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ABSTRACT While it is common to check the toughness of steels at a single design temperature and by a single method as part of qualification for service, it is much rarer to perform tests at multiple temperatures and by multiple test methods to compare the performance. This work was performed on an X70 pipe suitable for offshore pipeline service with results obtained in Charpy, CTOD toughness in bending, and CTOD toughness in tension. INTRODUCTION Subsea equipment in the form of steel forgings and pipe is often used in conditions where the lowest design temperature (LDT) is lower than the lowest anticipated service temperature (LAST) in a steady state condition, due to transients such as blowdown. Blowdown events, when pressurized gas is evacuated into low pressure regions, can happen multiple times during system operation. When the steel is qualified with toughness tests at LAST, the safety factor against brittle fracture will be reduced at the LDT, all other things being equal, due to the ductile-to-brittle transition of steels. Since LAST and LDT will vary from situation to situation, this program shifts to considering the steel material behavior in the lower transition region, where both the numerical variability of toughness as CTOD and the behavior variability defined in terms of delta c, delta u, and delta m are important. These behavior descriptions indicate, respectively, little or no tearing, limited tearing or pop-in extension, and reaching the maximum load of the toughness specimen smoothly. Qualifying for LAST may for instance require a CTOD of 0.5 mm (0.020 in.) and delta u or delta m behavior at that temperature. Safety factors may be built into the assessment of the situation at LDT and after an LDT event in three ways that will be assessed in this program. The first is that the constraint difference between standard material qualification bend toughness tests and in-service tension loading can mean that realistic service tension loadings actually have higher toughness material behavior that avoid the more brittle behavior modes. The second is that the material toughness CTOD value can increase sufficiently based on the constraint that tension cases can be assessed with the higher toughness values, regardless of the behavior mode. The third is that crack advance during a low-temperature transient can inhibit future crack growth by fatigue, rather than exacerbate it.
- Energy > Oil & Gas (0.66)
- Materials > Metals & Mining > Steel (0.48)
- Well Completion > Hydraulic Fracturing (1.00)
- Production and Well Operations (0.74)
Cross-Weld Tensile Strength of Aluminum Alloys en AW 5083 and 6082
Nyhus, Bård (SINTEFMaterials and Chemistry) | Dumoulin, Stephane (SINTEFMaterials and Chemistry) | Nordhagen, Håkon (SINTEFMaterials and Chemistry) | Midling, Ole Terje (Marine Aluminium AS) | Myhr, Ole Runar (Hydro Aluminium) | Furu, Trond (Norsk Hydro ASA) | Lundberg, Steinar (Hydal Aluminium Profiler AS)
ABSTRACT Aluminium is known as a safe and suitable material for offshore installations. Factors that favour aluminium are low weight, no need for surface treatment and low maintenance costs. Though aluminium has a high strength-to-weight ratio, it suffers from strength reduction in heat affected zones when welded. The strength of the soft zones is often dimensioning in design, and the ability to predict the strength reduction is important for fully utilizing the potential of aluminium as a structural material. In the current study, the cross weld strength of EN AW 6082-T6 and EN AW 5083-H321 as a function of wall thickness at room temperature and at −60°C ("arctic temperature") was tested. The main objectives were to verify that the materials and the weldments are not deteriorated at low temperatures, and to check if using additional reduction factors for the heat affected zones for plates and extrusions thicker than 15 mm as specified in the design standard EN 1999–1–1 is correct. The results show that there is no reduction in strength for low temperatures, nor for plates and extrusions thicker than 15 mm. Based on the results in this study, changes in EN 1999–1–1 are recommended. INTRODUCTION Unlike body-centred cubic (BCC) metals, the yield and strength temperature sensitivity of face-centred cubic (FCC) materials, such as aluminium (Al) alloys, is negligible when lowering the temperature below room temperature (Hertzberg 1996). Because of the high specific strength, good corrosion resistance and good mechanical properties at low temperature, Al-alloys are often used for low temperature conditions such as cryogenic applications (e.g. Liquefied Natural Gas (LNG) tanks and space/aeronautics). Thus, the low temperature characterization found in the literature focus on test temperatures far below −60°C. In BCC materials, such as steels, the dislocation width is narrow and the Peierls stress increases rapidly with decreasing temperature, thus the yield stress will increase strongly with decreasing temperature. An important consequence of this for BCC materials is that the yield stress can rise to such high levels that only a very limited plastic zone ahead of a crack will occur before unstable (brittle) fracture results. This material brittleness will not occur in FCC alloys (Aluminium), and a ductile fracture mode will prevail.
