bluuebunny/crossref_metadata_2025 huggingface dataset:
Inline Inspection for Cracks in Gas Pipelines: Enhancements Derived From 5 Years’ Operational Experience
Authors: Tappert Stephan , Allen David Lee , Mann Andy , Balzer Matthias , Van Boven Greg
Published: July 2009

This paper will summarize the evolution of the EMAT technology since GE’s initial product launch in 2002. A key focus of this paper will be outlining several tool and analysis enhancements that result from the evaluation of over a 1000kms of EMAT tool pipeline inspection and 207 field confirmations. These tool and analysis enhancements are now incorporated in GE’s new 30 inch third generation EMAT In-Line Inspection (ILI) tool.
Burst Tests on Pipeline Containing Irregular Shaped Corrosion Defects
Authors: Benjamin Adilson C. , Franzoi Aldo R. , Freire Jose´ Luiz F. , Vieira Ronaldo D. , Diniz Jorge L. C.
Published: July 2009

A corrosion defect can be considered as being of a regular shape if its defect depth profile is relatively smooth and the longitudinal area of metal loss is approximately rectangular. A corrosion defect can be considered as being of an irregular shape if its defect depth profile presents one or more major peaks in depth. In this paper the burst tests of four tubular specimens are presented. In these tests the tubular specimens were loaded with internal pressure only. The specimens were cut from longitudinal welded tubes made of API 5L X80 steel with a nominal outside diameter of 457.2 mm (18 in) and a nominal wall thickness of 7.93 mm (0.312 in). Each of the four specimens had one external irregular shaped corrosion defect, machined using spark erosion. Measurements were carried out in order to determine the actual dimensions of each tubular specimen and its respective defect. Tensile specimens and impact test specimens were tested to determine material properties. The failure pressures measured in the laboratory tests are compared with those predicted by six assessments methods, namely: the ASME B31G method, the RSTRENG 085dL method, the DNV RP-F101 method for single defects, the RPA method, the RSTRENG Effective Area method and the DNV RP-F101 method for complex shaped defects.
An Integrated Outflow-Spill Modeling Approach for Risk-Based Valve Placement of Liquid Transmission Pipelines
Authors: Deng Chuntao , Zuczek Patricia , Adams Keith , Mihell Jim
Published: July 2009

Weir et al’s work [1] applied the relative effectiveness of outflow reduction to address the Intelligent Block Valve Placement (IVP) for liquid transmission pipelines. In their work, the effectiveness measure for each potential valve placement location is a length-weighted sum of the calculated volume reduction at all points along the pipeline in which the outflow volumes are multiplied by weighting factors that reflect the relative importance of spills in different sensitive areas; In our work, the original approach was enhanced to more quantitatively reflect both the likelihood of line failure and the full consequences of line failure as impacted by additional valve placement considering both block and check valves. This paper presents an IVP approach integrated with a quantitative risk assessment through which block and/or check valve placement schemes are optimized. The process involves a computer analysis in which block and check valves are iteratively selected and placed for each case. The risk reduction associated with each case is determined as the product of failure likelihood and the weighted average cost reduction. Failure likelihood is typically quantified using reliability methods or industry failure statistics, and is not the focus of this paper. The cost reduction focuses on environmental factors, which are represented by the clean-up cost of a spill that impacts both sensitive and non-sensitive areas for each incidence. In modeling consequence, the reduction of outflow potential is quantified by an in-house outflow simulation tool; and the potential spill impact is assessed through a mechanistic in-house VBA extension of ArcGIS, a three-dimensional (3-D) overland-hydrographical spill simulation package. Optimal valve placement design is achieved by balancing the costs associated with environmental risk with the costs associated with installing and maintaining block and check valves. The valves included in the assessment for outflow simulation and cost analysis are check valves and block valves. The automatic valve placement simulation is terminated when the valve installation/maintenance cost outweighs the benefits of placing more valves in the line.
BioMonitoring: A Key to Successful Environmental Compliance for Pipeline Construction—Cypress Pipeline Project: A Case Study
Authors: Goldstein Jason M. , Goldstein Rebecca F.
Published: July 2009

Southern Natural Gas Company (Southern), an El Paso Company, used BioMonitors to ensure full environmental compliance with the regulatory conditions associated with the construction of the Cypress Pipeline Project. The 167-mile Cypress Pipeline originates near Savannah, Georgia, and terminates west of Jacksonville, Florida. In preparation for construction of this project, Southern engaged in extensive consultation and negotiation with numerous federal, state, and local regulatory agencies. It became apparent during the consultation process that Southern would need a highly skilled biologist on-site during construction to fulfill the onerous conditions required by these agencies. Furthermore, specific state water quality permit conditions contained frequent sampling and reporting requirements that required specially-certified personnel. For these reasons, Southern used two BioMonitors (qualified on-site biologists with construction expertise) during construction who were dedicated to uphold the specialized environmental compliance program for the project. Herein, we illustrate this creative method for successfully negotiating contentious environmental issues and fully complying with the specialized environmental compliance conditions that frequently stem from sensitive agency consultation and intricate permit stipulations.
Cathodic Protection Monitoring: A New Task for ILI Tools
Authors: Scott Paul K.
Published: July 2009

