bluuebunny/crossref_metadata_2025 huggingface dataset:
Technology Management Renewal at NOVA Gas Transmission
Authors: Cormier Randy C. , Dorling David V.
Published: October 2016

NOVA Gas Transmission Ltd. (NGTL) is an industry leader in successfully applying new technology to meet business needs. The company has had a formal technology development program since 1983 and invests approximately $5.5 million annually towards developing and implementing beneficial new technology. Over the years, this leadership has provided tremendous value to NGTL’s customers, shareholders, employees and the communities in which it operates.

In 1994, as part of the company’s re-engineering initiative, a high-level scoping effort identified several opportunities to further enhance the business value derived through the application of technology. To realize these opportunities, NGTL launched an effort to renew its processes for managing technology. Through this renewal effort, NGTL: 1) developed guiding organizational principles for managing technology, 2) established Key Technology Areas of focus, 3) re-structured its technology development organization, 4) leveraged best-practice concepts to improve the process of developing and implementing technologies, and 5) made significant progress in marketing the value of technological innovation across the organization.

This paper will highlight NGTL’s technology management renewal effort including its historical context and rationale, the process used and the major outcomes.
Route Selection for Project Success: Addressing “Feeling/Perception” Issues
Authors: Mohitpour M. , Von Bassenheim G. , Braun Ardean
Published: October 2016

Selecting a route for a pipeline right-of-way (ROW) generally consists of engineering (technical and economic), socioeconomic and biophysical components. To effectively select a route, simultaneous consideration must be given to all the components from the initiation of a project to the integration of all aspects of each throughout the route selection process. To successfully select a route which creates a win-win situation for all the stakeholders of a pipeline project, political/governmental issues, community and land owner views, public perceptions and other similar controlling factors (such as Safety, Health, Environment and Risk (SHER)) must be carefully analyzed and integrated into the process. It is the consideration of all these issues that will lead to a ROW which will provide a technically acceptable solution, which is at the same time the least expensive, economically viable and acceptable to the community it traverses.

This paper will provide an overview of route selection techniques (including new technologies) used and the process generally practiced by pipeline designers, highlighting controlling issues and optimization methods that need to be utilized in order to achieve a cost effective route selection. It provides details on significant “Feeling/Perception” issues that can either thwart or, by careful consideration of these issues, lead to a successful pipeline project. An example of such a route selection process will be provided on a project located in rough and mountainous terrain, that has significant regulatory/governmental, land, environmental, indigenous and geological issues.
Dual-Purpose Fibre Optic System Providing Simultaneous, Real-Time Communications and Distributed Vibration Sensing for Pipeline Applications
Authors: Tapanes E.
Published: October 2016

A proprietary fibre optic sensing technology has been developed and is capable of simultaneously utilising an existing fibre optic communication cable as an integrity-testing sensing cable, thus providing continuous, real-time monitoring of the fibre cable and any structure near the cable (ie., ground, tunnels, ducts, pipes, buildings, equipment, vessels, etc.). With this system, simultaneous fibre optic communications and real-time vibration monitoring was demonstrated using a wavelength multiplexed fibre system for a channel bandwidth of 500 MHz over 18 km of standard singlemode fibre. Real-time vibration monitoring was also demonstrated using standard singlemode and multimode fibre over lengths of 28 km and 53 km, respectively. Trials of the system are currently underway in Australia and the first commercial field installation with this capability is to be completed in mid-1998 in Indonesia. This paper highlights the benefits and potential of this dual-capacity system and details results obtained to-date.
Countdown to the Year 2000
Authors: Bachor Vernon W.
Published: October 2016

The Year 2000 problem, also known as Y2K or the Millennium bug, is an enterprise-wide issue that potentially touches all aspects of businesses and our personal lives. This paper is designed to heighten awareness of this critical issue and promote businesses to act.

This paper provides a primer on year 2000 issues for process control, with some pipeline-specific thoughts. The paper presents the potential impacts from the rollover, describes where to look for problems, outlines the methodology a year 2000 project should follow, provides guidance for vendor relations, and, finally, notes the critical processes for a pipeline.
Pipeline Isolation Tool
Authors: Jones David R. , Cooman Andre , Dyck John , Flatekval Gerry , Gotowik Horst
Published: October 2016

Maintenance procedures conducted on pipelines often require isolation of a section of the line. Valve replacement, tie ins, pipe replacement are a few examples of procedures which normally require the pipeline to be taken out of service and drained down, or solid material stops intrusively applied to the pipeline.

Pipeline isolation tools have been available and applied for many years; these tools required pressure differential or tethered control to activate and deactivate the isolating mechanism. While these tools were applied with success, there was no way to accurately monitor this early generation of tool for performance and determine with reliability whether the tool was properly set. These tools had the capability of performing one task, once the tool had completed its task, it was removed from the pipeline and readied for its next application.