- Materials > Metals & Mining > Aluminum (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Well Completion > Hydraulic Fracturing (1.00)
- Facilities Design, Construction and Operation > Natural Gas Conversion and Storage > Liquified natural gas (LNG) (0.54)
ABSTRACT Four offshore steels consisting of two forgings and two plates have been tested for both Charpy transition behavior and for CTOD transition behavior. Charpy transition results for the F22 provided a smooth transition curve with the most variability in energy near the middle of the transition. The other three steels showed a different behavior, where the highly ductile behavior and the much more brittle behavior could be found at the same temperature on repeat specimens over a limited temperature range. The range of CTOD behavior for API 2Y Grade 60 plate is large enough that the Master Curve distribution does a poor job of covering the entire range of behavior and one of the inhomogeneous Master Curve methods would better describe the results. The CTOD results from the other three steels have less variability, but each has a different temperature shift compared to the Charpy transition, so these results do not appear to allow any tightening of that relationship compared to existing Master Curve models. INTRODUCTION The Master Curve approach, developed by Wallin (1989) and included in BS 7910 Annex J (2015), provides a lower bound estimate of fracture toughness (Kmat) from Charpy V-notch (CVN) test data for steels. This approach, being developed over 25 years ago, could possibly be providing over-conservative Kmat values when used on modern steel forgings and structural steel. The basis for the Master Curve correlation with CVN data has been well established for nuclear steels and thin, higher strength steels, but not for thicker modern steels commonly used in the offshore industry today. This program has been designed to collect data on which new Kmat - CVN correlations can be checked, using data from current steels used in the oil & gas industry, with particular attention to structural and forging steels. Primary steels of interest were forging materials such as F22, 4130, A707, and 8630 and offshore structural steels such as 2W and 2Y in both grades 50 and 60. EWI was able to source material for some of these grades, including materials already at EWI.
Industrial Application of SENT and Segment Testing on Deepwater Buckle Arrestor Assembly Installed by S-Lay
Fonzo, Andrea (Centro Sviluppo Materiali) | Porta, Riccardo (Centro Sviluppo Materiali) | Selker, Ruud (INTECSEA) | Liu, Ping (INTECSEA) | Jurdik, Erich (South Stream Transport BV) | Chaudhuri, Jay (South Stream Transport BV)
ABSTRACT For a major deepwater pipeline project in the Black Sea, Buckle Arrestors will be deployed to prevent catastrophic buckle propagation in the event of collapse. Buckle Arrestor Assemblies (BAAs) will be installed using the S-lay pipeline installation method, then introducing cyclic plastic strain on the BAAs' girth welds during their passage over stinger's rollers. Fracture during installation is one of the potential failure modes for the girth weld. A material testing and assessment program has been launched at Centro Sviluppo Materiali (Italy) aimed at evaluating the impact of in-field strain sequence on a defected girth weld. The program was articulated in the evaluation of toughness by using single-specimen method with compliance technique on large thickness SENT samples. Then cyclic tearing sequence has been applied on Segment specimens with increased daylight length, aimed at reproducing the real pipe remote strain conditions by small-to-medium scale testing. Accompanying the testing program, a series of ECA calculations has been performed to investigate the robustness of the segment testing methodology used to evaluate the resistance of flawed pipes when subjected to tearing plus cycling loading scenario. As a main conclusion, the segment with increased daylight methodology has been found robust. It has been confirmed by comparison of experimental results and ECA pipe solutions provided by both BS 7910 and API 579. INTRODUCTION South Stream Transport BV (SSTTBV) is developing a major gas transmission system comprising up to four (4) pipeline strings to be installed in water depths up to 2200 m. The full system will have a massive capacity to transport 63 billion cubic metres (bcm) of natural gas per annum, over a distance of more than 900 km through the Black Sea. The pipeline outside diameter (D) will be 32-inch and its wall thickness (t) 39 mm. The material grade of the line pipe is DNV SAWL 450 SFDU and, depending on the supplier, is manufactured using either UOE or JCOE method. This project can be considered as one of the most challenging pipeline projects ever, stretching the limits of present-day industry. In order to prevent catastrophic propagation of a buckle in the unlikely event of pipeline collapse, inline structures (Buckle Arrestors, BAs) are deployed at certain spatial intervals when the water depth exceeds that equivalent to the buckle propagation pressure for the pipeline. The BAs were designed and sized according to offshore design standard DNV-OS-F101 (2010). The BAA consists of three parts, i.e. one machined thick (BA) section girth welded between two pup pieces manufactured from line pipe sections of nominal dimensions. Material grade is the same for the BA section and the adjacent pup pieces, i.e. DNV SAWL 450 SFDU. However, BA and pup pieces were subjected to different thermal history. Fig. 1 schematically presents the inline Buckle Arrestor Assembly (BAA) that will be deployed in the pipeline project.
