On the analysis of burst capacity of steel strip reinforced flexible pipe with swaging endfitting

ABSTRACT

The objective of this paper is to study the burst capacity of steel strip reinforced flexible pipe (steel strip PSP) with swaging endfitting, in the situation that the burst point is in pipe-endfitting joint area. Experiment was conducted and an analytical model based on thin-wall cylindrical shell theory was proposed. Hoop stress in local coordinate on the innermost reinforcement layer is introduced to predict the burst strength of the pipe, as the hoop stress on this layer in pipe-endfitting joint area increases, the strain on the same layer in the area far away (x→∞) from endfitting is extracted and the corresponding internal pressure can be then obtained. Results of the theoretical model compare well with experimental data. Study shows that Diameter to thickness ratio of pipe (D/t ratio) may affect the SCE in pipe-endfitting joint area. Some useful conclusions are drawn for the design and application of steel strip PSP.

KEYWORDS:

• Flexible pipe
• endfitting
• stress concentration effect
• thin-wall cylindrical shell theory
• burst capacity

Acknowledgements

The author would also express gratitude to Ningbo OPR. Inc to help conduct the pipe burst test.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by “Pioneer” and “Leading Goose” R&D Program of Zhejiang [grant number 2022C03179]; Science and Technology Program of the State Administration for Market Regulation [grant number 2019MK032].