A new isolation tool has been developed and proven for pipeline application and this paper will discuss the Multi-Set Isolation Tool (Iso-Tool), its unique features, development and application.
Use of Surface Pipeline Segments to Mitigate Slide Problems on the Fort Nelson Natural Gas Mainline
Authors: Cavers Drummond S. , McClarty Edward A.
Published: October 2016

Skid mounted surface pipelines have been used to cross four major creek valleys on the Westcoast Energy 762 mm Fort Nelson mainline where very large deep-seated slides are progressively failing. The surface pipeline segments range up to 2.2 km long and were used to cross very large slides on the creek approach slopes, or in one case, down valley sliding of the valley floor, which had resulted in major operational problems for the originally buried pipelines. The surface pipeline segments were used for slides where there were no other options for a conventional buried pipeline. During the studies to support the design of the surface pipelines, comprehensive geotechnical investigations included drilling, installation of slope indicators, and electric piezocone penetrometer testing to monitor subsurface pore water pressures and to detect deep seated slide surfaces. Typical peak movement rates of the slides varied to a maximum of several meters per year. The unstable soils were predominantly medium to high plastic silty clay tills and high plastic glaciolacustrine clays with residual internal angles of friction of 7.5 to 8.5°.

The pipelines were placed on pressure treated timber skids on graded rights-of-ways (RoW) with comprehensive surface and subsurface water control. Aerial clear span crossings were used across the watercourses with geogrid reinforced abutments on the unstable soil. Geogrids were also used to add stability to structural fills and to reinforce an area of the RoW subject to encroachment from a rapidly moving earth flow up to 6 m deep. The general maintenance and operational guidelines are also discussed. Provincial and Federal regulatory concerns and their abatement are presented and discussed. Over the past five years of operation of the pipelines, one of the slopes moved 1.5 m in a twenty-four hour period and related total movements left a 5 m high head scarp on the RoW. Displacement of soil and areas of thrusting resulted in unsupported pipe spans of 35 m with negligible deleterious impact on the pipeline. This magnitude of movement would have almost certainly caused a failure of the original buried line. All of slopes have continued to move and would have caused a varying magnitude of operational problems had the pipelines still been buried.
Pipeline Exposure at River Crossings: Causes and Cures
Authors: Sawatsky Les F. , Bender Michael J. , Long Dejiang
Published: October 2016

Erosion is a common problem at pipeline watercourse crossings. Watercourses are naturally vulnerable to erosion but the risk is particularly acute after sub-soil and armour materials have been disturbed by trenching and backfilling during pipeline construction.

The process of pipeline exposure at watercourse crossings can be grouped into these types. One common type of erosion phenomenon is episodic exposure resulting from general and local scour. This is associated with temporary river scour during flood events. It includes general scour involving temporary lowering or the entire river bed during high flows, as well as local scour which involves development of a scour hole during high flow events at a predictable location on the river bed. River engineers have adopted various design methods to ensure sufficient pipeline burial depth which minimizes pipeline exposure due to such periodic occurrences.

A second type of erosion phenomenon causing pipeline exposure is progressive river channel bed and bank erosion. This is not a function of a single event but occurs periodically, resulting in progressive removal of pipeline cover. Progressive erosion at pipeline crossings includes riverbed degradation, bank erosion and growth of gullies. River bed degradation (progressive river bed lowering) is a complex phenomenon associated with the stage of geomorphic development of the drainage basin. Its prediction is based on a sound understanding of sediment supply, river hydraulics and river outlet conditions. Bank erosion is a common occurrence and is readily observed. It may be a continuous or episodic occurrence and is often related to the river’s tendency to change its meander pattern, cross sectional shape or bed level. Growth of gullies is a very common cause of erosion at pipeline crossings and results from changes in land use, soil composition, and landscape drainage networks. Techniques for predicting progressive erosion are not well developed and widely understood. As a result, progressive erosion is a common cause of erosion and even pipeline exposure at pipeline crossings of rivers, streams, and gullies.

A third mechanism of pipeline exposure is river avulsion. This is often associated with a tortuously meandering channel, a steep braided channel with a wide flood plain or an immature channel on a delta.

