bluuebunny/crossref_metadata_2025 huggingface dataset:
L51602 Criteria for Hot Tap Welding Further Studies
Authors: Unknown Author
Published: August 2023

In the gas transmission industry there is a frequent need for modification of existing pipework. Modifications are made primarily by welding on additional pipes and branch connections to existing pipelines. The associated costs of shutting down a pipeline creates a situation whereby it becomes economically feasible to weld onto pipelines containing flowing, pressurized products. The risk of burn through and in particular, the susceptibility to cracking are greatly increased by the rapid cooling rates associated with the high heat sink effect of the flowing gas and in turn can result in excessive hardening of the heat affected zone in ferritic steels.

Edison Welding Institute developed new criteria for safe hot tap welding procedures on all ferritic steels. Their approach is based on correlating field measurements of the ability of the pipe to conduct heat (i.e., its heat-sink capacity) to the cooling rate of the weld. Laboratory welding trials with simulated branch and sleeve connections on live pipelines containing natural gas were used to validate the new criteria. The results indicate that structurally sound hot tap repairs can be made with a high level of confidence.
L51682 Ductile Fracture and Mechanical Behavior of Typical X42 and X80 Line-Pipe Steels
Authors: Leis
Published: August 2023

This report presents the results of Structural Integrity (SI) Task 1.11-1990, which was initiated to develop the properties for a steel that was typical of lower strength early vintage pipe and anothersteel that represents the more recent controlled-rolled high-strength and high-toughness pipe. Samples of X42 and X80 steels were chosen as the basis for study. The approach was to compare the properties for these steels with the behavior assumed in the analysis and embedded in the model formulation. If the behavior of the new materials is compatible with the current formulation then it can be concluded that the model can with minor changes and related validation be extended to a much broader scope of pipeline applications. This report presents the ductile-fracture and mechanical properties needed to implement the ductile-flaw-growth model and then comments on the modifications needed to adapt the model to this broader class of steels by comparison of the results presented with the formulation developed to address the steels in the earlier study.
L51800 Cathodic Protection Considerations for Pipelines with AC Mitigation Facilities
Authors: Gummow
Published: August 2023

Induced AC on pipelines, despite the installation of AC mitigation facilities, can still produce deleterious effects involving the safe operation of the pipeline, the effective operation of the cathodic protection system, and the safety of personnel. One of the most serious consequences of steady state induced AC is that AC corrosion can occur, even though the induced AC voltage has been reduced to less than 15V as required by the standards and notwithstanding cathodic protection levels that also satisfy the standards. Implementation of the findings of this report will result in improved effectiveness of CP systems, longer useful pipeline operation life and a reduction personnel safety hazards. This project resulted in a report identifying and avoiding those situations where AC mitigation techniques may reduce the effectiveness of the CP system.
L51719 Overview of Intergranular SCC Research Activities
Authors: Parkins
Published: August 2023

While much has been learned in the last 25 years of the mechanism and controlling parameters in the stress corrosion cracking of pipelines, remaining gaps in knowledge of the problem are indicated. The very early years of investigations followingthe recognition of the problem were concentrated on gathering field data and that was followed by about 20 years of research, largely carried out in laboratories, aimed at obtaining an understanding of the causes of pipelines stress corrosion cracking. While there remain matters that could be studied by laboratory-based research, there appears to be a stronger case for returning to field-based studies, with help in defining such from the increased understanding that has been developed since the early field studies.

This work gives an overview on the past 25 years of research concerned with the phenomenon of stress corrosion cracking (SCC) in high-pressure gas pipelines. But rather than review the various research programs in chronological order, the author proceeds with his review, after a brief historical introduction, in terms of the parameters that sequentially control SCC; the parameters being chemical environment, electro-potential, stress state (especially the influence of stress cycle) and pipeline steel susceptibility. Each parameter is treated as a \chapter\" and then the current state of knowledge for that parameter is summarized at the end of the chapter. The impact that some parameters could have on the ability to accurately model SCC in pipelines is explored and approaches to control of SCC are given in the final summary and recommendations.
L51692 Multiple Pipelines in Right-of-Way - Improved Pipe-To-Soil Potential Survey Methods
Authors: Thompson  , Lawson
Published: August 2023

Pipe-to-soil potential measurements are the primary means for monitoring the effectiveness of cathodic protection systems. All criteria for cathodic protection employ, in one form or another, a potential measurement of the pipe with respect to a reference electrode.

