Creep rupture behaviour of circumferentially welded mod. 9Cr–1Mo steel pipe subject to internal pressure and axial load

Pipelines residing on the seabed are exposed to various hazards, one of them being denting, hooking and release of the pipeline by e.g. anchors or trawl gear. As a pipeline is displaced transversely in a hooking event, an axial tensile load resisting the displacement builds up in the pipeline. This study examines the effect of applying three different axial loads (zero, constant, and linearly increasing) to a pipe while simultaneously deforming it transversely. A fairly sharp indenter conforming to the prevailing design codes was used to deform the pipes. These three tests were repeated with an internal pressure of about 100 bar for comparison. Adding an axial load appeared to increase the pipe’s stiffness in terms of the force-displacement curve arising from deforming the pipe transversely. The internal pressure also increased the stiffness, and produced a more local dent in the pipe compared with the unpressurised pipes. All tests were recreated numerically in finite element simulations. Generally, the results of the simulations were in good agreement with the experiments.

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413 Creep Rupture Life of Longitudinally Welded Pipe with Half Elliptic Defect at Outer Surface subject to Internal Pressure

Proceedings of the 1992 Annual Meeting of JSME/MMD ◽

10.1299/jsmezairiki.2005.0_279 ◽

2005 ◽

Vol 2005 (0) ◽

pp. 279-280

Author(s):

Tetsuo Teramae

Keyword(s):

Internal Pressure ◽

Outer Surface ◽

Rupture Life ◽

Creep Rupture ◽

Welded Pipe ◽

Elliptic Defect

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A biaxial fatigue testing machine for thin-walled tubes under axial load and internal pressure at elevated temperatures Soret, N., Bernadou, J.-P. and Marsac, S. Proc. 4th Int. Conf. on Biaxial/Multiaxial Fatigue II, St. Germain en Laye, France, 31 May–3 June 1994, pp. 221–232

International Journal of Fatigue ◽

10.1016/s0142-1123(97)87158-7 ◽

1996 ◽

Vol 18 (8) ◽

pp. 609

Keyword(s):

Internal Pressure ◽

Axial Load ◽

Elevated Temperatures ◽

Fatigue Testing ◽

Testing Machine ◽

Multiaxial Fatigue ◽

Biaxial Fatigue ◽

Thin Walled

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Buckling of Double Bellows Expansion Joints under Internal Pressure

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1964_006_040_02 ◽

1964 ◽

Vol 6 (3) ◽

pp. 270-277 ◽

Cited By ~ 8

Author(s):

D. E. Newland

Keyword(s):

Internal Pressure ◽

Axial Load ◽

Expansion Joint ◽

Expansion Joints ◽

Supporting Structure ◽

Universal Expansion ◽

Critical Buckling Pressure

Corrugated bellows expansion joints may buckle under internal pressure in the same way as an elastic strut may buckle under an axial load. This paper is concerned with the analysis of this phenomenon for the ‘universal expansion joint’ which incorporates two bellows joined by a length of rigid pipe. The principal conclusion is that, by providing a correctly designed supporting structure, the critical buckling pressure can be increased to up to four times its value for the same system with no supports.

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