摘要:钻井取心的目的是提供地下原始资料，同时也是获取地层中的岩性和地下含油储量的情况等资料的最直接有效的手段。石油勘探、开发过程都离不开岩心的提取这一步。在开发之前必须要取得完整的第一性资料，只有通过对大量对岩心的分析与研究才能为石油或是天然气的开采制定合理的开发方案。在本次设计中的保压密闭取心技术是在保持地层压力的一种尖端取心技术，它采用了保压取心工具和封闭的液体，通过在井底高压的钻井液驱动下实现内外筒的差动运动来实现关闭内筒的球阀，这样就可以将岩心密封在内筒中,保证取心过程中岩心中油气水不流失，保持地层流体和岩心样本的完整性。当岩心从井底被取出地面后进行冷冻和保存在干冰中。在冻结的情况下，然后可以拆卸内筒并把岩心切成几个小段带到实验室去分析实验。不论在什么时候保压岩心必须在干冰中保持冷冻，这样才会取得具有原始地层压力的岩心，对取全取准地层资料具有重要意义。因此，不断的完善改进保压密闭取心工具显得十分重要。

关键词：保压  密封 取心工具 岩心

ABSTRACT:Drilling core purpose is to provide the raw data of the underground, and the formation lithology and underground water reserves in case data such as the most direct and effective means. The extraction of oil exploration and development is inseparable from the core. Must want to get a complete primary data before development, only through the analysis and study of a lot of core ability for the extraction of oil or gas reasonable development scheme. In the design of the holding pressure coring technology is a cutting-edge in keeping formation pressure coring technique, it adopts the pressure maintaining coring tools and closed liquid, through the high pressure of drilling fluid on bottom of inside and outside the cylinder driven by differential movement to realize the closed inner barrel ball valve, so that it can be the core tube, seal, ensure coring in cores in the process of oil and gas is not lost water, keep the formation fluid and the integrity of the core sample. When the core from the bottom hole is removed after the ground were frozen and stored in dry ice. In freezing conditions, then you can remove the tube and the rock eager into several small pieces to the lab analysis experiment. No matter at what time the holding must remain frozen in ice cores, such ability can obtain core with the original formation pressure, to take all take accurate stratigraphic information is of great significance. Therefore, the improvement of the constantly improve the holding pressure coring tool is very important.

Key words:pressure maintaining ;hermetic sealing ;coring tool ;core;