This research project was undertaken to determine what portion of a pipe is sampled by an above-ground potential measurement. One important area that has not yet been investigated is what portion of a pipe is sampled during a potential survey of a pipeline in a right-of-way containing multiple pipelines directly bonded to each other. The overall objective of this project was to improve the ability to interpret close interval on- and off-potential surveys in rights-of-way containing multiple pipelines. The project objective was accomplished by completing the following specific task oriented goals: (1) to expand the previously developed computer model to include multiple pipelines in the right-of-way, (2) to predict interaction effects between two pipelines in the same right-of-way, (3) to extend modeling activities to more complex pipeline situations by modeling specific case studies, and (4) to provide field verification of the modeling activities.
L51888 Development of Coupons for Monitoring Cathodic Protection Systems
Authors: Thompson  , Lawson
Published: August 2023

The use of coupons has been discussed and utilized for some time and is more prevalent in Europe than in the United States. Externally buried coupons have been utilized for different reasons including corrosion rate measurements, but their primary use has been for monitoring the effectiveness of a CP system. A detailed review of coupon studies is presented below. Renewed interest in the coupon technology was prompted by several studies performed by CC Technologies for PRCI that examined the use of off-potential measurements for evaluating the effectiveness of the CP system. These studies examined possible errors in the off-potential measurements including: Potential transients following the interruption of the CP system (spiking phenomenon). Interference due to multiple pipelines in the same right-of-way. Errors caused by long-line currents. Errors in monitoring local pipe conditions due to averaging large areas of pipe when making ground level pipe-to-soil potential measurements. In addition to the above studies which show conditions for which the off-potential measurements may not accurately represent the conditions locally on the pipe surface, a relatively common condition is the inability to interrupt all sources of the CP current on pipelines in congested areas or those structures with sacrificial anode cathodic protection directly bonded to the structure. Interpretation of pipe-to-soil potentials is made more difficult in areas of stray and/or telluric current activity. Therefore, there is a desire to utilize coupons as a more general tool for evaluating the level of CP. The areas targeted in this study are those areas for which the off-potential measurements are either difficult to perform or to interpret and for which a better means is needed for monitoring the CP level of the structure.

Beginning in 1992, PRCI funded a program for the development, proof of concept, and evaluation of the coupon technology as applied to monitoring cathodic protection effectiveness on underground pipelines. The objectives for this project were: To provide a proof of concept for the use of coupons as a method to monitor the effectiveness of CP without interruption of the CP System. (Phase I). To establish guidelines for the use of coupons as a monitoring methodology for determining the level of protection on a pipeline. (Phase II). To provide a better understanding of the relationship between the coupon and the surface condition of the pipe. (Phase III). To quantify the technology such that it can be used as an alternative to conventional monitoring practices, specifically as a means of applying an acceptable criteria for CP. (Phase III).

The scope of work included laboratory tests involving large soil boxes containing simulated coated-pipe segments with full size coupon test stations, finite element modeling of coupons near the pipe, full scale pipe tests at the Sugar Grove Test Facility and CC Technologies' Dublin, Ohio Pipe Test Facility, and test sites on operating pipelines throughout the United States.
L00450 Interpretation of Aquifer Gas Storage Conditions from Water Pumping Tests
Authors: Witherspoon
Published: August 2023

The use of aquifers for storing gas underground has posed new problems for the natural gas industry. One does not have the advantages of converting an existing gas field into a storage project. In such cases, the original gas accumulation is sufficient proof that a reservoir exists in which gas can be stored. In the case of aquifers, however, the operator must first find an adequate geologic structure in which a suitable reservoir rock is located. This usually is solved by the application of existing exploration techniques, although the search for an aquifer storage site is normally carried out in much more detail than would ever be considered necessary in exploring for oil or gas. The most critical problem that the operator must face in aquifer storage is that of determining the tightness of the caprock layers overlying the intended storage zone. Having found a suitable site, the operator must attempt to answer the question: "Will gas leak through the caprock?". A number of aquifer storage projects have been hampered by migration of gas out of the intended storage zone.
L51408 A Study of Restraint in Pipeline Girth Welds
Authors: Lazor
Published: August 2023

The stresses that develop across a weld are important since they may lead to weld cracking, may limit additional service stresses that can be applied and may influence the risk of brittle fracture, stress corrosion cracking or other aspects of service behavior. There has been significant progress in determining stresses around welds due to external loads such as lifting. There has, however, been considerable work published (mainly from Japan) on stresses in flat plates due to welding, and the associated theories are reasonably well developed. In particular, the concept of "intensity of restraint" has been introduced to provide some kind of measure of the "stiffness" of a joint before it is welded. This enables the stresses that develop to be related to the type of joint (thickness, size and configuration of plates, etc.). In developing these ideas, it has been necessary to measure experimentally the magnitude of the contractions that occur across welds in unrestrained and restrained welds together with the stresses developed. Much data for flat plate are available but little for pipe welds. This work aims at developing the restraint concepts for girth welds of pipes. The approach has been to measure the weld contractions and reaction stresses in a bench-top experiment using a 12-inch diameter pipe rotated beneath the welding head. A self-restraining system was designed in which shrinkage of the pipe was restrained by a smaller internal pipe attached with end pieces. Since such a system would be in equilibrium, restraining forces could be measured by compression of the central pipe as well as tension in the external pipe. The program was intended to provide basic data on shrinkage and stresses in pipe welding to determine whether any of the models developed for flat plate were applicable. The experiments were designed to show the effects of restraint level and welding parameters.
L51623 Environment Sensitive Cracking (Low pH Stress-Corrosion Cracking) of High Pressure Pipelines
Authors: Parkins
Published: August 2023

