Analysis of the stress-strain state of an air crossing of pipeline in the course of repair

Abstract

We propose a procedure for the numerical analysis of the stress-strain state and criteria of its admissible state in the course of repairs of the air crossings of gas mains with regard for possible defects of the pipe metal. Using the "3D PipeMaster" software complex, we compute different versions and present recommendations concerning the optimal location of pipe-laying machines with an aim of realization of the possibility of lifting the pipe to a height required for repair works with guaranteed validity of the prescribed conditions of strength. The values of tractive forces in the pipe-laying machines are determined. The optimal sites of fixing the pipeline in the transverse direction are indicated and the corresponding forces acting in the cables used to prevent the transverse motions of the pipeline are calculated.

Numerical model of interaction of a mobile lift chain with a main gas pipeline pipe in the process of repair work

“…Such mobile lifting devices can be used to repair support nodes of pipelines with a diameter of up to 1020 mm. The peculiarity of lifting large-diameter pipelines above the base plate is the significant mass of two adjacent pipeline runs and the high bending stiffness of largediameter pipes, which ultimately requires a large lifting force [46,49].…”

Analytical model of oil pipeline overground transitions, laid in mountain areas

“…At the same time, the transitions of main pipelines are high-loaded constructions, because they are designed with lower strength factors than strength factors for other industries in order to decrease material usage [3]. Therefore, all essential factors that influence on the behavior of the oil pipeline during its operation should be considered within pipeline designing or calculating of strength and stiffness [4].…”

Analytical model of the strength of overhead transitions of oil pipelines built in mountainous areas

“…Вони виявились найдешевшими щодо проведення будівельних робіт та простими і зручними в експлуатації [1,2]. Разом з цим переходи магістральних трубопроводів -це високонавантажені конструкції, оскільки ще на етапі проєктування з метою економії матеріалу в них закладаються досить низькі, порівняно з іншими галузями, коефіцієнти запасу міцності [3]. Тому при проєктувальних чи оцінкових розрахунках на міцність та жорсткість слід прагнути урахувати всі суттєві фактори, які впливають на поведінку переходу нафтопроводу під час його експлуатації [4].…”