bluuebunny/crossref_metadata_2025 huggingface dataset:
L52026 Improved Prediction of Burnthrough for In-Service Welding
Authors: Eilerts
Published: August 2023

Experiments were conducted to evaluate the effect of pressure on burnthrough risk.� The results indicate that hoop stress has a significant effect for thin-wall pipe.� The experimental data was used to develop and evaluate an alternative burnthrough prediction approach that accounts for pressure in the pipe.� The approach that was developed assumes that the volume of heated metal under the arc behaves similar to an area of metal loss caused by corrosion pitting.� An equivalent pit size is determined from the pipe diameter and wall thickness and the calculated weld penetration.� The predicted burst pressure (i.e., the pressure limit) is then determined using RSTRENG.� While this approach was shown to be relatively accurate for the experimental welds that were made, it does not consider the removal of heat by the contents and it was evaluated for a limited range of conditions.
L52055 Improve Root Pass Quality for In-Service Branch Connection Welding
Authors: Bruce  , Boring
Published: August 2023

In the present project, a workscope similar to that used in the previous work for PRCI was followed.� The initial task consisted of identifying candidate processes and practices for depositing the root pass between a stub-on-type branch connection and an in-service pipeline.� Consumables for selected processes and practices were then procured and evaluated for their low-hydrogen characteristics.� In the next task, procedure development trials were carried out in small scale under simulated conditions to verify the suitability of candidate processes and practices and to determine the required welding parameters.� In the final task, procedures were qualified in full-scale, again under simulated conditions, to the requirements of relevant industry codes.�
NR198308 Design and Optimization of Mechanical Crack Arrestors for Pipelines
Authors: Wilkowski  , Scott  , Maxey
Published: August 2023

For natural gas or liquid CO2 pipelines, unstable ductile fracture can occur when the pressure at the propagating crack tip is sufficient to cause the crack driving force to exceed the fracture resistance of the line pipe material. In the past, when these conditions existed, unstable ductile fractures have been known to propagate for significant distances.

The objective was to investigate the ability of various designs to arrest an axially propagating ductile fracture and to optimize the design of crack arrestors. The experimental evaluations involved a scale model approach to evaluate the different arrestor designs. By testing two different sizes of pipe and a variety of test conditions, it was possible to evaluate the ability of scale model experimental data to predict full-scale behavior. By normalizing the arrestor length and radial clearance to the pipe diameter, the arrest/propagate boundary lines for various arrestor designs were equally effective in describing the behavior of crack arrestors thus adding credence to the contention that the model crack arrestor experiments can predict full-scale behavior.
L52007 Experimental Validation of Methods for Assessing Closely Spaced Corrosion Defects
Authors: Chauhan  , Wood
Published: August 2023

A full-scale burst test program was devised and agreed with the PRCI Materials Technical Committee Ad Hoc group. The work was undertaken over a two year period, 2003 and 2004. Due to budget constraints, only one pipe diameter and material was chosen for the test program. This was 24� (610 mm) outside diameter (OD) by 7.9 mm wall thickness, welded ERW steel linepipe of material API 5L grade B/X42. The criterion that defects separated by a distance of 6t or less will interact is over conservative. New rules for interaction, derived using non-linear finite element analyses and validated using full scale burst testing, have been derived for closely spaced metal loss interacting defects in pipelines. New, robust interaction rules for assessing corrosion metal loss defects in pipelines have been formulated for use by the pipeline industry.
L52034 Software for Estimating the Lifetime Cost of High Strength High Design Factor Pipelines
Authors: Fuglem
Published: August 2023

The objective of this project was to develop as software program to calculate the lifetime cost differential between pipelines designed for different combinations of steel grade and design factor. It is intended to evaluate the economic implications of using higher yield strength pipes and design factor for any given pipeline project. In each case, the possible failure modes were considered and the level of mechanical damage and corrosion maintenance required to achieve adequate reliability levels were determined.
HIX1IYS Nonlinear Harmonic Based Mechanical Damage Severity for Delayed Failures in Pipelines
Authors: Chell  , Crouch
Published: August 2023

The objectives of the current work are to (1) provide an assessment of the capabilities of the nonlinear harmonic (NLH) method to detect gouged dents in pressurized pipelines; (2) rank the severity of the detected defects against delayed failure; (3) provide information related to the remaining lives of detected defects when fatigue damage from cyclic pressure changes is the time-dependent mechanism controlling delayed failure; and (4) transfer the developed NLHbased defect severity criteria to an inline inspection vendor, Tuboscope Pipeline Services. An ancillary objective is to assess the capability of NLH probes to detect strain anomalies produced by crack-like flaws in the outside surfaces of pressurized pipes.