This is a review of the current situation relating to transgranular environment sensitive cracking of the type experienced on an in-service pipeline, by comparison with the commoner intergranular cracking experienced on many systems. It is probable that the cracking is not unique. Quite apart from the crack paths, there are other significant differences between the conditions in which the two types of cracking occur, particularly in relation to the environments involved, and sufficiently so to indicate that the mechanisms of cracking are different. The circumstances in which the two types of environment form are discussed. If the creation of a
reliable model for practical application to transgranular cracking is to be achieved, there is need for data relating to the effects of stressing conditions upon the crack nucleation and� growth rates of such cracks and of the circumstances in which these cracks coalesce.
L51718 Development and Validation of a Ductile Fracture Analysis Model
Authors: Kanninen M. F.
Published: August 2023

In close cooperation with the Centro Sviluppo Materiali (CSM) and SNAM of Italy, with several years of support from the PRCI NG-18 committee, the Southwest Research Institute (SwRI) has developed and validated a "first principles" predictive model for ductile fracture in a gas transmission pipeline. In particular, the coordinated SwRI and CSM projects for the PRC -supplemented by work contributed by SNAM - has established a theoretically valid methodology and an accompanying line pipe material characterization procedure for gas industry use. This progress provides a theoretically sound framework for designing and operating gas transmission pipelines to be without risk of a large-scale ductile fracture event. However, there remained two important aspects of this technology that needed to be addressed before practical use of the methodology could be made by gas transmission companies. First, because the preceding projects concentrated on pipes with natural gas, to cover the full range of gas transmission pipeline service, the approach needed to be extended to include the effects of gases rich in hydrocarbons. Second, as the number of full-scale pipe fracture experiments that were included in the developmental phase of the research were limited, other data for validation of the model needed to be identified and employed. These two aspects of the ductile fracture methodology development process were conducted concurrently, and have now been completed. The progress that has been provided in detail in this report. The work is culminated by a relation through which the methodology can be applied by pipeline engineers to assess the possibility of a ductile fracture propagation.

This report describes the development of a predictive model for ductile fracture in a gas transmission pipeline, thus providing a theoretically sound framework for designing and operating gas pipelines to be without risk of a large-scale ductile fracture event. The model represents an improvement on a number of empirical relations used in designing natural gas pipelines in that this model has been generalized to consider a wide-range of hydrocarbon contents and validated through both additional full-scale instrumented tests carried out by Centro Sviluppo Materiali of Italy and computer simulations conducted at Southwest Research Institute. Application of the model in pipeline design is based on determination of the maximum driving force for fracture, as described in the report, and contrasting this value with measured material resistance that provides a basis for assessing the likelihood of ductile fracture occurring. For existing pipelines the procedure can be used to obtain the maximum operating line pressure that will not put the pipeline at risk of ductile fracture.
L51759 Centerline Segregation in Plate and Strip for Linepipe Produced from Continuously Cast Slabs
Authors: Gray
Published: August 2023

Segregation in plate and linepipe can have an adverse effect on the mechanical properties, weldability and performance of plate and linepipe.

The present study was initiated as a result of field reports concerning incidents of severe chemical segregation in linepipe intended for use offshore. This research was initiated to develop a better understanding of the extent of segregation-related problems and to develop methodologies or tests which could be imposed by purchasers to eliminate future occurrences. The research was undertaken in three separate tasks as follows:

Task I Survey of pipeline industry experience, or incidents, involving segregation problems in continuously cast product.
Task II Survey of available means for controlling and monitoring of segregation and identification of methods suitable for detailed evaluation.
Task III Evaluation and technical assessment of promising segregation monitoring methods identified in Task II.

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L52302 Using Strain-Based Design in Conjunction with API RP 1111
Authors: DeGeer
Published: August 2023

The design section of API Recommended Practice 1111 for the Design, Construction, Operation and Maintenance of Offshore Hydrocarbon Pipelines is based on limit states concepts, cast in a simple and practical framework. Some strain-based criteria exist in the recommended practice (RP), but there are a number of load cases not explicitly addressed in the RP that could benefit from strain-based design methods. Given the advances in strain-based design methodology in recent years, there is a need to prepare a supplementary document describing how strain-based design approaches may be used in connection with the RP to produce better overall solutions and ultimately serve as a basis for enhancing the RP.
L52233 Evaluation of Hydrogen Cracking in Weld Metal Deposited Using Cellulosic-Coated Electrodes
Authors: Fiore  , Boring
Published: August 2023

