论文部分内容阅读
准确计算油气输送管的实际屈服强度对合理确定输送压力有重要影响。该文分析了4种应力状态下对屈服强度有明显影响的钢管轴向应力,发现管材横向小试样试验时,轴向应力为零,工厂静水压试验时,轴向应力小于零,裸露钢管静水压试验时,轴向应力为环向应力的一半,埋地服役状态时,轴向应力为0.3倍环向应力。并从理论和试验两方面分析了实物钢管屈服强度与管材小试样屈服强度的差别。理论计算表明,4种应力状态下,屈服时von Mises理论计算的钢管环向应力值大于或等于Tresca理论计算值,其中裸露钢管受内压状态下,von Mises理论计算的管道屈服环向应力为1.15倍管材屈服强度,Tresca理论计算值为1.0倍,6根钢管爆破试验及小试样拉伸试验表明,该值为1.18倍。von Mises理论比Tresca理论更适合油气输送管的屈服计算。
Accurately calculating the actual yield strength of oil and gas pipe has a significant impact on the reasonable determination of conveying pressure. In this paper, the axial stress of steel pipe with obvious influence on yield strength under four kinds of stress conditions is analyzed. It is found that the axial stress is zero when small pipe transverse test is carried out and the axial stress is less than zero when exposed to hydrostatic test. Hydrostatic test of steel pipe, the axial stress of half the hoop stress, buried in service state, the axial stress of 0.3 times the hoop stress. The difference between the yield strength of the real steel tube and the yield strength of the small tube specimen is analyzed from both theoretical and experimental aspects. The theoretical calculation shows that the hoop stress calculated by von Mises theory is greater than or equal to the calculated value of Tresca under four kinds of stress conditions. The hoop stress of the pipe calculated by von Mises theory is 1.15 times the yield strength of pipe, Tresca theoretical calculated value of 1.0 times, six steel pipe burst test and small sample tensile test showed that the value of 1.18 times. von Mises theory is more suitable than Tresca theory for yield calculation of oil and gas pipelines.