bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of the Crack-Arrest Toughness of the Pipeline Steel X 70
Authors: Felber S. 
Published: October 2016

The resistance of a material against fracture is influenced by its behaviour during the three possible steps of the fracture process, which are crack initiation, crack extension, and crack-arrest. It is the task of materials testing, especially of fracture mechanics, to find out the relevant parameters. To stop a crack in a pipeline in order to limit the crack length it is of great interest to know the crack-arrest toughness, KIa, of the material used.
There are two main possibilities to stop a crack in a pipeline: The first one is to apply special crack arrestors, and the second one is to use a material with a high crack-arrest toughness. The first possibility is rarely realized, and so it is of great interest to gain knowledge of the fracture toughness values of the pipeline steels employed. In the past, big specimens, like Robertson plates for example, were used for the determination of the crack-arrest toughness, KIa, but they are very expensive and so nowadays they are replaced by small specimens like:
1st, the three-point bend specimens (specimens used in a proposal published by TVFA, University of Technology, Vienna),
2nd, the compact-crack-arrest specimens (specimens of the standard test method ASTM E 1221) and
3rd, the full-thickness compact-crack-arrest specimens (specimens proposed in the test method of Ripling and Crosley).
This work deals with the determination of the crack-arrest toughness, KIa, of the base material, the weld metal and the heat affected zone of a weld of the pipeline steel X 70. For this purpose tests were performed with each of the three materials, employing each of the three mentioned test specimens. Finally, this work contains a discussion and a comparison of the measured crack-arrest toughness values.
High Temperature Pipeline Coatings Using Polypropylene Over Fusion Bonded Epoxy
Authors: Norsworthy Richard 
Published: October 2016

The following is a discussion of test results and application techniques for high temperature pipe line coatings of polypropylene over fusion bonded epoxy. Recent tests to internal temperatures of 150°C (300°F) indicate these coatings, when applied properly, will perform well at these temperatures. Test results from several different tests are included.
Repairs, field joints and bend coating with these type coatings are discussed. Problems during and after application are summarized. Use of well written specifications and experienced, dedicated inspectors add to the quality of the coating process. As industry moves to hotter and hotter production, these factors become even more critical in the pipeline coating process.
Pipeline Accident Statistics: Base to Pipeline Rehabilitation
Authors: Chis Timur 
Published: October 2016

The climate in which pipeline companies operate continues to change. Industry failures, related to public safety and environmental concerns, are now front page news.
New and proposed regulations such as drug and alcohol testing of employees, instruments internal inspection and standardise oil spill response plans, are modifying the way pipeline companies operate. Paralleling this influences, the market place is also changing.
Declining domestic production refinery closures and new specification for refined products are altering the pipe line distribution system.
All of these changes are presenting new opportunities and many challenges.
In 1995, when CONPET S.A.PLOIESTI Formalised Pipeline Integrity Program, the reasons for the program were to:
- What is the location to pipeline rehabilitation?
- What is failure probability?
This paper reviews some aspects of the pipeline accident statistic to the CONSTANTA DIVISION parts of CONPET S.A.PLOIESTI.
Main Principles on Analysis and Design of Buried Ballasted Pipelines on Marshes
Authors: Dimov Leonid A. , Vershinin Valeriy N. 
Published: October 2016

State of stress and deformation of buried oil-gas pipelines under, operation must meet appointed requirements on strength, deformability, general stability, etc. Fulfilment of those requirements while designing main and field pipelines in conditions of marshes and marshy soils is very problematical. The cause lies both in weak knowledge of peat reaction to longitidual and lateral displacements of the pipe and in impossibility on account of that to analize the pipe state of stress and deformation taking into consideration the joint pipe-soil deformation.
Wide research into pipe-peat interaction has been carried out at the Institute of Construction (Republic of Komi, Russia). In the paper there are enumerated main principles on design, analysis and engineering of buried ballasted pipelines on marshes, which have been worked at the Institute. The practical value of the work results for improvement of pipelines reliability under operation is emphasized in the paper, too.
Techniques for Preventing Accidental Damage to Pipelines
Authors: Lothon Alain , Akel Samir 
Published: October 2016

Following a survey of all of the techniques capable of preventing third-party damage to its gas transmission pipelines, Gaz de France has selected two of them, “Electromagnetic Detection” and “Positioning by Satellite”.
The first technique is based on detection of the magnetic field existing around transmission pipes excited by a driving current. A receiver is mounted on the excavation equipment to detect the magnetic field, thereby preventing any risk of hitting the pipe.
The second technique consists in locating excavators by satellite. Each excavator needs to be equipped with a GPS beacon to know its position. Using the map of the transmission network stored in data-base form — i.e. digitized, the system calculates the position of the excavator relative to the pipes buried in its vicinity so as to avoid any accidental contact.
The main features, advantages and drawbacks of the two techniques are presented in this paper.
Drag Reducing Agent: A Multi-Use Tool for Liquid Pipeline Companies
Authors: Rew David H. , Sandman Steven R. 
Published: October 2016

