Preventing Girth Weld Failure in Pipelines: Measurement of Loads and Application of Assessment Methods

2020 ◽  
Author(s):  
Andy Young ◽  
Robert M. Andrews
Keyword(s):  
Transmission Lines ◽  
Oil And Gas ◽  
Large Diameter ◽  
Ground Movement ◽  
External Loading ◽  
Key Factors ◽  
Axial Loads ◽  
Contributing Factors ◽  
Increased Risk ◽  
Girth Welds

Abstract Pipeline failures from circumferential cracking at girth welds continues to affect large diameter oil and gas transmission lines, even for modern lines constructed this century. The key factors that contribute to the failure at girth welds are the dimensions of defects present, the material properties of the pipe and weldments, and the presence of loading that drives crack growth. The mechanisms of failure are well understood, but identifying and measuring the contributing factors can be a challenge. Locating girth welds that are subject to elevated loads will enable operators to focus on sections with an increased threat of failure. In this paper, we consider each of the key factors, how these are identified and defined, and the uncertainties in the measurement process. Specific attention is applied to the presence and quantification of loads and how these influence the potential for failure. This includes sources of active external loading due to ground movement, for example, or loads generated in the pipeline from the construction process. Loads can also be quantified by measuring bending strain from inline inspection inertial measurement units. A more complete picture of pipeline loading can be established by integrating a structural analysis that accounts for the direction of pipeline movement and the presence of axial loads. The relationship between assessing pipeline integrity from ground movement — typically with strainbased methods — and establishing whether the defect can survive the load is explored. The relative contribution of bending and axial loads in the failure of defects is considered. The outcome of the study will assist pipeline operators in prioritising actions that enable the quantification of the all the key parameters. The resultant analysis will provide guidance on the girth welds that have an increased risk of failure and this will enable protective actions to be defined and scheduled accordingly.

Buckling Resistance of Large Diameter Spiral Welded Linepipe

2004 ◽  
Author(s):  
Tom Zimmerman ◽  
Chris Timms ◽  
Jueren Xie ◽  
James Asante
Keyword(s):  
Oil And Gas ◽  
Weld Seam ◽  
Large Diameter ◽  
Ground Movement ◽  
Finite Element Analyses ◽  
Line Pipe ◽  
Diameter Pipe ◽  
Buckling Resistance ◽  
Analytical Research ◽  
Full Scale Tests

This paper contains the results of an experimental and analytical research program to determine the compressive buckling resistance of large-diameter, spiral-welded linepipe. Buckling resistance is important for pipe intended for service in Arctic, oil and gas pipeline systems, where pipes may be subjected to high bending strains caused by various ground movement events. The experimental work consisted of four full-scale tests of 30-inch (762 mm) diameter pipe subjected to various combinations of internal pressure, axial force and bending. The pipe specimens were fabricated using two material grades (X70 and X80) and two D/t ratios (82 and 48). Finite element analyses of the four tests were conducted to develop a better understanding of specimen behavior. The results suggest that spiral welded linepipe is as good as longitudinally welded line pipe in terms of buckling capacity. The spiral weld seam was in no way detrimental to the pipe performance.

Ranking and Sensitivity Analysis of Key Factors for Successful Project Management Performance: An Application of AHP for Oil and Gas Sector

2018 ◽  
Vol 6 (2) ◽  
Author(s):  
Farhaj Ishtiaq ◽  
Mirza Jahanzaib
Keyword(s):  
Sensitivity Analysis ◽  
Project Management ◽  
Analytical Hierarchy Process ◽  
Oil And Gas ◽  
Planning Process ◽  
Project Planning ◽  
Key Factors ◽  
Management Performance ◽  
Hierarchy Process ◽  
Oil And Gas Sector