Cellulosic-coated electrodes (primarily AWS EXX10-type) are traditionally used for "stovepipe" welding of pipelines because they are well suited for deposition of pipeline girth welds and are capable of high deposition rates when welding downhill. Despite advances in mechanized welding technology, development of low-hydrogen self-shielded flux-cored arc welding (FCAW) consumables, and substantial improvement of basic-coated low-hydrogen vertical-down shielded metal arc welding (SMAW) electrodes, manual pipeline welding using cellulosic-coated electrodes is still widely utilized throughout the world. Cellulosic-coated electrodes are also used for critical applications in offshore pipeline construction such as tie-in welds and repair welds.Hydrogen-assisted cracking can occur in both the weld metal and heat-affected zone (HAZ) regions of a welded joint, although HAZ hydrogen cracking is more common. Extensive work was undertaken in the 1970s and 1980s to study HAZ hydrogen cracking, and guidelines were developed to avoid HAZ hydrogen cracking by controlling heat input and preheat. Improvements in steelmaking practice and the trend toward leaner chemistries have also helped to alleviate HAZ hydrogen cracking.

The primary objectives of this project are to further define the conditions that can lead to hydrogen cracking in weld metal deposited using cellulosic-coated electrodes, in terms of operator preference (arc length), electrode properties, power supply selection, and materials handling. The results of the project are being used to develop welding guidelines, and if applicable, re-hydration guidelines to prevent weld metal hydrogen cracking.
L52244 Advanced Welding Repair and Remediation Methods for In-Service Pipelines
Authors: LaMorte  , Boring  , Porter
Published: August 2023

This project developed a prototype multi-axis automatic welding system with adaptive control and tracking for use on in-service welding repairs on liquid and gas transmission pipelines. The system is capable of deploying either gas metal arc welding (GMAW) or flux cored arc welding (FCAW) to weld pressure-containing sleeves (Type B), to weld reinforcement sleeves (Type A), or to directly deposit a layer of weld over an area to replace metal loss due to corrosion. The welding system was field tested at TransCanada in North Bay, Ontario and was demonstrated during a workshop at Edison Welding Institute in Columbus, Ohio. In addition, preliminary in-service welding trials with GMAW and FCAW were performed on high strength pipeline steels (X80, X100 and X120) to determine the susceptibility of hydrogen cracking, under simulated in-service welding conditions.
L51779 Reliability-Based Fitness for Service Assessment of Welds
Authors: Warke R. W. , Ferregut C.
Published: August 2023

Requirements for the fabrication and inspection of transmission pipeline girth welds are given in national codes such as API 1104, CSA Z662, and BS 4515. Their objective is to ensure an acceptable level of quality, and implicitly, operational safety. They seek to achieve this by imposing workmanship standards which prescribe the allowable size and frequency of various discontinuities. These standards are largely arbitrary and thus highly conservative in most situations. However, the potential for economic benefit, an increasing demand for safety, and the development of fracture mechanics technology have motivated the inclusion of optional fitness-for-service (FFS)-based flaw acceptance criteria. Two major objectives of the present work were to educate those unfamiliar with structural reliability concepts, particularly as they apply to pipeline integrity, and review the worldwide codification of LRFD for industries that fabricate and maintain welded structures. The final objective was to develop a library of PSFs for pipeline girth weld flaw assessment thereby aligning girth weld fitness-for-service assessment procedures with emerging LRFD codes for transmission pipelines.
L52325 Assessment of Geosynthetic Fabrics to Reduce Soil Loads on Buried Pipelines - Phase I and II
Authors: Honegger  , Wijewickreme  , Monroy
Published: August 2023

High soil loads on buried pipelines can lead to unacceptably high pipeline strains developed in response to permanent ground displacement. Common causes of permanent ground displacement are related to slope instability as a result of heavy precipitation or ground subsidence. In addition, several permanent ground displacement hazards are related to earthquakes including surface fault displacement, triggered landslide movement, surface ground settlement related to liquefaction, and lateral spread displacement. Result: Four specific areas of investigation were completed: 1.Performed baseline tests in moist sand to confirm minimal difference in horizontal soil restraint between moist and dry sand. 2.Performed tests to gauge the variation in horizontal load reduction with separation between the pipe and an inclined trench wall lined with two layers of geotextile. 3.Performed tests in compacted 19 mm (0.75 in) minus sand and crushed limestone (referred to locally in British Columbia as road mulch) to attempt to provide larger difference between horizontal forces developed with and without lining a trench wall with geotextile. 4.Performed tests to attempt to confirm oblique horizontal-axial soil restraint behavior reported in small-scale tests and centrifuge tests. Benefit: Rather than undertake further physical testing to better understand how the presence of single or dual layers of geotextile fabric changes the mechanisms by which soil restraint develops for horizontal ground displacement, future efforts should focus on numerical simulation preferably using discrete element methods. Until full-scale test data are available to confirm consistent prediction of oblique horizontal-axial soil restraint, the practice of treating horizontal and axial soil springs independently in the analysis of buried pipeline response to ground displacement, as is the current practice, should be maintained.
L52131 Gap Analysis of Location Techniques for CP Shielding
Authors: Brossia  , Song  , Sridhar
Published: August 2023