Methods of avoiding or controlling erosion are based on a sound understanding of causal factors. Each river crossing location is unique and the local risks of pipeline exposure must address specific local conditions. Methods of estimating the risk of local and general scour, progressive erosion, and river avulsions are discussed. Methods of mitigating erosion at pipeline crossings include proper siting of pipeline crossings, deep burial, conventional armouring and a combination of bank toe protection and upper bank vegetation cover.
Can Advanced Repair and Maintenance Technologies Prevent Machines From Failing?
Authors: Mugford James R.
Published: October 2016

Relatively low cost, easy to use, failure prediction technologies have empowered the maintenance department and have helped to change its position within plant organizational structures. Organizations that have embraced these new technologies and maintenance philosophies have helped to transform maintenance from a cost center into a strategically important department that has a material effect on profitability and competitiveness. As might be predicted, the rapid adoption of these failure prediction technologies is reducing the number of machines that are failing and having to be repaired. With fewer machines requiring repair, equipment repair shops are having to change to adapt to this new reality. In the near future fewer repair shops will exist and the ones that remain will be characterized as being high tech organizations with engineering, redesign and advanced repair process capabilities. These “repair shops of the future” will focus their energies on redesigning and then repairing chronically troublesome machines that have had the tendency to fail on a re-occurring basis. This paper will discuss these developments and show how they are reducing, and in some cases eliminating, the catastrophic failure of industrial plant machinery.
Application of the Quartz Crystal Microbalance to Corrosion Investigation
Authors: Sun Hejian , Donini John C. , Michaelian Kirk H. , Papavinasam Sankara , Revie R. Winston
Published: October 2016

The quartz crystal microbalance (QCM) provides an extremely sensitive technique for detecting small changes in mass and viscosity on the quartz crystal surface. QCM can be used in oil, gas or water without the problems of high solution resistance.

In order to use QCM to model pipeline corrosion, an iron quartz crystal electrode was prepared using an electrodeposition method. The reproducibility, effectiveness and accuracy of the iron QCM were tested in salt solution. The adsorption of amines was studied to investigate their effects on the corrosion behaviour of the iron QCM.
Repairing Pipe Defects (Cracking, Arc Burns, Corrosion, Dents) Without Operational Outages Using the PETROSLEEVE Compression Sleeve Repair Technique
Authors: Smyth Robert J.
Published: October 2016

Non-serviceable defects, such as cracking, dents, corrosion, or mill defects, are found in operating pipelines. Past methods to repair these defects have included removing the defect, welding a pressure containing sleeve, or, for corrosion, installing either a mechanically tightened or fibreglass reinforcing sleeve. These methods involved potential system shut downs, potential loss of throughput, and in some cases welding to the carrier pipe.

The PETROSLEEVE compression sleeve repair system consists of installing steel plate material that is shaped and sized to encircle the carrier pipe. The repair is completed while the carrier pipe continues to operate at the pipeline’s operational pressure.

Following installation, the pipe and sleeve act as one unit, expanding and contracting with pressure changes. Depending on the installation parameters, the repair sleeve can be installed so that compressive stresses are maintained in the pipe for all pressure operating ranges.

This repair method does not require any welding to the operating pipeline. It can be installed when the carrier pipe is at maximum operating pressure.
Estimation of Measurement Errors
Authors: Bhatia Arti , Mangat N. S. , Morrison Tom
Published: October 2016

A check of the measurement ability of the tools used to assess the corrosion on a pipeline is an important aspect of a maintenance program. In this paper a statistical method of determining the errors of measurement instruments is examined.
EMAT Generation of Horizontally Polarized Guided Shear Waves for Ultrasonic Pipe Inspection
Authors: Gauthier Julie , Mustafa Vasile , Chabbaz Ahmad , Hay D. Robert
Published: October 2016

In this work, an ultrasonic guided wave inspection technique was evaluated to detect and locate defects in pipes using SH (Horizontally polarized Shear) plate waves. Electromagnetic Acoustic Transducers (EMATs) were designed and constructed for bi-mode SH waves applications. These probes were used to generate a single mode at a time. Advantages of SH waves, guided by the wall surfaces for circumferential propagation and full volume inspection, are demonstrated in the pulse-echo setup. Mode selection criteria were investigated to tune the SH waves to the geometry of the inspection specimen Examples of mode selection based on the interaction characteristics of SH wave modes with a defect are described. An application of multi-mode inspection for geometrical parameter evaluation (length, depth and orientation) of individual cracks was also demonstrated. The experimental work was performed on cylindrical steel pipe samples having several types of defects ranging from through wall cracks to shallow cracks (10% of wall thickness) both in the circumferential and longitudinal directions. Results from laboratory investigation of the influence of defect depth and orientation on reflectivity of various modes of SH waves are reported. Multi-mode SH-wave inspection is shown to be capable of detecting shallow discontinuities (microcracks) and of locating defects accurately. Inspection results on a pipe section are represented as 3-D images with B-Scan projections and their interpretation is discussed.
High-Temperature, High-Pressure Rotating Electrode System
Authors: Papavinasam S. , Revie R. W.
Published: October 2016

Corrosion in high pressure vessels, such as pipelines, furnaces, and steam generators, is influenced by composition (material and atmosphere), pressure, temperature and flow. To simulate the corrosion conditions in high pressure vessels, a simple system is necessary to control the parameters and measure instantaneous corrosion rates. This paper describes a simple, compact, and relatively inexpensive high-temperature, high-pressure rotating electrode (HTHPRE) system that can be used to control simultaneously pressure, temperature, and flow, and to measure instantaneous corrosion rates using electrochemical techniques. It can be used with corrosive gases, such as H2S and CO2.
Mechanical Development of a NPS 36 Speed Controlled Pipeline Corrosion Measurement Tool
Authors: Evenson Robert S. , Jacobs Scott K.
Published: October 2016

High pressure natural gas pipeline companies conducting in-line magnetic flux leakage (MFL) corrosion inspection operations had to significantly reduce gas throughput velocity to accommodate MFL corrosion tool inspection speeds.

