bluuebunny/crossref_metadata_2025 huggingface dataset:
L00200 Wear in Pipeline Engines and Compressors - Methods of Measurement
Authors: Kniebes D.V.
Published: August 2023

A two-year study of the wear history of 84 pipeline compressor engines in relation to the concentrations of metals in the lubricating oils from these engines has demonstrated the feasibility of using lubricating oil analyses as a means of detecting increased rate of wear of engine components prior to their failure in service. Inexpensive emission spectrographic analyses were used to determine the metal content of the lubricating oil samples in the parts per million ranges.

The non-detergent lubricating oils from most of the engines, which operated normally during the study contained low concentrations of, wear metals. It was, therefore, possible to indicate tentative upper limits for metal concentrations in non-detergent oils from normally operating engines, However, these limits are applicable only to engines in which oil is well filtered or sufficient new makeup oil is added to keep the wear metal concentrations down. Other exceptions were found where metal-containing lubricants and sealing compounds entered the oil in trace amounts. Several instances of abnormal ring and bearing wear, which occurred during the test program, were indicated by an increase in iron, lead or tin concentrations in the engine lubricating oil up to several months in advance of the necessary part replacement. Although the highest sensitivity to wear rate changes is obtained with clean, non-detergent oils, the method is still useful with detergent oils which tend to retain larger amounts of wear metals in suspension.

The information obtained in this study will permit individual pipeline companies to evaluate the merits of lubricating oil analysis as a preventive maintenance tool for their own operations, and will furnish a basic understanding of the methods used to properly interpret the analytical data.
L51419 Assessing the Cathodic Protection Levels of Well Casings
Authors: Kiefner  , Eiber
Published: August 2023

This report is oriented towards providing a tutorial explanation of casing response to applied protection current based on computer-modeled examples. This presentation will allow the reader to obtain an insight into the parameters, which affect casing behavior when a storage field is energized with cathodic protection currents.

The principal objectives of this research program were: (1) to develop a method for predicting the down-hole distribution of protection current in a well casing; (2) to identify surface measurements which could be used to assess protection levels on the casing and (3) to identify the principal interference mechanisms in a storage field and develop a means of determining their effects.
L51961 Coating Compatibility at Thermite Welds and Keyhole Excavations
Authors: Ruschau
Published: August 2023

Patching and repairing high performance pipeline coatings requires a high performance repair material to ensure the integrity of the coating system. The application conditions are not optimized as they are during plant applications, so it is imperative that repair coatings applied to mainline coatings will adhere to all coated surfaces so that resources can be focused on optimizing application methods. Compatibility of repair coatings applied to thermite weld components may be inadequate for optimum field performance. When combined with the limiting factors of keyhole excavations it is important to use coatings which are not only compatible with the thermite welds but also are suitable for the keyhole application procedure.

A series of 14 pipeline repair coatings were evaluated for their compatibility with the components of a thermite weld. Chemical compatibility was determined in terms of adhesion with the thermite weld individual components: polyethylene wire insulation, polyvinylchloride wire insulation, copper wire, steel, and copper/aluminum thermite alloy. The same coatings were evaluated for their suitability for application by keyhole excavation procedures. A keyhole excavation was simulated using a scaffold over filled soil boxes (dry soil) containing buried pipe sections, and each of the repair coatings was applied by a commercial keyhole excavation company. The ease of application and general suitability was rated. After backfilling and aging for six months, the samples were removed from the soil boxes and the coatings evaluated.
L52299 Revised Analysis of Orifice Meter Expansion Factor Data
Authors: George
Published: August 2023

Orifice meter expansion factor data collected at Southwest Research Institute (SwRI) between 2003 and 2005 have been reviewed to assess the effect of an assumption made during data reduction. In accordance with the North American orifice meter standard, AGA Report No. 3, Part 1, the data were originally analyzed using a constant value of the isentropic exponent, k = 1.3. By comparison, the expansion factor equation adopted by ISO employs the real isentropic exponent, K, which is a function of pressure, temperature, and gas composition. The SwRI orifice meter expansion factor data have been re-reduced, using values of the real isentropic exponent from archived test data in place of the ideal gas value of k = 1.3. The original expansion factor data were obtained in such a way that the expansion factor values themselves were unaffected by the value of the isentropic exponent. However, the use of k = 1.3 influenced the values of the acoustic ratio, the independent variable used with the AGA and ISO equations to compute values of the expansion factor in measurement applications. The use of the ideal isentropic exponent in the original SwRI data, instead of real values of the isentropic exponent, was found to have caused an average shift in the acoustic ratio.
L51571 Pipe-Soil Interaction Tests on Sand and Soft Clay
Authors: Deaton  , Frost
Published: August 2023

This project was performed to establish a basis for developing pipe-soil interaction models suitable for PRCI's pipeline design program: "PIPEDYN".

