭方位,1 794 m后井段逐漸遠(yuǎn)離,與此井再無(wú)防碰風(fēng)險(xiǎn)。
4.2.3 穩(wěn)斜段 (1)鉆具組合:?311.2 mm PDC鉆頭+?216 mm單彎螺桿(1°,?305 mm扶正器)×1根+?285 mm扶正器×1根+浮閥+ ?203 mm無(wú)磁鉆鋌×1根+?203 mm無(wú)磁懸掛×1根+ ?203mm鉆鋌×3根+?139.7 mm加重鉆桿×20根+ ?139.7 mm鉆桿。(2)由于模擬焦頁(yè)81-1HF井穩(wěn)斜段與鄰井焦頁(yè)81-2、6、7HF井防碰,井深2 040 m,距離焦頁(yè)81-6HF井最近,分離系數(shù)4.791;井深2 070 m,距離焦頁(yè)81-2井最近,分離系數(shù)7.827;井深2 077.94 m,距離焦頁(yè)81-7井最近,分離系數(shù)3.356,因此施工風(fēng)險(xiǎn)高,密切監(jiān)視與鄰井的防碰距離變化,分析已鉆井眼井斜微增、方位微降的規(guī)律基礎(chǔ)上,提前定向施工,避免了井間碰撞可能。在井深2 180 m,井斜23.9°,方位286.82°,與最近焦頁(yè)81-7HF井,中心距離55.5 m,橢圓距離47 m,分離系數(shù)提升至6.228,消除了井間碰撞風(fēng)險(xiǎn),全井防碰施工結(jié)束,防碰繞障成功。
4.3 現(xiàn)場(chǎng)應(yīng)用效果
Field application
焦頁(yè)81-1HF井通過(guò)應(yīng)用防碰繞障控制技術(shù),與6口鄰井防碰成功,重點(diǎn)防碰井位井間距離和相對(duì)方位變化見(jiàn)圖4。
圖4 井間距離和相對(duì)方位變化Fig.4 Change of interwell distance and relative azimuth
焦頁(yè)81-1HF井一開(kāi)井段全角變化率小于1(°)/30 m,符合設(shè)計(jì)要求;二開(kāi)采用“小彎角螺桿+扶正器”技術(shù),降低了滑動(dòng)鉆進(jìn)比例,提高機(jī)械效率的同時(shí)保證了軌跡的平滑,緩解了后續(xù)施工難度。
Conclusions and cognitions
(1)涪陵頁(yè)巖氣田二期產(chǎn)建區(qū)地層結(jié)構(gòu)較一期復(fù)雜多變,采用井工廠叢式水平井開(kāi)發(fā)模式,需結(jié)合工程設(shè)計(jì)整體規(guī)劃鉆機(jī)整拖井序,制定總體設(shè)計(jì)方案,減少防碰控制不利因素。
(2)一開(kāi)直井段采用“減震+扶正”防斜打直技術(shù),避免了井斜過(guò)大,為后續(xù)防碰繞障施工奠定基礎(chǔ),同時(shí)提高了機(jī)械鉆速。
(3)優(yōu)化了二開(kāi)重點(diǎn)防碰井段井身剖面,應(yīng)用最小距離防碰掃描法,確定了重點(diǎn)防碰井位;二開(kāi)“微增段-增斜扭方位段-穩(wěn)斜段”重點(diǎn)防碰井段,優(yōu)化了造斜點(diǎn)位置,采用走側(cè)負(fù)向位移繞障井眼軌跡控制技術(shù)成功實(shí)現(xiàn)了井間防碰繞障。
(4)叢式井組多井防碰施工,獲得準(zhǔn)確的鄰井實(shí)鉆數(shù)據(jù)、分析預(yù)測(cè)井眼軌跡走向、精確判斷有無(wú)鄰井套管磁干擾是實(shí)現(xiàn)安全優(yōu)快防碰鉆井的關(guān)鍵。
References:
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[2]王霞.連平6-4井防碰繞障技術(shù)研究[J].中國(guó)石油和化工標(biāo)準(zhǔn)與質(zhì)量,2014(10):79.WANG Xia.Lian Ping6-4 Well anti-collision and barrier by-passing technology research[J].China Petroleum and Chemical Standard and Quality,2014(10): 79.
