Comparative Analysis of a Jack-up Drilling Unit with Different Leg Systems

The jack-up unit is one of the best drilling platforms in offshore oil fields with water depth shallower than 150 meters.As the most pivotal component of the jack-up unit,the leg system can directly affect the global performance of a jack-up unit.Investigation shows that there are three kinds of leg structure forms in the world now:the reverse K,X,and mixing types.In order to clarify the advantage and defects of each one,as well as their effect on the global performance of the jack-up unit,this paper commenced to study performance targets ofa deepwater jack-up unit with different leg systems(X type,reverse K type,and mixing type).In this paper a typical leg scantling dimension and identical external loads were selected,detailed finite element snalysis(FEA)models were built to simulate the jack-up unit's structural behavior,and the multi-point constraint(MPC)element together with the spring element was used to deal with the boundary condition.Finally,the above problems were solved by comparative analysis of their main performance targets(including ultimate static strength,dynamic response,and weight).

Applying the vantage PDMS to jack-up drilling ships

The plant design management system （PDMS） is an integrated application which includes a database and is useful when designing complex 3-D industrial projects. It could be used to simplify the most difficult part of a subsea oil extraction project-detailed pipeline design. It could also be used to integrate the design of equipment, structures, HVAC, E-ways as well as the detailed designs of other specialists. This article mainly examines the applicability of the Vantage PDMS database to pipeline projects involving jack-up drilling ships. It discusses the catalogue （CATA） of the pipeline, the spec-world （SPWL） of the pipeline, the bolt tables （BLTA） and so on. This article explains the main methods for CATA construction as well as problem in the process of construction. In this article, the authors point out matters needing attention when using the Vantage PDMS database in the design process and discuss partial solutions to these questions.

Study on the evaluation index system and evaluation method for self-elevating drilling unit design

In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis （GRA）, in which the analytic hierarchy process （AHP） was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms.

Mathematically modeling the main dimensions of self-elevating drilling units

The present status of self-elevating drilling units was analysed. Based on statistics of the main dimensions of self-elevating drilling units, a mathematical model was established using stepwise return procedures and a back-propagation neural network. mathematical model is applicable and reliable. The of the main dimensions of self-elevating drilling Analysis of examples of calculations showed that the model is useful for mastering the essential variations units and can be used for technical and economic analysis as well as in conceptual designs of drilling units.

The motion performance and mooring system of deepwater semi-submersible drilling unit

This paper analyzes the motion performance and mooring system of deepwater semi-submersible drilling unit in the district of the South China Sea using the MOSES procedure system. After the 3-D panel model of the unit was built, the 3-D diffraction-radiation theory was used to obtain the hydrodynamic loads on the wet surfaces and the response amplitude operators （RAO） of the unit. According to the environmental data, the short-term motion response to motion performance of the unit is predicted by the spectral method. Then a time-domain calculation was done to analyze the motion of the unit with its mooring system. The research results can be a reference for the model test of unit.

Optimization of drilling and blasting operations in an open pit mine——the SOMAIR experience

Drilling and blasting play vital roles in opencast mining. These operations not only affect the cost of production directly but as well and significantly, the overall operational costs. This research was carried out to find a possible way of optimizing the drilling and blasting operations in an open pit mine of Somair (Société des Mines de l’Air), in the Niger Republic. In order to optimize the drilling operation, the time taken by two drilling machines to accomplish the same task was analyzed statistically. The result indicates that the Down the Hole Hammer Drilling Rig (DMNo406) is more efficient than the Drill Master (DM405). The relative unit consumption of two explosives (Explus and Nitram 9), when used under the same operating conditions, were also considered and the results indicate Explus to be more economical per unit consumption with a range of 0.15 g/t–0.183 g/t, when compared with Nitram 9 with a unit consumption range of 0.19 g/t-0.24 g/t in the study area.

Discussion on Key Points of Wind Load of Jack-up Unit

The anti-overturning ability and structure safety of jack-up unit in in-place condition are often affected by environment loads, especially wind load. According to the MODU rule, the projected area method is used for calculating the wind load. However, the calculated results are conservative and not good for structure optimization design. In this paper, a 400 ft jack-up is studied as an example. Based on the wind tunnel test and numerical simulation method, some key points of wind load calculation, such as shielding effect, lift effect and shape coefficient of component, are discussed. The study shows that the points mentioned above, which are ignored in the MODU rule calculation, result in the conservative result.