Identifying deficiencies and monitoring the effectiveness of a pipeline’s cathodic protection (CP) system can be difficult, expensive and time consuming — especially when the pipe is located in an area of difficult access. Now that CP may be monitored via in-line inspection tools (smart pigs), the status of CP systems can be confirmed and problems identified regardless of the location, accessibility, or condition of the pipeline right of way. An in-line inspection tool capable of reading and recording the magnitude and polarity of current supplied by cathodic protection has been developed and tested in a variety of pipelines. The results show that CP currents can be quickly, accurately and efficiently measured without access to the outside surface of the pipe. For difficult-to-access areas, the CPCM™ In-Line Cathodic Protection Inspection Tool provides for a reliable, cost-effective, and time-saving way to monitor, validate, or trouble shoot a pipeline’s cathodic protection system. This paper will present results from field trials as well as the first commercial deployments of the technology. A discussion of how cathodic protection and pipeline features are identified will be included. This tool is the result of the joint development effort of Shell Pipeline Co. LP, Shell Global Solutions, Baker Hughes PMG and the US DOT.
Determination of Mechanical Properties of High Strength Linepipe
Authors: Klein Randy , Collins Laurie , Hamad Fathi , Chen Xiande , Bai Dengqi
Published: July 2009

Commercial scale trials of X100 for Artic gas transmission pipelines have been conducted at IPSCO. Different alloying systems and thermo-mechanical controlled processes have been employed to make X100 coils. The coils were made into spirally welded pipes at IPSCO Spiral Mill in Regina, Canada. These pipes were tested in different conditions, namely as-welded, after hydro-testing, and after thermal coating. Therefore, the effects of as-supplied material and pipe-making processes on the final mechanical properties of pipe were evaluated. It was found that the tensile specimen size and sampling location had a noticeable effect on the testing results. The difference was also observed between the flattened strap specimen and round bar. The influence of the anisotropy of the as-supplied coils and the thermal coating on the final pipe properties will also be presented.
Some Strategies for Effective Cultural Resources Management in Pipeline Permitting
Authors: Bergman Christopher A. , Law Steven , Haag Crista , Hein John , Brice Donald
Published: July 2009

The inventory, evaluation and treatment of cultural resources represent a significant challenge for siting and permitting natural gas pipelines. Project sponsors assist the Federal Energy Regulatory Commission’s Office of Energy Projects with meeting its obligations under Section 106 of the National Historic Preservation Act. The increasing sophistication of compliance with Section 106 is reflected in the Office of Energy Project’s 2002 Guidelines for Reporting on Cultural Resources Investigations for Pipeline Projects. Recent pipeline projects in the United States have involved environmental study corridors that are both wide and extensive, a combination that results in the identification of large numbers of cultural properties. The process of cultural resources management begins in the project planning stage with the development of site location modeling, analysis of previous investigations within or near Areas of Potential Effect, and consideration of the likelihood for encountering potentially eligible National Register of Historic Places properties. Using this information, site detection survey strategies can be developed that intensively target only sensitive portions of the Area of Potential Effect. During the survey, identification of archaeological sites, historic structures, or cultural landscapes requires prompt evaluation of National Register eligibility status for the purposes of avoidance or development of treatment plans. This presentation considers the Section 106 compliance process and how project sponsors can effectively manage cultural resources to ensure cost effectiveness and maintenance of restricted project schedules, while meeting the objectives of the National Historic Preservation Act.
Roads, Pads, and Access Along Gravel Free Pipeline Routes
Authors: Tart Rupert G.
Published: July 2009

In many of the major oil and gas fields in the North American Arctic, gravel is abundant and close to the production fields and the pipeline routes. In many other Arctic areas in Europe and Asia, gravel is almost non-existent. As new fields are being developed, gravel free areas are being encountered in more areas such as the National Petroleum Reserve Alaska (NPRA) and many of the Russian oil fields west and east of the Ural Mountains and into the Yamal Peninsula. Without free draining gravel, access and development of these new fields becomes more costly, more schedule sensitive, and more complicated. This paper looks at options for roads, pads, and access for developing the oil fields and building and operating the pipelines in areas where gravel deposits are sparse. Some of the options that are discussed and evaluated are using: 1. Additives to increase the strength of available fine-grained materials. 2. Ice and snow pads and roads. 3. Seasonal scheduling of construction. 4. Various road and pad surfacing options including: a) Year-around ice pads, b) Concrete pads and pavements, and c) Mats constructed of various materials. 5. Dredging and draining to obtain available sandy materials from waterways. 6. Geofabrics to contain ice rich materials placed in winter. 7. Methods for maintaining the thermal state of winter placed embankment.
New Frontienrs in Pipeline Pressure Isolation: Non-Invasive, Without De-Pressurizing, Production Loss or Flow Interruption
Authors: Selden Rush , Sim Mark
Published: July 2009

