套管抗挤毁强度主要影响因素试验研究

对17根Ф177.80mm套管进行几何尺寸测量、材料性能及外压挤毁试验,研究了几何尺寸、屈服强度及残余应力对套管抗挤毁强度的影响。结果表明:各因素综合影响套管的抗挤毁强度;椭圆度变化>0.5%、壁厚不均匀度>10%或其不同截面间变化>5%均将明显降低套管的抗挤毁强度;椭圆度及其不同截面间变化<0.2%,将明显提高套管的抗挤毁强度。在屈服强度达到钢级要求的同时,控制好套管的几何尺寸精度并降低残余应力,可以生产出具有较高抗挤毁强度的套管。

Experimental Study on Influence Factors of Casing Collapse Resistance Strength

Study each factor influence for casing collapse resistance strength based on full scale col- lapse test results of seventeen Ф177.80 mm casings and there geometry and material properties test results. The results show that casing collapse resistance strength was influenced by geometry accuracy, yield strength and residual stress together. Ovality variation more than 0.5 %, eccentrici- ty more than 10 %, or eccentricity variation more than 5 %, casing collapse resistance strength will be reduced obviously. Ovality and there variation less than 0.2%, casing collapse resistance strength will be increased obviously. Casing with excellent collapse resistance strength will be produced through making yield strength in appropriate level, controlling the geometry accuracy and reducing residual stress.