<p>Complexities faced by oil and gas projects due to uncertainty and risk, demand the implementation of project management techniques for their successful completion. Therefore, this is made by using analytical hierarchy process, to identify and prioritize the key factors for successful project management performance of oil and gas projects. These factors are categorized into three groups which include attributes of project staff, project planning process and assessment of project quality. Using expert choice, a hierarchy is developed followed by pairwise comparison based upon data collection from industrial experts of oil and gas sector. Results of analytical hierarchy process (AHP) concluded that, project completion within estimated time and budget, clarity of objectives and involvement of top management are most crucial elements for improvement in project management performance of oil and gas projects. Whereas sensitivity analysis being carried out according to three different scenarios highlighted factors according to their relative importance.</p>

Integrity Management of Ground Movement Hazards

2016 ◽  
Author(s):  
Yong-Yi Wang ◽  
Don West ◽  
Douglas Dewar ◽  
Alex McKenzie-Johnson ◽  
Millan Sen
Keyword(s):  
Management Program ◽  
Ground Movement ◽  
Tensile Failure ◽  
Weld Strength ◽  
Factors Affecting ◽  
Ground Movements ◽  
Decision Points ◽  
Starting Point ◽  
Integrity Management ◽  
Girth Welds

Ground movements, such as landslides and subsidence/settlement, can pose serious threats to pipeline integrity. The consequence of these incidents can be severe. In the absence of systematic integrity management, preventing and predicting incidents related to ground movements can be difficult. A ground movement management program can reduce the potential of those incidents. Some basic concepts and terms relevant to the management of ground movement hazards are introduced first. A ground movement management program may involve a long segment of a pipeline that may have a threat of failure in unknown locations. Identifying such locations and understanding the potential magnitude of the ground movement is often the starting point of a management program. In other cases, management activities may start after an event is known to have occurred. A sample response process is shown to illustrate key considerations and decision points after the evidence of an event is discovered. Such a process can involve fitness-for-service (FFS) assessment when appropriate information is available. The framework and key elements of FFS assessment are explained, including safety factors on strain capacity. The use of FFS assessment is illustrated through the assessment of tensile failure mode. Assessment models are introduced, including key factors affecting the outcome of an assessment. The unique features of girth welds in vintage pipelines are highlighted because the management of such pipelines is a high priority in North America and perhaps in other parts of the worlds. Common practice and appropriate considerations in a pipeline replacement program in areas of potential ground movement are highlighted. It is advisable to replace pipes with pipes of similar strength and stiffness so the strains can be distributed as broadly as possible. The chemical composition of pipe steels and the mechanical properties of the pipes should be such that the possibility of HAZ softening and weld strength undermatching is minimized. In addition, the benefits and cost of using the workmanship flaw acceptance criteria of API 1104 or equivalent standards in making repair and cutout decisions of vintage pipelines should be evaluated against the possible use of FFS assessment procedures. FFS assessment provides a quantifiable performance target which is not available through the workmanship criteria. However, necessary inputs to perform FFS assessment may not be readily available. Ongoing work intended to address some of the gaps is briefly described.

Identifying Key Safety Culture Factors for the Offshore Industry

2021 ◽  
Author(s):  
Ning Lou ◽  
Ezra Wari ◽  
James Curry ◽  
Kevin McSweeney ◽  
Rick Curtis ◽  
...  
Keyword(s):  
Safety Culture ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Transportation Safety ◽  
Key Factors ◽  
Gas Industry ◽  
The Us ◽  
Offshore Industry ◽  
Offshore Oil And Gas ◽  
Offshore Oil

This research identifies key factors, or safety culture categories, that can be used to help describe the safety culture for the offshore oil and gas industry and develop a comprehensive offshore safety culture assessment toolkit for use by the US Gulf of Mexico (GoM) owners and operators. Detailed questionnaires from selected safety culture frameworks of different industries were collected and analyzed to identify important safety culture factors and key questions for assessment. Safety frameworks from different associations were investigated, including the Center for Offshore Safety (COS), Bureau of Safety and Environmental Enforcement (BSEE), and the National Transportation Safety Board (NTSB). The safety culture factors of each of these frameworks were generalized and analyzed. The frequency of the safety culture factors in each framework was analyzed to explore commonality. The literature review and analysis identified a list of common factors among safety culture frameworks.

