Well Blowout: Well Control Equipment Fails Accidentally

Well Blowout: Well Control Equipment Fails Accidentally?

井喷：井控装备意外失防？

口本刊记者/王云建  Reporter/ Wang Yunjian

中国船级社/段明星 李朋亮 陈瑞峰 万波China Classification Society/Duan Mingxing Li Pengliang Chen Ruifeng Wan Bo

As of the publication of this issue, more than 100 days have passed since the U.S.-Mexico oil spill. The incident is still under investigation, and no matter what the final official explanation is, it is certain that this disaster was a rather serious "blowout" accident in the history of human offshore oil and gas development.

截至本刊发稿前，美国墨西哥漏油事件已经历时百余日。事件尚在调查之中，不管最终的官方解释是什么，可以肯定的是，这起灾难是人类海洋油气开发史上一次相当严重的“井喷”事故。

Who opened the blowout "magic bottle"?

是谁开启了井喷“魔瓶"？

What is a "blowout"? In the process of drilling and workover, when the liquid column pressure in the well is lower than the formation pressure, the formation fluid will enter the wellbore and flow to the wellhead. If there is natural gas in the formation fluid, the natural gas will slip under pressure and rise rapidly, and the volume will expand rapidly. If no effective measures are taken to control it, the formation fluid will flush out of the wellhead and cause a blowout. When there is an ignition source near the wellhead, it is very likely that a fire will cause a tragedy, destroying the oil reservoir, wasting resources and polluting the environment. Around 22:00 on April 20. This is what happened on the Gulf of Mexico platform.

何为“井喷”？ 在钻井、修井过程中，当井内的液柱压力小于地层压力时，地层流体就会进入井筒向井口流动，如果地层流体中存在天然气，天然气就会带压滑脱快速上升，体积迅速膨胀。如果不采取有效措施进行控制，地层流体就会冲出井口造成井喷。在井口附近存在引火源的清况下，极有可能失火酿成惨剧，破坏油藏、浪费资源和污染环境。4月20日22:00左右．墨西哥湾平台就上演了此情此景。

In the story of "One Thousand and One Nights", the fisherman accidentally caught a magic bottle and accidentally released the devil. For oilfield operators, a "blowout" is like opening a "magic bottle" unintentionally. Although the probability is small, once opened, the consequences are serious. However, how was the "magic bottle" of the oil well in the Gulf of Mexico opened?

在《一千零一夜》的故事中，渔夫偶然捞到了一只魔瓶，不小心放出了魔鬼。对于油田作业者来说，“井喷”就好比是无意打开了“魔瓶”。尽管概率很小，但一旦打开，后果很严重。然而，墨西哥湾出事油井这一“魔瓶”是如何被打开的呢？

Since the explosion of the platform in the Gulf of Mexico, the incident has attracted great attention from relevant units in China, including oil companies, oilfield technology service companies, universities and scientific research institutes. Some technical experts, scholars and technicians have collected a large amount of foreign information, conducted many technical discussions, and have been paying attention to the latest progress of the event. At present, the accident analysis mainly focuses on the process operation on the day of the blowout. According to the normal operation process, cement plugging is a process in the well abandonment operation. But before, the pressure dropped after the seawater replaced the mud, and a terrible disaster occurred in this link.

墨西哥湾平台爆炸以来，该事件引起国内，包括石油公司、油田技术服务公司、高校及科研院所在内相关单位的高度关注。一些技术专家、学者及技术人员搜集了大量国外信息，进行了多次技术研讨，一直关注着事件的最新进展。目前事故分析主要集中在井喷当天的工艺操作上。按照正常的作业流程，打水泥塞是弃井作业中的一道工序。但此前，海水替换泥浆后压力下降，就在这个环节发生了可怕的灾难。

"The technology of offshore oil exploitation is complex, and any small mistake may have catastrophic consequences," China National Petroleum Offshore Engineering Company said after analysis. "As long as the drilling rig in the Gulf of Mexico where the explosion occurred, the accident can be completely avoided. , Zhou Shouwei, deputy general manager of China National Offshore Oil Corporation and academician of the Chinese Academy of Engineering, believes that "if the technology and design operations are strictly followed, the probability of such a major accident would have been very small."

