Abstract: A number of horizontal wells are completed with screen liners in China. Annular space exists between the screen liner and well wall, leading to well damage once water invades into the wellbore. It is a world-class bottleneck to control water cut and increase oil production. Use of chemicals for isolation of the annular in the later period and directional treatment of water producing spots become an important technological research direction. However, the “gravity collapse” effect makes conventional materials unable to fill the horizontal annular. The two-step crosslinking isolation chemicals are difficult to be controlled on the site. Based on magnetic materials, a type of fluid was developed with high thixotropic and solidification capacity, namely annular chemical packer colloids for horizontal well. The structure can be rapidly restored within 10 to 15 seconds after thinned by shearing. It can completely fill the horizontal annular. Under the effect of temperature, the solidification system based on multi-function group will transition to a high-strength solid annular chemical packer (ACP) from the thixotropic fluid. Under the temperature of 45 to 130°C, the solidification time can be controlled within three to 12 hours, the pressure bearing capacity exceeds 20MPa and the ACP loading error is ±5 meters. The process is safe and reliable and able to meet the demand for later-period treatment of horizontal wells for different types of oil reservoirs. The pilot test in conducted for the first time in China. Currently, it has been used in more than 10 domestic oil and gas fields, becoming an effective technological measure to control water cut and increase oil production from horizontal wells completed with screen liners.

Key words: horizontal well, screen liner completion, annual chemical packer, annular isolation, thixotropic property, directional treatment, control water cut and increase oil production

摘要： 我国水平井有相当一部分为筛管完井,筛管与井壁间存在管外环空,见水后危害极大,控水增油成为公认的世界级难题。后期管外化学分段,实现出水部位定向治理成为重要的技术方向。但“重力坍落”效应导致常规材料无法填充水平环空,二次交联分段材料现场工艺控制困难。以磁性材料为基础发明高触变可固化流体,即水平井环空化学封隔器预聚体,剪切变稀后结构恢复迅速（10~15s）,可完全立体充填水平环空,并在温度作用下基于多功能团固化体系由触变流体形成为高强固体环空化学封隔器。45~130℃条件下,固化时间3.0~12h可控,承压能力大于20MPa,定位放置偏差±5m,工艺安全可靠,满足不同类型油藏水平井后期治理需要。国内首次开展了矿场先导试验,目前已应用于国内10多个油气田,成为筛管完井水平井控水增产有效技术途径之一。

关键词: 水平井, 筛管完井, 环空化学封隔器, 管外分段, 触变, 定向治理, 控水增油