海上热采井防污染工艺管柱及配套工具

针对海上热采井采用“注、采两趟管柱”导致压井液污染地层的问题，研制了海上热采防污染工艺管柱及配套工具。该工艺管柱主要由热采防污染封隔器、热采防污染井下开关和热采插管密封器组成。热采防污染封隔器坐封、悬挂在井内后， 即可通过热采插管的上提、下放，控制井下开关的开启或关闭，从而有效封隔油层和上部空间的通道，避免压井液进入地层。通过配套工具的地面实验、模拟井实验和高温实验，表明该工具坐封、坐卡、丢手动作灵活无卡阻，密封锚定可靠，满足高温、中温、常温多轮次交替变化下的承高压性能，井下开关开启、关闭动作灵活，能够满足海上热采井多轮次注气和采油需要。

Research on contamination-proof technique strings and supporting tools for offshore thermal recovery wells

In view of stratum contamination by kill fluid which is caused by both injection strings and production strings in offshore thermal recovery wells, the contamination-proof technique strings and supporting tools for offshore thermal recovery wells have been developed. The technique strings is mainly composed of contamination-proof packer for thermal recovery, contamination-proof down-hole switch and intubation sealer for thermal recovery. When the contamination-proof packer is set and suspended in the well, it can open or close the down-hole switch by lifting or lowering the thermal recovery intubation, hence effectively sealing the passageway between the oil reservoir and upper space and avoiding kill fluid from entering the stratum. Ground test, simulation well test and high temperature test have shown that this tool is flexible in setting, getting locked and releasing without jamming and the seal anchoring is reliable. It can withstand high pressure under multi-cycle alternative changes among high, medium and normal temperatures. The down-hole switch can open and close flexibly, and can meet the requirement of multi-cycle gas injection and oil recovery for offshore thermal recovery wells.