“海洋石油开采工艺技术复杂，任何一个小的失误都可能带来灾难性后果，”中国石油海洋工程公司分析后认为，“发生爆炸事故的墨西哥湾钻井平台只要操作得当，事故完全可以避免。此前，中国海洋石油总公司副总经理、中国工程院院士周守为认为，“如果严格遵循技术和设计操作，发生这么大事故的概率原本非常小”。

"The Gulf of Mexico accident was an explosion caused by a well control problem," a technical expert pointed out. In addition to the major suspicion of process operation, as one of the effective measures for 'three-level well control' to prevent oil leakage, the blowout preventer system Well control equipment such as , diverter system is the second important line of defense to prevent blowouts. But in this accident, the blowout preventer failed.

“墨西哥湾事故是井控问题导致的爆炸，“一名技术专家指出，除了工艺流程操作有重大嫌疑之外，作为‘三级井控’、防止漏油的有效措施之一，防喷器系统、分流系统等井控装备是阻止井喷的第二道重要防线。但此次事故中，防喷器却未能凑效。

Based on this, it is speculated that on April 20, the deepwater drilling platform in the Gulf of Mexico lost its defense because of the first two lines of defense, and the "magic bottle" was opened in an instant....

据此推测，4月20日当天，墨西哥湾深水钻井平台因为前两道防线失防，“魔瓶”刹那间被开启……。

The "crime and punishment" of deep water well control equipment?

深水井控设备的“罪与罚”？

After the oil spill, according to foreign media reports, some experts and people raised serious doubts about the defective design of the cement "shell", the use of high-risk casing, the failure of the blowout preventer and the failure of the automatic backup system. On May 11, BP, Transocean Drilling, and Halliburton attended the U.S. Congressional hearing for the first time. When being questioned, BP accused Transocean Drilling of its blowout preventer in court, and the other two companies also pointed the finger at it. Point directly.

漏油事件发生后，根据外媒报道，一些专家、人士对水泥“外壳”设计有缺陷、使用高风险套管、防喷器失灵及自动备用系统失效这三个方面，提出了严重质疑。5月11日，BP公司、越洋钻探公司、哈里伯顿三方首次出席美国国会听证会，在接受质询时，BP公司当庭指责越洋钻探公司的防喷器失效，另外两家公司也矛头直指。

The truth will always come to light. Experts pointed out that deepwater oil and gas development has huge risks and many challenges. Even as a reflection on normal events, the industry should check and self-examine themselves. For the oil equipment manufacturing industry, it should also appreciate the pain of "scraping bones" of others.

真相总会水落石出。专家指出，深水油气开发风险巨大、挑战重重，即使作为正常事件下的反思，业界也应该自查自省，对石油装备制造业来说，更应当体味别人“刮骨”之痛。

As a "safety equipment", the deep water blowout preventer system is the core well control equipment. Its function and reliability are related to the safety of personnel and property in deep water oil drilling, as well as the protection of the marine environment. According to industry insiders, in addition to the blowout preventer system, the deep water well control equipment also includes a diversion system, a well killing/throttling system and a well flow treatment system. As well as high pressure mud systems and cementing systems associated with well control operations. If you operate the raccoon, blowout accidents can be completely prevented and dealt with.

作为“安全设备”，深水防喷器系统是核心的井控装备，其功能和可靠性关系到深水石油钻探中人员和财产的安全，也关系到海洋环境的保护。业内人士介绍，除防喷器系统系统外，深水井控装备还包括分流系统、压井/节流系统和井流处理系统。以及与井控操作相关的高压泥浆系统和固井系统。如果操作合狸，完全可以预防和处理井喷事故。

According to reports, the platform explosion accident occurred before the last cement plug was injected during the well abandonment operation. The deepwater BOP group used at that time had a combination of subsea wellhead devices: wellhead connector + test ram + lower variable diameter ram + upper Variable Diameter Ram BOP + Casing Shear BOP + Shear Shear Ram BOP + Lower Annular BOP + Riser Connector + Upper Annular BOP + Flexible Joint + Riser adapter (Figure 1). The rated pressure of the ram BOP is 103.4.2MPa, the rated pressure of the upper annular BOP is 68.9SMPa, and the rated pressure of the lower annular BOP is 34.47MPa. The BOP control system is produced by CAMERON, except that it has no voice-activated backup system, it has emergency release function, automatic shear function, automatic shutdown function (Dead man System) and remote control vehicle (ROV) operation function (Picture 2).