The role of Drag Reducing Agents (DRA) at Lakehead Pipe Line (LPL) has expanded considerably in recent years. It is now a multi-purpose tool that helps manage electric power usage as well as having traditional capacity increase uses. Indeed, DRA is now an important part of operating the LPL system.
This paper examines the multiple uses of DRA as used by LPL. It also describes the structure of the DRA program within the company and provides a summary of “lessons learned” since the DRA program started at LPL in 1991. This information should be useful for anyone who is considering implementing a DRA program.
Pipeline Purging Principles and Practice
Authors: Johnson James E. , Svedeman Steven J. , Kuhl Christopher A. , Gregor John G. , Lambeth Alan K. 
Published: October 2016

Gas purging, a process of displacing one gas by another gas, occurs on a routine basis in the natural gas industry when pipelines are purged into and out of service. In a project sponsored by the Gas Research Institute and in cooperation with the American Gas Association (A.G.A.) the purging practices as outlined in the A.G.A.’s Purging Principles and Practices manual are being reviewed because many of today’s pipeline purging operations occur under conditions not addressed directly in the manual. The program focus is on the purging procedures outlined in Chapter 8 of the manual entitled Gas Transmission and Distribution Pipes.
The technical objective of the project is to develop an understanding of the scientific principles upon which safe, practical purging practices can be based. Direct displacement and inert gas slug purging operations are explained in terms of dispersion and mixing parameters and their relationship to the gas velocity. Field data is compared to the results of an analytical mixing model. Computer software for planning safe and cost effective pipeline purges has been developed. Finally, recommendations for revising Chapter 8 of the A.G.A. manual are presented.
Design and Construction of the World’s Longest Liquid Sulphur Pipeline
Authors: Baron John J. , Lawrence J. E. (Ted) , King Graeme G. 
Published: October 2016

Sulphur is extracted from sour gas at Shell’s Caroline Gas Plant in the foothills of the Rocky Mountains in Alberta, Canada. A buried pipeline carries the liquid sulphur 41 km cross-country to a railhead at Shantz. Sulphur is difficult to handle by pipeline because it remains solid at temperatures up to 118.9°C. Challenges posed by high operating temperatures necessitated many innovations during design and construction.
The liquid sulphur pipeline is built from two coaxial pipes. The inner pipe carries liquid sulphur while the annular space carries circulating hot water under pressure. The inner pipe has a diameter of 219.1 mm (NPS 8) and the outer pipe has a diameter of 323.9 mm (NPS 12) with 80 mm of high density urethane foam insulation. A hot water return line with a diameter of 168.3 mm (NPS 6) and 50 mm of insulation completes the loop for the continuous circulation of hot water. Two hot water heaters are installed, one at each end of the line. The system can carry between 0 and 5,100 tonnes of liquid sulphur per day on a continuous basis, and can be easily expanded to 8,000 tonnes per day by adding extra pumps.
Construction of this unique pipeline required skilled workers operating under sometimes difficult climatic conditions. The route winds through hilly terrain in the foothills of the Rocky Mountains and crosses under three major rivers. Careful planning led to the successful completion of the world’s longest liquid sulphur pipeline on time and under budget. The pipeline has now been operated successfully for more than three years.
Effect of Impeller Cutdown on Developed Head
Authors: Yedidiah S. 
Published: October 2016

This paper discusses the manner, in which a new approach towards calculating the head developed by a centrifugal impeller can be applied towards predicting the head developed by a pump with a cut-down impeller.
A comparison with actual test-data demonstrates, that this approach is capable to produce more reliable results, than any of the presently known methods.
Interrelationship Between the Efficiency Characteristics and the Pressure Head Gradients Among Axial Flow Pumps
Authors: Tanaka Takaharu 
Published: October 2016

There is a correlation between the efficiency of the pump to the head produced. On the axial flow pump, whose efficiency characteristic is favorable, the pressure head gradient between the impeller inlet and the outlet sections, at an equivalent flow rate, may become larger than that for the less favorable axial flow pump. This fundamental interrelation may be held in the flow passage regardless to the flow rate whichever they are operated at design or off design flow rate.
There may be a direct correlation between the efficiency of an axial flow pump and the ratio of the discharge valve cross section divided by the pipeline cross section. The smaller this ratio is the better the pressure head gradient is for the same flow rates. This ratio may be useful to estimate relative grade of heads, pressure head gradients, internal flow conditions, and efficiency characteristics among axial flow pumps.
Sensitivity of Torsional Analyses to Uncertainty in System Mass-Elastic Properties
Authors: Murray Brad D. , Howes Brian C. , Chui Jonathan , Zacharias Valerie 
Published: October 2016