Extending FMC Based Ultrasonic Imaging Practices to Smaller Wall Thickness

2021 ◽  
Author(s):  
Niels Pörtzgen ◽  
Ola Bachke Solem
Keyword(s):  
Carbon Steel ◽  
Wall Thickness ◽  
Oil And Gas ◽  
Ultrasonic Inspection ◽  
Ultrasonic Imaging ◽  
Advanced Technology ◽  
Front Wall ◽  
Thin Wall ◽  
Destructive Testing ◽  
Girth Welds

Abstract During the construction of pipelines for the transportation of oil and gas, the inspection of girth welds is a critical step to ensure the integrity and thereby the safety and durability of the pipeline. In this paper we present an advanced technology ‘IWEX’ for the non-destructive testing of welds based on 2D and 3D ultrasonic imaging. This technology allows for safe, fast, and accurate inspection whereby the results are presented comprehensively. This will be illustrated with results from a recent project. The IWEX technology is based on an ultrasonic inspection concept, whereby ‘fingerprints’ of ultrasonic signals are recorded, also referred to as ‘full matrix capture’ (FMC) data. Then, an image area is defined, consisting out of pixels over an area large enough to cover the inspection volume. With the FMC data, image amplitudes are calculated for each pixel so that the shape of geometry (back wall, front wall, cap, and root) and possible indications are revealed. As opposed to traditional ultrasonic testing strategies, the detection and sizing of indications is therefore less dependent on its orientation. The project concerned the inspection of J and V welds from a 5.56″ diameter carbon steel pipe with an 8.4mm wall thickness. The wall thickness is relatively thin compared to common inspection scopes. Therefore, the inspection set-up was adapted, and procedural changes were proposed. Consequently, additional validation efforts were required to demonstrate compliance with the required inspection standard; DNVGL-ST-F101: 2017. As part of this, welds were scanned with seeded indications and the reported locations were marked for macro slicing under witnessing of an independent representative from DNVGL. The resulting images from the indications in the welds showed great detail with respect to the position, orientation and height of the indications. A quantitative comparison with the results from the macro slices was performed, including a statistical analysis of the height sizing and depth positioning accuracies. From the analysis, it could be observed that the expected improvements with respect to the resolution and sizing accuracy were indeed achieved. Thereby, the procedure has proven to be adequate for the inspection of carbon steel girth welds within the thin wall thickness range (~6mm to ~15mm). The IWEX technology is a member of the upcoming inspection strategy based on imaging of ultrasonic FMC data. This strategy can be considered as the next step in the evolution of inspection strategies after phased array inspection. The IWEX technology has been witnessed and qualified by independent 3rd parties like DNVGL, this makes the IWEX technology unique in its kind and it opens opportunities for further acceptance in the industry and other inspection applications.

Access and Logistics Challenges in Mountain Terrain Pipeline Projects

2014 ◽  
Author(s):  
Mark McDougall ◽  
Ken Williamson
Keyword(s):  
Construction Projects ◽  
Large Scale ◽  
Oil And Gas ◽  
Large Diameter ◽  
Gas Production ◽  
Additional Time ◽  
Oil And Gas Production ◽  
Road Design ◽  
Regulatory Constraints ◽  
The Right

