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井下套管损坏机理及围压分析-英文翻译

套管钻井和阶段性工具的结合：一种独特的

缓和井底条件的方法

Combination of Drilling With Casing and Stage Tool Cementing:

A Unique Approach to Mitigating Downhole Conditions

作者：R. Robinson, SandRidge Ener gy, and S. Rosenber g, SPE, B. Lirette, SPE, and A.C. Odell, SPE, Weatherfor d Intl. Ltd.

起止页码：1-12 出版日期（期刊号）：2007年2月20日

出版单位：SPE/IADC Drilling Conference

摘要

目前科罗拉多州重大挑战是在派深斯盆地西北部的天然气田钻井和套管方案的设计。这一地区地质情况较为复杂，其与浸渍形成岩床，导致“克鲁克德钻洞“的

产生。因此造成的问题，包括钻井时失去流通，并未能使水泥下到水泥工作台的9

5/8 寸套管，可能造成套管达不到总钻探的深度。

通过对问题的勘察，管理人员在该地区得出结论认为，一种不同的方法得到授权是和选定的套管钻井（DWC作为以前勘察的替代。钻井与套管，加上固井的表面外壳，预计将产生显著有效的表面和套管钻孔作业，从而减少了非生产性时间

（NPT和相关的成本。

本文回顾了在派深斯盆地中遇到的问题即传统的表面钻井和套管作业。同时也审查了钻井监督关于套管和钻井的实施方案。

背景

自2003 年以来投资方已在派深斯盆地开采天然气。图1显示普通区域的地图。在遇到比较困难的钻井和套管表面制造空穴，钻井监督人员有丰富的经验来判断以

及解除困难。这通常是针对约3100 英尺的钻采深度。钻井所造成的问题浸渍形成

岩床，失去了循环间隔，而且岩石的强度不够。常规钻井泥浆马达使用的做法和低

重位（钻压）钻探了十二寸又四分之一深。表面空穴因为高钻压与常规钻井测试结果往往有严重的增加倾向，有时超过7。。表l 列出了一个典型的常规钻具组合，

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在这一领域以前用于钻表面孔。表2显示了钻孔所采用的常规钻具组合以及钻井套管在地表井得到的最大的孔倾斜测量值。

表面地质孔主要包括砂岩，粉砂岩和灰岩与互特约页岩。图 2 显示了一个典型不同成分的分布形成的表面间隔图。自然的断裂往往导致失去循环问题的产生。如果长期没有足够量的钻井液在循环其结果就导致了塌页岩。

经过钻探，钻孔必须要有9 5/8 寸才能和相应的套管配合。这样的话表层套管的计划尺寸显然是有问题的，甚至在套管被冲洗的时候也是如此。许多时候，我们

看到的常规钻孔，施工者未能做到9 5/8 寸套管的计划尺寸。在两个常规钻井下，套管是在300英尺和427英尺之间而且是小于总深度的（TD）. 非作业性时间甚至会达到15 天。

无计划的钻洞往往导致非生产性时间的增加，而且在最坏的情况下，联接作业已被要求，因为开放孔的暴露时间的增加将导致管柱被卡住。还有在最坏的情况下，钻孔的这种情况也往往导致低质量水泥的工作而且必须满足当地的土地管理局（ BLM）的环

保要求。未能分发的水泥表面造成的水泥胶结测井来评价水泥工作的完整性，在反过来，往往导致要采取补救固井和有线行动的需要，以达成一项可接受的质量胶结。这个补救工作往往造成3 至4 天非作业性性时间。表3 显示由于钻井问题、套管运行的问题、固井之前的问题和执行期间的钻井套管问题造成的非作业性时间。