To mitigate and prevent corrosion of pipelines, cathodic protection (CP) is imposed in the form of impressed current, sacrificial anodes (e.g., Mg ribbons), or a combination of the two. To reduce the CP current load and aid in corrosion prevention, most pipelines are also coated with an organic coating. Over the course of time, it has been noted that the coatings tend to degrade leading to disbondments, holidays, and tares. For the most part, the presence of holidays and tares are not of tremendous concern as the CP system is in place to protect them and if needed the current output of the system can be increased to compensate for the formation of new defects. Disbondments, however, can be a source of significant concern because in some case the CP does not penetrate and protect the disbonded region. This has been shown to be a leading factor in enhanced corrosion in the disbonded region as well as in the development of SCC failures in several pipeline systems. Such regions are difficult to protect with CP as they are shielded from the current (i.e., there is insufficient current flow for adequate protection), reflecting a condition known as CP shielding. CP shielding can occur for reasons other than coating disbondments, including permafrost, use of insulating panels to prevent contact of intersecting pipelines, various barrier materials, rocks, tree roots, and other naturally occurring high resistance materials, and often times casings.

Even though not all cases of CP shielding are detrimental, it is evident that detecting and locating possible areas of CP shielding is of prime concern as these locations are potentially subject to higher corrosion rates and possible SCC. The objective of this project was to review and discuss current practices used to detect CP shielding as well as to conduct a gap analysis to explore other promising technologies that may prove useful if implemented. Because there are two main circumstances under which CP shielding is investigated, the discussion centers on detecting CP shielding from above ground and post hole excavations.
L00280 Noise Abatement Volume III - Blow-off Noise Suppression and Regulator Valve Noise Generation
Authors: Kiefner  , Wall
Published: August 2023

The first section of this report contains techniques for designing silencers to suppress the noise produced during high pressure gas blow-offs. Both complex analytical techniques and simplified design charts are presented; the charts allow users to design silencers based desired noise reduction, pipeline pressure, and blow-off size. The second section of the report discusses the noise generation characteristics of regulator waves.
L51412 Evaluation of AE Analysis Capability for Buried Natural Gas Pipelines
Authors: Kiefner  , Stulen
Published: August 2023

An evaluation of acoustic emissions (AE) monitoring was conducted on a 5,450-foot long segment of 26-inch diameter pipe in Dutch John, Utah. Various types of defects were artificially induced in the pipeline to determine if AE monitoring could locate these defects with transducers spaced 500 feet apart. A secondary objective of the study was to develop a standard test method for AE field inspection of gas and liquid pipelines. The results show that AE monitoring can locate severe longitudinal defects at pressures as low as 30% to 50% of the failure pressures (for some types of defects). AE monitoring was not effective for locating circumferential defects subjected to loading from internal pressure.
L51513 Finite Element Model for the Remote Field Eddy Current Effect
Authors: Lord
Published: August 2023

Describes the methods for producing a code toward the development of a numerical finite element mode to study the remote eddy current (RFEC) effect as it pertains to steel pipelines. Further specific research plus developing a 3-D code are included as recommendations. See also L51595.
PR-460-134506-R01 Development of a Modern Assessment Method for Longitudinal Seam Weld Cracks
Authors: Anderson
Published: August 2023

This research effort was aimed at developing a state-of-the-art fracture model for pipelines with longitudinal seam weld cracks. Approximately 200 finite element simulations were performed, and the results were fit to a parametric equation. The report contains the theoretical framework of the model, a description of the finite element study, and a set of tables that contain fitting constants for the model. The benefit of this research is the creation of a significantly more accurate model to predict burst pressure of pipes with longitudinal seam weld flaws. Increased accuracy in predictions will improve the integrity of seam welded pipe.
L51487 Predict the Interaction of Fracture Toughness and Constraint Effects for Surface Cracked Pipe
Authors: Wilkowski
Published: August 2023

This report summarizes a program designed to quantify the disagreement between the standard t x 2t bend specimen and surface-cracked pipe data. The effect of untracked ligament length on upper-shelf toughness was also investigated. Ultimately, the findings will have application to pipeline girth welds. But in this first step, unwelded line-pipe steel specimens were used throughout this investigation. Obviously, weld metal specimen data would be more directly applicable to welded pipe. However, weld metal test data exhibit more scatter than base metal data (largely due to material non-homogeneity). This scatter could cloud the general data trends under investigation. Consequently, base metal specimens were used to more clearly establish these trends. This will form a basis for further investigations on weld metals.
L52342 Development of Procedure for Low-Constraint Toughness Testing Using a Single-Specimen Technique
Authors: Shen  , Gianetto  , Tyson
Published: August 2023

