油井水泥石脆性降低的途径及其作用机理  

Reduction in friability of well cement stone and its function mechanism

作　　者：华苏东[1] 姚晓[1] 

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210009

出　　处：《中国石油大学学报（自然科学版）》2007年第1期108-113,共6页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家高新技术'863'计划项目(2003AA327120);南京工业大学博士创新基金资助项目(BSCX200503)

摘　　要：针对国内油田薄油层井、小间隙井和侧钻井固井后射孔及后续增产措施造成的水泥环脆裂（即二次窜流）问题，为了降低水泥石的脆性，正确评价不同材料对水泥石韧性或弹性的影响，对掺有胶乳、橡胶粉和PVA纤维水泥石的抗折强度、抗压强度、抗冲击功和弹性模量等力学性能进行了研究，并对3种材料的作用机理进行了剖析。研究结果表明，与净浆水泥石相比，掺有胶乳和橡胶粉水泥石的弹性模量分别降低了69％-76％和49％-60％，掺有PVA纤维水泥石的抗冲击功和抗折强度分别提高了9％-89％和16％-37％。胶乳、橡胶粉与水泥水化产物的有效铰接和桥联作用显著提高了水泥石的弹性，PVA纤维的有效阻裂作用显著提高了水泥石的韧性。Aiming to the problem of the brittle fracture of cement sheath caused by perforation and other production enhancing measures after well cementing of thin oil reservoir wells, latex, robber powders and PVA fibers were studied to reduce cement stone friability and distinguish the toughness and elasticity of cement stone accurately. The mechanical properties of well cement stone mixed latex, robber powders and PVA fibers were measured, and the function mechanism of above mentioned materials was analyzed. The results show that compared with net cement stone, the elastic modules of well cement stone with latex and rubber powders are decreased by 69% - 76% and 49%- 60% respectively. The flexural strength, the impact work of cement stone with PVA fibers are increased by 9% - 89% and 16% - 37% respectively. Articulation and bridging of latex and rubber powders can improve the elasticity of well cement stone remarkably. Crack resistance behavior of PVA fibers can improve the toughness of cement stone markedly.

关 键 词：固井 水泥环 油井水泥 韧性 胶乳 纤维 橡胶粉 弹性模量 

分 类 号：TE256.6[石油与天然气工程—油气井工程]