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11.
针对煤矿井下钻场人员需求大、安全隐患多、一人操作难以同时控制钻机动作并从全局视角知悉钻机运行状态等问题,引入了数字孪生技术,设计开发了钻机远程服务平台。该平台系统以ZDY25000LDK钻机为载体,融合了钻机远程控制系统、数字孪生模型和参数监测系统3方面技术,通过检测与执行层、数据传输层和远程集控层实现钻机远程控制、钻机运行全生命周期映射与参数监测。钻机远程控制系统实现了实时远距离控制钻机,数字孪生模型能够映射钻机各运动部件的运动状态,并能通过仿真实验为钻探施工提供先验参考,参数监测系统实现了对钻机状态参数和钻进参数的实时监测。基于该钻机远程服务平台,进行了平台的功能性和实时性验证。试验结果表明:钻机远程服务平台能够实现钻机远程控制,并从全局视角上映射和监测钻机运行状态和参数,通过数字孪生体仿真,得出钻机上扣过程中动力头回转速度和给进速度的最优比值为4.28,与实际上扣情况相符。平台操作方便、实时性高、可靠性好、人机交互友好,为煤矿井下钻探工作的减人增效和智能化升级提供了解决方案。
相似文献12.
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Occurrence and exploration of gas hydrate in the marginal seas and continental margin of the Asia and Oceania region 总被引:5,自引:0,他引:5
Ryo Matsumoto Byong-Jae Ryu Sung-Rock Lee Saulwood Lin Shiguo Wu Kalachand Sain Ingo Pecher Michael Riedel 《Marine and Petroleum Geology》2011,28(10):1751-1767
Supplies of conventional natural gas and oil are declining fast worldwide, and therefore new, unconventional forms of energy resources are needed to meet the ever-increasing demand. Amongst the many different unconventional natural resources are gas hydrates, a solid, ice-like crystalline compound of methane and water formed under specific low temperature and high pressure conditions. Gas hydrates are believed to exist in large quantities worldwide in oceanic regions of continental margins, as well as associated with permafrost regions in the Arctic. Some studies to estimate the global abundance of gas hydrate suggest that the total volume of natural gas locked up in form of gas hydrates may exceed all known conventional natural gas reserves, although large uncertainties exist in these assessments. Gas hydrates have been intensively studied in the last two decades also due to connections between climate forcing (natural and/or anthropogenic) and the potential large volumes of methane trapped in gas hydrate accumulations. The presence of gas hydrate within unconsolidated sediments of the upper few hundred meters below seafloor may also pose a geo-hazard to conventional oil and gas production. Additionally, climate variability and associated changes in pressure-temperature regimes and thus shifts in the gas hydrate stability zone may cause the occurrence of submarine slope failures.Several large-scale national gas hydrate programs exist especially in countries such as Japan, Korea, Taiwan, China, India, and New Zealand, where large demands of energy cannot be met by domestic supplies from natural resources. The past five years have seen several dedicated deep drilling expeditions and other scientific studies conducted throughout Asia and Oceania to understand gas hydrates off India, China, and Korea. This thematic set of publications is dedicated to summarize the most recent findings and results of geo-scientific studies of gas hydrates in the marginal seas and continental margin of the Asia, and Oceania region. 相似文献
14.
随着PDC钻头的广泛使用,因PDC钻头选型与钻遇地层的不匹配,或PDC钻头本身质量问题,也遇到一些井下复杂情况。此文介绍NP6-1井在311.2mm井段使用PDC钻头钻至井深2878.76m时,PDC钻头从公扣根部折断留在井底,加工公锥和采取适当措施成功地打捞出落鱼,避免侧钻,挽回了经济损失。该井成功打捞出PDC钻头,为同类型的井下落鱼或小落鱼提供参考与借鉴。 相似文献
15.
Sven Petersen Peter M. Herzig Thomas Kuhn Leander Franz Mark D. Hannington Thomas Monecke 《Marine Georesources & Geotechnology》2013,31(3):175-193
ABSTRACT From September to October 2002, shallow drilling, using the submersible (5 m) Rockdrill of the British Geological Survey and the German R/V Sonne revealed critical information on the subsurface nature of two distinct hydrothermal systems in the New Ireland fore-arc and the Manus Basin of Papua New Guinea. Drilling at Conical Seamount significantly extends the known surface extent of the previously discovered vein-style gold mineralization (up to 230 g/t Au) at this site. Drilling the conventional PACMANUS volcanic-hosted massive sulfide deposit recovered complexly textured massive sulfide with spectacular concentrations of gold in several core sections including 0.5 m @ 28 g/t Au, 0.35 m @ 30 g/t Au, and 0.20 m @ 57 g/t Au. Shallow drilling is a fast and cost efficient method that bridges the gap between surface sampling and deep (ODP) drilling and will become a standard practice in the future study of seafloor hydrothermal systems and massive sulfide deposits. 相似文献
16.
深水钻井隔水管紧急脱离后的反冲响应 总被引:1,自引:0,他引:1
深水钻井中,在恶劣海况或浮式平台定位失效等情况下,需紧急断开隔水管与水下防喷器的连接。隔水管突然脱离后会加速向上反冲,如果反冲作用控制不当,可能威胁钻井平台、隔水管体和水下井口的安全。介绍了国外隔水管紧急脱离与反冲响应的研究情况,分析了隔水管紧急脱离的原因与程序、脱离后的反冲过程、反冲控制方式和成功脱离标准、反冲响应的分析方法。建议:由于南海深水海况复杂,作业者需制定紧急脱离的预案和作业规程,并进行紧急脱离操作培训;由于隔水管紧急脱离后的反冲响应涉及多个非线性瞬态过程,研究者应该开展隔水管紧急脱离测试和反冲响应模拟计算,开发隔水管反冲响应分析软件。 相似文献
17.
Becasuse of the deep water depth and long riser of deepwater drilling, the stability of subsea wellhead is threatened. Meanwhile, the setting depth of conductor directly affects the mechanical stability of subsea wellhead. Through analyzing the impact of different factors on the setting depth of conductor, we found that the bearing capacity growth factor of subsea soil has a great influence on the setting depth of conductor. However, the coefficient is a regional and empirical constant, which seriously affects the accuracy and reliability of the results. In this paper, probability statistics and geostatistics methods are employed to count the bearing capacity growth factor of target point's adjacent wells, as well as transplant and predict the target point through differential arithmetic, which can obtain the predictive value of target point's coefficient containing probability information. Finally, we can obtain the setting depth range with credibility of conductor. This is conducive to designers to calculate the setting depth of conductor with other uncertain factors taken into account, and reasonably control the potential risks. 相似文献
18.
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自升式钻井船桩靴的插拔过程将会对临近井口平台的桩靴基础产生不利影响。开展了室内模型试验研究,将试验结果与理论分析结果相结合,得到了桩靴插拔的影响范围及影响范围内土体强度的变化规律,并推导了桩靴插拔影响区内临近桩靴承载力的计算方法,与模型试验结果进行了对比验证。研究表明,桩靴插拔后砂土相对密实度降低,其降低程度随距桩靴距离的增加而逐渐减小,影响范围约为1倍桩靴直径。受桩靴插拔影响,临近桩靴的承载力下降,降低比例随两桩靴相对间距的增大而减小,随桩靴相对插深的增加而增加。当两桩靴相对间距大于2倍插拔桩靴直径时,可认为桩靴插拔对临近桩靴基础承载力无影响。 相似文献
20.