Strain-based Monitoring Parameter Study on Steel Strip Reinforced Thermoplastic Pipe (SSRTP) under Internal Pressure

The mechanical behaviors of steel strip–reinforced flexible pipe (steel strip PSP) under combined axial extension → internal pressure ( T→ P) load path were investigated. Typical failure characteristics of pipe samples under pure internal pressure and T→ P load path were identified in the full-scale experiments. A theoretical model for pipe under tension load was proposed to capture the relationship between axial extension of the pipe body and stress state of the steel strip. Numerical study based on finite element (FE) method was conducted to simulate the experiment process, and good agreement between FE data and experiment results were observed. Sensitivity study was conducted to study the effect of some key parameters on the pipe antiburst capacities in T→P load path; the effect of preloaded internal pressure on the pipe tensile capacity in P→T load path was also studied. Useful conclusions were drawn for the design and application of the steel strip PSP.

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Theoretical Modeling of Steel Strip Reinforced Flexible Pipe With Swaging End Fitting by Taking Into Account Stress Concentration Effect

Volume 5A: Pipelines, Risers, and Subsea Systems ◽

10.1115/omae2019-95462 ◽

2019 ◽

Author(s):

Yifan Gao ◽

Wei Chen ◽

Yong Bai

Keyword(s):

Stress Concentration ◽

Internal Pressure ◽

Steel Strip ◽

Displacement Discontinuity ◽

Concentration Effect ◽

Elastic Model ◽

Thin Wall ◽

Burst Strength ◽

Joint Area ◽

Stress Concentration Effect

Abstract A new theoretical model was proposed to calculate the burst pressure of steel strip reinforced flexible composite pipes (steel strip PSP) based on the thin wall cylindrical shell theory and the squeeze pressure expression between layers was derived. The radial displacement discontinuity of pipe wall in pipe-end fitting joint area takes in account in this model which could result in Stress Concentration Effect (SCE) in reinforcement layers. The SCE is caused by swaging end fitting clamped tightly at the end of the pipe. The result of the hoop strain in the joint area calculated by this model is greater than the one calculated by the classic elastic model, which leads to relative conservative burst strength of the pipe. The hoop stress variation via internal pressure on innermost reinforcement layer is introduced to predict the burst strength of the pipe. As the stress in the joint area reaches its ultimate strength, the strain on the same layer in the point far away from this area (x→∞) is extracted and the corresponding internal pressure is obtained as the burst strength of the pipe. The calculated data from two models were compared with the experiment results and the proposed new model showed better accuracy than the classic elastic model. Final additional parametric studies were conducted, while the effect of the pipe diameter, the winding angle, the number and thickness of the reinforcement layer on the burst strength of the pipe were studied. Useful conclusions were drawn for the design and application of the steel strip PSP in offshore engineering.

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Lateral Buckling Response of Subsea HTHP Pipelines Using Finite Element Methods

Volume 4A: Pipeline and Riser Technology ◽

10.1115/omae2013-10585 ◽

2013 ◽

Cited By ~ 1

Author(s):

M. Masood Haq ◽

S. Kenny

Keyword(s):

Internal Pressure ◽

Operating Temperature ◽

Complex Function ◽

External Pressure ◽

Parameter Study ◽

Embedment Depth ◽

Lateral Buckling ◽

Structural Support ◽

Global Buckling ◽

Subsea Pipelines

Subsea pipelines are subject to load effects from external hydrostatic pressure, internal pressure, operating temperature, ambient temperature and external reactions (e.g. seabed, structural support). These parameters influence the effective axial force that governs the pipeline global buckling response. Other factors, including installation stress, seabed slope, soil type, and embedment depth, can influence the pipe effective force. Pipelines laid on the seabed surface or with limited embedment may experience lateral buckling. The resultant mode response is a complex function related to the spatial variation in these parameters and kinematic boundary conditions. In this paper, results from a parameter study, using calibrated numerical modelling procedures, on lateral buckling of subsea pipelines are presented. The parameters included pipe diameter to wall thickness (D/t) ratio, pipe out of straightness (OOS), operating temperature and internal pressure, external pressure associated with the installation depth, and seabed lateral and axial friction properties.