- Europe (1.00)
- North America > United States (0.68)
- Well Completion > Hydraulic Fracturing (1.00)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Offshore pipelines (1.00)
Prediction of CTOD Based on GE/EPRI for Pipes With a Semi-Elliptical Surface Crack Under Global Bending
Jang, Youn-Young (Seoul National Univ. of Science and Technology) | Huh, Nam-Su (Seoul National Univ. of Science and Technology) | Lee, Jae-Bin (Steel Solution Center) | Kim, Ki-Seok (Steel Solution Center) | Cho, Woo-Yeon (Steel Solution Center)
ABSTRACT For many structural components in oil and gas transmission pipelines, fracture assessment is one of essential elements for structural integrity since a common failure arises from internal cracks mostly formed during installation or operation in severe environment. In the fracture assessment for pipeline, the fracture mechanics parameters. i.e., J- integral and crack-tip opening displacement (CTOD), have been used, in which these parameters can characterize crack initiation and instability well. In particular, CTOD is widely used for fracture assessment in strain-based design (SBD) concept as well as the transportation pipelines or submarine riser industries subject to large deformation. Many researches have been made to estimate fracture parameters, and several engineering approaches such as General Electric/Electric Power Research Institute (GE/EPRI) and reference stress (RS) method have been suggested. Among them, a GE/EPRI method is one of general estimation approaches based on finite element (FE) analysis, where material behavior is assumed to be characterized by the Ramberg-Osgood (R-O) relation. In GE/EPRI approach, plastic influence functions used to calculate fully plastic term of fracture parameter are calibrated through the detailed FE analyses according to geometries and material properties, respectively. In this context, FE analyses should be systematically performed to estimate CTOD for various cracked pipes based on GE/EPRI method. In the present paper, 3-dimensional (3-D) elastic-plastic FE analyses were carried out to calibrate and propose the fully plastic solutions of CTOD based on GE/EPRI concept for pipes with a semi-elliptical surface crack. The geometric and material variables of a cracked pipe such as pipe thickness, crack length and strain hardening exponent were systematically varied to cover practical ranges of these values. In terms of loading condition, pure bending moment which is most important loading mode in pipeline was considered. INTRODUCTION Many pipeline transmission systems have been constructed in all around the world to satisfy the demand for increasing gas and oil as an important energy source and transport safely energy to industry. In the construction industry for transportation pipeline, girth weld procedure has been performed to connect the long-distance pipeline. However, since weld cracking can be created during installation or operation in severe environment (Chiodo and Ruggieri, 2010; Dake et al., 2012), a common failure has been arisen from internal cracks. To secure structural integrity and eliminate uncertainty due to crack initiation, the many crack assessment procedures based on fracture mechanics have been developed. For such a crack assessment, J-integral or CTOD based on elastic-plastic fracture mechanics (EPFM) has been used as fracture parameters to estimate crack driving forces of cracked pipelines. In particular, CTOD has been widely adopted for a crack assessment in SBD concept (Zhang et al., 2014) as well as the transportation pipelines or submarine riser industries subject to large deformation.
