套管柱拉力—扭矩模型及在定向井中的应用

Tension-torque model for casing strings and its application to directional wells cementing

李国庆 夏柏如 姜文勇 李子丰

LI Guoqing XIA Bairu JIANG Wenyong LI Zifeng

中国地质大学，北京　100083 大庆油田有限责任公司井下作业分公司，黑龙江大庆　163453 燕山大学,河北秦皇岛066004

China University of Geosciences, Beijing 100083, China Downhole Service Sub-Company of Daqing Oilfield Company Limited，Daqing 163453, China Yanshan University，Qinhuangdao 066004, China

在固井作业中，不仅要将套管下入到设计深度，还要在注水泥浆结束后，上提、下放和旋转套管以提高固井质量；在某些特殊情况下，还有可能将套管起出。在固井施工之前，应该对套管柱进行拉力和扭矩分析，以确认套管强度和地面设备是否满足要求。文中在考虑钻柱刚度的基础上建立了定向井套管柱拉力扭矩模型，提出了套管柱强度校核方法。对大庆油田的一口定向井的套管柱进行了拉力、扭矩和强度分析。结果表明，该井套管具有足够的强度，可以实施上提、下放和旋转套管作业。

In cementing operation, it is not only needed to trip in casing to the designed depth, but also needed to trip in, trip out and rotate the casing to improve the cementing quality after cement injection. In some special cases, casing may be tripped out from the well. Casing string tension-torque analysis should be made to determine whether the strength of casing and the surface equipments meet the requirements. In this paper, the tension-torque model for casing in directional wells is introduced, and the strength verification method is developed. The casing string used in a directional well in Daqing Oilfield is analyzed. The result shows that the casing of the well has strength is high satisfactory strength. The operation of tripping in, tripping out and rotating casing strings can be implemented.