Full-scale pipe-soil tests on loose and dense sand and soft clay were performed at the Norwegian Hydrotechnical Laboratory, affiliated with SINTEF. The program tested soil resistance to lateral motions of full-scale (0.5 m and 1.0 m OD) pipe sections on loose and dense sand and soft clay. A test rig was used with a soil flume 12.5 m long, 1.8 m wide, and 0.6 m high, and containing 13.5 m3 of sand or soft clay. Three control signals were applied to the test pipes: simple breakout, regular oscillatory tests and breakout, and random tests with force time histories. The parameters considered were pipe diameter, pipe weight, pipe oscillations, and oscillation amplitude. A total of 110 tests were performed in 25 test flumes (13 preliminary and 12 main) on loose sand, three test flumes on dense sand and ten test flumes on soft clay.

Forty-five preliminary and 32 main tests were performed in 25 loose sand flume preparations, whereas 8 main tests were performed in 3 dense sand flumes and 25 main tests in 10 soft clay flumes, for a grand total of 110 pipe-soil tests in 38 soil flumes. Special plate and cone penetration tests were also performed as part of the soil bed tests. Based on the results of the tests, pipe penetration appears to be the most important factor influencing lateral soil resistance. Also, the soil resistance in loose sand was generally higher than in dense sand due to larger pipe penetration and an accordingly higher lateral earth pressure.
L51587 Field Techniques to Determine Electrical Shorts Between Carrier Pipe and Casing Pipe
Authors: Han  , Burns
Published: August 2023

Corrosion protection of pipelines inside casings recently has received increasing attention. Although, historically, the safety record of operating pipelines within casings has been excellent, recent experience of the pipeline industry has suggested that potential problems may exist and improved or new field techniques for monitoring the effectiveness of corrosion control practices need to be developed specifically for the pipeline within casings. Furthermore, the mechanism or the root cause of corrosion of pipelines inside casings needs to be better understood.

The objectives of the research have been to develop a reliable field technique, based upon the AC-impedance technique, to determine whether or not a carrier pipe is electrically (metallically) shorted to a casing pipe, and to develop a prototype instrument for field use. During 1987, Task 1 "Development of a Field Technique to Determine Electrical Shorts" was performed. Major subtasks performed in Task 1 were a review of the currently available field techniques for electrical short detection
L51924 Evaluation of Welding Consumables and Processes for X100 Steel
Authors: Johnson
Published: August 2023

The primary objective of this study was to evaluate the mechanical properties of weld metals deposited using a number of commercially available welding consumables and welding processes. The secondary objectives of this work included characterizing weld metal microstructure, assessing hydrogen-assisted cracking susceptibility of the weld metal and X100 base metal, and solidification cracking susceptibility of selected welding consumables.
L51843 Alternative Processes for Welding onto In-Service Pipelines
Authors: Fowler
Published: August 2023

The objective of this program was to evaluate alternatives to commonly used processes and practices for welding onto in-service pipelines for hot tapping and repair. The use of alternative processes and practices has the potential to increase deposition rates and significantly reduce the cost of welding onto in-service pipelines and may expand the range of materials and situations for which welding at full-pressure and full-flow can be applied.
L51740 Evaluation of the Structural Integrity of Cold Field-Bent Pipe
Authors: Olsen
Published: August 2023

During recent pipeline construction seasons, there have been reported difficulties in cold field bending different joints of line pipe produced by the same manufacturer during a particular production run. These difficulties were typically manifested as an inability to achieve bends of one to one-and-a-half degrees per diameter in the pipe without forming ripples. Some of these problems could be traced to poor bending practices, i.e., inappropriate bending machine set-up and operator inexperience. However, it was observed that even with proper machine set-up and experienced operators, some "bad pipe" exists that could not be bent as far as desired without introducing ripples. The objective of this program was to develop an acceptance criterion for an allowable ripple in a gas-transmission pipeline as a result of a cold field bend. Previous acceptance or rejection criteria for ripples in cold field bent pipe were quite subjective. The purpose of this study was to define quantitative limits for acceptable ripple heights that will not compromise the integrity of the pipe during its expected life. In a program discussed at the 9th PRCI/EPRG meeting, the work performed during a joint Australian Pipeline Industry Association/Line Pipe Research Supervisory Committee effort on the mechanics of cold field bending was presented. Based on theoretical and experimental studies, it was found that modern, high-strength, high D/t pipe forms ripples at very low bend angles during cold field bending. Although there was some circumstantial evidence that some amount of rippling can be tolerated in a pipe, there had been no systematic effort to quantify the influence that the ripples have on the long-term integrity of pipe.
L51754 Field Application of Electronic Gas Admission with Cylinder Pressure Feedback for LB Engines
Authors: Fowler
Published: August 2023

