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1.
在油田开发中,大负荷解卡是修井作业中常见的工序之一。由于受到地面环境、修井设备的限制,解卡作业的成功率一直比较低。为此,我们引进了液压解卡工具,以液体为动力传递介质,推动井下解卡工具工作,实现大负荷解卡的目的,并且通过6口井的现场实施取得了较好的效果。  相似文献   
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Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control. Similarity measures were obtained through analyzing the certainty and uncertainty of fuzzy membership functions, which were designed based on well-known Hamming distance. It was applied to the fault detection of primary control surface stuck of uninhabited aerial vehicle (UAV). At post-failure control surface, if the UAV is controllable and trimmable using other control surfaces, the UAV is able to fly or return to the safety region through reconfiguration of flight control system. To detect the fault, similarity measure computations were carried out. This result could be applicable with the real-time parameter estimation method. By monitoring the value of coefficients due to the control surface deviation, it becomes aware that the control surface fault occurs or not. The control surface stuck position and value were separated by comparing the trim value with the reference value. This is the advantage of increasing in reliability without adding sensors or with additional low cost.  相似文献   
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介绍了江苏天生港发电有限公司8、9号135MW机组射水抽气器工作特点,分析了其工作时发生的喷嘴堵塞、喷嘴磨损及逆止阀卡涩时的现象,提出了具有针对性的预防措施,从而保证射水抽气器安全运行。  相似文献   
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A stuck drill string results in a major non-productive cost in extended reach drilling engineering.The first step is to determine the depth at which the sticking has occurred.Methods of measurement have been proved useful for determining the stuck points,but these operations take considerable time.As a result of the limitation with the current operational practices,calculation methods are still preferred to estimate the stuck point depth.Current analytical methods do not consider friction and are only valid for vertical rather than extended reach wells.The numerical method is established to take full account of down hole friction,tool joint,upset end of drill pipe,combination drill strings and tubular materials so that it is valid to determine the stuck point in extended reach wells.The pull test,torsion test and combined test of rotation and pulling can be used to determine the stuck point.The results show that down hole friction,tool joint,upset end of drill pipe,tubular sizes and materials have significant effects on the pull length and/or the twist angle of the stuck drill string.  相似文献   
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为解决稠油井开采中井筒出砂严重、管柱容易遇卡和修井机提升力不足的问题,研制出作业井口增力装置。该装置主体由内管、外管、活塞管、端盖、承压环、吊耳、液路元件和密封元件等组成。现场应用表明,作业井口增力装置与修井机配套使用,可使大部分遇卡稠油井得以解卡,同时证明该装置设计合理,操作简单,解卡时几乎没有安全风险。  相似文献   
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磨溪气田水平井射孔枪卡钻解卡工艺技术   总被引:2,自引:0,他引:2  
磨005-H10井和磨017-H3井为磨溪气田雷一^1气藏和嘉陵江气藏的两口水平井,均采用127mm尾管射孔完成,油管传输射孔后即发生卡钻。由于射孔枪与套管间隙小,打捞工具选择困难,再加上水平井的特殊性,解卡工艺难度大,工程风险大。该两口井采用震击器震击解卡工艺和倒扣解卡工艺处理卡钻事故,获得成功,对水平井井下作业和水平井修井具有一定指导意义。  相似文献   
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Glucose and fructose fermentations by industrial yeasts strains are strongly affected by both the structural complexity of the nitrogen source and the availability of oxygen. In this study two Saccharomyces cerevisiae industrial wine strains were grown, under shaken and static conditions, in a media containing either a) 20% (w/v) glucose, or b) 10% (w/v) fructose and 10% (w/v) glucose or c) 20% (w/v) fructose, all supplemented with nitrogen sources varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids) and peptides (peptone). Data suggest that a complex structured nitrogen source is not submitted to the same control mechanisms as those involved in the utilization of simpler structured nitrogen sources, and mutual interaction between carbon and nitrogen sources, including the mechanisms involved in the regulation of aerobic/anaerobic metabolism, may play an important role in defining yeast fermentation performance and the differing response to the structural complexity of the nitrogen source, with a strong impact on fermentation performance.  相似文献   
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People can time travel cognitively because they can remember events having occurred at particular times in the past (episodic memory) and because they can anticipate new events occurring at particular times in the future. The ability to assign points in time to events arises from human development of a sense of time and its accompanying time-keeping technology. The hypothesis is advanced that animals are cognitively stuck in time; that is, they have no sense of time and thus have no episodic memory or ability to anticipate long-range future events. Research on animals' abilities to detect time of day, track short time intervals, remember the order of a sequence of events, and anticipate future events is considered, and it is concluded that the stuck-in-time hypothesis is largely supported by the current evidence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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以某航空器滑油供油系统中的液压滑阀为研究对象,研究摩擦力与液动力对滑阀卡滞的影响。建立阀芯运动的数学模型,包括液压径向力模型、液动力模型和阀芯触壁摩擦力模型。基于AMESim构建滑阀系统模型并进行卡滞现象复现仿真分析,其滑阀受加速度影响,弹簧使阀芯触壁产生的摩擦力过大时导致滑阀卡滞。提出一种滑阀可靠性分析流程,考虑弹簧结构尺寸参数的随机性,采用Monte-Carlo法计算滑阀的可靠性,并对参数进行优化。研究结果表明:弹簧的极限偏差值e1、e2是影响可靠性的主要因素,其中弹簧极限偏差值e2灵敏度更高,通过参数优化获得滑阀无卡滞下的参数适用范围,其分析流程为滑阀中的弹簧选型提供了参考。  相似文献   
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