据介绍，平台爆炸事故发生在弃井作业注最后一个水泥塞之前，当时所用的深水防喷器组其海底井口装置组合为：井口头连接器＋测试闸板＋下可变径闸板＋上可变径闸板防喷器＋套管剪切防喷器＋全封剪切闸板防喷器＋下环形防喷器＋隔水管连接器＋上环形防喷器＋挠性接头＋隔水管适配器（图1）。闸板防喷器的额定压力是103.4.2MPa，上环形防喷器的额定压力是68.9SMPa，下环形防喷器的额定压力是34.47MPa。该防喷器控制系统由CAMERON公司生产，除了没有声控备份系统，它具有应急解脱功能、自动剪切功能、自动关闭功能（Dead man System）和遥控潜水器(ROV)操作功能（图2）。

Technically, this deep water BOP system is powerful. The emergency release system can quickly separate the drilling platform from the wellhead in an emergency. After the automatic shearing system is set to the active state, it can automatically close the wellhead when the lower riser assembly (LMRP) and the blowout preventer group are abnormally disengaged. The automatic shutdown system can automatically start the blowout preventer to close the wellhead when the underwater blowout preventer loses control signal transmission and hydraulic supply. The ROV operating system can operate the BOP through the control panel located on the underwater BOP body.

从技术上来看，该深水防喷器系统功能强大。应急解脱系统可以在紧急情况下实现钻井平台与井口迅速脱离。自动剪切系统设定为启动状态之后，能够在隔水管下部组合（LMRP）与防喷器组非正常解脱的时候自动关闭井口。而自动关闭系统能够在水下防喷器失去控制信号传输和液压供给时，自动启动防喷器关闭井口。ROV操作系统则可以通过位于水下防喷器本体上的控制面板对防喷器进行操作。

But the actual situation is just the opposite. When the blowout occurred, the failed blowout preventer failed to close the wellhead; because the upper and lower parts lost contact, the emergency relief system failed to start; after the platform sank, the ROV operating system also went out of control. In an emergency, a group of 450-ton high-tech blowout preventers were instantly "frozen".

但是实际情况恰恰相反，井喷发生时，失效的防喷器却未能将井口关闭；由于上、下失去联系，应急解脱系统未能启动；在平台沉没后，ROV操作系统也继而失控。紧急情况下，一组450吨重的高科技防喷器瞬间被“冰冻”。

Is it too late to "repair the dead sheep"?

“亡羊补牢”为时不晚？

After the accident, all parties conducted investigation and research on the failure of the blowout preventer, and found that there were many problems with the blowout preventer used in the accident well. For example, in this accident, the emergency release system failed to start, indicating that the control line between the platform and the underwater blowout preventer was damaged, and the operation command could not be transmitted to the actuator. In terms of functional settings, the blowout preventer does not have a voice-activated backup system (using sound wave transmission to control the blowout preventer device), and unlike the regulations in some countries such as Norway, the United States did not mandate this system before the accident.

事故发生后，各方围绕防喷器的失效进行调查研究，发现事故井所用的防喷器存在多个问题。比如，此次事故中，应急解脱系统启动失败，说明平台和水下防喷器之间的控制线路已损坏，操作指令无法传至执行机构。在功能设置方面，该防喷器未设有声控备份系统（用声波传输控制防喷器装置），而与挪威等一些国家的法规不同，事故发生前美国没有强制要求设置这一系统。

In addition, according to the periodic investigation reports of the parties involved in the accident, there are many problems with the blowout preventer itself. First, after the hydraulic system of the blowout preventer is modified, the hydraulic pipeline that should be connected to the variable diameter ram is connected to the test ram. , and the content of this modification is not documented in writing. Second, there were multiple leaks in the hydraulic system of the blowout preventer, and one of the two subsea control boxes lost part of its function. Finally, the rubber parts of the blowout preventer were severely damaged during drilling operations. Large pieces of rubber were found in the mud that returned.

