提高地层承压能力技术

A Study on the Enhancement of Formation Bearing Resistance.

地层承压能力的影响因素主要有地层岩性、地层裂缝发育程度、温差、黏土矿物水化和钻井液漏失量、钻井液侵入时间、堵漏材料的类型和粒度组成、钻井和堵漏工艺水平。用改进的DL型堵漏实验仪对一系列浓度的刚性封堵剂、核桃壳以及它们复配的堵漏浆封堵模拟裂缝后的承压能力进行了评价,得出了刚性封堵剂由于强度高、不易被压碎、不水化,在裂缝中能架桥、填充、堵死裂缝,提高裂缝填塞层的承压能力。在DN2-4井和莫深1井上的现场实验也证实了,复配使用刚性封堵剂与核桃壳的堵漏浆能很好地封堵裂缝,提高封堵层的承压能力,且封堵层不容易再次发生漏失,可增加一次成功提高地层承压能力的几率。

Formation bearing resistance is generally affected by those factors such as the formation rocks, fracture, temperature, clay hydration, volume of mud loss, time for the drilling fluid to invade into the formation, lost circulation materials, as well as drilling and dental work techniques. The bearing resistance of an artificial core with fractures was tested on a modified DL LCM tester with drilling fluids containing different concentrations of rigid plugging agent and nut shell. It was concluded that the use of rigid plugging agent improved the bearing resistance of formations because of its high strengths and resistance to hydration, as well as its ability to bridging, packing and sealing. By using the rigid plugging agent and nut shell in well DN2-4 and Moshen-1, it was shown that the compound LCMs can improve the bearing resistance of the formation to which mud loss occurred. Mud loss was completely stopped after the dental work using the compound LCM mud.