钻遇大段盐膏层的定向井钻井工艺及现场试验

发布时间：2018-05-16 15:58

本文选题：盐膏层 + 定向井设计　；参考：《东北石油大学》2015年硕士论文

【摘要】：盐膏层由于存在蠕变现象,在钻井施工过程中容易造成井壁失稳,从而引发缩径卡钻、坍塌卡钻、粘附卡钻和井漏复杂情况与事故,施工作业风险极大。本文通过对乌兹别克KC区块盐膏层地层、岩性特征等进行综合分析,以KC-100bis为例,从钻井液性能、井身结构设计、钻具组合、轨迹控制优化设计及工程措施等方面,进行详细分析,研究设计出适合该区块的厚盐层定向钻井技术方案。主要体现在以下5方面:(1)在钻井液性能方面,钻井液密度不仅要抑制盐膏层的蠕变,又要保持井壁稳定。利用欠饱和盐水钻井液钻进盐膏层,使盐岩在欠饱和盐水钻井液中适当溶解,可以达到扩大井眼的目的。(2)在定向井设计方面,本文充分考虑了盐膏层蠕变引起的套损问题,同时考虑了盐膏层蠕变对下套管和固井作业的影响,为了给盐膏层固井赢得时间,降低固井的成本与风险,保证下套管顺利和盐膏层段的固井质量,提出了相应的套管程序设计方案。(3)在井眼轨迹控制优化方面,考虑到石膏层井段不能进行定向作业的特点,需要在进入盐膏层之前实现稳斜钻进的井身结构设计。(4)在钻具组合方面,考虑到采用“满眼”钻进,容易发生井下事故,因此需要选择合适的工具和合理的钻具组合,钻进中使用了双扶正器钻具组合,避免了下钻遇阻而被迫长井段划眼,又起到稳定井斜的作用。(5)工程措施方面,针对盐膏层的特点,提出了一系列合理的工程措施,减少了井下复杂情况的发生,缩短了钻井周期。通过对该油田区块的整体钻井优化设计研究及现场应用,得到了适合于该区块厚盐层的定向钻井技术方案,结果表明,使用该套工艺,井下复杂情况大幅度降低,钻井周期大幅度缩短,经济效益较很好。
[Abstract]:Due to the existence of creep phenomenon in salt paste layer, it is easy to cause shaft wall instability during drilling and construction, which can lead to shrinkage drill, collapse drill, sticking hole and leakage complex situation and accident, so the risk of construction operation is great. In this paper, through the comprehensive analysis of salt gypsum formation and lithologic characteristics in Uzbek KC block, taking KC-100bis as an example, from the aspects of drilling fluid performance, well structure design, drilling tool combination, trajectory control optimization design and engineering measures, etc. Through detailed analysis, the directional drilling technology scheme of thick salt formation suitable for this block is studied and designed. In the aspects of drilling fluid performance, the density of drilling fluid should not only restrain the creep of salt paste, but also keep the wellbore stable. In the design of directional wells, the use of undersaturated salt water drilling fluid to drill salt layers and the proper dissolution of salt rock in undersaturated salt water drilling fluids can achieve the purpose of expanding boreholes. In the design of directional wells, the problem of casing damage caused by creep of salt gypsum layers is fully considered in this paper. At the same time, the influence of salt layer creep on casing and cementing operation is considered. In order to win time for salt paste formation cementing, reduce the cost and risk of cementing, and ensure the smooth casing down and cementing quality of salt gypsum interval. This paper puts forward the corresponding casing program design scheme. (3) considering the characteristics of gypsum formation section which can not be directional operation in the aspect of hole trajectory control optimization, The design of wellbore structure which needs to realize stable drilling before entering salt paste. 4) in the aspect of drilling tool combination, considering the "full hole" drilling, which is prone to downhole accidents, it is necessary to select the appropriate tool and reasonable drilling tool combination, The double centralizer drilling tool combination is used in drilling, which avoids drilling difficulties and is forced to draw holes in long section, and plays a role of stabilizing well deviation. In respect of engineering measures, a series of reasonable engineering measures are put forward in view of the characteristics of salt paste layer. It reduces the occurrence of downhole complex situation and shortens the drilling cycle. Through the optimization design and field application of the whole drilling in this oilfield block, the directional drilling technology scheme suitable for the thick salt layer in the block is obtained. The results show that the downhole complexity is greatly reduced by using this set of technology. The drilling period is shortened by a large margin, and the economic benefit is very good.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE243

【相似文献】