另外，据事故相关方的阶段性调查报告显示，防喷器本身存在许多问题，首先，防喷器液压系统经过改装后，本该与可变径闸板相连的液压管路与测试闸板相连，而此次改装的内容未有书面文档记录。其次，防喷器的液压系统多处出现泄漏，两个水下控制箱中的一个失去了部分功能。最后，防喷器的橡胶部件在钻井施工的过程中被严重损坏。在返上的泥浆中发现大块的橡胶碎片。

In response to the failure of the blowout preventer exposed by the accident, the U.S. Department of the Interior Mineral Management has made a number of strict regulations on the deep water blowout preventer. The main contents include: requiring operators engaged in offshore drilling to review past operations to ensure that their well control equipment complies with federal regulations; The function conforms to the original design; an independent third party is required to prove that the BOP system is compatible with other equipment on the platform and compatible with the construction well; the deep water BOP is required to be equipped with ROV operating system, automatic shearing system, and automatic shutdown system and voice-activated backup system, and test the ROV operating system; and require an independent third party to prove that the fully enclosed shear ram can cut all sizes of pipe strings in the wellbore.

针对事故暴露出来的防喷器失效问题，美国内政部矿产管理对深水防喷器做出了多项严格规定。主要内容包括：要求从事海上钻探的作业者对以往的作业进行回顾，保证其井控设备符合联邦政府法规的规定；要求在开始钻新井和恢复钻井时，有独立第三方证明防喷器组的功能符合最初的设计；要求有独立第三方证明防喷器系统与平台上的其他设备要兼容和与施工井相适应；要求深水防喷器设有ROV操作系统、自动剪切系统、自动停机系统和声控备份系统，并对ROV操作系统进行试验；并且要求有独立第三方证明全封剪切闸板能够剪断井眼内所有尺寸的管柱。

The main suppliers of underwater blowout preventers are Cameron, Hydril and Shaffer. At present, the new generation of deep water blowout preventers has made new breakthroughs in the pressure compensation of underwater accumulators, the enhancement of ram closing force and the monitoring of control circuit faults. The accident will be able to re-examine the reliability of the relevant performance, and will provide an important reference for future technological development.

水下防喷器的主要供应商有Cameron 、 Hydril和Shaffer。目前新一代的深水防喷器产品，在水下蓄能器压力补偿、闸板闭合力增强和控制线路故障监控等方面又有新的突破。此次事故将得以从新审视相关性能的可靠性，对今后技术发展将提供重要借鉴。

Deep water oil drilling in my country is in its infancy, and domestic research on deep water BOPs has just been carried out. This accident has important implications for the use and research of deep water BOPs in my country: in the functional design and selection of BOP systems, The requirements of the deep water marine environment for well control operations should be fully considered, an emergency control system that meets construction safety requirements should be set up, and the reliability of the BOP system should be enhanced; BOP test technology; learn from the experience and lessons of this accident, and improve the regulations, technical specifications and supervision mechanisms related to deep water well control.

我国深水石油钻探处于起步阶段，国内对深水防喷器的研究也刚刚开展，此次事故对我国深水防喷器的使用和研究具有重要的启示：在防喷器系统的功能设计和选用方面，应全面考虑深水海洋环境对井控操作的要求，设置满足施工安全要求的应急控制系统，增强防喷器系统的可靠性；更加重视深水防喷器系统的试验和维护保养工作，研究更加优化合理的防喷器试验技术；汲取此次事故经验和教训，完善深水井控相关的法规、技术规范和监管机制。

The lessons from the oil spill in the Gulf of Mexico may rewrite and improve the market access standards for well control equipment. "It's not too late to make amends." For manufacturing companies, it may usher in the next development opportunity.

墨西哥湾漏油事件的教训，或将改写和提高井控装备的市场准入标讹。“亡羊补牢，为时不晚。”对制造企业来说，或许会迎来下一个发展机遇。

Link------

链接------

Gulf of Mexico Incident Platform and Well Archives

墨西哥湾出事平台及油井档案

["Deep water Horizon"]

[“深水地平线”]

Deep water Horizon is a fifth-generation semi-submersible drilling platform designed by R&B Falcon with a working water depth of 2,438 meters and a drilling depth of 9,144 meters. The daily rent is $533,000. On September 2, 2009, the world's deepest oil well was drilled at 10,683 meters.