- Energy > Power Industry (1.00)
- Energy > Oil & Gas > Midstream (0.69)
- Well Completion > Hydraulic Fracturing (1.00)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Offshore pipelines (0.48)
ABSTRACT This study presents the reliability-based flaw assessment for the crack in the mooring chain of a floating type offshore structure. Flaw assessment procedure of BS7910 was combined with first- and second-order reliability method (FORM, SORM) so that the acceptance of a given flaw can be assessed considering the uncertainties of parameters that play important role in the flaw assessment. Considering the probabilistic nature of the crack size and long-term distribution of the stresses acting on the crack, the failure probability was calculated using FORM and SORM. To check the validity of the FORM and SORM, Monte Carlo simulation was also carried out to derive the true limit state function and compared with the results of FORM and SORM. INTRODUCTION Welded structures are inevitably susceptible to the cracks either at weld toe or within welds due to the variety of reasons, such as excessive residual stress, inclusion of impurities and unexpected lack of fusion and so on. These cracks pose a major threat to the integrity of entire structure during it service life under environmental loadings acting on it such as wind, wave and current loads. Engineering criticality analysis, which targets to assess the fitness for service of the structure during its lifetime, is defined as a fracture mechanics based numerical analysis aiming at the assessment of flaw susceptibility under the loadings that the structure is exposed to. A flaw may fracture, either in brittle or ductile way, due to excessive loading or may grow to the critical size which may lead to successive fracture or functional degradation such as leak. Flaw assessment is critical to both fabricator and operator point of view because a decision needs to be made whether the existing flaw should be repaired or not, which has a huge impact in terms of the CAPEX and OPEX. Flaw assessment procedure is well documented in BS7910 (BSI, 2005) or other equivalent standards such as API (API, 2007). Even though the analysis procedure is fully mature, it lacks the consideration of the probabilistic natures of the analysis parameters such as crack length, depth, fracture toughness, crack growth constants and loading parameters etc. All these parameters are difficult to define in deterministic way due to the complexities involved in, hence the standards take this random effect into account by either relying on partial safety factor or using statistically conservative values, such as mean minus two standard deviation or something equivalent. On the other hand, the reliability concept has been utilized in many engineering field for years targeting the probability based assessment on the structural integrity. The probabilistic nature of analysis parameters may be handled by a Monte Carlo simulation (Metropolis and Ulam, 1949), but large number of sample and corresponding simulation require practically infeasible computational burden. The computation cost increase dramatically especially when the number of random variables exceed 3 or 4 eventually leading to several thousand calculations. To overcome this difficulty, so called first- and second-order reliability concept was developed and successfully applied in many engineering structural problems (Cornell, 1969, Hasofer et al., 1974, Rackwitz and Fiessler, 1978, Fiessler et al., 1979, Breitung, 1984, Hohenbichler et al., 1987, Tvedt, 1990). First- and second order reliability methods rely on Taylor series expansion in joint probability space to approximate the limit state function (LSF) with some truncation errors. First order reliability method (FORM) approximate the limit state function as a hyper-plane in multidimensional space, based upon the limit state value and its gradients in all directions. FORM works fine provided that the LSF is linear or near-linear in the region of interest. When the LSF is not linear enough, the higher order terms need to be included in the Taylor expansion in order to achieve better approximation of LSF. In SORM, second order terms are taken into account so that curvature of LSF is captured providing far better representation of LSF.
- Well Completion > Hydraulic Fracturing (1.00)
- Facilities Design, Construction and Operation > Offshore Facilities and Subsea Systems > Mooring systems (0.63)
Simulation Research on Fatigue Crack Propagation Behavior in Bulb Stiffeners in Ship Structural Details
Yue, Jingxia (Wuhan University of Technology) | Xie, Hao (Wuhan University of Technology) | Dang, Zhifan (Wuhan University of Technology) | He, Zheng (Wuhan University) | Mao, Wengang (Chalmers University of Technology)
ABSTRACT Fatigue crack propagation behavior in bulb stiffeners, which are widely used in ship structures, is indispensable information for ship structures' fatigue life prediction. This paper aims to provide reasonable simulation process for the fatigue cracks propagated in bulb stiffeners based on the Finite Element Method (FEM) and extended Finite Element Method (XFEM) by using FRANC 3D and ABAQUS respectively. In order to evaluate the simulations, the shape of a three dimensional surface crack in full-scale bulb stiffener was measured and estimated through a full-scale fatigue test on a typical ship structure detail. According to the comparisons of the crack propagation path between the experiment and simulation results, the simulation results were verified to be reasonable and acceptable. Moreover, through analyzing the crack propagation behavior in bulb section, the fatigue failure criterion of bulb stiffeners was investigated. INTRODUCTION Fatigue failure is regarded as one of the most serious problems faced by marine structures during their service life. Bulb stiffeners are basic structural elements and widely used in ships and offshore platforms. Large amount of bulb stiffeners constitute the main frames of those engineering structures and help them to withstand complicated and harsh environmental loadings. Consequently, fatigue cracks tend to initiate at the structure details such as weld joints, cutouts, or connections of bulb stiffeners and other members. Therefore, the accurate information of fatigue crack propagation in the bulb section is important during the fatigue life prediction. Presently, classification societies (ABS, 2015; DNV, 2014; CCS, 2015) propose that if fatigue cracks propagated and penetrated through plate thickness, such structure members can be regarded as fatigue failure. As for the bulb stiffeners, the cracks initially propagate in the bulb, but the thickness of irregular bulbs is difficult to define. Then classification rules usually recommend an equivalent angle bar to substitute bulb stiffener in simplified fatigue assessment procedures.
