Φ114.3 mm×8.56 mm 140V套管抗外挤能力研究

Study on External Collapse-resistance of Φ114.3 mm×8.56 mm 140V Oil Casing

针对石油套管抗外挤能力计算这一热点问题,选取10支Φ114.3 mm×8.56 mm 140V套管进行几何尺寸和机械性能检测,并通过挤毁试验得到其抗挤强度;在考虑几何缺陷和实际力学性能的情况下,建立计算套管抗挤强度的有限元模型,对比模拟结果、理论计算结果及试验结果表明:模拟结果与试验结果相近,偏差-0.77%~+7.0%,而理论计算结果误差较大,偏差23.84%~37.56%。该有限元模型还可用来分析壁厚不均度和椭圆度对该规格套管抗挤强度的影响。

Addressing the hot issue of calculation of the oil casing external collapse-resistance,10 pieces of theΦ114.3 mm×8.56 mm 140V casing are selected and subjected to both geometric dimension measurement and mechanical property tests.And the pipes are also subjected to the collapse test to determine their collapse resistance.Meanwhile based on the consideration of the geometric defects and the actual mechanical properties of the pipes,a FEA model for calculating the collapse strength of the casing is set up.After comparing the results of the simulation,the theoretic calculation and the tests,it is demonstrates that the result of the simulation is close to that of the tests,showing a deviation of-0.77%-+-7.0%,whereas the theoretic calculation result shows an obvious error,i.e.a deviation of 23.84%~37.56%.Thanks to the above mentioned model,the influence by the wall thickness unevenness and the ovality on the collapse re-sistance of the said oil casing is analyzed.