钻井与套管的评价随着钻井作业技术的成熟，经营者开始探讨其他的解决方案以满足以下目标：1 确保表面套管可达计划的深度。

2提供一个有效的方法，减轻表面钻孔，流通和孔稳定的损失问题。

3避免最小偏差所造成的洞导致浸床。

4提供一个有效的固井系统，可以使水泥保持在地表，避免了不必要的补救工作，并满足国土管理局规定。

5尽量减少或消除非作业性事件的产生。

彻底审查钻井数据已经开始执行，包括钻井资料，水泥记录，地质和位置的记录，分析了非作业性时间。记载的非作业性时间大约是32天，在12 1/4 寸处进行观察。从表面间隔的五个井在实施前审查同阶段的套管钻井工具固井技术。其中当遇

到钻探和9 5/8 寸的套管时的大部分非作业性时间和孔的稳定性有关系。管理者决定利用套管钻井，加上在现有的固井系统基础上，提供了最好的条件实现这些目标，

以下是对此的评价：

1获取套管的底部。使用套管钻井技术启用套管钻井达到计划的深度（TD ，从而

尽量减少开放孔的曝光时间。

2钻井时关于流体损失最小的问题。套管钻井技术使环型空间几乎全部保持在钻井作业期间，尽量减少有关塌页岩的问题。

3最小井斜。消除泥浆马达低钻压，并取代了泥电机与套管钻井，钻具组合的角

度将尽量减少建设角度的的倾斜。

4提高旧井工作质量。使用多阶段固井工具和套管钻井钻具组合，启用水泥发给

表面，关键是固井必须满足土地管理局的要求。

设备选型

设备的选择对这项工作的成功至关重要。该项目设备选择如下：

（1）套管接头。经营者原先选定95/8寸，36英尺/磅的J-55支撑套管作为表层套管在钻探计划中。他关切的是疲劳电阻的标准，这依据于成千上万的电阻在套管钻井

作业中。此外，因为这个扭矩依赖于它的最终位置，人们知道支持连接的扭矩值不

变。

为了提高他的一致性和抗疲劳能力，应改良支撑设计，与内部扭矩肩上的中心耦合。印第安纳州这方面，针对扭矩的值，提供了一个积极的制止措施和加强扭矩阻力。此外，同样的修改支撑设计提供了三重锥度的耦合，以减少局部径向轴承强调的交配线程要素，从而增强抗疲劳能力。第二个好处改良支撑设计大大减少破坏并增加了它在该领域的抗疲劳能力。

对于套管钻井，操作员和平常的工作人员使用套管来实施。用套管接头积分肩三锥方块。沉重的跨科中心加强了耦合机构，产生了更清晰的环向应力分布，较高的螺纹接口接触压力，并加强泄漏电阻。

（2）钻擦鞋。该DS31被选为切削结构中最适合应用预测DW（信息技术的工具。它基本上拥有五年的PDC钻头刀刃寿命，使它能转换为钻孔钻擦鞋。该DS3拥有16毫米的PDC刀具和硬质合金衡量保护插入。该指数节旨在让回扩孔能力。

该DS知以允许转换为随后钻与常规钻头。在达到TD之前，以DS3乍为PDC钻头，在这时候一个球下降到钻孔，允许下降到球漏斗内的DS3 ，并封锁了钻井喷嘴流动。该套管柱的压力然后上升大约2000psi，以及DS3^I脚剪切，来迫使工具内活塞下降。这项行动取代钢叶片和PDC切削结构纳入套管，裸眼环。与此同时，固井口暴露。流体循环重新确立通过这些固井港口工具的内在套管, 并下降了闭锁装置以进行充分通风。该工具被设计为完全取代整个切割结构纳入环，最终是凝成的地点。该中心是完全暴露在活塞与钻孔常规磨齿和PDC钻头（一种特殊位或轧机运行不要求）之间。图3显示了DS3E在上升时的钻井平台。

2500PSI 。该工具是一个从事高强度套管作业，四分之一右转和减小下降的的能量和四分之一左转。内

部套管驱动在6 5/8英寸。在常用的连接块上，提出钻机的顶端驱动。内部套管驱动有三个功能：1 ）套管电梯，2 ）补充工具，3 ）套管驱动

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■套管悬挂和轮皆用二沁搀沪弊害 mf 护淬戟离皆乞 ------------------- 一