There are several methods for pressure isolating pipelines. Along with hot tapping and stopple and freeze plugging, there is another common method known as remote controlled (tether-less) pipeline plugging, whose use is increasing — both offshore and onshore. This paper will review piggable tether-less plugging technology, provided by TDW Offshore Services using the SmartPlug™, and case histories whereby a bi-directionally piggable, remotely actuated (tether-less) plug is deployed to allow pipeline operators to perform repair work, modifications, or tie-ins on pipeline systems without interrupting production in the remaining part of the pipeline system, i.e., while operating live and at production pressure. Specifically this paper will address two new technologies: First, allowing high pressure isolation of thin wall pipe, and second, of spiral wound pipe, both without welding, tapping or leaving any trace of the fact that an isolation occurred. Some advantages of tether-less plugging technology are: • Plugging tools have higher pressure containment capacity than other plugging methods, typically up to 3,000 psi. • Bi-directionally piggable, able to negotiate as small as 1.5D bends, operated and monitored entirely via remote control (tether-less through-wall control and communication system). • Compared to hot tapping, welding a fitting on the pipeline is not required, and no need to hot tap (drill) into the pipeline, no future leak path and no issues regarding cuttings or coupon. This latest frontier of pressure isolation allows for plugging tools that are fail-safe (the higher the differential pressure the harder they set) with zero leakage tolerance. They can be configured for job specific requirements such as double or single block, and can allow for hydrotesting the completed work. The most important advantage is that they eliminate the time needed and lost production cost of displacing pipeline product, flaring, depressurizing, emptying the line, and re-commissioning the line. In addition, specifically this paper will address the latest technology advances allowing high pressure isolation of thin wall (8mm/0.32 inch) spiral wound pipe using external pressure reinforcement clamps over the pressure isolation tool during an onshore project on a 24″ methane gas pipeline. During the isolation, a portion of the upstream pipeline was removed and replaced while the entire pipeline downstream of the pressure isolation remained under full operating pressure, thus requiring no loss of production from downstream assets during the repair. Once complete the tools were released and pigged from the line, leaving no holes, no welds, no future leak path and no trace that any event occurred on the pipeline in that location.
Designing Offshore Pipeline Safety Systems Utilising Flow and Pressure in Multi Design Pressure Pipeline Systems
Authors: Hausken Gjertrud Elisabeth , Stokke Jo̸rn-Yngve , Berland Steinar
Published: July 2009

The Norwegian Continental Shelf (NCS) has been a main arena for development of subsea pipeline technology over the last 25 years. The pipeline infrastructure in the North Sea is well developed and new field developments are often tied in to existing pipeline systems, /3/. Codes traditionally require a pipeline system to be designed with a uniform design pressure. However, due to the pressure drop when transporting gas in a very long pipeline, it is possible to operate multi design pressure systems. The pipeline integrity is ensured by limiting the inventory and local maximum allowable pressure in the pipeline using inlet and outlet pressure measurements in a Safety Instrumented System (SIS). Any blockage in the pipeline could represent a demand on the safety system. This concept was planned to be used in the new Gjo̸a development when connecting the 130 km long rich gas pipeline to the existing 450 km long FLAGS pipeline system. However, a risk assessment detected a new risk parameter; the formation of a hydrate and subsequent blockage of the pipeline. In theory, the hydrate could form in any part of the pipeline. Therefore, the pipeline outlet pressure could not be used in a Safety Instrumented System to control pipeline inventory. The export pressure at Gjo̸a would therefore be limited to FLAGS pipeline code. Available pressure drop over the Gjo̸a pipeline was hence limited and a large diameter was necessary. Various alternatives were investigated; using signals from neighbour installations, subsea remote operated valves, subsea pressure sensors and even a riser platform. These solutions gave high risk, reduced availability, high operating and/or capital expenses. A new idea of introducing flow measurement in the SIS was proposed. Hydraulic simulations showed that when the parameters of flow, temperature and pressure, all located at the offshore installation, were used; a downstream blockage could be detected early. This enabled the topside export pressure to be increased, and thereby reduced the pipeline diameter required. Flow measurement in Safety Instrumented Systems has not been used previously on the NCS. This paper describes the principles of designing a pipeline safety system including flow measurement with focus on the hydraulic simulations and designing the safety system. Emphasis will be put on improvements in transportation efficiency, cost reductions and operational issues.
Hybrid Laser/Gas Metal Arc Welding of High Strength Steel Gas Transmission Pipelines
Authors: Harris Ian D. , Norfolk Mark I.
Published: July 2009