�The purpose of this project was to evaluate the performance of electronic fuel gas admission valves and effects of continuous automatic cylinder balancing of large bore natural gas engines under actual field conditions. These goals have already been met under laboratory conditions at the Colorado State University Engines and Energy Conversion Laboratory in Fort Collins. The specific project objectives were to:1. Extend the feasibility of electronic fuel gas admission valves where gas valve timing and duration are varied to optimize fuel control and charge mixing from the laboratory environment to actual field applications. 2. Extend the feasibility of closed loop control using in-cylinder pressure sensors to achieve continuous, automatic power cylinder balancing from the laboratory environment to actual field applications. 3. Repeat the benefits of automatic continuous cylinder balancing shown in the laboratory testing under actual field conditions (i.e. fuel savings, improved cylinder misfire rates, improved emissions levels).

In order to accomplish these objectives, the Woodward Governor Company AutoBalance TM 5000 control system was installed and tested at four host sites. Although the specific test plan differed slightly for the four host sites, the focus of the test program was consistent. The primary objective was to evaluate the effects of engine balance and the performance of the control system by testing a matrix of varying engine loads and speeds. Load and speed are the two primary control parameters affecting engine balance. Other tests were conducted to determine the effects of the electronic gas admission valve (EGAV) configuration (i.e. start of admission, end of admission, and duration).
L52335 Weld Strength Mismatch Requirements
Authors: Wang  , Wu  , Liu
Published: August 2023

To establish rational approaches to weld strength requirements. Such requirements are correlated to the expected construction and service conditions throughout the pipeline's service life. No single strength requirement is good for all conditions. �Over-specifying"� the strength requirement may not be necessary and can be counterproductive. On the other hand, �under-specifying"� the strength requirement may lead to inadequate safety and integrity.

This work includes:

Initial feasibility study of weld strength requirement for a particular pipe grade and application,
Evaluation of the impact of weld strength on weld performance measures, such as the tensile strain capacity of the girth welds,
Playing �what-if"� scenarios and developing trade-off strategies among various parameters governing the girth weld integrity for certain performance requirement. For instance high degree of overmatching may be used to compensate for large high-low misalignment.
L51702 Precision Gas Pipeline Location-A Technology Study
Authors: Meloy John D.
Published: August 2023

A review of currently used pipe-locating techniques and technologies shows a universally conservative approach to system design. Tested and proven sensors and data processors have been integrated into systems that optimize performance specifically for the pipeline-location problem. Although these systems perform well, they could be improved and augmented (that is, performance could be enhanced) by incorporating a broader sensor mix. Emerging technologies also hold promise for upgrading performance by improving, rather than changing the basic sensors. This study was undertaken to survey and evaluate the technology available to determine accurately the position of submerged or buried gas transmission pipelines, and to assess the applicability of some of the emerging technologies. The objectives are to increase accuracy and reliability while reducing the cost of surveys. This report is organized to provide an overview of the elements applicable to the problem of pipe detection, identification, and location. These elements include basic sensors and pipe-location systems made up of sensors, computers, peripherals, and data links. The report includes a qualitative comparison of both sensors and systems using a number of performance criteria. A brief description of relevant technologies that have been developed for uses other than pipeline location, as well as new and emerging technologies, is also included.
L51756 State of the Art Intelligent Control for Large Engines
Authors: Willson
Published: August 2023

Computers have become a vital part of the control of pipeline compressors and compressor stations. For many tasks, computers have helped to improve accuracy, reliability, and safety, and have reduced operating costs. Computers excel at repetitive, precise tasks that humans perform poorly - calculation, measurement, statistical analysis, control, etc. Computers are used to perform these type of precise tasks at compressor stations: engine / turbine speed control, ignition control, horsepower estimation, or control of complicated sequences of events during startup and/or shutdown. For other tasks, however, computers perform very poorly at tasks that humans find to be trivial. A discussion of the differences in the way humans and computer process information is crucial to an understanding of the field of artificial intelligence.

In this project, several artificial intelligence/ intelligent control systems were examined: heuristic search techniques, adaptive control, expert systems, fuzzy logic, neural networks, and genetic algorithms. Of these, neural networks showed the most potential for use on large bore engines because of their ability to recognize patterns in incomplete, noisy data. Two sets of experimental tests were conducted to test the predictive capabilities of neural networks. The first involved predicting the ignition timing from combustion pressure histories; the best networks responded within a specified tolerance level 90% to 98.8% of the time. In the second experiment, neural networks were used to predict NOx, A/F ratio, and fuel consumption. NOx prediction accuracy was 91.4%, A/F ratio accuracy was 82.9%, and fuel consumption accuracy was 52.9%. This report documents the assessment of the state of the art of artificial intelligence for application to the monitoring and control of large-bore natural gas engines.
PR-186-073503-R02 Requirements for Existing Pipeline Tank and Terminal Systems to Transport Ethanol
Authors: Beavers John
Published: August 2023