- Well Completion > Hydraulic Fracturing (1.00)
- Facilities Design, Construction and Operation (0.69)
- Reservoir Description and Dynamics (0.66)
ABSTRACT Any catastrophic rupture scenarios of a steel pipe should be taken into considerations in the design and during the maintenance stage as the loss-of-containment may be accompanied by either property damage or fatal accidents. Ductile fracture of wrinkled (buckled) steel pipes on the tensile side of the cross-section is studied in this research as the most plausible case of ultimate failure for pressurized buried pipelines being subjected to monotonically increasing curvature. The results from two full-scale bending tests on X80 line pipe specimens that are pressurized up to 60% of specified minimum yield strength (SMYS) are considered as an input for the current study. The specimens possess the same dimensions and are made of X80 steel grade with different yield strength to tensile strength ratios (Y/T) of 90% and 83%. The specimen with higher Y/T ratio ruptured on the tensile side of the cross-section while experiencing post-buckling deformations. However, the specimen with lower Y/T ratio was unloaded after the formation of the local buckling. Finite element analysis (FEA) of the full-scale tests were conducted and verified using the experimental data. The power law is calibrated to model the post-necking plasticity of steel using material test data, and, cumulative fracture criterion in conjunction with general fracture strain locus for the pipelines' high-strength steel is implemented to predict the ductile fracture initiation in the pipe's wall. It is shown that the FE model accurately reproduces the load-displacement response and final rupture of the specimen with the higher Y/T ratio. For the other specimen, numerical simulation shows no rupture until the inner surface of the buckle comes into contact with itself which reveals that the lower Y/T ratio reduces the chance of rupture. Further numerical studies postulate that both Y/T ratio and internal pressure have a coupled effect on the rupture of wrinkled pipes and play a key role in triggering that kind of failure. That is, higher values of Y/T ratio and internal pressure increases the probability of the rupture of wrinkled pipes.
- North America > United States (1.00)
- North America > Canada > Alberta (0.49)
- Materials > Metals & Mining > Steel (1.00)
- Energy > Oil & Gas > Midstream (0.68)
- Well Completion > Hydraulic Fracturing (1.00)
- Data Science & Engineering Analytics (1.00)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Piping design and simulation (0.67)
- Reservoir Description and Dynamics > Reservoir Characterization > Faults and fracture characterization (0.49)
ABSTRACT This paper is devoted to micro-scale fracture testing of Arctic steel, by use of focused ion beam machined notched cantilevers. Bainite packets of a weld-simulated course grained heat-affected zone (CGHAZ) was the targeted microstructural aspect, with reference tests performed in pure iron. Micro-scale fracture testing has been developing in the last decade. The main objectives of micro-scale fracture tests are to obtain relevant toughness values for materials used at this scale, and to evaluate the fracture toughness of local microstructural aspects. The latter is the focus of this paper. Several models, including multiple barrier models, require specific material property inputs that are not obtainable through traditional testing at larger scale. Hence, micro-mechanical fracture has been applied to quantify these properties. Linear-elastic and elastic-plastic fracture mechanics parameters are presented and compared, with respect to testing material and temperature. Additionally, a new analytical tool is utilized to determine the criticality of a growing crack in terms of determining the energy required for further crack growth following initiation of stable crack growth. INTRODUCTION The industrial activity in the Arctic is rapidly increasing, where accidents may cause severe ecological ramifications. Rough climate conditions and temperatures as low as -60°C require materials with specialized mechanical properties. The materials must display sufficient fracture and wear resistance at low temperatures, while avoiding excessive maintenance and maintaining lifetime integrity. In order to overcome these challenges, small-scale fracture mechanisms and properties must be understood. BCC structures typically exhibit a rapid transition from ductile to brittle fracture, due to reduced mobility of screw dislocations and a reduced number of available slip systems, as the temperature is lowered (Brinckmann et al., 2008, Schreijäg et al., 2015). Full understanding of this transition requires a defined transition criterion. The change in fracture mode from ductile to brittle occurs over a temperature range that is closely interconnected with the change in deformation energy. Inside this temperature range, the metal exhibits fracture characteristics from both modes. There will be some ductile fracture near the notch, which changes to cleavage as the crack propagates. This is due to increased hydrostatic stresses as the propagation speed increases (Petch, 1958), implying that fracture will switch from ductile to brittle when the stress ahead of the fracture tip becomes capable of Griffith propagation. Fracture mechanics have gained increased interest due to several incidents where structures fail within the designed region of operation, initiating extensive research on fracture mechanisms, fracture initiation, propagation and arrest, as well as the temperature dependence of these mechanisms. In an attempt to enhance the understanding of the fracture mechanisms small-scale testing has been used to localize testing and to reduce the number of variables tested in each experiment.