Pipelines from remote frontier regions are increasingly required to have adequate resistance to large deformations such as that caused by ground movement. In response to this, �strain-based design"� has been developed to enable assessment of imperfections at applied strains beyond yield. In addition, it is proposed to take advantage of the increased apparent toughness of pipe under low constraint, such as girth weld imperfections under axial tension, compared with the high-constraint toughness measured in conventional tests such as ASTM E1290 [1]. Application of low-constraint testing has been dvantageously applied in assessment of toughness for offshore pipeline projects. Also in the pipeline industry, demands on new pipeline projects include low design temperatures as well as high strain capacity. At the same time, increased strength is specified, which increases the level of required toughness. These factors make it increasingly important to assure weldment toughness, in particular to ensure that the failure mode remains ductile. It is well known that brittle cleavage is especially sensitive to constraint, and the availability of a toughness test that would reproduce field conditions would enable more rational development and acceptance of candidate welds and, in particular, enable more appropriate testing of weld heat-affected zones.

This work was performed for specific application to surface circumferential cracks in pipe under strain-based design, for which the best constraint matching has been found to occur for clamped single-edge tension (SE(T)) specimens with H/W=10. For this geometry, a test procedure similar to that of ASTM E1820-06 for single-edge bend (SE(B)) and compact tension (C(T)) specimens was developed for J-resistance tests using a single-specimen technique. All the equations used in the procedure, including those for evaluation of J-integrals from the area under load/plastic crack mouth opening displacement (CMOD) curves, and evaluation of crack length from unloading compliance including rotation correction, were developed using finite element analysis (FEA) with a range of crack depths, focusing on a/W= 0.2 to 0.5 which is of most practical interest. The present procedure is compared with that of E1820 for SE(B) testing regarding evaluation of J-integral with crack growth correction, crack length evaluation, and correction of compliance for rotation.
PR-218-063511-R02 A Model for Predicting the Severity of Pipeline Damage Identified by In-Line Inspection
Authors: Francini  , Yoosef-Ghodsi
Published: August 2023

The development of the damage severity model will provide a significantly improved technical basis to evaluate potential threats and develop general guidance for the industry. When combined with the results from parallel PRCI projects, this effort will form the basis for delivering a new suite of engineering tools and guidance to the industry on how to evaluate the potential hazards associated with mechanical damage.
PR-309-08208-R01 A Survey of Diagnostics Techniques for Compressor Engines
Authors: Beshouri
Published: August 2023

The pipeline workforce faces several challenges over the next few years. Unprecedented numbers of experienced staff are retiring. They are being replaced by a smaller, younger workforce tasked with more responsibilities and therefore unable to develop specific expertise while roving crews fill labor gaps resulting in less experience with each individual engine compressor. To maintain, if not improve reliability and reduce maintenance costs better analysis tools are needed to fill the experience and expertise gap and assist with troubleshooting and diagnosis. Concurrently, regulatory expectations appear to be shifting from Continuous Emissions Monitoring System (CEMS) like quantifying systems to Green-light/Red-light automotive like On Board Diagnostics (OBD). OBD approaches rely on the proper operation of already installed sensors and actuators to maintain emissions compliance and can be very cost effective. This study investigated diagnostic methods to address both opportunities based on experience in related industries.
PR-309-04200-R02 Field Testing of Ion Sense and Pressure Ratio Technology On a TLA-6
Authors: Beshouri  , Richter
Published: August 2023

This project conducted field optimization and long term testing on a typical Two Stroke Cycle (2SC) Lean bum pipeline engine to assess the feasibility of cylinder level diagnostics, air/fuel ratio balancing and air/fuel ratio control using ion sensing. Compare the performance with current and potential in-cylinder pressure based methods.
PR-179-05211-R01 GMV Upgrades - Final Report
Authors: Bennett  , Nelson  , Olsen
Published: August 2023

The GMV Upgrade Proposal provided funding to prepare the Cooper-Bessemer GMV engine test bed for 2006 PRCI research projects. The test bed, originally installed over a decade ago, relies of several different plant systems. These systems require occasional investment to update and repair. Engines and Energy Conversion Laboratory (EECL) staff and PRCI members collaborated to decide upon several important investment areas which were directly address by this project.
PR-218-104503-R01 Field-Expanded Line Pipe Causes Effects on Pipeline Safety and Appropriate Responses
Authors: Rosenfeld  , Munoz
Published: August 2023