[3]劉曉艷,施亞楠,李培麗.叢式井組整體防碰與鉆井順序優(yōu)化技術(shù)及應(yīng)用[J].石油鉆采工藝,2012,34(2):9-12.LIU Xiaoyan,SHI Ya’nan,LI Peili.Techniques of cluster well general anti-collision and drilling sequence optimization[J].Oil Drilling & Production Technology,2012,34(2): 9-12.
[4]王萬(wàn)慶,田逢軍.長(zhǎng)慶馬嶺油田水平井鉆井防碰繞障技術(shù)[J].石油鉆采工藝,2009,31(2): 35-38.WANG Wanqing,TIAN Fengjun.The anti-collision and barrier-bypassing technology of horizontal well drilling in Changqing Maling Oilfield[J].Oil Drilling &Production Technology,2009,31(2): 35-38.
(修改稿收到日期 2017-02-08)
〔編輯 薛改珍〕
Collision avoidance and obstacle bypass technology for horizontal wells in the second phase of Fuling shale gas field
LI Ya’ nan1,YU Zhanmiao2
1.Drilling Engineering Technology Research Institute,SINOPEC Zhongyuan Petroleum Engineering Ltd.,Puyang457001,Henan,China;
2.No.2Drilling Company,SINOPEC Zhongyuan Petroleum Engineering Ltd.,Puyang457001,He’nan,China
Phase 2 site of Jiaoshiba shale gas project in Fuling is geographically located at the margin of oil reservoir with high stratigraphic dip and multiple faults.The reservoirs are buried deeply,so the vertical hole section shall be long.Therefore,inclination prevention is vital.To enhance recovery factor and decrease drilling cost,the phase 2 engineering is still developed in the mode of well factory.There are more wells in one pad and wellhead distance is shorter in phase 2 than in phase 1,so it is in urgent need to guarantee collision avoidance and obstacle bypass of horizontal wells.The seventh horizontal well (i.e.,Well Jiaoye 81-1HF) on the Jiaoye 81 pad was taken as an example to investigate the collision avoidance which is the construction focus and difficulty in phase 2.The on-site considerations of horizontal well anti-collision were prepared.Well profile of Well Jiaoye 81-1HF was optimally designed based on the historical data of well group on the same pad.The key well locations and hole sections of collision avoidance were determined by simulating the anti-collision data of neighboring wells.Anti-collision technology program and directional construction measure were formulated.Bit and BHA were optimized.And thus,collision between one well and its neighboring well was avoided and the operation risk was reduced.It is indicated that collision avoidance and obstacle bypass are realized successfully at 7 horizontal wells on the same pad and their hole trajectories are smooth with accurate targeting.It provides the foundation for casing job and cementing.And it can be used as the reference for the collision avoidance and obstacle bypass of cluster horizontal wells in the second phase of Fuling shale gas project.
shale gas; factory-like drilling; horizontal well; collision avoidance and obstacle bypass; trajectory control; Fuling
李亞南,于占淼.涪陵頁(yè)巖氣田二期水平井鉆井防碰繞障技術(shù)[J].石油鉆采工藝,2017,39(3):303-306.
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1000–7393(2017 )03–0303–04DOI:10.13639/j.odpt.2017.03.009
: LI Ya’ nan,YU Zhanmiao.Collision avoidance and obstacle bypass technology for horizontal wells in the second phase of Fuling shale gas field[J].Oil Drilling & Production Technology,2017,39(3): 303-306.
李亞南(1987-),2010年畢業(yè)于東北石油大學(xué)石油工程專業(yè),現(xiàn)主要從事定向井及鉆井工藝研究。通訊地址:(457001)河南省濮陽(yáng)市華龍區(qū)中原東路鉆井工程技術(shù)研究院。 E-mail:liyanan19870506@163.com