Despite significant investment, one-shot welding and power beam processes have not been very successful in achieving real benefits in pipeline construction. The most promising of the newer and more innovative welding processes is the hybrid Laser/arc welding process (HLAW), which can complete 5G welds, assure weld soundness, material properties, and an acceptable geometric profile. The combination of new lasers and pulsed gas metal arc welding (GMAW-P) power source technologies have led to important innovations in the HLAW process that have been shown to increase the travel speed for successful root pass welding. In particular, high power Yb fiber lasers with high efficiency (25% compared with 3% for a Nd:YAG laser) allow a 10kW laser to be built the size of a refrigerator. This allows for previously unheard of portability and power levels for use outside the laboratory and on the pipeline right-of-way. The objective was to develop and apply an innovative HLAW system for mechanized welding of high strength, high integrity, pipelines and develop 5G welding procedures for X80 and X100 pipe, including mechanical testing to API 1104. The main goal of a cost-matched JIP was to develop a prototype hybrid high power Yb fiber laser and GMAW head based on a commercially available bug and band system (Figure 1). Under the DOT project, the subject of this paper, innovative technologies for pipeline girth welding were developed. External hybrid root pass welding techniques were developed for variations of laser power (4–10 kW) and root face thickness (4–8 mm) as this has the greatest potential to meet existing pipeline integrity requirements and facilitate the use of new high power Yb fiber lasers for high speed HLAW of pipe root passes. Following the integration of the Yb fiber laser and GMAW head onto a commercially available bug and band system (CRC-Evans P450) the system was used to achieve full penetration welds with a 4 mm root at a travel speed of 2.3 m/min. The root welds were made in a “double down” configuration using laser powers up to 10kW and travel speeds up to 3 m/min. The final objective of the project is to demonstrate the hybrid LBW/GMAW system under field conditions.
The Development of an Emergency Repair System, and a Case Study for a Remote Gas Pipeline
Authors: Palmer-Jones Roland , Hume John , Linkleter Nadia , Minhas Vishal , Christie Duncan
Published: July 2009

Large diameter long distance gas pipelines are high value assets which have to be kept operating. When damage occurs, or the pipeline fails, a rapid repair is critical to allow full operation to re-start. Suitable equipment and skilled personnel are required to ensure a repair can be completed for the range of damage that can occur. Many locations around the world can be remote or hostile creating an absence of both available skills (such as welders) and equipment for emergency repairs. Consequently, some operators need comprehensive repair systems and skills that can be mobilised quickly and easily. This paper presents an overview of the options for the emergency repair of different types of pipeline damage, and provides a strategy, and a case study of the process used to define the equipment and support contracts needed by the operator of a gas pipeline in a remote area to ensure that they could complete a repair to any credible damage or failure within just 7 days.
Micro-Electrochemical Characterization of the Synergism of Hydrogen and Stress in Anodic Dissolution of Steel and Its Implication on Pipeline Stress Corrosion Cracking
Authors: Cheng Y. Frank , Tang X.
Published: July 2009

Localized electrochemical impedance spectroscopy (LEIS) technique was used to investigate the effects of stress and hydrogen as well as their synergism on anodic dissolution of steel under near-neutral pH condition where pipeline stress corrosion cracking (SCC) has been reported. There exists a threshold stress value, under which there is little effect of applied stress on anodic dissolution of steel. Above the value, the dissolution rate of steel increases with the stress. Hydrogen-charging enhances anodic dissolution of steel, which is attributed to the effect of hydrogen on the formation of corrosion product layer and the activation of the steel. The stress effect factor and the stress-hydrogen synergism effect factor are quantified. A detailed analysis shows that the synergism of stress and hydrogen at crack tip is expected to play an important role in near-neutral pH SCC of pipelines.
Direct Strain Calculation of Pipe Line Dent From Knot Migration Using a Kinematic Model Free of Material Properties
Authors: Belanger Adrian A. , Narayanan Ram
Published: July 2009

With advances in interpolation and noise filtering, a pure strain calculation can be derived using the fundamental definition of the strain tensor and a shell model with only a few assumptions. Deformation data acquired on the inner surface of the pipe is used to calculate the positional knots that define the inner shell surface from which the displacement vectors of the median plane can be calculated. Using a shell model around the median plane, the strains can be calculated on the inner and outer surfaces based purely on the displacement of the knot positions. To validate this procedure, an FEM is built using a nonlinear stress-strain response for the steel to model its elasto-plastic behavior with associated kinematic hardening behavior. The model uses a second order shell element with plasticity, large deformation, and large strain capabilities.
The Use of Visualization Techniques to Plan, Design, and Permit Pipeline Projects
Authors: Rowe Stephen T. , Zielinski Kim M.
Published: July 2009

