Lateral Buckling and Walking Design of a Pipeline Subjected to a High Number of Operational Cycles on Very Uneven Seabed

2014 ◽  
Author(s):  
Rafael F. Solano ◽  
Bruno R. Antunes ◽  
Alexandre S. Hansen ◽  
T. Sriskandarajah ◽  
Carlos R. Charnaux ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Structural Integrity ◽  
Mechanical Design ◽  
Lateral Buckling ◽  
Element Analysis ◽  
Control Approach ◽  
Temperature Conditions ◽  
Oil Export ◽  
Global Buckling

Global buckling is a behavior observed on subsea pipelines operating under high pressure and high temperature conditions which can jeopardize its structural integrity if not properly controlled. The thermo-mechanical design of such pipelines shall be robust in order to manage some uncertainties, such as: out-of-straightness and pipe-soil interaction. Pipeline walking is another phenomenon observed in those pipelines which can lead to accumulated displacement and overstress on jumpers and spools. In addition, global buckling and pipeline walking can have strong interaction along the route of a pipeline on uneven and sloped seabed, increasing the challenges of thermo-mechanical design. The P-55 oil export pipeline has approximately 42km length and was designed to work under severe high pressure and high temperature conditions, on a very uneven seabed, including different soil types and wall thicknesses along the length and a significant number of crossings. Additionally, the pipeline is expected to have a high amount of partial and full shutdowns during operation, resulting in an increase in design complexity. During design, many challenges arose in order to “control” the lateral buckling behavior and excessive walking displacements, and finite element analysis was used to understand and assess the pipeline behavior in detail. This paper aims to provide an overview of the lateral buckling and walking design of the P-55 oil export pipeline and to present the solutions related to technical challenges faced during design due to high number of operational cycles. Long pipelines are usually characterized as having a low tendency to walking; however in this case, due to the seabed slope and the buckle sites interaction, a strong walking tendency has been identified. Thus, the main items of the design are discussed in this paper, as follows: lateral buckling triggering and “control” approach, walking in long pipelines and mitigate anchoring system, span correction and its impact on thermo-mechanical behavior.

Structural Integrity and Mechanical Design of a Probe of High Pressure and High Temperature for Oil Wells Applying Finite Elements Tools

2014 ◽  
Author(s):  
Erik Rosado Tamariz ◽  
Rito Mijarez Castro ◽  
Agustín Javier Antúnez Estrada ◽  
Alfonso Campos Amezcua ◽  
David Pascacio Maldonado ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Structural Integrity ◽  
Mechanical Design ◽  
Pressure Vessels ◽  
Oil Wells ◽  
Principal Stresses ◽  
Commercial Code ◽  
And Performance ◽  
Mechanical Elements

Measurement of high pressure and high temperature (HPHT) tools is regularly carried out in the hydrocarbons sector to determine not only the characteristics and performance of fluids inside the well, but also to evaluate the mechanical condition of the pipes and the automation of production. The mechanical features of these tools are significantly influenced by the mechanical design of the structure, which eventually affects their performance and integrity. This paper describes the design process and the analysis of the structural integrity of a HPHT measuring tool for oil wells in its sensors section. The classical theories of mechanical design and specifications of the ASME boilers and pressure vessels code were used. The study is performed for several operation variables in a numerical model using a commercial code of finite element method to determinate the maximum principal stresses, total displacements and safety factor in the mechanical elements that form the device. The numerical results were compared with the experimental data source from the laboratory tests.

Upheaval Buckling Analysis of Partially Buried Pipeline Subjected to High Pressure and High Temperature

2011 ◽  
Author(s):  
Jason Sun ◽  
Han Shi ◽  
Paul Jukes
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Soil Cover ◽  
Resistance Force ◽  
Soil Resistance ◽  
Buried Pipeline ◽  
Buried Pipelines ◽  
Lateral Buckling ◽  
Upheaval Buckling ◽  
Global Buckling

Offshore industry is now pushing into the deepwater and starting to face the much higher energy reservoir with high pressure and high temperature. Besides the significant impacts on the material, strength, and reliability of the wellhead, tree, and manifold valve; high Pressure (HP) also leads to thicker pipe wall that increases manufacturing and installation cost. High Temperature (HT) can have much wider impact on operation since the whole subsea system has to be operated over a greater temperature range between the non-producing situations such as installation, and long term shut down, and the maximum production flow. It is more concerned for fact that thicker wall pipe results in much greater thermal load so to make the pipeline strength and tie-in designs more challenging. Burying sections of a HPHT pipeline can provide the advantages of thermal insulation by using the soil cover to retain the cool-down time. Burial can also help to achieve high confidence anchoring and additional resistance to the pipeline axial expansion and walking. Upheaval buckling is a major concern for the buried pipelines because it can generate a high level of strain when happens. Excessive yielding can cause the pipeline to fail prematurely. Partial burial can have less concern although it may complicate the pipeline global buckling behavior and impose challenges on the design and analysis. This paper presents the studies on the upheaval buckling of partially buried pipelines, typical example of an annulus flooded pipe-in-pipe (PIP) configuration. The full-scale FE models were created to simulate the pipeline thermal expansion / upheaval / lateral buckling responses. The pipe-soil interaction (PSI) elements were utilized to model the relationship between the soil resistance (force) and the pipe displacement for the buried sections. The effects of soil cover height, vertical prop size, and soil resistance on the upheaval and lateral buckling response of a partially buried pipeline were investigated. This paper presents the latest techniques, allows an understanding in the global buckling, upheaval or lateral, of partially buried pipeline under the HPHT, and assists the industry to pursue safer but cost effective design.