Several pipeline construction projects executed between 2007 and 2009 experienced observations of pipe expansion following hydrostatic testing in the field to pressure levels produced hoop stresses near or above 100% SMYS. Owing to biaxial strength effects, the test conditions would not have been expected to cause pipe having the specified strength properties to yield during the test. The affected pipes were 36-inch OD and 42-inch OD, specified to meet the requirements of API 5L Grade X70 supplied by several manufacturers, with plate obtained from various sources. Some projects had only a few joints of pipe affected, while others experienced more widespread occurrence. The occurrence of expanded pipe joints implied that the yield strength properties of the affected pipe did not conform to specified minimum values. This study reviewed an industry-developed process for determining whether observed pipe expansion was caused by nonconformity to specifications, or by other external factors. The project also summarized current and historical industry experience with expansion of pipe during testing, reviewed factors that explain how pipe manufacturing affects finished pipe properties, reviewed how pipe strength test methods affect test results, determined how expansion affects pipeline integrity threats, made recommendations for a suitable allowable amount of diameter expansion, and made recommendations for minimizing the likelihood of obtaining pipe that could be affected during normal testing.
PR-015-11702-R01 Evaluation of Enhanced Diagnostics for Orifice Meters
Authors: George  , Hawley
Published: August 2023

A large installed base of orifice meters, many installed where newer technology meters are impractical, accounts for a significant fraction of the measured volume of natural gas in the United States. Ultrasonic meters are newer technology meters that provide integrated diagnostics to monitor the meters health and identify flow problems such as distorted velocity profiles and other operational issues. The need exists for similar diagnostics for orifice meters to identify operational causes of measurement errors (and possibly measure their magnitudes), allow users to perform orifice meter maintenance as needed, reduce maintenance costs, and reduce the fiscal impact of significant measurement errors. Research was conducted to identify and recommend candidate technologies for development into practical, cost-effective orifice meter diagnostic tools..
PR-015-12605-R01 Effect of Upstream Piping Configuration on Ultrasonic Meter Bias
Authors: Hawley  , Owston
Published: August 2023

This research investigated the effects on ultrasonic meter performance of header configurations upstream from a default AGA-9 meter run. To minimize the expense of experimentally testing numerous header configurations, the approach of this research was to use Computational Fluid Dynamics (CFD) to model multiple header configurations. The CFD model used for this research was developed by using experimental data from a previous PRCI-funded project (Contract PR-015-10603) to tune and validate the model. Twelve header configurations were evaluated using the developed CFD model. The 12 header configurations were selected based on input from the PRCI project committee. The effect of the headers on measurement error was assessed for Daniel and Instromet path configurations.
PR-535-143745-R01 ART Scan Qualification Study
Authors: Fleury Wayne , Toskedal Jan Ove
Published: August 2023

This qualification study is based on the need for a new technology in the asset integrity lifecycle of pipelines including Subsea infrastructure. As of today it is challenging to identify a technology that combines adequate measurement accuracy combined with the ability to operate in gaseous atmosphere found inside natural gas pipelines. Halfwave�s inspection method developed over the last two decades is based on Acoustic Reso-nance Technology (ART), which utilizes the natural frequencies of the pipe wall to determine the remaining wall thickness. The most prominent advantages of ART comprise (i) direct measure-ments of wall thickness with a accuracy within 0.2 mm (95% c.l.), (ii) the broad-band frequency range enables measurements in pressurized gas, avoiding a liquid couplant, and (iii) the transducer matrix with (a flexible) stand-off to the wall enables high-resolution internal geometry mapping of the pipeline to a resolution within 50 �m (95% c.l.). Additional benefits include the ability to detect disbondmant of external coating and delamination in the pipe wall material. ART is a well-known inspection technology dating back to the 1940s in e.g. the aviation industry, scanning air craft wings, and has also been extensively used in connection with integrity measure-ment of down-hole casings (cf. e.g. the USIT tool, by Schlumberger). However, the last decade�s development of broad-band transducers combined with a surge in storage technology has moved the operational envelope and accuracy of ART a quantum leap ahead, offering much more relia-bility in the integrity evaluations of natural gas pipelines. In turn this gives significantly enhanced decision confidence for the pipeline operator. This document will provide a description of ART and also Halfwave�s application of ART within the Oil and Gas industry.
PR-179-14202-R01 Field Evaluation of Timed Power Cylinder Lube Oil Injection
Authors: Olsen  , Stevens
Published: August 2023

A timed lube oil injection system was developed for a field engine to improve power cylinder lubrication. The injection system used advanced prototype electronic injectors. The system was installed on a Cooper GMVA-10 located in West Virginia. A total of four cylinders were included in the study, two for the timed system and two for the baseline mechanical system. Cylinder wall lubrication, cylinder wear, piston wear, and ring wear tests were planned for various engine run times. The prototype timed lube oil system operated essentially until the prototype injector end-of-life was reached at about 1,200 hours. The project was discontinued because of injector issues and the site required a high level availability of the engine for gas compression.
PR-318-06701-R01 Predicting and Mitigating Salt Precipitation
Authors: Weiss
Published: August 2023