Deep water Horizon号为第五代半潜式钻井平台，由R&B Falcon设计，工作水深2438米，钻探深度9144米。日租金53.3万美元。2009年9月2日，钻探了当时世界上最深的油井10683米。

The platform started construction in December 1998 and was delivered by South Korea's Hyundai Heavy Industries in February 2001. The cost is 3.65 US dollars, and the current market price is about 560 million US dollars. It has a displacement of 52,587 tons, a length of 121 meters, a width of 78 meters, a height of 97.4 meters, a draft of 23 meters, a total installed power of 42 megawatts, and a capacity of 130 people. The outer diameter of the riser is 21 inches, the platform weight is 32,588 tons, and the displacement is 52,587 tons. It is dynamic positioning for the DP-3.

该平台于1998年12月动工，200.1年2月由韩国现代重工交付，造价3.65忆美元，目前市场价格约为5.6亿美元。排水量52587吨，长121米，宽78米，高97.4米，吃水23米，总装机功率42兆瓦，定员130人。隔水管外径为21英寸，平台重量32588吨，排水量52587吨，为DP-3动力定位。

[Accident oil well]

[出事油井]

Well 252#-01 in the Mississippi Canyon block is located in the Maconda exploration area in the Louisiana state of the United States. The Macondo structure is an exploration vertical well; the drilling depth is 5596 meters, and the urban water depth of the operation area is 1544 meters. On April 22, 2010, the Deep water Horizon sank 400 meters northeast of the wellhead.

密西西比峡谷区块252#-01井，位于美国路易斯安那州海洋Maconda探区，Macondo构造，属于勘探直井；钻探深度5596米，作业区城水深1544米。2010年4月22日，Deep water Horizon号沉没于井口东北方400米。

[Operators and Contractors]

[作业者与承包商]

BP has a 65% interest, the US Anadarko Petroleum Company and Japan's Mitsui & Co. have 25% and 10% respectively. Operating water depth: 1524 meters; Offshore distance: 77 kilometers; Oil company: BP; Drilling contractor: Transocean; Cementing service company: Hardan Bojie; Subsea BOP supplier: Cameron company.

BP拥有65%的权益，美国Anadarko石油公司和日本三井物产公司分别拥有25%和10%的权益。作业水深：1524米；离岸距离：77公里；油公司：BP；钻井承包商：瑞士越洋钻探公司（Transocean）；固井服务公司：哈旦伯颉；水下防喷器供应商：Cameron公司。

At the time of the accident, there were 126 people on the platform, including 79 employees of Transocean Drilling Company, 6 employees of BP and 41 employees of contractors.

事故发生时，平台上共有126人，其中越洋钻探公司的员工79名，BP员工6名和承包商人员41名。

All Rights Reserved, Copyrights@ccscpetro.2022.09   Contact Email :clarkoilgas@qq.com

Keywords关键词：井喷,井控装备,液柱压力,地层流体,水泥塞,石油开采工艺,防喷器系统,深水井控设备,高风险套管,上可变径闸板防喷器,隔水管连接器,隔水管适配器,应急解脱功能,自动剪切功,自动关闭功能,遥控潜水器(ROV)操作功能,水下蓄能器,压力补偿,维护保养,监管机制.

                             blowout, well control equipment, liquid column pressure, formation fluid, cement plug, oil extraction process, blowout preventer system, deep water well control equipment, high risk casing, upper variable diameter ram blowout preventer, riser connector, Riser adapter, emergency release function, automatic shear function, automatic shutdown function, ROV operation function, underwater accumulator, pressure compensation, maintenance, supervision mechanism.

Disclaimer 免责声明:This article is only used for learning and communication, and any  commercial use is prohibited. The copyright belongs to the original author. If it causes trouble to the original author, please contact the publisher to delete it. 本文章仅限于学习交流使用，禁止用于任何商业用途，版权归原作者所有。如给原作者造成困扰，请联系发布人删除。

Poster发布人:  Clark Guo,CCSC Technology,Shanghai,China, 2022.09   Youtube: ClarkOilGas  

                Wechat & WhatsApp:  +86 13764749879         Email:  clarkoilgas@qq.com 

►Youtube: ClarkOilGas