A large bypass, variable speed NPS 36 MFL corrosion inspection tool has been developed and run successfully in several high pressure natural gas pipelines without noticeable impact on operational throughput Active speed control enables the tool to run at speeds significantly lower than line velocity commonly experienced in high pressure natural gas pipelines. Unique mechanical innovations include large diameter flow bypass, an efficient speed control mechanism, variable drag backing bars and an independent bypass override system. A floating backing bar system ensures uniform sensor/wall contact for optimum data collection. Magnetic self-levitation of the backing bar results in reduced load on suspension and wheels providing more reliability and longer life to these components. Operating in higher line velocities infers higher possible tool speeds. This potential required development and construction of a more durable tool capable of higher speeds than typical MFL corrosion inspection tools. In this paper, development, testing and field operation of this tool is described.
NPS 8 Geopig: Inertial Measurement and Mechanical Caliper Technology
Authors: Michailides Phil , Deis Todd
Published: October 2016

The Geopig inspection tool provides pipeline operators with three-dimensional geographic and geometric information of their pipeline system. This paper reviews two of the primary technologies onboard the NPS 8 Geopig that are used to provide such information: the inertial measurement unit (IMU), which provides structural and geographical characteristics of the pipeline, and the mechanical caliper arms, which capture the internal diameter of the pipeline.

Recognizing the benefits of the tool and the data it can provide, Wascana Energy Inc. executed an inspection of a natural gas pipeline in Northern Alberta. The pipeline, which had buckled and sheared at a specific location, was inspected with the Geopig to further identify any other possible buckles, wrinkles or dents prior to re-commissioning. This paper reviews the inspection project undertaken, the data compiled by the Geopig, and the steps taken in the development of a predictive finite element model of the pipeline.
The Changing Role of Inspection
Authors: Grimes Keith
Published: October 2016

After thirty years of existence, on-line inspection using intelligent pigs has developed and matured into one of the most important tools for preservation of our pipeline assets world-wide. In that time it has undergone major changes to arrive at its current level of sophistication. The changing role of inspection and our expectations of it are addressed in this paper.
The Role of Pressure and Pressure Fluctuations in the Growth of Stress Corrosion Cracks in Line Pipe Steels
Authors: Wilmott Martyn J. , Sutherby Robert L.
Published: October 2016

Stress corrosion cracking of pipeline steels involves the interaction of a susceptible material with a corrosive environment under appropriate loading conditions. The stress exerted on pipeline steel is a combination of the internal operating or hoop stress, cyclic stresses due to pressure fluctuations within the pipe, residual stresses developed during pipe manufacture and pipeline construction, as well as other sources of stress such as stress concentrators like corrosion defects and geotechnical stresses.

As the internal pressure of an operating pipeline is never static the fluctuations in pressure result in cyclic loading of the pipeline material.

Whilst there are many stresses acting on a pipeline the predominant stress is the hoop stress created as a result of the internal operating pressure. In this paper experiments are described which are aimed at determining the effect of pipeline hoop stress on the growth of stress corrosion cracks under neutral pH conditions.

The propagation of stress corrosion cracks in pipeline steels at near neutral pH was studied under realistic environmental conditions. The impact of hoop stress on the growth of shallow surface cracks in an X60 pipeline steel was investigated at 40%, 70% and 100% of the specified minimum yield strength of the material. Crack growth rate is shown to be independent of the applied stress in the range studied for these shallow cracks. Cyclic stresses appear to be more important for crack propagation under neutral pH SCC conditions.

In light of the results obtained in this test program an attempt was made to characterize the pressure changes occurring on an operating gas pipeline. A computer program was developed to enable characterization of the pressure fluctuations for operating gas pipelines. The results of characterization of pressure histories from a number of operating pipelines are presented.
Prediction of Maximum Time for Delayed Cracking in a Simulated Girth Weld Repair
Authors: Malik Lalit , Pussegoda Lakshman N. , Graville Brian A. , Glover Alan G.
Published: October 2016

In a previous publication, the use of a simple two dimensional finite difference model to predict hydrogen distribution in a simulated part wall pipeline girth weld repair was demonstrated. The validity of the model prediction was assessed using slow bend tests where the deflection to failure was an indirect indicator of the local bulk hydrogen concentration at the critical site for delayed cracking. In the present investigation, the same hydrogen diffusion model has been used to predict the maximum time for delayed cracking in a simulated girth weld repair for two ambient temperatures, (20° and −10°C). These predictions are compared with the delayed cracking times in “constant deflection” tests performed at the selected ambient temperatures.