Oil and gas production in Canada’s west has led to the need for a significant increase in pipeline capacity to reach export markets. Current proposals from major oil and gas transportation companies include numerous large diameter pipelines across the Rocky Mountains to port locations on the coast of British Columbia (BC), Canada. The large scale of these projects and the rugged terrain they cross lead to numerous challenges not typically faced with conventional cross-country pipelines across the plains. The logistics and access challenges faced by these mountain pipeline projects require significant pre-planning and assessment, to determine the timing, cost, regulatory and environmental impacts. The logistics of pipeline construction projects mainly encompasses the transportation of pipe and pipeline materials, construction equipment and supplies, and personnel from point of manufacture or point of supply to the right-of-way (ROW) or construction area. These logistics movement revolve around the available types of access routes and seasonal constraints. Pipeline contractors and logistics companies have vast experience in moving this type of large equipment, however regulatory constraints and environmental restrictions in some locations will lead to significant pre-planning, permitting and additional time and cost for material movement. In addition, seasonal constraints limit available transportation windows. The types of access vary greatly in mountain pipeline projects. In BC, the majority of off-highway roads and bridges were originally constructed for the forestry industry, which transports logs downhill whereas the pipeline industry transports large equipment and pipeline materials in both directions and specifically hauls pipe uphill. The capacity, current state and location of these off-highway roads must be assessed very early in the process to determine viability and/or potential options for construction access. Regulatory requirements, environmental restrictions, season of use restrictions and road design must all be considered when examining the use of or upgrade of existing access roads and bridges. These same restrictions are even more critical to the construction of new access roads and bridges. The logistics and access challenges facing the construction of large diameter mountain pipelines in Western Canada can be managed with proper and timely planning. The cost of the logistics and access required for construction of these proposed pipeline projects will typically be greater than for traditional pipelines, but the key constraint is the considerable time requirement to construct the required new access and pre-position the appropriate material to meet the construction schedule. The entire project team, including design engineers, construction and logistics planners, and material suppliers must be involved in the planning stages to ensure a cohesive strategy and schedule. This paper will present the typical challenges faced in access and logistics for large diameter mountain pipelines, and a process for developing a comprehensive plan for their execution.

scholarly journals Systemic Capillary Leak Syndrome (Clarkson Syndrome) in Cancer Patients: A Systematic Review

2018 ◽  
Vol 7 (11) ◽  
pp. 418 ◽  
Author(s):  
Jae Shin ◽  
Keum Lee ◽  
I. Lee ◽  
Ji Oh ◽  
Dong Kim ◽  
...  
Keyword(s):  
Cancer Patients ◽  
Case Reports ◽  
Laboratory Data ◽  
Capillary Leak Syndrome ◽  
Treatment Modalities ◽  
Capillary Leak ◽  
Contributing Factors ◽  
Systemic Capillary Leak Syndrome ◽  
Increased Risk ◽  
Anti Cancer

Systemic capillary leak syndrome (SCLS) is a rare disease characterized by shock caused by capillary hyperpermeability. The disease can occur in cancer patients and effective therapeutic strategies have not been established yet. The aim of the study was to analyze the clinical and laboratory data, treatment modalities, and mortality rate of patients and to identify contributing factors leading to mortality of SCLS in cancer. We searched MEDLINE (inception to July 2018) and of 4612 articles, we identified 62 case reports on SCLS associated with cancer or cancer-related drugs in a total of 53 articles. SCLS was associated with cancer itself in 43.6%, with anti-cancer agents in 51.6% and bone marrow transplantation (BMT) in 4.8%. Among anti-cancer agents, granulocyte-colony stimulating factor (G-CSF) was the most frequently associated drug (14.6%), followed by interleukin (IL)-2 (11.4%). The most common associated malignancies were hematologic (61.3%) with non-Hodgkin lymphoma (22.7%) and multiple myeloma (12.9%) being the leading causes. Common symptoms and signs included dyspnea (27.4%), edema (67.7%), hypotension (32.2%), pleural effusion (29.0%), ascites (22.7%), oliguria (22.7%), and weight gain (21.0%). Patients with SCLS were treated with steroids (59.7%), volume replacement (33.8%), diuretics (24.2%), inotropes (9.6%), methylxanthines (12.8%), β2 agonists (4.8%), while intravenous immunoglobulins (IVIG) were administered in 2 patients (3.2%) only. Among sixteen deaths during follow-up, four were directly attributed to SCLS. Hematologic malignancies were associated with an increased risk for mortality (hazard ratio (HR) 8.820, 95% confidence interval (CI) 1.126–69.063, p = 0.038). Taken together, SCLS can be one important adverse event in cancer patients and careful monitoring of fluid volume is required in the management of SCLS.

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