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Constitutive Modeling of Porcine Coronary Arteries Using Designed Experiments

Journal of Biomechanical Engineering ◽

10.1115/1.1560138 ◽

2003 ◽

Vol 125 (2) ◽

pp. 274-279 ◽

Cited By ~ 7

Author(s):

Stacey A. Dixon ◽

Russell G. Heikes ◽

Raymond P. Vito

Keyword(s):

Coronary Artery ◽

Internal Pressure ◽

Coronary Arteries ◽

Axial Strain ◽

Constitutive Models ◽

Parameter Study ◽

Dependent Variables ◽

Measured Force ◽

The Difference ◽

Constitutive Parameters

The development of new coronary artery constitutive models is of critical importance in the design and analysis of coronary replacement grafts. In this study, a two-parameter logarithmic complementary energy function, with normalized measured force and internal pressure as the independent variables and strains as the dependent variables, was developed for healthy porcine coronary arteries. Data was collected according to an experimental design with measured force ranging from 9.8 to 201 mN and internal pressure ranging from 0.1 to 16.1 kPa (1 to 121 mmHg). Comparisons of the estimated constitutive parameters showed statistically significant differences between the left anterior descending [LAD] and right coronary artery [RCA], but no differences between the LAD and left circumflex [LCX] or between the LCX and RCA. Point-by-point strain comparisons confirm the findings of the model parameter study and isolate the difference to the axial strain response. Average axial strains for the LAD, LCX, and RCA are 0.026±0.009,0.015±0.005, and 0.011±0.009, respectively, at all physiologic loads, suggesting that the axial strains in the LAD are significantly higher than in the other regions.

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Analysis of steel strip reinforced thermoplastic pipe under internal pressure

Ships and Offshore Structures ◽

10.1080/17445302.2015.1063470 ◽

2015 ◽

Vol 11 (7) ◽

pp. 766-773 ◽

Cited By ~ 6

Author(s):

Yong Bai ◽

Wei Chen ◽

Haichao Xiong ◽

Hongdong Qiao ◽

Huibin Yan

Keyword(s):

Internal Pressure ◽

Steel Strip

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Stresses in reinforced nozzle-cylinder attachments under internal pressure loading analyzed by the finite-element method: a parameter study. [PWR and BWR]

10.2172/5452134 ◽

1977 ◽

Cited By ~ 1

Author(s):

J.W. Bryson ◽

W.G. Johnson ◽

B.R. Bass

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Internal Pressure ◽

Parameter Study ◽

The Finite Element Method ◽

Pressure Loading ◽

Element Method

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Study of operating properties of aanticorrosion packing papers

Ferrous Metallurgy Bulletin of Scientific Technical and Economic Information ◽

10.32339/0135-5910-2020-10-1021-1027 ◽

2020 ◽

Vol 76 (10) ◽

pp. 1021-1027

Author(s):

A. P. Ponomarev ◽

L. G. Kolyada ◽

E. V. Tarasyuk

Keyword(s):

Steel Strip ◽

Low Carbon Steel ◽

Strength Characteristics ◽

Low Carbon ◽

Operating Characteristics ◽

Packing Materials ◽

Accelerated Corrosion ◽

Operating Properties ◽

Deformation And Strength Characteristics ◽

Anticorrosion Properties

Metal products are subjected to atmospheric corrosion during transportation and storing. An important way to prevent this negative phenomenon is application of special packing materials, in particular materials, containing volatile inhibitors of corrosion, which protect metal against various corrosion agents. To protect metal effectively it is necessary to provide a definite level of operating characteristics of packing materials. The purpose of the work was the study of operating properties of inhibited crepe, inhibited and laminated polyethylene film, inhibited crepe and reinforced by polypropylene web papers, manufactured by OJSC “PP TechnoKhim”, Magnitogorsk, used for packing of metals. Structural and dimensional, sorption, deformation and strength characteristics, of the studied anticorrosion papers are presented, the characteristics being calculated based on the results of measurements. To determine their physical-mechanical and anticorrosion properties, standard methods and methodologies were used. To evaluate impact of moisture and transportation conditions, indices of water adsorption and wear of the studied papers were determined. Inhibitor content in these materials was determined by thermogravimetric analysis method. Their protective ability was studied on samples of low carbon steel strip. For accelerated corrosion tests the strip samples were degreased by alcohol, dried in air and packed in the studied anticorrosion papers, after that they were exposed under increased temperatures and moisture conditions. It was determined, that among the materials under the study, the inhibited crepe paper, reinforced by polypropylene web, hhas the best complex of physical-mechanical and anticorrosion properties. It provides a higher level of prevention corrosion of metal l and surpasses other materials in a number of deformation and strength characteristics. Recommendations were proposed to improve qquality of produced anticorrosion papers.

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