Because pipeline routing, design, and permitting is complex and often controversial, it is advantageous to utilize new technologies to expedite the overall process. Potential pipeline routes can be modeled in a Geographic Information System (GIS) to facilitate early identification of engineering and environmental constraints. This allows time for preliminary engineering and permitting, avoiding time-consuming and costly re-routing later on. Why take the planning, design, and permitting into a virtual world? A primary advantage of a virtual GIS model is based on the way humans process information. It is estimated that 50% of the brain’s neurons are involved in vision. Two-dimensional (2D) and three-dimensional (3D) visualizations simulate spatial reality, thus allowing the viewer to quickly recognize and understand complex concepts such as changes in elevation or tree growth over time. This is especially true of 3D displays, which involve a larger portion of the brain in the problem solving process (Swanson, 2002). Using spatial visualizations—or geo-visualizations—engineers, planners, and environmental scientists involved in pipeline permitting can quickly and easily identify engineering and environmental constraints along a route and may be more effective in conveying their plan to stakeholders. Many pipeline routes are inaccessible due to either rough terrain or restricted access. Virtual routes can be evaluated by the design team without each team member travelling to the project location, saving valuable project time and reducing project budget. Once a GIS model for the entire route is created, 2D and 3D illustrations allow a project proponent to “sell” a particular alternative or project mitigation to permitting agencies and stakeholders, and potentially accelerate the overall permitting process.
Technology Transfer: Moving Knowledge From Research Into Industry Standards
Authors: Johnson Cliff , Smith Robert W.
Published: July 2009

Recently the Pipeline & Hazardous Materials Safety Administration (PHMSA) of the US Department of Transportation signed a Memorandum of Agreement (MOA) with the Pipeline Standards Developing Organizations Coordinating Council (PSDOCC). This MOA is intended to enhance the cooperation and coordination between the Parties to facilitate a more effective and efficient integration of pipeline safety research and development (R&D) results into the development and revision of voluntary consensus technical standards. This effort is the first of its kind in the US for the pipeline industry. This presentation will provide background about the PSDOCC and its role in the development of standards and its role of technology transfer for the pipeline industry — moving knowledge from R&D into industry standards and education into possible regulations.
Flow Performance Investigation of Rich Gas Pipelines
Authors: Deng Daoming , Gong Jing
Published: July 2009

For the rich gas transfer schemes, extraction of NGL from the natural gas is not required in the oil field or gas condensate field, so the gas treatment processes in the field is simplified and the expense from the storage and transportation of NGL is saved, and the gas processing plant could be located far from the field. Rich gas can be pipelined in single phase and/or in two-phase mode. Compared with the gas-condensate ones, the rich gas pipelines behave with lower liquid loading, and are easily controlled operationally. Therefore, the rich gas pipelining modes are increasingly preferred especially in offshore and desert petroleum developments. Prediction of the performances of rich gas flow in pipelines covers a series of calculations for fluid phase behavior, fluid properties, pressure gradient, liquid holdup and temperature drop. In the paper, a hydraulic and thermodynamic model for the analysis of rich gas flow in pipelines with single-phase or two-phase modes is outlined. On account of the low liquid holdup of rich gas two-phase flow in pipelines, the constitutive relation resulting from Ottens et al (2001) correlation is selected. The iterative method to compute the pressure gradient, liquid holdup, and temperature drop of a pipe increment is developed, which shows fast convergence and good stability through case computations. In the end, the performances of non-isothermal rich gas flow in the undulating offshore long-distance pipeline in China is investigated by analyzing the profiles of pressure, temperature, velocity and liquid holdup. The predicted results in this study agree well with the operating data. The theoretical analysis, and comparison of calculated results with operating data and OLGA indicate that the presented model for analyzing rich gas flow behavior in small diameter pipelines looks reasonable.
Analyses of the Process Control and Technical Scheme of Urumchi—Lanzhou Multi-Products Pipeline
Authors: Gong Jing , Zhang Qiang
Published: July 2009

The Urumchi—Lanzhou multi-product Pipeline (China western multi-product pipeline, CWPP) is characterized by long distance, multi-delivery points, severe undulating terrain and high-required running conditions. According to technical characteristics and automation level of the stations, the various running states are analyzed, and the process control principles and accident handling methods are also identified. Based on the terrain and sequencing of the transportation process, the pipeline shutdown principles and methods are determined. Calculation methods of the shutdown pressure are proposed considering the temperature drop caused by shutdown. The dynamic optimal control methods of control valves at pressure-reducing stations are also presented considering that multi-product pipeline through the different points with a large drop height can be analyzed by lots of different control modes. Based on the analyses of operating parameters, it indicates that the application of control principles and methods offers guarantee for the pipeline safety and economic operation.
Microstructure, Mechanical Properties and SSC Susceptibility of Multiple SMAW Repairs in Line Pipe Girth Welds
Authors: Vega Oscar E. , Hallen Jose´ M. , Villagomez Agusti´n , Contreras Antonio
Published: July 2009

