THE CALCULATING RESEARCH OF THE INFLUENCE TO CASING PIPE,CEMENT SHEATH AND FORMATION BY VIBRATED WATER INJECTION
振动注水对套管、水泥环及地层影响的计算研究

In order to evaluate the influence of vibrated water injection to casing pipe, cement sheath and formation, the research was conducted. Based on the simplified mechanics model of casing pipe and cement sheath in layer and mechanics of elasticity, this paper provided the axi-symmetrical stress formula of casing pipe, cement sheath and layer. According to the stress relation of casing pipe inner wall, between casing pipe and cement sheath, cement sheath and stratum in flat, the mathematic model on stress and the solution was deduced, when the elastomers are contacted. On the basis of mechanics of materials and the simplified curve of water injection pressure while vibrated injection, selecting the proper parameters, this paper analyzed the working condition and calculated the maximum stresses in casing pipe, cement sheath and formation rock while alternating internal pressure and deduced the related curves between maximum stresses and alternating water injection pressure. Finally, the conclusion is that the pulse pressure caused by vibrated water injection can not damage to casing pipe, cement sheath and formation.