Shaft torque and corresponding stresses in a motor driven - direct coupled - reciprocating compressor system, are significantly influenced by the system’s mass-elastic properties. Uncertainty in the system’s mass-elastic properties will therefore translate into uncertainty in the calculated system stresses. Three case studies provide the reader with an appreciation for the importance of defining uncertainty bands in the mass-elastic properties of a torsional system.
The case studies are followed by a theoretical discussion section. The reader is introduced to the concept of torsional resonance, uncertainty in calculated system torsional natural frequencies is defined, and the relative influence that specific system mass-elastic properties have on the overall system is discussed. A full compliment of system mass-elastic uncertainties is presented.
Reducing the Life Cycle Cost of Swing Check Valves
Authors: Roorda O. , McNeill J. D. , Wright M. 
Published: October 2016

Within the oil and gas industry there is an emerging trend to estimate expenses for pipelines and system components using a Life Cycle Cost (LCC) basis. This paper describes a new sizing model for swing check valves that can assist in significantly reducing the LCC of the valve. The incremental fuel cost of the compressor arising from pressure loss across the valve is the largest component of the valve’s LCC. The valve’s pressure loss can be minimized by correct valve sizing ensuring full valve opening under normal flow conditions.
This new sizing program, applied to an NPS 20 natural gas pipeline, can result in cost savings in the order of two times the capital cost of a swing check valve when compared to traditional sizing methods.
The pressure loss across the valve is primarily determined by the opening angle of the valve disc during steady state operation. A steady state valve model was developed and formed the basis for a sizing program for swing check valves. The sizing program assists in optimizing the valve for specified operating conditions. Within margins, the valve opening characteristic can be optimized by adjusting the valve sizing parameters such as valve size, disc weight, counter balance mass and position for a specified set of operating conditions.
The LCC of a swing check valve can be further reduced by up to 45% through optimization of the valve design. The sizing program was used in a parametric study to assess the areas relevant in the design optimization of the valve. To further reduce the LCC of swing check valves, research should focus on improving the internal flow profile of the valve, reducing disc weight and eliminating the need for counter balance weights through improving low friction seal design.
Pipeline Control System Applications Targeting Business Objectives
Authors: Feniak John E. , King Dan A. , Mensik Michal 
Published: October 2016

Today’s increasingly competitive markets require new levels of reliability, flexibility and cost performance from gas transmission pipelines. One method that pipeline companies can use to address these business objectives is to target station and turbomachinery control system design specification, retrofits and integration.
State of the art control tools and technologies have placed turbomachinery control engineering within the grasp of the end users. NOVA Gas Transmission Ltd. (NGTL) has taken advantage of this to specify, design, and implement integrated control systems that best address their business needs.
This paper explores the end user perspective on applying control system technology to both new and existing compressor stations. The specification of new units and control retrofits are described. The resulting increase in system reliability and flexibility, and reduced maintenance costs is also presented.
Development of a Simulator-Based Training Program
Authors: Salerno Charles R. , Radu Edith , Persic Nerino , Schmitz David B. 
Published: October 2016

This paper presents the Con Edison Gas Control experience in developing a simulator-based training program.
The simulator-based training is now part of the Con Edison safety training as it allows the gas controllers to get familiar with abnormal and emergency conditions and learn to react promptly to contain the problem.
The process of developing a training course required a sustained and dedicated effort. A number of iterative steps were necessary as we learned that the development of models and scenarios for training is a specific activity which is different from other activities such as simulator-based studies.
The simulator-based training course we developed has two parts: basic concepts and Con-Edison specific lessons. Each part required a different lesson format and issues related to the development of the lessons are discussed.
Elements of Comprehensive Pipeline Optimization
Authors: Short Michael , Meller Steven H. 
Published: October 2016

It is well known that algorithms exist for reducing pipeline operating costs. These algorithms are exact for ideal pipelines and need to be modified to provide solutions for the real world. The issues include pipeline configurations, utility cost structures, and quantification of hydraulic safety. Successful modification requires understanding of the pipeline operating environment (on-line operations) and must be linked to pipeline operating conditions.
Many of the optimization tools available to the pipeline industry today are based upon a dynamic programming algorithm attributed to Bellman. The costs of unit operations are balanced with the energy absorbed in heat due to frictional and other losses. This is carried out in such a way as to reduce the massive computational effort of an exhaustive solution search to a manageable level. For a pedagogical treatment of the problem, this is adequate. However, there are many significant factors which need to be added into and around this basic calculation. First, an algorithm with electrical cost factors only cannot evaluate penalties associated with poor hydraulics choices. Demand grouping, parallel pipelines, large amplitude pressure cycles, look ahead, and unit cycling also can and should be included in a full analysis.
A modification to Bellman’s algorithm for non-linear pipeline configurations and electrical contracts will be developed and discussed in the context of a real-world petroleum pipeline operation.
The Role of Geotechnical Investigation for Directionally Drilled River Crossings
Authors: Barlow J. Peter , Cavers Drummond S. 
Published: October 2016