The potential exists for stress corrosion cracking (SCC) of carbon steel pipelines transporting fuel grade ethanol (FGE) and FGE- gasoline blends. The objectives of SCC 4-4 were to: 1. Develop data necessary to make engineering assessments of the feasibility of transporting FGE and FGE blends in existing pipelines, 2. Identify ethanol blends that can be transported in existing pipelines without significant modification of the system and operations (Case 1); blends that require significant modifications (Case 2) and blends that cannot be transported in existing pipelines, but could be moved in specially designed systems (Case 3), and 3. Characterize the time to initiation of SCC in a range of potent ethanol environments and identify safe operating and or batching practices that prevent the initiation and growth of SCC. The results of the research (Phase 1 and Phase 2) demonstrated that: 1. Pipelines made of common line pipe steels (e.g., Grade B and X-42 to X-60) are likely to be susceptible to ethanol SCC and any differences in susceptibility are probably not relevant from an integrity perspective. 2. While differences in susceptibility were noted for some weld types, in general, the base metal, heat affected zone, and weld metal were all susceptible to SCC in SFGE. 3. For sharp cracks, SCC initiation times are short once the line pipe steel is exposed to FGE or FGE blends capable of promoting SCC. 4. Once cracks initiate, crack growth rates are high in comparison with other forms of pipeline SCC. 5. Batching does not appear to be a viable method for SCC mitigation. 6. The only blends that can be safely transported in existing pipelines without significant modification of the system or operations (Case 1) are those containing less than 15% ethanol. 7. All other blends require significant modifications of the system or operations (Case 2), or specially designed systems (Case 3). 8. Case 2 could include deaeration of the SFGE, or the addition of inhibitors. 9. Case 3 is the subject of ongoing research (SCC 4-5).
L52314 Pipeline Defect Assessment - A Review and Comparison of Commonly Used Methods
Authors: Kiefner  , Leewis
Published: August 2023

There is a need in the industry in assessing the severity of a particular anomaly (dent, gouge, corrosion pit, etc.) in a pipe as to whether or not repair or removal is warranted. Along with the determination of repair there is also a need for prioritizing in-line-inspection (ILI) data, and for making remaining-life assessments of said pipe.

This document catalogs analysis methods and computational tools for addressing defects and damage discovered on in-service pipelines. It includes example calculations where closed-form algorithms are available in the public domain. It lists and describes solution techniques not available in the public domain, and it provides information so that users can either acquire the relevant software or pursue assistance regarding a particular defect assessment technique.
L19710 A System for Detecting and Measuring Interference
Authors: Hayes
Published: August 2023

The objective of this project was to develop a prototype instrumentation system and analysis procedures by which the various components of electrical current existing on a subsurface structure may be identified as to magnitude and source of origin. The resulting prototype equipment and data analysis procedure are called the Interference Monitoring System (IMS). This technique is based on the principle that each distinct source of current in the earth will generally induce current in a structure in a characteristic manner that is unique to the source.The approach was applied to a gas pipeline in western Oregon. Instrumentation recording equipment and analysis procedures were developed and used to effectively demonstrate the capability of the system.
L00038 Variations in Electrolytic-Cell Conditions in Hard-Spot Regions of Line Pipe
Authors: Groeneveld  , Fessler
Published: August 2023

Hydrogen-stress cracking (HSC) has occurred in natural gas transmission pipelines only in localized hard regions in the pipe wall (hard spots) or in hard weld zones. A specific factor that results in the initiation of HSCs in some hard spots is the possible variation in localized electrolytic cell conditions that could exist because of variations in microstructure, hardness, and residual stress in those regions. This paper presents the results of a study of these variations. The first part of the study evaluates whether local variations in pipe-to-soil potential existed in hard spot regions subjected to an imposed potential. The second part involves monitoring the current flow and hydrogen entry into high-strength, line-pipe steels as a function of the imposed half-cell potential.It was concluded that the variation in potential was greater for a section of pipe removed from a hard spot than it was for a section that did not contain a hard spot. No correlation was found between the hardness variations and the half-cell potential variations. Consequently, factors such as surface condition of the pipe or variations in the residual stresses may influence the value of the half-cell potential and the amount of variation in the half-cell potential in hard-spot regions. The variations in half-cell potential that can occur in hard spots and the variations in residual stress that have been measured in hard spots do aid in explaining why the cracks that occur in hard spots frequently initiate at locations other than the hardest region.
L20020 Steady State Flow Computation Manual for Natural Gas Transmission Lines
Authors: Ellington  , Staats
Published: August 2023