The results obtained showed that there was some scatter in the relationship between the experimentally applied deflections and the delay time to crack initiation. The delay time predicted by the model for the local hydrogen concentration to reach its maximum value at the crack initiation site, however, was a function of the ambient temperature and these agreed reasonably well with the maximum delay times to cracking observed in the experiments.
An Instrumented Field Corrosion Test Loop
Authors: Demoz Alebachew , Michaelian Kirk H. , Donini John , Papavinasam Sankara , Revie R. Winston
Published: October 2016

A multi-purpose instrumented loop in line with an oil producing well is described. The loop has several ports for coupons which were replaced periodically. Some of the coupons were used for electrochemical monitoring in addition to weight loss and visual inspection.

Weight loss, pit rate and all the electrochemical methods used gave corrosion rates that were dependent on the positions of the coupons inside the loop. The corrosion rate of the coupons increased from top to bottom. This order reflected the media and flow to which the coupons were exposed in a multi-phase producing well.
A New Rupture Prediction Model for Corroded Pipelines Under Combined Loadings
Authors: Wang Wei , Smith Marina Q. , Popelar Carl H. , Maple James A.
Published: October 2016

It is commonly believed that bending and other secondary loading will reduce the rupture pressure of a corroded pipe. This paper shows through theory, full-scale tests and finite element analysis (FEA) that this need not be the case in the field where displacement controlled bending and axial loading are induced by differential settlement and axial constraint. Based on this result, a new strain-based rupture prediction model is developed for buried corroded pipes subjected to internal pressure, lateral bending, thermal loading and residual stress. The selection of an appropriate “bulging factor,” the determination of a biaxial strain limit and the treatment of the heat affected zone (HAZ) are also discussed in the paper. The predicted rupture pressures agree well with the full-scale test results.
The Use of Reliability Based Limit State Methods in Uprating High Pressure Pipelines
Authors: Francis Andrew , Espiner Richard , Edwards Alan , Senior Gary
Published: October 2016

There is an increasing demand for operators of transmission pipelines to maximise the throughput of their pipeline systems. This can be achieved relatively easily with new pipelines, by using limit state design, new materials, novel fabrication techniques etc., Operators are also looking to maximise the throughput of existing transmission pipelines. Obviously, they are not able to make use of new materials etc., but limit state design concepts can be applied to show that a pipeline can be safely uprated to a higher design pressure.

The limit state of an engineering structure or component is defined as the mathematical relationship between the parameters associated with a particular failure mode at the onset of failure. To assess the impact on pipeline integrity and safety, a limit state approach incorporating probabilistic analysis has been developed. The approach addresses all credible failure modes and takes account of uncertainties in the relevant parameters for each mode.

The probabilistic approach takes the limit state approach a step further by describing the parameters as statistical distributions rather than single values. This allows failure probabilities to be computed which are a more meaningful measure of safety and allow areas of over conservatism (or under conservatism) to be identified. It is important to note that the approach is only as good as the limit states used and the data used to construct the distributions. Clearly uncertainties in both of these can exist and the absolute values of the computed probabilities must be viewed with caution. However, the strength of the approach lies in the relative values of the computed probabilities and previous ‘safe’ operation. If a system has a significant operational history with few or no failures and it can be shown that there is little change in the theoretical failure probability associated with a change in operating conditions, it can be inferred that few or no failures will occur in practice.

The paper describes the above approach in detail and outlines a study carried out to determine the effect on pipeline integrity of uprating three pipelines from a current maximum operating pressure of 70 bar to an uprated pressure of 85 bar, exceeding the current design criteria. By application of the limit state approach incorporating probabilistic analysis, it is shown that there would be an insignificant change in failure probability as a result of uprating to 85 bar, and hence that the integrity of the pipelines is unimpaired by uprating.
Pipeline Repair Based on Diagnostic Inspection – Investment Return
Authors: Pallaghy Barnabas , Bartos Andras
Published: October 2016

After the review and analysis of a 6000 km (3750 miles) pipeline system’s failure cases, we asked a theoretical question: what would this data show if we didn’t implement any in-line inspection or the consequential repairs and interventions? The amount of data considered is large enough to analyse how we could effect the undesirable changes.

The results clearly indicate that ILI and its associated interventions can measurably reduce the number of failures on a pipeline system. However, the extent of reduction is somewhat dependant on the vintage of the pipeline system.