Evolution of Disordering in SiC under High Pressure High Temperature Conditions: In-situ Powder Diffraction Study

1998 ◽  
Vol 278-281 ◽  
pp. 612-617 ◽  
Author(s):  
Bogdan F. Palosz ◽  
Svetlana Stelmakh ◽  
Stanislaw Gierlotka ◽  
M. Aloszyna ◽  
Roman Pielaszek ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Diffraction Study ◽  
Powder Diffraction ◽  
Temperature Conditions ◽  
High Pressure High Temperature

scholarly journals Laminar Burning Velocities for Methane/Air under High Pressure and High Temperature Conditions

2005 ◽  
Vol 71 (704) ◽  
pp. 1183-1189 ◽  
Author(s):  
Hiroyuki NISHIDA ◽  
Takuma OGAWA ◽  
Eiji WAKISAKA ◽  
Takeshi TACHIBANA
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Temperature Conditions

Evaluation of Design Premises and Uncertainties on the Thermo-Mechanical Behavior of a Subsea Pipeline

2014 ◽  
Author(s):  
Bruno Reis Antunes ◽  
Rafael Familiar Solano ◽  
Alexandre Hansen
Keyword(s):  
Formation Process ◽  
Mechanical Design ◽  
Design Stage ◽  
Stress And Strain ◽  
Lateral Buckling ◽  
Friction Factors ◽  
Global Buckling ◽  
Pipeline Route ◽  
Seabed Bathymetry ◽  
Subsea Pipelines

Buckle formation process is a key subject for the design of subsea pipelines laid on the seabed and operating under high pressure and high temperature (HP/HT) conditions. When the controlled lateral buckling methodology is adopted triggers are placed along pipeline route in order to increase the buckle formation probability in specific locations, sharing pipeline expansion between these sites and reducing the level of stress and strain in each buckle. Despite of its importance, buckle formation process is influenced by several parameters such as the seabed bathymetry, engineered triggers, lateral out-of-straightness (OOS) and pipe-soil interaction. While the first two items above can be defined with reasonable accuracy at previous stages of design, lateral OOS will only be known with tolerable confidence after pipeline installation. The level of uncertainty related to pipe-soil interaction is also considerable since pipeline embedment and friction factors are estimated using equations that include empirical correlations and field collected data. In addition these parameters are influenced by the installation process. Due to these uncertainties, conservative premises are usually assumed in order to obtain a robust pipeline thermo-mechanical design. After pipeline installation and/or start of operation an investigation can be performed in order to confirm the assumptions considered in the design. This paper presents a comparison of premises adopted during design stage of a pipeline based on the controlled lateral buckling methodology and the feedback obtained with the post-lay survey performed. After a brief introduction, pipeline embedment, global buckling at crossings, lateral OOS and sleepers’ height are some of the subjects addressed. Finally, conclusions and recommendations are presented in order to support future similar projects.

High-Pressure Synthesis, Crystal Structure, and Properties of the New Orthorhombic Rare-Earth meta-Oxoborates RE(BO2)3 (RE = Dy – Lu)

2004 ◽  
Vol 59 (2) ◽  
pp. 202-215 ◽  
Author(s):  
Holger Emme ◽  
Tanja Nikelski ◽  
Thomas Schleid ◽  
Rainer Pöttgen ◽  
Manfred Heinrich Möller ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Ambient Pressure ◽  
Structure And Properties ◽  
Crystal Data ◽  
Temperature Conditions ◽  
Pressure Synthesis ◽  
Ir Spectroscopic ◽  
Pressure Phase

The new orthorhombic meta-oxoborates RE(BO2)3 (≡REB3O6) (RE = Dy-Lu) have been synthesized under high-pressure and high-temperature conditions in a Walker-type multianvil apparatus at 7.5 GPa and 1100 °C. They are isotypic to the known ambient pressure phase Tb(BO2)3, space group Pnma. In contrast to Dy(BO2)3, which was also obtained in small amounts under high-temperature conditions, the preparation of the higher orthorhombic homologues RE(BO2)3 (RE = Ho-Lu) was only possible using high-pressure. The meta-oxoborates RE(BO2)3 (RE = Dy-Er) were synthesized as pure products, whereas the orthorhombic phases with RE = Tm-Lu were only obtained as byproducts. With the exception of Yb(BO2)3 it was possible to establish single crystal data for all compounds. The results of temperature-resolved in-situ powder-diffraction measurements, DTA, IR-spectroscopic investigations, and magnetic properties are also presented.

Sign in / Sign up

Export Citation Format

Share Document