The goals of this project were to continue to evaluate available knowledge on the flow behavior of gas in transmission systems and develop a simple, flexible equation form for use in calculations, without sacrificing accuracy. This manual presents definitions and instructions for determining the type of flow (fully turbulent or partially turbulent) and instructions for flow calculations for both flow types. The procedures and recommendations in this manual are limited to calculations on gas transmission and gathering lines in which entrance losses and kinetic energy changes are negligible. The calculation procedures relate to steady state flow of either the fully turbulent or partially turbulent types and apply only to the solution of conventional pipeline flow problems.
L51480 Investigation of Pressure Losses in Compressor Station Yard Pipework
Authors: Sparks
Published: August 2023

Details an investigation of the pressure losses associated with a variety of fittings based upon readings collected at four actual pipeline stations involving both reciprocal and centrifugal compressors. Evaluation of existing pressure loss coefficients where available, and procedures for calculating pressure drops as necessary are presented.
L51416 Hyperbaric Shielded Metal Arc Welding - Cold Cracking
Authors: Bailey  , Read
Published: August 2023

Cranfield Institute of TechnologyResults incorporated in this report show that SMAW may be successfully applied to underwater repair and maintenance tasks. However, process tolerance is tight in view of limitations on acceptable pre-heat levels usable in confined sub-sea habitats. It is therefore suggested that further investigations with SMAW should be conducted to explore ways in which the process can be more safely applied. It is also recommended that suitable forms of very low hydrogen processes are examined with a view to hyperbaric operations.
L51527a State-of-the-Art Report on Multiphase Methods Vol 1
Authors: Rothe
Published: August 2023

Three volumes. Report based on a multi-year effort to develop a Two-Phase Flow Design Manual. Intended to assess the current application of multiphase flow hydraulic methods to system design. Volumes are as follows: Vol. 1, Guide to Quick Calculations; Vol. 2, Guide to Computerized Calculations; and Vol. 3, Theoretical Supplement.
L51511 Deactivating Power Cylinders under Reduced Load on Two-Cycle Engines
Authors: Smalley  , Vinyard  , Evans
Published: August 2023

Investigates potential and procedures for selective deactivation of one or more power cylinders in two-cycle engines under reduced load to effect fuel savings while avoiding possible engine derangement. The objectives were to identify any major problems with cylinder deactivation, to quantify likely benefits, to determine potential increases in load or stress, and to generate guidelines from the project results. This study showed that economic benefits are possible with the careful use of cylinder deactivation; however, several operational problems were encountered, such as spark plug fouling, oil pumping, increased noise due to a mismatched muffler cutoff frequency, and increased wear in the deactivated cylinders.
PR-015-123741-R01 Alternatives to Current Leak Detection Approaches for Hydrotesting
Authors: Siebenaler  , Walter  , Brysch
Published: August 2023

Hydrotesting is a key component of pipeline integrity management. This testing is one of the primary methods used by pipeline operators during the commissioning process of a line segment. Hydrotesting is also used to validate the maximum allowable operating pressure (MAOP) of existing pipelines. One element of this test is to identify water leaks in a timely fashion so that they can be fixed before the pipeline is returned to service. The most commonly-cited method for leak detection during hydrotesting is the use of sulfur hexafluoride (SF6) as a tracer compound. This tracer is a powerful greenhouse gas and, thus, a project was initiated to determine if alternate means of leak detection are available for this application. Based on the concerns of pipeline operators, PRCI initiated a project to identify and explore possible alternatives to the use of SF6. These alternatives could be in the form of an alternative tracer compound or through the use of a different leak detection technology. The objectives of the project were to identify possible alternate technologies and then to choose two or three for further exploration after a tradeoff study was performed to grade each technology against a set of requirements. This document provides final reporting for this project.
L51538a Guidelines for Subsea PL Repair and Tie-In Systems Vol 1
Authors: Unknown Author
Published: August 2023

Gives a detailed overview of existing and development maintenance and repair systems. Guidelines identify economies, capabilities and limits of repair systems for a wide-range of water depths, pipeline diameters, and sea (local) conditions; damage assessment included.
L51567 Influence of Filler Wire Carbon and Residual Element Content on the Mechanical Properties
Authors: Gray
Published: August 2023

This study was conducted to determine the interactive roles of carbon, oxygen, and nitrogen and residual elements such as titanium, chromium, copper, sulfur, phosphorous, aluminum, tin, antimony, and arsenic on weld metal mechanical properties in pipeline steels. Eleven seamless, flux-core electrodes were fabricated with varying compositions and deposited in girth welds in a 24-inch diameter, API 5LX-65 pipe using the gas-metal-arc-weld (GMAW) process. The results of Charpy V-notch and crack-tip opening displacement tests indicate that desirable toughness properties may require the addition of alloying elements (e.g., nickel) that promote the formation of acicular-ferrite microstructures. In addition, small variations in sulfur content were shown to cause significant variability in notch toughness.
PR-015-14603-R01 Turbine and Coriolis Meter Diagnostics with Entrained Liquids
Authors: Hawley  , Thorson
Published: August 2023