If such interventions repair near critical defects only, the number of future failures decrease, but the trend remain unchanged. However, if the intervention is comprehensive, the failure trend will also decrease, indicatings, that in-line inspection of pipelines is a profitable investment.
In-Line Inspection Tools for Crack Detection in Gas and Liquid Pipelines
Authors: Willems H. H. , Barbian O. A. , Uzelac N. I.
Published: October 2016

The occurrence of stress corrosion cracking (SCC) has become a serious matter for many pipeline operators around the world. Advanced in-line inspection technology using nondestructive methods is considered the most promising approach to detect and size this kind of damage. Considerable progress has been achieved with the UltraScan CD (Crack Detection), a new generation of internal inspection device especially designed for the detection of axial crack-like defects in pipelines. Since its commercial introduction in October 1994, the crack detection tool has successfully inspected over 2,000 km of operating oil and gas pipelines. The inspection runs were followed by verification excavations at specific locations selected from the collected data. Comparison of the findings with corresponding verifications from excavations illustrate the sensitivity and reliability of the inspection concept and the ability of the tool to safely discriminate between injurious crack-like defects and different non-injurious reflectors such as e.g. inclusions. The performance has proved the tool to be a reliable internal inspection device for the detection and sizing of cracks (SCC, fatigue cracks and crack-like defects) in pipelines.
Deformation and Fracture Behaviors of Polyethylene Coatings on the Natural Gas Transmission Line With Ultraviolet Exposure
Authors: Lee Seong-Min , Shin Sung-Sik , Song Hong-Seok , Kho Young-Tai
Published: October 2016

The effect of carbon black, ultraviolet (UV) stabilizer and color pigment on the mechanical property of polyethylene (PE) has been investigated. The transition of fracture mode from ductile to brittle upon UV exposure is identified through microscopic examination of fracture surface. This transition is responsible for the degradation of mechanical properties.

The carbon black doped PE shows excellent UV resistance regardless of the presence of UV stabilizer. The mechanical properties of the PE remained unchanged even after 50-days UV exposure. The ductile fracture mode is also maintained in this case. The addition of red color pigment exhibited a very poor UV resistance.
Large Deformation Behavior of Pipe Bends Subjected to In-Plane Bending
Authors: Yoshizaki Koji , Ando Hirokazu , Oguchi Noritake
Published: October 2016

Ground liquefaction during earthquakes can produce a significant amount of lateral ground displacement. For buried gas pipelines, deformation and strain are likely to be concentrated on the pipe bends. Closing and opening in-plane bending experiments were conducted for various kinds of pipe bends until the measured strain exceeded 25% using pipe specimens of a diameter from 100 to 300 mm. The deformation behavior was different between the closing mode and the opening one. In the closing mode, an ovalization was observed in the central cross section of the bend, and internal pressure was maintained in all experiments. On the other hand, unique behavior was observed in the opening mode. When the pipe diameter was 300 mm (Do/t=43), local buckling was observed at the center of the bend. However, when Do/t was less than 32 (200 mm in diameter), the flexural rigidity of the bend became much higher than that of a straight pipe, and buckling and rupture were observed in the straight pipe. Finite element analyses were carried out using linear shell elements, and the validity of the numerical modeling technique over 25% of plastic strain was confirmed.
Strain-Based Pipeline Design Criteria Review
Authors: Dinovitzer Aaron S. , Smith Raymond J.
Published: October 2016

The new Canadian limit states pipeline design standard (CSA Z662-96, Appendix C - Limit States Design) incorporates deformation or strain-based design criteria to prevent pipe rupture and or buckling and limit ovality due to bending. These criteria are different and in some instances, much more conservative than those contained in the Canadian offshore pipeline design standard (chapter 11 of CSA Z662-96) and similar standards used in other countries. This study was completed to review the ovality, buckling (including wrinkling) and rupture criteria included in current Canadian pipeline design standards (CSA Z662-96) and define its basic differences with respect to other standards.

The deformation or strain based design criteria formulations in Z662 are compared with those contained in design standards, industry association recommendations and classification society rules from Norway, Britain, Germany, Australia and the USA to illustrate their differences and relative levels of conservatism. In addition, current and on-going research efforts were reviewed to identify the state-of-the-art in pipeline strain-based design, since this research could form the basis for future amendments to existing pipeline design standards.

