不同管径预制直埋保温管保温层摩擦力研究

Research on Different Diameters Prefabricated Buried Insulating Pipe Insulation Friction

文中以胡克定律和材料热物理性质为出发点,利用经典力学和材料力学的分析方法,从理论上推导出保温层摩擦力的计算公式,并采用不同管径的预制保温管分冬夏两季进行实验验证。理论分析和实验结果表明:当管道受热伸长时,无保温钢管伸长量大于有保温钢管伸长量,即保温层对钢管有很大摩擦作用。若实验过程中假设钢管的弹性模量和钢材的弹性模量相等且为常数,则保温层摩擦力和无保温管与有保温管伸长量之差成正比;温差越大,无保温管与有保温管伸长量之差越大,则保温层摩擦力越大;保温层摩擦力在管道受热膨胀时,能很好地抵消热膨胀力,可以有效地限制管道沿轴向伸长,提高了供热直埋管道的安全性。

Hooke-s law and thermal physical properties was used as a starting point, using analytical methods of classical me-chanics and material mechanics theory formula for calculating the friction of the insulation layer and using different diameters ofprefabricated pipe insulation in winter and summer experiment verification. Theoretical analysis and experimental results show thatwhen the pipe thermal elongates, the no insulation tube elongation is longer than insulation pipe, it means that the insulation hasgreat friction effect. The experiment is assumed that the elastic modulus of the steel pipe is equal and constant. The insulation layerfriction is proportional to the difference between the length of the insulated pipe and the length of pipe without insulation. The moretemperature difference is,the more difference between the length of the insulated pipe and the length of pipe without insulation is,and the more insulation friction is. Insulation friction when the pipe thermal expands can well counteract thermal expansion forceswhich can effectively restrict the pipeline along the axial elongation, thus improving safety of buried heating pipe.