Repacking practice for G-3 engineering driller power unit with drive shaft of dual channel reverse circulation

In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.

Study on the Design Method of the Jack-up＇s X-Type Cantilever Allowable Load Nephogram

The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical reference which can evaluate the jack-up's drilling ability, design the cantilever structure and instruct a jack-up manager to make the operations safe. The intent of this paper is to explore the interrelationships between the cantilever position, drilling floor and the loads including wind force, the stand set-back weight etc., through analyzing the structure and load characteristics of the x-type cantilever and the simplified mechanics model with the restriction of the maximum moment capacity of the cantilever single side beam. Referring to several typical position designs load values, the cantilever allowable load nephogram is obtained by using the suitable interpolation method. The paper gives a method for cantilever allowable load design, which is proved reliable and effective by the calculation example.

基于门控循环单元网络的钻井井漏智能监测方法

井漏是钻井过程中常见的钻井风险,若对该风险发现、处理不及时,极易导致井塌事故,轻则延长施工周期,重则危害现场人员人身安全。为了提高油气井钻井过程中井漏风险识别的准确性,降低风险识别对人为经验的依赖,结合钻井参数的非线性以及长时依赖特征,提出了一种基于门控循环单元(Gated Recurrent Unit,GRU)网络的井漏风险智能识别方法。该模型以池体积、出口流量和立管压力作为监测参数构建GRU网络,能够提取监测参数的时间序列特征,以实现对井漏风险的准确识别。利用现场实测钻井数据对模型进行了实验测试,结果表明,该方法对井漏风险的识别准确率达到了90.1%,优于长短期记忆网络的识别结果。

基于惯性测量单元的旋挖钻机钻具姿态测量方法

为实时获取钻孔过程中钻具的姿态信息,提高机手掌握成孔垂直度,设计了一种基于惯性测量单元的钻具姿态测量方法。该方法采用三轴加速度计、磁力计和陀螺仪构成惯性测量单元,建立基于四元数的姿态测量非线性模型,并采用基于四元数的扩展卡尔曼滤波算法,有效降低振动等干扰信号的影响,提高钻具姿态解算的准确性。实验结果表明,该方法能够有效避免振动对动态测量的干扰,实现旋挖钻机姿态的准确测量,为旋挖钻机施工提供实时、准确的姿态监测手段,为桩基施工质量提供重要保障。

Reliability Research on Fatigue Life of Spots of Semi-submerged Drilling Unit

Based on the calculated results of the simplified model of deep-water semi-submerged drilling unit,the model of deep-water semi-submerged drilling unit is built by reasonably simplifying.The large vertical cylinder(MacCamy-Fuchs)formula is modified according to this model,then the modified formula is utilized to obtain the wave load spectrum which acts on the columns of the semi-submerged drilling unit.By using ANSYS software,a spectrum analysis process is established to calculate the stochastic response spectrum of the model that is subjected to the wave load spectrum which has been calculated.Then the power spectral density of stochastic response of the key nodes can be obtained.Based on the Miner model and the first excursion failure criterion,the fatigue life reliability of the key nodes is calculated.

移动式钻井平台零排放技术浅析

近年来,随着全民环保意识不断增强,政府相继出台了系列环保法规,加强对污染物的排放控制。根据渤海地区生态红线保护要求,以实现移动式钻井平台作业过程零污染为目标,定量分析了海洋钻探开发过程中固体污染物、生活污水、工业污水等排放量,优化钻井平台原液舱功能分布,校核了钻井平台结构强度与稳性,实现海洋钻探过程中的污染物零排放技术方案。相关技术成果已成功应用于多个钻井平台,可推广至同类大型海洋作业装备。

钻井液冷却装置技术发展现状及展望

随着国内油气钻井向着万米深井开发,钻井过程中井底温度越来越高,因此需要对钻井液降温冷却以保护井下工具仪器。而国内钻井液冷却装置普遍存在设备超大、超高以及设备冷却降温幅度不大的现状。本文从介绍国外钻井液冷却装置技术现状出发,阐述了国外钻井液冷却装置技术现状;同时结合国内钻井工况,重点分析了国内自然冷却、开式冷却、闭式冷却和强制冷却4种钻井液冷却装置的工作原理、优缺点和适应范围。结合国内钻井技术发展现状,为保障冷却装置降温效果,结合道路运输和环保要求,分析了冷却装置降温机理研究、工程适应性、应用局限性和装置可靠性等关键技术难题,提出了冷却装置技术研发思路,为开发研制适应性强、可靠性高和冷却效果显著的装置提供参考。