Girth welds of seamless API X52 steel pipe containing multiple shielded metal arc welding (SMAW) repairs and one as-welded condition were studied. Microstructural characterization, mechanical behavior and sulfide stress corrosion cracking (SSC) susceptibility of the welded joints were evaluated by means of optical and scanning electron microscopy, hardness, tension, Charpy-V impact resistance and slow strain rate tests (SSRT). The results of this work indicate that increasing the number of welding repairs promotes grain growth in the heat affected zone (HAZ). The yield strength (YS) and ultimate tensile strength (UTS) for the different welding repairs satisfy the specified minimum values of the material. Significant reduction in Charpy-V impact resistance with the increases of the number of repairs was found in the coarse grained heat affected zone (CGHAZ). A high susceptibility to SSC was exhibited by the welded joints and the intercritical heat affected zone was the most susceptible area to SSC.
A Review of Pipeline Integrity Assessment and Some Progress in China
Authors: Lu Minxu
Published: July 2009

In the paper, the significant progress of pipeline integrity assessment for oil and gas pipeline in China was expounded. The pipeline integrity assessment for oil and gas pipeline can be categorized as three aspects: the safety assessment of geological disaster, the integrity assessment for defect containing pipeline, and the effective protective life prediction for protection coating layer. The pipeline integrity assessment technology can be further categorized as remaining strength assessment and remaining life prediction for defect containing pipeline. The defects can be classified as five types for remaining strength assessment and three groups for remaining life prediction. Up to now, we have carried out integrity assessment for over twenty in-service oil and gas pipelines. In the near future, we should focus a certain extent of attention to the geological disaster assessment and effective protection life prediction for coating layer. In the paper, three typical strength remaining models and three service life prediction methods were also introduced briefly. The recent research status quo in China was also reviewed for soil induced stress corrosion cracking and some new interesting phenomena was also reported here. Finally, one typical application example was introduced, that fully accounted for the importance of safety assessment of oil and gas pipeline.
On the Simulation of Multiphase Flow Containing Hydrate Particles
Authors: Zhao Jian-Kui , Gong Jing
Published: July 2009

The article presents a mathematical model to simulate steady multiphase flow containing hydrate particles. The approach is based on the one-dimensional two-fluid model in which the two phases consist of the gas and the mixture of the liquid and hydrate particles. That is to say the hydrate particle and liquid phase are treated as pseudo-fluid. When a compositional model is used to simulate two-phase flow, it is required to couple mass, momentum, energy equations and equation of state, then the pressure and temperature and mass transfer between gas and liquid phase along the pipeline can be simulated. In the steady condition, it’s assumed that the composition of fluid is unchangeable along the pipeline and the flow can be described by pressure and temperature. In this paper, calculation method of gas-liquid two-phase flow which required a double iterative procedure of pressure and temperature respectively was improved. Liquid holdup and pressure drop were calculated by momentum equation. Enthalpy balance equation was substituted by explicit formulation of temperature calculation which meant that the loop of temperature was not required. So the calculation speed was enhanced. With strict flash calculation the following items were determined: the amount of hydrate; phase number; the location that hydrate appeared; flow rate and molar component of gas phase and liquid phase. Then thermodynamic quantities were calculated with proper relational expressions.
Design and Construction of 42” Liquids Pipeline Batch Pig Facilities
Authors: Kratsch Robert W.
Published: July 2009

Enbridge’s current major expansion called “Southern Access” is a 42″ liquid crude oil pipeline running 321 miles from Superior, WI to Delavan, WI in 2008 and continuing another 133 miles to Flanagan, IL in 2009. As part of the goal to achieve and maintain a high quality pipeline system, an automated batch pig system was required to remotely launch the batch pigs, operated from the Control Center in Edmonton, Alberta, Canada. The project team has designed and developed a unique batch pig system that allows the loading and unloading of multiple pigs. The 42″ pigs can be remotely launched or received one at a time without having to open the pig launcher or receiver to atmosphere. These facilities allow pigs to be launched remotely, separating the various crude types being transported. The launcher and receiver have been designed to accommodate remote launching or receiving up to 4 pigs without having to open the traps. The facilities are designed for quick loading and unloading of the launcher and receiver to reduce the time the trap is open and reduce labor requirements. The receiving facilities incorporate pig washers and a pig maintenance shop to service the pigs as they are received. Specialized material handling equipment has been engineered to facilitate the safe and efficient movement of the pigs used for this operation. The launcher and receiver barrels can also be utilized for routine cleaning and inspection operations. This paper discusses the key features and challenges of the design and construction of the batch pig systems implemented for the new 42″ liquids pipeline. Of particular interest are the practical requirements included in the design for operation of the facilities in a safe and efficient manner.
Prediction of Wax Deposition of Crude Using Statistical and Neural Network Methods
Authors: Huang Qiyu , Ma Jun
Published: July 2009

