熱采井溫度對套管性能的影響及預(yù)應(yīng)力值計算方法

Effect by Thermal Well Temperature on Casing Properties and Calculation Method for Pretension

摘要: 熱采井套管柱受力較普通井套管柱更為復(fù)雜,通過對現(xiàn)有部分資料的調(diào)研和分析,介紹了熱采井溫度對套管性能參數(shù)的影響規(guī)律,建立了套管屈服強(qiáng)度、彈性模量、線膨脹系數(shù)隨溫度變化的回歸模型。同時,針對近年來現(xiàn)場套管設(shè)計中出現(xiàn)的幾個問題進(jìn)行了探討,指出在進(jìn)行熱采井套管柱設(shè)計時應(yīng)注意的問題?？紤]到溫度對套管性能參數(shù)的影響,舉例計算了熱采井套管所需要的預(yù)應(yīng)力值,供套管柱設(shè)計人員參考。

Abstract: The stress condition of the thermal well casing string is more complicated than that of ordinary well casing string.Based on analysis of relevant information available, rule of the effect by thermal well temperature on the casing property values is discussed.A regression model is established for the empirical correlations of casing yield-strength, Young's modulus, and linear expansion coefficient vs temperature.Furthermore, several problems encountered with during field designing of thermal well casing string in the recent years are discussed, and certain key issues are emphasized for the said design.Take into account the effect of temperature on casing property values, examples of calculation of the pretension for the thermal well casing are made, providing valuable information to casing string designers.