摘要
井筒压力波动是钻井过程中不可避免的潜在安全隐患。特别是固井环节,在薄弱地层,套管下放速度过快,很容易压漏地层,因此薄弱地层固井环节套管下放速度的控制显得尤为重要。文中以赫-巴流变模型为基础,计算井筒激动压力,在薄弱层段,以钻井时最大循环压耗与静液柱压力之和来代替下套管时有效液柱压力最大值,建立了新的套管安全下放速度计算模型。实例验证,误差为8.6%,表明该模型在薄弱地层具有较高的计算精度,可以为现场薄弱层段下放套管提供一定的参考。
Pressure fluctuation in the wellhole is an inevitable potential security risks during drilling. Especially during well cementation in the weak formations,it is easy to cause formation breakdown when casing running velocity is too fast,so it's important to control casing running velocity during cementing process. In this paper,the wellbore fluctuation pressure was calculated using Hershel-Buckley rheological model. The sum of the maximum circulation pressure loss and hydrostatic pressure during drilling was taken as the maximum effective hydrostatic pressure during casing running and a new model for calculating casing running velocity in the weak layers was set up. The model was verified by the practice,the error was 8. 6%,which showed that the model produced high calculation accuracy,providing reference for casing running in weak layers.
出处
《钻采工艺》
CAS
北大核心
2017年第2期17-19,共3页
Drilling & Production Technology
基金
国家自然基金项目“深水钻井隔水管-导(套)管力学特性研究与水下井口稳定性分析”(编号:51574261)
关键词
套管
薄弱地层
赫巴流体
激动压力
最大安全下放速度
casing
weak formation
Hershel-Buckley fluid
fluctuation pressure
maximum velocity of safe casing running