Based on the findings of this review, recommended changes to the limit states pipeline design formulation are given to better reflect the strain-based (non-linear or post-yield) design and assessment approaches included in the Canadian offshore or foreign pipeline design approaches. In addition, an analytical basis for pipeline ovality and buckling design criteria are recommended.
Laboratory Tests and Numerical Modelling of Sleeper-Supported Line Pipe
Authors: DiBattista Jeffrey D. , Cheng J. J. Roger , Murray David W. , Zhou Z. Joe
Published: October 2016

This paper reports the results of experimental and numerical investigations into the behaviour of buried high-pressure piping supported by flat concrete footings known as ‘sleepers.’ In the study, a series of full-size line pipes are examined to determine their deformational behaviour when subjected to sleeper – pipe contact forces. Of particular concern are the distortion of the cross-section and the identification of potential buckling or wrinkling problems. Test results show that the pipes behave in a stable and ductile manner, but that the cross-sectional deformation can be considerable. A numerical model of sleeper-supported pipe, which includes non-linear material properties and accounts for large strains and deformations, is described. This model is found to represent sleeper – pipe interaction behaviour well. It is concluded that the analytical methods are sufficiently accurate to predict the behaviour of a pipe under the action of a known sleeper – pipe contact force. These analyses can be used to predict pipe behaviour directly and will be of assistance in the development of a simplified design technique.
Full Flow High Pressure Hot Taps: The New Technology and Why It’s Indispensable to Industry
Authors: McElligott John A. , Delanty Joe , Delanty Burke
Published: October 2016

The connection of a new pipeline lateral or loop to an existing high pressure pipeline system has always been fraught with high costs and the potential for major system impacts. Pipeline owners and operators have historically had to choose between a traditional cold connection with its high associated costs and a less expensive but more mysterious hot tap.

Although the cost savings of a hot tap have always been considerable, they were not always sufficient to justify the risk of complications during the branch weld or hot tap or during the subsequent operation of the system. Despite their extraordinary costs and throughput impacts, the perceived certainties of cold connections were often sufficient to justify their regular use.

The recent Kyoto Protocol on Climate Change has resulted in new commitments by the world’s governments to reduce greenhouse gas emissions. For the North American gas industry, these initiatives could result in voluntary compliance objectives, incentive based programs or legislated reforms — any of which will have significant impacts on current practices.

TransCanada PipeLines Limited (TransCanada) has successfully managed the risk/reward conundrum and completed more than 700 large diameter (NPS 12 to NPS 30) horizontal high pressure hot taps without incident since 1960. TCPL’s research and development work has enabled it to refine its procedures to the point where it can now complete branch welding and hot tapping work with minimal effects on throughput, negligible emissions and no system integrity impacts. For TransCanada, the direct advantages of a hot tap over a cold connection have resulted in the avoidance of gross revenue losses of $1 million or more per hot tap, no environmental emissions, seamless service and no impacts whatsoever to shippers. TransCanada PipeLines Services Ltd. (TPSL) has further streamlined the supporting field procedures and now provides a complete turn key service to industry.
Requirements of Pipeline Simulation: Accurately Modeling Transient Pipeline Operation
Authors: Hanks Kenneth H. , Stanley Galen T.
Published: October 2016

In an attempt simulate the hydraulic conditions actually exhibited in a pipeline, several simplifications have traditionally been made to reduce the computational requirements and complexity of the simulation models.

Recent advances in computer technology and solution techniques have allowed many of these simplifications to be removed. This paper discusses the benefit of the proper simulation of several of these areas. Transient vs. Steady state simulation, Two-phase vs. Single-phase simulation, Newtonian vs. Non-Newtonian fluid flow, Multi-component boiling and condensation in wet gas.

The effects of these features on leak detection, line pack, pressure loss, and inventory analysis are discussed, as well as the effects on pipeline design, operator training, and real time decision support.
Gas Demand Forecasting Based on Artificial Neural Network
Authors: Miura Kazuyoshi , Sato Ritsuo
Published: October 2016

Teikoku Oil Co. Ltd. (TOC) and NKK Corp. established a joint pilot project in 1994 in order to provide pipeline application and evaluation of NKK’s gas hydraulic simulation engine (GASTRAN) and to co-develop a Demand Forecasting Model (DFC). When the pilot project finished in March 1997, a commercial system, called Support Operation and Monitoring Application of Pipeline Simulator (SMAPS), was installed in TOC’s operation center.

The DFC, which is based on an artificial neural network architecture, has several advantages for sales forecasting especially as several dozen delivery points that have different sales patterns are connected to the pipeline network. The results from DFC can be easily used for scenarios in off-line simulation to predict future pipeline situations when it is attached to the SMAPS system. It automatically assists the pipeline operator by reducing his workload and evaluating operation plans.
The A.R.T. of Supervisory Control and Data Acquisition
Authors: Germain George L. , Clarke Terry W.
Published: October 2016

Understanding Business Process needs is critical to successful implementation of new Information Technology. Understanding Information Technology capabilities is critical to successful evolution of Business Processes.

Supervisory Control and Data Acquisition (SCADA) systems have been in the gas industry since the 1960’s. Earlier systems provided some data or information from the remotely controlled locations and a few key inter-connections. Now, sophisticated networked systems which contain layers of information detail from field devices and other computerized processes, feed simulators designed to study the process, use expert systems to advise on capability, and provide excellent data and information retention and retrieval tools.