手术室个性化护理干预在毛囊单位钻取术联合富血小板血浆治疗雄激素性脱发手术中的应用

目的探讨手术室个性化护理干预在毛囊单位钻取术联合富血小板血浆在雄激素性脱发手术患者中的应用效果。方法将2022年1月至2023年12月在福建省立医院收治的64名行毛囊单位钻取术联合富血小板血浆手术治疗的患者按护理方式不同进行分组,对照组予以手术室常规护理,观察组予以手术室个性化护理干预,并对两组护理前后心理状态、疼痛程度、护理满意度予以对比。结果护理后,观察组患者焦虑评分(41.03±1.53)分、抑郁评分(44.56±3.14)分,小于对照组(P<0.05);观察组术后当天疼痛评分(2.00±1.05)分小于对照组(P<0.05);观察组护理满意度为(93.76%)显著高于对照组的(65.63%),(P<0.05)。结论手术室个性化护理干预可有效缓解毛囊单位钻取术联合富血小板血浆治疗AGA手术患者不良情绪,减少疼痛感,提高护理满意度。

膨胀夹头式自动进给钻应用技术分析

随着航空装备的快速发展,传统手工制孔方式已经不能满足现代化飞机装配制孔需求,根据飞机装配典型应用工况,在保证孔径、锪窝精度前提下,先进高效的半自动制孔技术成为急需突破的关键技术。本文从自动进给钻的实际应用出发,研究了最新膨胀夹头式自动进给钻配套刀具、进给量与转速和叠层厚度等因素对制孔精度的影响,为膨胀夹头式自动进给钻在航空装配制孔的推广应用提供一定参考。

钻爆法隧道上台阶爆破炮孔装药量精细计算方法

目前隧道钻爆法施工技术日趋成熟,但炮孔装药量的精细计算仍缺乏可靠的经验或理论公式。基于利文斯顿爆破漏斗理论,考虑隧道上台阶爆破方案设计中的炮孔孔距、排距和倾角等因素,提出了倾斜与垂直炮孔负担爆破岩石体积的计算方法。考虑岩石坚固性系数、爆生临空面方向等因素的影响,建立了炸药单耗优化计算方法。最后,基于炮孔装药量经验体积计算公式,提出了隧道上台阶爆破炮孔装药量精细计算的方法。依托临沂至滕州高速公路寨山隧道开挖试验段,验证了炮孔装药量计算方法的可靠性,研究成果对指导隧道精细爆破具有重要意义。

老龄海洋钻井平台综合评估和转型方向

为有效应对能源结构由油气向新能源加速调整引起的老龄海洋钻井平台需加速转型的情况,开展老龄海洋钻井平台评估和转型研究,以优化相关企业的装备结构,有序推进老龄装备的转型。从老龄海洋钻井平台的现状、评估依据、评估模型、评价指标及其权重的设定、转型梯队和触发条件等方面进行全面论述,提出针对老龄海洋钻井平台的综合评估方法和转型方向,为企业相关管理决策的制定提供参考。

自升式钻井平台码头耐久试验

采用有限元分析和钻头喷嘴当量直径计算方法合理设计、选用试验工装,采用试验水箱在码头进行耐久试验,并优化试验流程。经实际项目检测,试验工装选取经济、合理,试验流程简单、高效,能保证平台各类试验的连贯性,避免反复拖航插拔桩,从而缩短平台的调试周期,节省试验费用,降低平台试验风险。研究成果可供同类项目中类似试验的开展参考。

不同水文地质单元水害预防及治理研究

大社矿在巷道掘进过程中严格执行超前钻探和超前物探工作,虽然能有效预防水害事故,但存在工程量大、费用高、施工工期长等问题,影响矿井正常衔接。针对这一情况,本文以《煤矿防治水细则》中要求的“一矿一策、一面一策”为基础,根据大社矿矿井未来生产规划及不同水文地质单元的特性,分区制定水害治理措施,保证矿井安全生产的同时,节约生产成本,确保矿井正常生产衔接。