This research evaluated the performance of select Coriolis and turbine meters in natural gas flows before, during, and after a wet gas flow condition. Low viscosity oil was used as the liquid phase for the testing. On-board diagnostics from the Coriolis meters and auxiliary diagnostics for the turbine meters were used to determine if the presence and loading amount of the liquid could be determined.
L51642 Field Nondestructive Examination of ERW Pipe Seams
Authors: Bruce
Published: August 2023

Electric resistance welded (ERW) pipe has been used in the natural gas transmission industry for many years. The Department of Transportation (DOT) has recently expressed interest in the integrity of the weld seam in pipelines made from ERW pipe that was manufactured prior to 1970. Specifically, the DOT has requested that natural gas transmission and hazardous liquid pipeline operators determine whether or not their pipelines that meet this description require hydrostatic proof testing. The initial concern from the DOT was for seam weld selective corrosion, although reference has since been made to growth of manufacturing discontinuities in the ERW seam. Early ERW pipe was manufactured using either direct current or low-frequency alternating current, processes that were prone to producing incomplete fusion discontinuities. These discontinuities (also referred to as cold welds, penetrators, etc.), if present in a pipeline, can grow under normal service or under upset operating conditions resulting in leaks or ruptures. There exists a need for a method that a pipeline operator could use to demonstrate the integrity of pipelines that were made from this older ERW pipe other than hydrostatic testing, which is expensive and potentially harmful to pipeline integrity. The use of a nondestructive-examination (NDE) technique would enable an operator to sample the integrity of a suspect pipeline during other routine in-service maintenance operations without the need for hydrostatic testing.

The detection of incomplete fusion discontinuities is difficult if not impossible with conventional NDE techniques. The intimate mechanical contact between compressed surfaces causes a small amount of reflection and a large amount of transmission of ultrasonic signals. Recently however, several ultrasonic techniques have been introduced to study these types of discontinuities in resistance spot welds and inertia friction welds. These new techniques are based on ultrasonic spectroscopy, that is, the frequency dependence of the various ultrasonic interfacial parameters. These parameters include reflection and transmission coefficients and the frequency dependence of ultrasonic volumetric parameters (e.g., velocity and attenuation).
L51705 Cyclic Pressure Fatigue Life of Pipelines with Plain Dents Dents with Gouges and Dents with Welds
Authors: Wilkowski  , Maxey  , Eiber
Published: August 2023

Research has been conducted to study the effects of dents, gouges, and weld seams on pipelines under cyclic internal pressure loading. The work associated with this project has involved both experimental and finite element analysis on pipes with D/t ratios from 19 to 94 experimentally and 18 to 100 theoretically. In support of this research, operators were surveyed regarding the expected dent shapes and failures that had occurred as a result of pipeline dents. The experimental portion of the work involved pipes (one 24" and several 12" NPS pipes) with controlled dents which were combined with welds and gouges. All specimens were subjected to cyclic internal pressures to study behavior in terms of fatigue. Elastic and plastic finite element analyses were conducted to determine stress concentration factors due to dents so that a fatigue analysis could be performed.

Both the experimental and theoretical research indicated that plain smooth dents with depths less than 5% of the diameter should not be a problem (regardless of the D/t ratio) unless the cyclic pressure service is very severe. Experimental results demonstrated that gouge depth has a significant impact on fatigue life. Unground gouges whose depth is more than 10% of the wall cannot be counted on to have any fatigue life. The process of grinding out the gouges was found to be an excellent method of repair, even when considering gouge depths as large as 15% of the pipe wall thickness. The position of the dents relative to the longitudinal welds was not found to be a determining factor when considering reduction in fatigue life; however, dents which were placed on girth welds had considerably shorter lives than dents which were off of these welds. Classification of the gouge depths in terms of wall thickness (d/t) was found to be the most effective means for categorizing these types of defects. An analytical procedure was developed for predicting fatigue life of a pipe with plain dents subjected to cyclic pressure loading. These results were compared to experimentally obtained values.
L52245 Improvements to the Two Curve Ductile Fracture Model - Soil-Elastic and Plastic Contributions
Authors: Rudland
Published: August 2023

The most commonly used fracture analyses procedure for the prediction of minimum arrest toughness and fracture speed for axially running cracks in line pipe materials for natural gas transmission pipeline applications is the Battelle Two-Curve approach. This analysis procedure incorporates the gas-decompression behavior with the fracture toughness of the pipe material to predict the minimum Charpy energy required for crack arrest. For this model, the effect of backfill on the propagating crack fracture speeds is lumped into one empirically based �backfill coefficient,� which does not distinguish different soil types or strengths. This report provides a better understanding of soil behavior and its affect on the fracture speed of running axial flaws in buried line pipe materials. The results from this program are combined with other full-scale experimental data in developing a modification to the treatment of backfill in the Battelle Two-Curve approach for calculating minimum arrest toughness. This first major improvement to the Battelle Two-Curve approach is incorporated into a computer code called PIPE-DFRAC.
L51641 Evaluate NDT Methods for Welds in Service
Authors: Swankie  , Martin  , Andrews
Published: August 2023

