Hydraulic fracturing experiments of highly deviated well with oriented perforation technique
Hydraulic fracturing experiments of highly deviated well with oriented perforation technique
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DOI：
10.12989/gae.2014.6.2.153
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发表时间：
2014-02
影响因子：
3.2
通讯作者：
H. Zhu;J. Deng;S. J. Liu;Min Wen;C. Peng;Ji R. Li;Zijian Chen;Liangqiang Hu;Hai Lin;D. Guang
中科院分区：
文献类型：
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作者：
H. Zhu;J. Deng;S. J. Liu;Min Wen;C. Peng;Ji R. Li;Zijian Chen;Liangqiang Hu;Hai Lin;D. Guang
抽象的。为了研究不同射孔角度（射孔方向与最大水平主应力之间的夹角）对油气饱和地层大斜度井水力压裂裂缝起裂和扩展的影响，采用4 0 0 ^3mm3水泥块，在无量纲相似准则的基础上进行了室内水力压裂实验。当射孔沿最大水平主应力方向布置时，可产生平面裂缝。当射孔角度为45°时，裂缝首先从井身上部射孔开始，然后转向最大水平主应力方向。当井斜角和射孔角度均在45° ~ 90°之间时，裂缝很难从井眼下部射孔段起裂。井方位（井筒轴线与最大水平主应力之间的夹角）对裂缝几何形状影响不大，但主要增加了裂缝的粗糙度、裂缝的连续性和次生裂缝的数量，同时也增加了裂缝的起裂和扩展压力。大斜度井应采用定向射孔技术，以获得单平面裂缝。如果井斜角较小，裂缝可能贯通。
Abstract. In order to investigate the effect of different perforation angles (the angle between the perforation direction and the maximum horizontal principal stress) on the fracture initiation and propagation during hydraulic fracturing of highly deviated well in oil & gas saturated formation, laboratory experiments of the hydraulic fracturing had been carried out on the basis of non-dimensional similar criteria by using 400^3 mm 3 cement cubes. A plane fracture can be produced when the perforations are placed in the direction of the maximum horizontal principal stress. When the perforation angle is 45°, the fractures firstly initiate from the perforations at the upper side of the wellbore, and then turn to the maximum horizontal principal stress direction. When the well deviation angle and perforation angle are both between 45° and 90°, the fractures hardly initiate from the perforations at the lower side of the wellbore. Well azimuth (the angle between the wellbore axis and the maximum horizontal principal stress) has a little influence on the fracture geometries; however it mainly increases the fracture roughness, fracture continuity and the number of secondary fractures, and also increases the fracture initiation and propagation pressure. Oriented perforating technology should be applied in highly deviated well to obtain a single plane fracture. If the well deviation angle is smaller, the fractures may link up.