The potential to automate business processes is more complete than ever before. Computers can now help to manage integrated business processes where important data and information is moved regularly from one business process to another under the watchful eye of validation steps, at specified frequencies, with all the necessary reporting to process workers about the health, and performance, of the business process, process links, and the computer system.

The business must understand the benefits and constraints which technology offers to a business process, and find ways to evolve the process with the new technology in hand. The IT manager must understand the business process needs in order to provide the appropriate technology to enable the business process with quick-change capability when change is indicated.

This paper explores some of the relationships between the business process, and the technology impacting the process, on the way to producing a flexible, enduring, and friendly SCADA network, ready to interact with other SCADA systems, other internal processes, and the external world.
Implementation of the Fast Track Express Pipeline SCADA Project
Authors: Sande Greg , Purich Terry
Published: October 2016

This paper describes implementation of a SCADA system on the new Express pipeline (1300 km, 24 inch, crude oil pipeline). The project was executed in a 12 month period — approximately half the time of a typical pipeline SCADA project of this magnitude. The project was completed on schedule (June, 1997) and under budget.
Pipeline Control: Merging SCADA and Gas Measurement
Authors: Clark Ian M. , Shaw Glenn
Published: October 2016

This paper discusses the merits of merging SCADA1 and gas measurement from a technical and economical perspective. Because traditional SCADA is largely limited to control room data used only for day to day operational purposes, the real-time metering data is not often utilized in the external revenue-generation business systems of the organization. In many cases, entirely separate measurement systems are utilized in isolation which often have few, if any, ties to the SCADA system which is capable of collecting pertinent measurement information.

Measurement data validation provides automatic data validation of flow measurement data upon retrieval from telemetered or non-telemetered data sources. Row measurement data can be supplied from field devices such as electronic flow computers or from other sources of flow measurement data such as manual operator entry, third party collection systems, chart integration sources, etc.

Flow measurement data undergoes a series of automated validation tests including single-run limit checking, meter run comparisons (at a given metering station) and historical validation tests (such as searching for frozen values). The outcome of these tests determines the data quality code assigned to each flow measurement reading (indicating the results of validation tests).

When combined with a real-time processing and data acquisition engine in a SCADA system that is capable of communicating with field devices via leased lines, VSAT, radio, dial-up, etc., many benefits can be realized.
Alarm Management Plan for Pipeline Facilities
Authors: Dvorkin Alex , Kemball Larry G. , Mah Dean B. , Perry Glen E.
Published: October 2016

The increasing size and complexity of natural gas transmission and distribution systems in North America are leading to higher dependence on automated, remote communication and monitoring of meter station, compression, and pipeline facilities. Along with implementing new technology comes the need to maximise operating cost efficiencies while continuing to deliver reliable transportation service. Managing alarm conditions at over 1100 receipt and delivery meter stations in an efficient and effective manner has become increasingly important for NOVA Gas Transmission Ltd. (NGTL) to satisfy customer requirements for finalising individual gas accounts on a daily basis. As a result, NGTL has developed a “Meter Station Alarm Management Plan”. This paper describes the process developed and implemented by NGTL in categorising and prioritising measurement alarms and providing the right response, along with the benefits to be achieved.
Identifying and Accounting for Environmental Costs
Authors: Jagger Doug , Korpach Dave
Published: October 2016

Protection of the environment has been and will continue to be a major issue facing the pipeline business around the world. Many of the decisions companies make relating to future investments and ongoing operations have environmental implications. These decisions can have significant cost implications that impact the bottom line of oil and gas transportation companies. Most companies do not track their environmental costs rigorously and thus, do not have a good understanding of the magnitude of these costs.

Recently, we have undertaken studies to define and identify the major environmental cost drivers in the industry. As part of these studies, we identified some potential measures of environmental performance and actually measured certain aspects of environmental performance in pipeline companies.

This paper will provide insights into the major environmental cost drivers in the industry and will define these cost drivers. It will provide some ideas on “what to measure” relating to environmental costs.

Implementing an environmental cost management system is not a trivial task. It is difficult to assess how much of the cost associated with a certain investment is related to the environment. This can only be determined on a project by project basis and will also be unique from company to company. Although there is no “cookbook” approach to implementing this system, this paper will provide some guidance for implementing such a system.
Hydrostatic Pressure Testing Program for a Liquid Petroleum Products Pipeline
Authors: Hadden Robert V. , De Leenheer Kevin J.
Published: October 2016

As part of its Integrity Management Program, Trans Mountain Pipe Line hydrostatically tests sections of its pipeline system with water transported to test sites through the pipeline. After completion of the testing, the water continues through the pipeline to a water treatment facility where it is treated and discharged to the municipal sewer system.

Hydrostatic testing of an operating pipeline, although simple in concept, is a major undertaking. This paper will outline the technical aspects of Trans Mountain’s hydrostatic testing program including: test water transportation, environmental constraints, coordination of test activities and water treatment.