The inspection of welds made onto in-service pipelines, which are made primarily for attaching branch connections and repair sleeves, has been the subject of much concern in recent years. The difficulties associated with the inspection of these welds have long been recognized and, historically, the amount of inspection given to such welds has been small. The inspection of welds joining various appurtenances to pipelines is hampered for a number of reasons. The joint geometries can vary considerably, but none of them are particularly suited to detailed inspection. Surface techniques, such as magnetic particle and liquid-penetrant testing, rely on the flaws being at or near the surface, and this is not necessarily the case with the welds of concern. Radiography is difficult since it is not possible to place a radiation source within the pipeline. Ultrasonic inspection is, therefore, the only option if a full volumetric inspection is required. This is made difficult by the inherent complex geometries, and limited access to many of the welds. Welding on pipelines containing flowing, pressurized products results in very rapid cooling of the weld metal and heat-affected-zone regions, significantly increasing the risk of cracking. The use of high hydrogen consumables (specifically EXX10 SMAW electrodes) adds considerably to the risk The probability of discontinuities forming during welding on in-service pipelines is therefore considerably greater than for pipelines that do not contain flowing products.

The goal of the present work was to evaluate existing techniques, and to develop and verify improved methodsfor inspection of such welds. In the first phase of this program, welded assemblies that contain realistic examples of discontinuities that occur in practice were produced In the second phase, the reliability of existing nondestructive testing methods were evaluated along with the reliability of novel nondestructive testing systems. The overall objectives of these first two phases were to evaluate the accuracy and reliability of nondestructive testing methods currently applied to welds made onto in-service pipelines, and to assess the improvement possible with methods that are more advanced, but so far have had limited application to these welds. The objective for the Phase III continuation of this project is to demonstrate the accuracy and reliability of nondestructive testing methods using procedures that are optimized based on the knowledge acquired in the first two phases.
L52075 Analysis of Pipeline Data Standards
Authors: Bever
Published: August 2023

Three standards were evaluated to assess the the potential for a unified standard: ISPDM (Industry Standard Pipeline Data Management), ISAT (Integrated Spatial Analysis Techniques), and PODS (Pipeline Open Data Standard). The scope of the analysis included: establishing the basic information modeled in each standard, information modeling techniques employed in each standard, exclusive/overlapping information in each standard, and evaluation of a potential integrated standard. This analysis has been performed using information publicly available from each standard owner.
L51483 Evaluation of EPA Method 20 Ambient Correction Procedure
Authors: Klausmeier
Published: August 2023

Addresses the effects of the current EPA Method 20 correction factors on predicted NOx levels vs. actual observed NOx emissions based upon data from some 800 engine field test data sets. The report demonstrates that correction procedure to the 85 degrees F / 75 grains of water per pound of dry air standard introduces considerable over-prediction and presents a case for the elimination of the procedure or at a minimum a modification to permit regional correction factors. The data sets are displayed in Appendix of some 200 p.
L52284 Upheaval Buckling Limit State Function for Onshore Gas Pipelines
Authors: Zhou
Published: August 2023

For buried pipelines a well established problem has been that of upheaval buckling. This occurs because the fluid is usually pumped through the pipes at elevated temperatures causing the pipeline to experience thermal expansion which, if restrained, leads to an increase in the axial stress in the pipeline possibly resulting in a buckling failure. A secondary phenomenon that has also been identified, particularly in loose sands and silts, involves floatation of pipelines through the backfill material, usually shortly after burial.

The upheaval buckling limit state function developed in this project employs the critical upheaval buckling force and applied compressive force due to temperature and pressure. It applies to pipe sections containing a hill-crest type of imperfection over which the pipeline is routed using a series of cold formed bends. The critical buckling force is calculated using an empirical equation developed by Boreas based on the results of parametric finite element analyses (FEA) on 252 design cases. The input parameters for the empirical equation are pipe diameter, diameter-over-wall-thickness (D/t) ratio, grade, pressure, soil download and imperfection angle. The development of the equation is described in a technical report prepared by Boreas.
L51404 Evaluation of Shielded Ignition Systems for Gas-fired Stationary Engines
Authors: Munsch
Published: August 2023

This report traces the historic application of shielding to the ignition system high tension components on stationary reciprocating engines and presents the operating experience data available as a basis for comparing shielded and conventional (open) ignition systems. The early and predominately unsuccessful experience of operating companies going back to twenty or more years ago are described as are the more recent experiences with newer systems. Several attempts were made to trace the development of regulations which mandate shielded ignition systems and to document the need for such regulations. No such references were found in the published material examined.
L51573d Pipe Connection Methods and Effects on Deepwater Construction D
Authors: Litzelfelner
Published: August 2023

