固井施工中套管柱居中的优化设计

OPTIMUM DESIGN OF CASING CENTRALIZING IN CEMENTING

李晓江

Li Xiaojiang

大庆石油学院秦皇岛分院

目前在固井施工中,对于套管柱居中的设计主要是设计扶正器的位置与间距。现有的设计方法一般均作两种简化处理:一是从整个套管柱中截取一段来独立考虑,对各段间的相关性忽略过多;二是对井眼位置的空间变化作了许多假定。在这两种简化处理后,所得出的结论只能比较粗略地反映套管的居中程度,各个扶正器的位置与间距不是最优的,更难以了解套管在井中任意一个截面上的偏心情况。为此,本文在更严格的力学模型基础上提出了一套优化设计方法。对井眼的实际位置不作任何简化,并对整个套管柱的变形进行整体分析,可精确求出套管在井眼中的空间偏移位置和扶正率。

The desisn of casing strings centralizing is to determine position and pace of casing centralizers in cementing. Precious design considered one section of casing strings only without considering interaction of adjacent sections and made so many assumptions on geometric configuration of borehole that degree of centralization of casing string was described inaccurately. As a result, it is impossible to optimize the locations and pace of casing and to get knowledge of eccentric condition of casing strings in borehole. This paper presents a mechanic model for optimum designing without any assumptions of borehole,so that the eccentric condition and centralizing rate of casing can be gotten accurately by analyzing the deformations of casing strings integrally.

10.3969/j.issn.1000-7393.1995.03.001