提高水泥胶结强度的套管黏砂技术研究　　

Study on adhering sand on casing to improve cementing strength

郝明 艾池 高长龙 刘小娟 李晗

HAO Ming AI Chi GAO Changlong LIU Xiaojuan LI Han

东北石油大学提高油气采收率教育部重点实验室，黑龙江大庆　163318 大庆油田有限责任公司第八采油厂，黑龙江大庆　163514 辽河油田特种油开发公司，辽宁盘锦　124010

Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education in China, Northeast Petroleum University, Daqing 163318, China No.8 Production Plant, Daqing Oilfield Co., LTD., Daqing 163514, China Special Oil Development Company of Liaohe Oilfield, Panjin 124010? China

为提高固井水泥胶结强度，对黏砂套管—水泥环间各界面进行强度校核，建立黏砂套管水泥胶结强度计算模型，分析胶结剂厚度与砂粒半径的比值、黏砂密度、胶结剂抗剪切强度及水泥环抗压强度等因素对水泥胶结强度的影响。研究结果表明：当胶结剂厚度和砂粒半径的比值为1时，黏砂套管水泥胶结强度最大，且在其他条件不变时，胶结剂厚度和砂粒半径的比值相同，对应的黏砂套管水泥胶结强度也相同；在临界黏砂密度内，黏砂套管水泥胶结强度与黏砂密度和胶结剂抗剪切强度呈线性增长关系；当水泥环抗压强度小于胶结剂抗拉强度时，黏砂套管水泥胶结强度为与胶结剂抗拉强度相关的定值，当水泥抗压强度介于胶结剂抗拉强度和1.5倍胶结剂抗剪切强度之间时，黏砂套管水泥胶结强度随水泥环抗压强度增大而增大，当水泥抗压强度大于1.5倍胶结剂抗剪切强度时，黏砂套管水泥胶结强度为与胶结剂抗剪切强度相关的定值。因此，当胶结剂厚度和砂粒半径的比值为1、黏砂密度为80%、胶结剂中添加质量分数为13%的四乙烯五胺固化剂及水泥环抗压强度大于1.5倍胶结剂抗剪切强度时，黏砂套管水泥胶结强度可达最大值。

To improve cementing strength, the interface strength between sand adhering casing and cement sheath was tested, and a calculating model of sand adhering casing cement strength was established. It also analyzed the influence on the cementing strength by the ratio of joint compound thickness to sand particle radius, sand adhering density, jointing compound shear strength and cement sheath compressive strength. The study results showed that when the ratio of jointing compound thickness and sand particle radius is 1, the cementing strength is maximum, and the cementing strength varied with the ratio of jointing compound thickness and sand particle radius. Within the critical sand adhering density, the cementing strength increase linearly with the increase of sand adhering density and jointing compound shear strength. When the ratio of jointing compound thickness and sand particle radius is 1, the sand adhering density is 80 percent, the amount of additive tetraethylenepentamine in jointing compound is 13 percent and the cement compressive strength is greater than 1.5 times of jointing compound shear strength, the maximal cementing strength of sand adhering casing can be achieved.