A study to review and evaluate the various mechanical pipeline connectors currently available for J-curve pipelay methods offshore. The connectors were compared by listing the advantages and disadvantages of each. A test program to evaluate connectors was developed.
PR-186-09204-R01 Determining the Effects of Ethanol on Pump Station Facilities
Authors: Beavers John , Quickel Gregory
Published: August 2023

The first task in Phase 1 of this project involved sending out an industry survey regarding materials in pump stations. This task was performed to determine what components are important from a facilities point of view and what materials are used in these components. The information from the survey was organized into a table that is attached as an appendix to this report. Additionally, manufacturers of the components were contacted in order to determine the materials present in the components in the pump stations. The requests for bill of materials or materials for specific part numbers were performed by email and/or phone calls. The second task involved performing a literature search. The survey focused on data from the literature on the ethanol exposure effects of materials involved in various pump station components. The open literature, as well as company reports, was considered. Previous literature surveys conducted for PRCI SCC 4-1 and 4-4, and API, were utilized. The open literature search was performed using two search engines; Engineering Village and Science Direct. The keywords in the search included ethanol, corrosion, failure, various non-ferrous metals, stainless steels, and elastomers/plastics.
PR-004-103600-R01 Inspection Report for the GTI Pipeline Coating Test Facility Project - Phase I
Authors: O'Brien
Published: August 2023

This report describes the efforts to coat piping used at the GTI Coating Test Facility. In total 53 different coating systems were installed as part of this project. The goal of the inspection process was to take all measures necessary to ensure that each joint was prepared and turned over to the applicators in conformance to the specifications and in a similar condition to all other joints.
PR-369-08609-R01 Online Gas Meter Cleaning
Authors: Gipson  , Trahan
Published: August 2023

To ensure proper operation and accuracy of Natural Gas meters, it is important that the meters and associated piping be maintained in a clean condition consistent with both manufacturer production and AGA report provisions. This can best be assured through a comprehensive diagnostic and in section program complete with efficient internal cleaning as required. The objective of this project was to provide a comparison between continuous chemical injection cleaning with the system remaining online and conventional manual disassembly and cleaning techniques with the system offline. Representative samples of fouling materials were collected from two designated meter locations for complete identification analysis and cleaning product screening. The results from these tests are intended to assist in selecting the most effective product for the online cleaning method.
PR-015-09209-R01 Test Facility for Pump Performance Characterization in Viscous Fluids - Phase I
Authors: Wilcox
Published: August 2023

In the liquids pipeline industry, large horsepower and flow pumps are used to transport liquid along the pipeline. When these pumps are purchased, they are performance tested with water. Performance tests are also sometimes conducted after a pump has been in operation for some time. The performance of a pump is different with water than with a viscous fluid (crude oil). Therefore, the performance results with water are corrected for viscosity. The Hydraulic Institute (HI) developed viscosity correction factors which are used to correct the pipeline pump performance results. These correction factors are based on test results with pump head and flows up to 430 ft and 1140 gpm, respectively. Pipeline size pumps easily have flows in the range of 10,000 to 50,000 gpm. The correction factors used for pipeline size pumps were derived from the HI lower flow and head correction factors. Therefore, the correction factors have an unknown error for larger flow and head pumps.
PR-266-07209-R01 Phase 2 - Assessment of the Robustness and Transportability of the Gas Turbine Model
Authors: Chapman  , Toema
Published: August 2023

This report presents the modeling study of a gas turbine combustor based on first engineering principles to fully characterize the nitrogen oxides (NOx) and carbon monoxide emissions (CO). The model is mainly focused on the emissions from the widely used lean-premixed, dry low-NOx combustor. The combustor is divided into several zones where each zone can be considered as a plug-flow reactor. Each of these zones is assumed to have a uniform pressure, temperature and perfect mixing between combustion species. The temperature of each zone is calculated using mass and energy balances along with heat transfer through the combustor liner. The emissions are calculated using well-know pollutant reaction schemes such as the Zeldovich mechanism in addition to other well-established semi-empirical correlations.
PR-218-103706-R02 Kiefner Review of NTSB Report PAR 09-01
Authors: Kiefner
Published: August 2023

This report provides a gap analysis of The National Transportation Safety Board (NTSB) Acci-dent Report NTSB PAR-09-01 titled "Rupture of Hazardous Liquid Pipeline with Release and Ignition of Propane Carmichael, Mississippi November 1, 2007" regarding the Dixie Pipeline Company failure. This report also provides peer review of the NTSB results and establishes the research needs to address longitudinal seam weld integrity for Electric Resistance Welded (ERW) pipe.