化工装置中温度计套管频率限制的研究及计算

Study and Calculation of Frequency Limit for Thermo-well

工程应用离不开温度测量,而温度计套管会因流体对套管的作用力过大而导致损坏甚至断裂,进而造成插在套管内的检测元件损坏而影响测量,并产生泄漏及引发事故。分析了温度计套管共振产生的原因以及在共振情况下的动态应力瞬间放大情况。然后,根据ASME PTC 19.3 TW—2010标准分析了温度计套管振动与自然频率f_n^c和漩涡脱离频率f_S之间的关系,以及其他的一些限制条件。最后,通过对温度计套管静态应力和动态应力的分析,以及公式计算,提出了更为全面的温度计套管应力分析和断裂评估方法,使温度计套管避免损坏及断裂。

Temperature measurement is necessary in most of engineering processes. Thermo-wells may be damaged due to excessive force activated by fluids, which will result in the damage of the measuring elements in the thermo-wells so as to cause leakages and accidents. In this article, the cause of producing resonance in thermo-wells and the situation of amplifying dynamic force transiently were analyzed. Then based on ASME PTC19.3 TW-2010, the relation between natural frequency of thermo-wells and the frequency of vortex shedding as well as other limiting conditions were analyzed. Finally, with the analysis of static and dynamic stresses and the calculation by using formulas more overall methods of stress analysis and fracture assessment for thermo-wells, by which the damage and rupture of thermo-wells can be avoided, were presented.