TCDT 重钻机的顶部驱动。9 5/8 换使用内部套管驱动工具英

寸，36磅/英尺的套管北内部

器的工具。在每个套管接头垂直提高一个位置再旋转，用钻机的管装卸臂，内部套管驱动工具从事套管联结，从事套管作业，其余的套管用; 降低它的平台和套管的联乍管钳来完成. （4）双挡板带回压阀的套管接箍。带一个双挡板带回压阀的套管接箍（图（有三个功能：1 ）机械以及控制障

碍 2 ）浮领的第一阶段顶端雨刷插头，和 3 ）设计是

本浮动领是一个传。这浮领中心还设雨刷插件。浮法

“8寸套管上J

TCDT 轮流第一阶段的水泥泥浆。管去掉，让挡板在关闭的位置运行入挡板降落的第一阶段顶端' 在连接底部的引脚联合9 5/8… （五）机械双级固井工具。机械式它设计成一种机械的活动，力加上压阶段性的工具。从三维的角度看，刷插件（4英寸外径），，以及3 7.25英寸阶段工具的机械强度性能先定DW （信息系统是球。这种回压套管接箍也目同的功能中使用的钻柱浮动常规钻井作业）「个单向检查阀，以防止U 型管返上 I 统的自动填入浮法领与 i 立了一个I B

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行。这

一阶段的工具，有90度扇形硬度又名过氧化固化丁腈 0型圈密圭寸，额定-20至275oF 和6 1/8寸。外径固井端口从操作角度来看，工具设计的开启和关闭压力（ 700至 1000 Psi 以开放和“ > 1200 Psi 以关闭）是在机械强度极限为9 5/8寸套管下进行的即36磅/英尺的J-55套管上运行的。

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处理臂能够解除接触。

最好状况是150转/分钟的扭矩容量2.4万英尺/英镑。

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彻底审查钻井设施的运营商和承包商人员设立钻井套管的内部套管驱动再加上最高顶部驱动的总长，只允许与一个40英尺长套管联合。这也时在预装配钻具组合中长度最大的。

钻井和固井

计划程序要求设置14英寸导管大约120英尺的测量深度，然后钻进

12 3/4寸

套管。插入内径大约1500英尺的导管，利用泥浆马达钻具组合。在这一点上，常规钻具组合是需要拆卸的和套管（12 1/4英寸）钻井作业开始。套管的设置和硬质合金分两个阶段进行。

历史上用于这种情况的是联邦 399-1-5油井，在2006年6月开钻。经过14项工作完成。导

8 ）,

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六）钻配备了 250吨的动滑轮和

限度地减

工具

探平台。该钻机选定套管钻井信息计划是一个单打式钻井平台（图 0

管被定在约120英尺深，内径为12 3/4寸。钻1540英尺的孔，传统的方式是采用泥浆马达钻具组

合。插入牙轮位和淡水流体系统使用。据观察1470

英尺并发生3.75。倾斜的钻孔（12 3/4寸）是12 3/4寸而不是传统的12 1/4英寸，被用来最大

限度地减少绊铰孔中的12 1/4寸套管倾斜度，套管钻井钻具组合。

图9 非旋转钻井套管扶正器

9 5/8英寸X 12 1/4英寸DS3线程锁定的第一次联合套管接走使用常规套管边门梯。非旋转式套管钻井扶正器（图9），跨越了两个止动环，被安放在中间的第二级联合套管的双重挡板阀浮动领上。这个扶正器的定位是在DS3钻头以上的86英

尺处。

总共有6 个非旋转式套管扶正器运行。扶正器运行两边有阶段性工具。用钻机的管装卸臂和下12 1/4 寸套管。套管钻井钻具组合的运行是在12 3/4 寸套管。然而在1057英尺深的钻洞套管是洗涤和扩通过间歇紧点上下的工具。定位机械阶段工具是在套管柱定为1404英尺深。套管钻井开始，用9 5/8 英寸套管。套管钻井在2068 英尺深市没有任何事故的。