Brine solutions are often produced during gas storage operations, and when these solutions encounter changing temperature or pressure, salt can precipitate. This salt (NaCl) can impair productivity and may even result in abandonment of wells. Dilution with fresh water is the preferred method of mitigating the salt buildup. Existing salt deposits are dissolved with fresh water. Additionally, fresh water is used as a produced water diluent to reduce supersaturation with respect to NaCl. However, this can be expensive depending on the method of application, and as fresh water becomes scarcer, the method will become more expensive. A number of chemicals are reported to reduce or prevent salt deposition. Among them are ferrocyanide and some organic molecules such as nitrilotriacetic acid and nitrilotriacetamide (NTAm). These inhibitors are thought to prevent salt precipitation by crystal modification or by interfering with crystal growth. Their effectiveness, however, varies with their concentration and the chemistry of the brines. For example, ferrocyanide is a very effective salt inhibitor; however, at low pH or in the presence of large amounts of iron it decomposes rendering it ineffective. As shown in Figs. 1 and 2 where supersaturated solutions of NaCl are cooled to room temperature, the performance of both chemicals is reduced as the reservoir water increases in calcium and/or magnesium, eventually becoming ineffective. But even when precipitate is formed, both inhibitors affect the properties of the precipitate so that there is no caking with no tendency to form large crystals associated with sodium chloride scale. The questions concerning the environmental issues associated with ferrocyanide that arose during Phase I are addressed in this report.
PR-004-12602-R01 Performance of H2S Sensors - Unblinded
Authors: Donatello  , Janos  , Crippen
Published: August 2023

Three hydrogen sulfide (H2S) monitors calibrated to detect concentrations between the ranges of zero to fifty parts per million (ppm) were acquired by the PRCI project advisory team and sent to GTI for evaluation. The three tested monitors were from different manufacturers using different detection methods and technologies. Each of the three H2S monitors was evaluated using testing protocols to determine the accuracy, precision, and signal response of each monitor.
PR-186-063515-R01 Prevention of Internal SCC in Ethanol Pipelines
Authors: Bruno
Published: August 2023

Stress-corrosion cracking has been observed in carbon steels in contact with fuel grade ethanol. The scope of this project consists of an up-to-date summary of industry experience and laboratory test results that can be used in the development of guidelines for transporting ethanol by pipeline while avoiding stress corrosion cracking.
PR-319-05303-R01 Robotic Platform for the Inspection of Unpiggable Pipelines Under Live Conditions
Authors: NYSEARCH
Published: August 2023

This report outlines work completed under the first phase of TIGRE, which resulted in the development and laboratory demonstration of a full-scale live-pipe NDE In-Line-Inspection (ILI) robot system for use in high-pressure (
PR-312-12208-R04 NO2-NOx Ratio Data Compilation and Assessment
Authors: Panek  , McCarthy  , Drayton
Published: August 2023

When modeling NO2 impacts from combustion sources, justification is required to receive approval of a representative in-stack NO2/NOx ratio, which is a key model input when using advanced modeling tiers that consider plume chemistry. A September 30, 2014 EPA memorandum requires approval by the Regional Office on a case-by-case basis regarding the selection and application of the in-stack NO2/NOx ratio. The EPA Tier 2 Ambient Ratio Method (ARM2) and Tier 3 Ozone Limiting Method (OLM) and Plume Volume Molar Ratio Method (PVMRM) NO2 methods require an in-stack NO2/NOx ratio (ISR) as an input to AERMOD. Selecting an in-stack ratio (ISR) is a controlling factor in the determination of NO2 impacts, particularly when the actual ISR is lower than EPA default values, and maximum modeled NO2 impacts occur at receptors close to the emissions source. EPA initiated an effort to collect source test data and address the need for additional NO2/NOx ISR data in August 2012. This memorandum and accompanying dataset support this data request by providing ISR values that can be applied for common natural gas-fired reciprocating engines and turbines used as compressor drivers.
PR-306-123740-R01 Comparative Analysis of Pipeline Inspection Technologies Using Guided Waves
Authors: Pit Yann Le , Caron Didier , Acker Benoit
Published: August 2023

This document describes the analysis of performances of five non-destructive testing technologies for pipelines by propagation of ultrasound waves guided within the thickness along the axial direction. The tested tools are tools available on the market at the time that this document was written. Their individual performances have been analysed using an identical operating protocol so that they can be compared with each other. A comparative analysis has been made, so that the configurations for which the use of guided waves may or may not be envisaged can be deduced.�
PR-000-16209-Z01 Demonstration of Continuous Equipment Performance Monitoring
Authors: Choquette Gary
Published: August 2023

The Pipeline Research Council International has funded multiple projects focusing on using reciprocating engine operating data to diagnose combustion problems. This effort extends those techniques on reciprocating compressor units including the gas compressor, main bearings, and ancillary equipment (e. g., turbocharger, aftercooler, pumps). In addition, additional combustion monitoring techniques are described that can be implemented on most existing mainline compressor units used in the industry.

Includes macro enabled spreadsheets that perform modeling fits for turbocharger and power cylinder exhaust temperatures.