- Europe > Norway (0.28)
- North America > United States (0.28)
- Well Completion > Hydraulic Fracturing (1.00)
- Well Drilling > Wellbore Design > Wellbore integrity (0.35)
- Reservoir Description and Dynamics > Reservoir Characterization > Faults and fracture characterization (0.34)
Fracture Mechanics-Based Approach for Quantifying Corrosion Damage of Offshore Structures
Ariffin, Mohammad Zaidi. (Nanyang Technological University (NTU), University of Southampton (UoS) ) | Xiao, Zhongmin. (Nanyang Technological University (NTU)) | Shenoi, R. Ajit. (University of Southampton (UoS))
ABSTRACT A fracture mechanics based approach is proposed to quantify the influence of corrosion damage on structural integrity. This approach investigates the corrosion surface for geometrical structural change consisting of a general thickness reduction combined with localised stress concentration where cracks are predicted to initiate or have already initiated from pitting. It comprises a numerical model of corroded SENT specimens of high strength offshore steel which is then validated against Thermoelastic Stress Analysis (TSA) and Digital Image Correlation (DIC) experimental results. With this validation, this concept can provide a basis for a complete test program using numerical method combined with in-situ inspection capabilities to estimate the remaining strength the corroded material. INTRODUCTION Offshore structures, pipelines and ships are exposed to the seawater environment which leads to corrosion damage. Furthermore, pitting causes high stress intensity regions that possibly develops into cracks (Turnbull, Wright et al. 2010). Since corrosion can lead to structural strength degradation and fatigue cracks, the integrity of such structures can be considerably affected (Wang, Wharton et al. 2014). As such, corrosion defects are commonly evaluated using the defect geometry and a plastic collapse-based criterion applying methods such as DNV-RP-F101 (Veritas 2010), while several codes exist to evaluate cracks including BS 7910 (Institution 2013). Recently, a hybrid defect known as Crack-in-Corrosion (CIC) (Bedairi, Cronin et al. 2012) has been identified and investigated to determine the integrity evaluation of corroded pipelines. If safety of these corroded marine platforms is to be ensured, taking into consideration such CIC defects and pitting with high stress concentration that may develops into cracks, a fracture mechanics based approach may have to be applied to evaluate the effects of corrosion on the strength of these structures (Zhang, Tan et al. 2015). By modelling the corrosion surface for geometrical structural change consisting of a general thickness reduction combined with an equivalent crack due to localised stress concentration of pitting, the influence of corrosion damage on structural integrity can be quantified using fracture mechanics parameters such as the Stress Intensity Factor, K, and the J-integral. Hence, this paper presents a numerical model of corrosion damage which is then checked against experimental results. With this model validated, a test program combined with inspection capabilities is proposed.
- Europe (0.28)
- North America > United States (0.28)
- Well Completion > Well Integrity > Subsurface corrosion (tubing, casing, completion equipment, conductor) (1.00)
- Well Completion > Hydraulic Fracturing (1.00)
- Production and Well Operations > Production Chemistry, Metallurgy and Biology > Corrosion inhibition and management (including H2S and CO2) (1.00)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Materials and corrosion (1.00)