PSI - Issue 40

A.G. Khakimov et al. / Procedia Structural Integrity 40 (2022) 214–222 A.G. Khakimov / StructuralIntegrity Procedia 00 (2022) 000 – 000

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between the supports, the acceptable amplitude of arched ejection tends to increase. Fig. (b) gives the dependences of the acceptable amplitude W n of arched ejection on the internal pressure p i 0 in the pipeline for different distances between the supports L = 100, 150, 200 m (solid, dashed and dotted lines, respectively) regarding the yield point of the pipeline material σ t = 200 MPa. As it is seen, with an increase in internal pressure of the pipeline, the acceptable amplitude of arched ejection tends to be reduced.

(a)

(b)

Fig. 4. Dependences of the acceptable amplitude W n of arched ejection for different distances between the supports L = 100, 150, 200 m (solid, dashed and dotted lines, respectively): (а) on the yield point σ t ; (b) on the internal pressure in the pipeline p i 0 . If there is a loss of stability and the amplitude of arched ejection is less than the acceptable amplitude determined according to formula (13), the effective axial load in the pipeline is found according to formula (10). 6. Conclusions Bending stiffness, tensile forces and external hydrostatic pressure stabilize the pipeline, and the compression forces, internal hydrostatic pressure, fluid motion at any velocity inside the pipeline and increase in the pipe wall temperature destabilize it. With an increase in the yield point of the pipeline material and the distance between the supports, the acceptable amplitude of arched ejection increases as well. With an increase in the internal pressure of the pipeline, the acceptable amplitude of arched ejection tends to be reduced. The obtained results enable us to analyze the stability of pipeline systems. These results can be applied to analyzing static stability of the pipeline at the stage of design, performance and elimination of arched ejections. Acknowledgements The work was supported by the state budget for the state task (No. 0246-2019-0088). References Aynbinder A.B., Kamershteyn A.G., Calculation of trunk pipelines for strength and stability, Nedra, Moscow, 1982. Babin L.A., Bykov L.I., Volokhov V.Ya., Routine calculations in pipeline construction, Nedra, Moscow, 1979. Bolshakov A.M., Burnashev A.V., 2015. Investigation into the stress-deformed state of a bent segment in the main gas pipeline. In: Safety and viability of technical systems, Materials and Reports, In 3 vols. 98 – 102. Borodavkin P.P., Berezin V.L., Construction of trunk pipelines, Nedra, Moscow, 1977. Chuchkalov M.V., Gumerov K.M., 2014. Simulation of stress-strain state in subsurface pipeline with account for ground changes. Transportation and Storage of Oil Products and Hydrocarbon Raw Materials, 2, 3 – 6. Dimov L.A., Bogushevskaya E.M., Trunk pipelines under conditions of bogs and flooded areas, Gornaya Kniga: Izdatelstvo Moskovskogo gosudarstvennogo gornogo universiteta, Moscow, 2010. Gumerov K.M., Silvestrov S.A., 2017. On the assessment of trunk pipeline longitudinal stability. Problems of Gathering, Treatment and Transportation of Oil and Oil Products, 1 (107), 60-68. Ilgamov M.A., 2018. Interaction between Euler, Helmholtz and Rayleigh instabilities. Technical Physics, 63(2), 163 – 167.