Prediction of wax deposition rate of crude oil using statistical and neural network methods is presented. Wax deposition in the pipeline is an important issue for crude oil transportation and is a complicated process. It depends on the dynamic viscosity of the crude oil, shear stress, temperature gradient, concentration gradient of wax molecules on the wall. By virtue of oil wax deposition data from laboratory experiments, we train the neural network to learn the non-linear relationship between the influential factors and the wax deposition rate. Comparison of prediction results from a linear regression model and the neural network model is carried out to examine the feasibility of using neural network methods to predict wax deposition.
Research and Application of Drag Reducer for Oil Products
Authors: Guan Zhongyuan , Liang Jinghua , Liu Chunyang , Chang Weichun , Zhu Feng , Peng Shiyao
Published: July 2009

Taking the exact demands of chemical additive components added in oil products into account, it is necessary to prepare a drag reducer both with desirable functions and pure composition for oil products differing from that for crude oil. However, that is evidently difficult. This article presents the research and application of a newly-developed drag reducer for oil products, which is innocuous to oil products and easy to handle in its applications. The preparation of the drag reducer was based upon a series of integrative techniques involving adsorbent purification of monomers, implementation of bulk polymerization at low temperatures and ultramicro grinding of polyalphaolefins at normal temperatures. Simultaneously, the drag reducer can be manufactured in different scales by purpose-made equipment system with a little manual operation on safe, reliable, efficient and convenient base. The application test of the drag reducer was conducted successfully and has been commercially applied in Lanzhou-Chengdu-Chongqing Oil Products Pipeline. The application results for the pipeline showed that this drag reducer, as a feasible and available technical method, was not only positively helpful to increase the flow rate of Lanzhou-Chengdu-Chongqing Oil Products Pipeline, but also of great significance for other oil products pipelines in throughput increase and energy saving.
Metallurgical and Process Parameters for Commercial Production of High Toughness API-X80 Grade Hot Rolled Strips
Authors: Kim Kisoo , Bae Jin-Ho
Published: July 2009

While API-X80 grade UOE pipes have been increasingly applied during the last decades, the usage of hot rolled API-X80 grade for spiral-welded pipes have been limited. This is partly due to metallurgical barriers which are the anisotropy of mechanical properties and strength drop after pipe forming. Manufacturing conditions and metallurgical parameters have been studied to overcome theses barriers in this work. Also, the effect of both size and distributions of M/A constituent on the upper shelf energy measured from Charpy tests have been investigated. In this paper, the development of API-X80 hot rolled strips have been reviewed, and production results of 12,000MT API-X80 grade for a line pipe project has been provided.
Implementation of an Integrity Management Strategy to Optimize Future Inspection, Maintenance and Rehabilitation Activities
Authors: Brown B. , Clausard C. , Wilde A. , Healy J. , Russell A. C.
Published: July 2009

A Canadian pipeline company operates a 12 inch, nominal wall thickness 5.08mm and 25 km long partially buried insulated pipeline that transports hot liquid oil from an oil refinery, supplying product to a customer in Canada. In addition to the economic importance, this pipeline crosses a city intersecting several high consequence areas (HCA’s). Therefore ensuring the public safety and reliability of the pipeline is critical. One of the primary threats to the integrity of the system is external corrosion associated with areas of damage to the yellow jacket external coating. In buried sections this is due to a combination of water ingress in the damaged coating and CP shielding in these localized areas. The above ground sections are at a higher risk since they are open to the environment and any water ingress can be replenished. This corrosion mechanism can lead to potentially high corrosion rates. Such localized damage is difficult or impossible to detect in above-ground surveys. In addition to routine above-ground surveys and site examinations, high resolution in-line inspection is a key component of the pipeline operator’s overall integrity management strategy. It is conducted at appropriate frequencies to confirm the condition of the pipeline and to optimize maintenance plans to ensure the future safe, reliable and cost effective operation of the pipeline. To date three in-line inspections have been conducted on this pipeline. This paper presents an innovative technique for conducting a detailed corrosion growth comparison of the three inspection data sets and demonstrates the practical use of this methodology to optimize the future integrity management strategy.
Utilizing Circumferential MFL for the Detection of Linear and Axially Oriented Metal Loss Anomalies in Pipelines
Authors: Grimes Joseph , Nunez de Alvarez Alberto
Published: July 2009