联系前面的知识，每个关节都很重要，以及前面的两个高粘度得钻井泵。在2068英尺深，总流通丢失。该钻机的水泵安放在套管的环形空间，并且抽取120桶的水用来填补9 5/8 寸X 12 1/4 寸的油套管环形空间。把空气压缩机放在网上，空气泵水约600转/分钟，并获得了回溃。套管钻井业作业继续钻至2473英尺，空气泵几乎完全停止使用。表面观察到了钻压和扭矩达到到8至15千磅和6至10千

英尺/磅，旋转速度为60至80转/分钟.套管钻井如果没有发生任何事故就持续钻进到计划的总深度的3075英尺。

被安放在内部套管驱动工具的中心，和3英寸酚醛转换球（3.45SG）被替代。内部套管驱动工具的中心重新参与到套管和钻井平台，水泵是用来分DS3球座的渠道。

在施加压力至2700PSI后，替换DS叨片。通过叶片位移来观察钻机的立场管压力表的升降情况。内部套管驱动工具中心被显示是下降的，之后筹备固井，安装顶部水泥。

第一阶段的水泥浆包括12.0 （310袋）和“G'级水泥混合，随后进行的尾矿浆由是一类“ &级（190袋）和15.8进行混合。由水泥泥浆流失失去231桶水。分

2.72

I 2. (I

图10钻头3工具转换和连I 多个一级固井技术被证明是以及减少专％已经实现

管钻井阶段使用的工具与技术

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间减少

0.35 天

较优. 这项技术使运营商，

管钻井技术工具纟

、3天，使非作业性时间减少了接步骤

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减少了的进行 %「，在两工作时间。

自面钻洞工作的非作业性井，非作业性时间减少了

套管钻井的流体损失显著小于表面常规钻洞，据记载在失水中的损失节省多万美兀常规钻井有两项工作是套管在300英尺和427英尺的距离以及深度进行的。口井使用套管钻井技术可以使表面套管到达到计划的深度

所有阶段的工作的固井工具的是在套管钻井水泥返回地面后完成的

时

0和

达4.0

每接工具打开锥体手动下降套管。循环水是每分钟循环

5.5桶水利用钻井泵进行分界。

经过4小时的循环，第二阶段是水泥浆料泵。第二阶段的泥浆包括 12.0 （ 215袋）-

和“G'级混合，其次是尾水泥浆由 15.8（ 80袋）和“G'级结合，大约17吨水泥

分发表面。截止插头下降，成功地实现了

6.4桶/分钟。一位土地管理局的代表见

证固井工作，任何补救井都是需要的.图10是一个示意图序列的钻探 DS3钻头替代，以

及双级固井工艺。

!1 叩 Ml Ml Ml

套管钻井技术使平均井斜减少44 %

所有使用DS3钻头PDC刀片的环没有发生任何事故。全部DS3的钻采用常规牙轮钻头。结论

套管钻井使用一级固井确保主要的水泥工作表面。

套管钻井相比以往的常规钻井减少了非作业性时间。

套管钻井可以使所有的套管放入油井预定深度

DS3钻头是一个成熟的套管钻井工具，钻探完成孔科，钻头与常规钻头被置换

成PDC刀具

专业术语

BHA =井底管柱结构

BLM -土地管理局

CBL =水泥胶结测井

DS3 =钻头3

DwC =钻井与套管

ICDT =内部套管驱动工具

MD =测量深度

NPT =非作业性时间

ROP =渗透速度

R R R =转/分钟

SSS =标准立方央尺

TD =总深度

UCS -无侧限抗压强度

WOB =钻头重量

表在地表井段最大化倾斜的数据比较

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b非作业性时间在很大程度上是由于固井管线和固井作业在套管放入井底管柱结构前不能建

立的循环所导致的。

c一级固井工具曾经是作为套管钻井的井底管柱结构的一部分。

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