高能气体压裂对套管井壁的破坏

Damage to the Wall of Cased Hole by High Energy Gas Fracturing

本文对受高压作用的套管井壁进行了弹塑性分析和计算。计算结果表明,除了射孔附近外,套管不会发生大程度破坏。由于高压作用,高能气体压裂除了会产生主裂缝之外,在井筒附近会产生大量主体为径向的小裂纹,这对增强压裂效果有利。而且这些裂纹不会沿井筒轴向长距离扩展而使油层与其它不希望连通的层段贯通。

This paper makes an elastic and plastic analysis and calculation of the wall of a cased hole under high pressure. The calculated results indicate that the casing will not be damaged severely except near the perforated holes. Besides the principal fractures, the high energy gas fracturing will produce many tiny fractures mainly in rdial direction in the vicinity of the wellbore because of the high pressure, which is favourable to enhancing the effect of fracturing. Furthermore, these tiny fractures will not propagate to a long distance in the direction of weUbore axis, and hence not communicate the producing interval with other adjacent ones.