In-line inspection (ILI) technologies have advanced quite significantly since their first usage over 30 years ago. This has been even more evident over the last 5–10 years. Technological developments in electronics, computing power, combined with an increased and better understanding of complex physical applications have lead to the latest generation of in-line inspection technologies which have been commercially available over this same time period. The owner / operators of the liquid and gas pipeline systems are faced with an increased awareness of their aging infrastructures and they are looking to the experts and providers of the latest technological developments to assist them in their efforts to manage and maintain pipeline integrity. ILI has proven time- and time again to be the most useful and cost effective tool that pipeline operators have to ensure safe, reliable and economic operation of their pipeline system(s). One of the main challenges that the industry is currently facing is the early detection of long narrow, axially oriented defects in pipelines. There have been various efforts within the industry to accomplish the goal of producing an efficient system that is economically feasible as well as reliable. In an effort to meet the demand for an in-line inspection tool that can meet the challenge, ILI companies have developed different applications. Ultra-sonic tools have been researched, developed, and used commercially in an effort to detect axially oriented anomalies affecting both pipe body and longitudinal weld seam. However, a tool utilizing UT technology is highly dependant upon the pipe’s functionality and medium (gas / liquid), and thus, is prone to incomplete and/or unacceptable survey data. Taking this into account, the utilization of UT technology for these purposes can be very costly with limited results. Because of the limitations and issues that UT tools experiences, ILI providers also researched the feasibility of utilizing proven MFL technology in this application. After proper development and testing, Circumferential Magnetic Flux Leakage technology was released for the inspection of pipelines — specifically, pipeline systems that were in need of longitudinal seam weld inspection. ROSEN’s solution to this challenge is the Axial Flaw Detection (AFD) tool. The AFD tool utilizes Magnetic Flux Leakage (MFL) technology by applying a circumferential magnetic field (CMFL), as opposed to the traditional axial oriented application of the field, to the pipe wall in order to detect and characterize anomalies which are linear and/or axially oriented that a typical MFL tool would under grade or not even detect. This article is meant to give the reader a better understanding of the technology as well as the development process of complex in-line inspection in today’s comprehensive and demanding pipeline industry. It will also provide historical findings within controlled environments and statistics from dig verifications from actual surveys.
The Post-Rapanos Predicament: An Application of the Jurisdictional Determination Form
Authors: Straub Craig A. , Hale Allan M.
Published: July 2009

On June 5, 2007, the Environmental Protection Agency (EPA) and U.S. Army Corps of Engineers (Corps) issued joint guidance (herein the Rapanos Guidance) interpreting the U.S. Supreme Court’s divided Rapanos v. United States decision on the geographic extent of regulatory jurisdiction under Section 404 of the Clean Water Act. The technical document, “Jurisdictional Determination Form Instructional Guidebook” uses ambiguous language regarding implementation of the guidance manual. Pursuant to the Rapanos guidance, traditionally navigable waters (TNW), relatively permanent tributaries to these waters, and wetlands directly abutting such tributaries are “categorically” jurisdictional, while non-navigable tributaries that are not relatively permanent, wetlands adjacent to such tributaries, and wetlands that are adjacent to but do not directly abut a relatively permanent non-navigable tributary, are jurisdictional only if they have a “significant nexus” to a TNW. A critical issue for permit applications is whether the proposed activity will be subject to a categorical assertion of regulatory jurisdiction, or to a more involved “significant nexus analysis.” The scientific and environmental analyses of permit applications encountering a significant nexus analysis is designed to undergo additional review by the EPA. At the present time, the Guidance is deficient in providing definitive instruction for determining whether a significant nexus is present between a non-navigable tributary with non-permanent flow and a TNW. Our project allowed implementation of the Guidance and involved the installation of 264 miles of pipeline and permit negotiation with three separate Corps districts. Assessment of 483 streams and 189 wetlands was performed using the newly developed Jurisdictional Determination Forms. An interdisciplinary team approach was developed by integrating the knowledge bases of geographers and ecologists. Databases and maps were developed to allow collective assessment of potential waters of the U.S. within the context of the Rapanos ruling. Because of the Guidance’s ambiguity, it was necessary to develop a defensible approach with detailed concepts and terms to adequately implement the Jurisdictional Determination process to the satisfaction of regulators responsible for the implementation of the jurisdictional determination guidance manual.
High End Inspection by Filmless Radiography on LSAW Large Diameter Pipes From EUROPIPE
Authors: Kersting Thomas , Liessem Andreas , Oesterlein Ludwig , Schuster Stefan , Schoenartz Norbert
Published: July 2009

Pipes for transportation of combustible media are subject to the most severe safety requirements. In order to guarantee best performance during construction and long term services the level of quality and the productivity are continuously increased. After many years of experience with the Filmless-Radiography (FLORAD) for internal process control (detection of typical weld seam defects like slag and pores), EUROPIPE has eventually invested in the digital X-ray inspection technology for the final release. Therewith the classic X-ray film has been replaced, the environmental impact due to chemicals reduced and the complete NDT process enhanced. By the availability of safe digital images via computer network it became in addition much easier for third party inspectors to monitor the release process. Furthermore the use of a professional data storage system guarantees a safe and traceable long term archival storage with a quick access to all data within minutes. The new installation consists of two separate X-ray chambers. In each chamber two digital detector arrays (DDA) and two X-ray tubes are installed to inspect the weld seam at the pipe ends and areas having indications from the automated ultrasonic testing. EUROPIPE is the first company which has implemented this technology in a highly automated serial production of large diameter pipes.