The use of directional drilling techniques for pipeline river crossings has increased sharply over the past few years in Canada and the United States. Improvements in drilling technology and increased experience among a growing number of specialty contractors has helped to reduce the cost of directionally drilled installations and to reduce the risks. The advantages associated with reducing disturbance of the water course by the use of directional drilling are often considered to outweigh the additional costs typically associated with the method.
While the advantages of using directional drilling methods are compelling, the technique is not universally suited to all river valleys due to considerations of valley topography and geological setting. Specifically, there are certain geological and geometrical conditions that make the method completely unsuitable. In other cases, the geology beneath the river channel and the valley geometry may present a challenge to a drilled installation that can be overcome with adjustments to the design and drilling technique if anticipated.
The implications of encountering unfavourable geological conditions during construction can be significant. The implications can range from substantial construction cost overruns up to several times the original bid price, to installations that cannot be safely put into service and must be abandoned. Under certain geological and geometrical conditions, the risk of blowout or fluid leakage to the water course during installation may be significant.
The role of geotechnical and subsurface investigations to identify geological conditions prior to commencing construction is more critical for a drilled installation than for conventional trench techniques, as the consequences of encountering unanticipated conditions can be much more severe with drilled crossings. In addition, a trenched crossing is inherently more flexible than a directional crossing in terms of the ability of the contractor to adapt to different conditions than those anticipated at the start of the work.
A Case Study of Pipeline Route Selection and Design Through Discontinuous Permafrost Terrain in Northwestern Alberta
Authors: Wiechnik Cory , Boivin Raymond , Henderson Jim , Bowman Mark 
Published: October 2016

As the natural gas pipeline system in Western Canada expands northward, it traverses the discontinuous permafrost zone. As the ground temperature of the frozen soil in this zone is just below freezing, it can be expected that within the design life of a pipeline the permafrost adjacent to it will melt due to the disturbance of the insulating cover by construction activities. Differential settlement at the thawing frozen/unfrozen soil interfaces gives rise to pipeline strain. Based on the calculated settlement and resulting strain level, a cost effective mechanical or civil design solution can be selected to mitigate the differential settlement problem. Since these design solutions can be costly, it is desirable to combine them with a pipeline route that traverses the least amount of discontinuous permafrost terrain while minimizing the overall length of the pipeline.
This paper will detail the framework utilized to select the routing for a package of pipeline projects in northwestern Alberta. The process began with a review of the state of the art in permafrost engineering in order to benefit from past experiences. Airphoto interpretation and terrain mapping were performed for potential pipeline corridors. Preliminary routing options through the corridors were chosen from this mapping information that minimized both pipeline length and amount of permafrost terrain traversed. The next step was to collect field data for each route that would determine the extent and characteristics of the permafrost. Essentially two sets of field data were collected: geophysical mapping of representative sections of each terrain type and physical sampling of the permafrost. Boreholes were located following field interpretation of the geophysical data to ensure they were optimally located to help in calibration of the geophysical data. Permafrost samples were tested in the laboratory for thaw settlement. Anticipated thaw settlements were used to estimate pipe strain levels. This information was then extrapolated for the entire proposed pipeline route and used to finalize both the pipeline route and the differential settlement design options. Monitoring sites will be instrumented to obtain data on the longer term performance of the pipeline, as well as for assessing permafrost degradation effects on the right-of-way such as settlement and impact on drainage patterns.
It is believed that the increased front end effort will result in lower operating costs and an overall reduced life-cycle cost. This basic design methodology can be applied to any project that traverses discontinuous permafrost terrain.
Relative Risk Assessment: The Competitive Advantage
Authors: Beighle Bruce D. , Gloven Mike P. 
Published: October 2016

Lacking complete and accurate data, many pipeline companies have adopted various forms of relative (index-based) risk assessment models(2) which help define their acceptable risk position based on available pipeline data, limited resources and corporate beliefs. Through this proven risk assessment process, company management establishes their unique risk algorithm by benchmarking variables which contribute to the likelihood of failure, and the associated consequences of failure, for all pipeline systems. This algorithm then acts as a pipeline data filter to identify pipeline areas at greater risk relative to others.
A progressive relative risk assessment process can change an operator’s safety and resource allocation culture, resulting in reduced pipeline failure rates, increased operating flexibility and improved financial performance.