In this project, the assessment of the capabilities of NLH to detect and rank the severity of
defects is based on the analysis of results obtained from NLH measurements performed over the inside surfaces of pressurized pipe sections containing gouged dents subjected to cyclic pressure changes (fatigue loading) that eventually resulted in failure (leakage) at defects, and NLH scans of statically pressurized pipes containing crack-like machined notches.
L52050 Welding of Tie-ins in X100
Authors: Gianetto  , Bowker
Published: August 2023

Technology development for welding an X100 pipeline has the aim of reducing the capital expenditure required to build new, long distance pipelines. The results from the proposed project will specifically highlight, through a validated database of welding procedures and detailed property assessment, the range of tie-in welding procedures and processes that are suitable for an X100 pipeline.
GRl-90-0337 Identification of Injected Storage Gas
Authors: Thompson  , Anderson
Published: August 2023

This project developed and evaluated methods for distinguishing between natural gases from different sources. Identification of particular "batches" of gas can be of considerable importance. For example, means of distinguishing between gases can demonstrate whether a gas appearing at the surface over a storage area is migrating storage gas or is gas formed by bacterial action above the storage zone. As another example, identification methods can allow detection of migration from a storage zone to an adjacent production zone.

Two general methods were evaluated/developed in this project; tracers and compositional methods. Relative migration rates of a series of potential tracers were evaluated under a variety of conditions and in varying reservoir materials. Tracers having the best migration characteristics were identified. Potential tracers (either present in natural gas or added) which are not detected by electron capture or flame ionization detectors need improved methods of detection. The discharge ionization detector was evaluated for the detection of argon, carbon dioxide, carbon monoxide, Freon-14 (carbon tetrafluoride), and neon.

Two computer programs, based on regression and factor analysis methods, to aid in the identification of gases using compositional analyses, were further developed and improved.
PR-015-05600-R01 Assessment of Sampling Systems for Monitoring Water Vapor in Natural Gas Streams
Authors: Barajas  , George
Published: August 2023

Research has been conducted to assess the usefulness of various sampling and delivery methods in transporting a representative sample of a natural gas stream for analysis of moisture content. Three sampling configurations commonly used by the natural gas industry were evaluated, including a sample system with a regulated probe heated above ambient conditions, the same system held at a constant temperature simulating ambient conditions, and a heated sample system incorporating a membrane filter. Each configuration was used to transport samples of distribution-quality natural gas with levels of water vapor within common tariff limits, as well as samples of a water-saturated stream of methane simulating a common dehydration system upset. The time response of samples in each configuration to step changes in water vapor content between these two conditions was also evaluated. Measurements were performed using both manual chilled mirror dew point testers and automated analyzers.
L51864 Protocol to Prioritize Sites for High-pH Stress Corrosion Cracking on Gas Pipelines
Authors: Eiber  , Leis
Published: August 2023

This program developed a stress-corrosion cracking (SCC) protocol for use in assessing the likelihood of the conditions necessary for high pH SCC on individual pipeline segments and an SCC integrity management plan to assist operators in selecting appropriate remedial actions depending on whether SCC is located and the potential consequences. This protocol was developed as a conservative guideline based on existing knowledge at the time of development. This high pH SCC protocol was validated using data from 15 SCC service incidents collected during the conduct of this program and three test cases on pipelines without SCC available from another SCC protocol. An SCC Likelihood Index was developed that provides index values from 40 to 140.
L51490 Experimental Stress Analysis of Pipeline Girth Welds
Authors: Lazor  , Glover
Published: August 2023

Also PR-164-170. Examines the effect of welding procedures on the contraction behavior of linepipe due to girth welding using a range of standard field conditions and the resulting residual stress distribution.
NR198404 Properties of Induction Hot Bends Fabricated from High-Strength Cold-Expanded Pipe
Authors: Williams
Published: August 2023

This report presents the results of an investigation conducted at Battelle by the Pipeline Research Committee of the Pipeline Research Institute to investigate the structure/property relationships of several pipe bends fabricated from high-strength cold-expanded pipe using the induction-hot-bending process.

Interest has been growing in recent years in the use in gas-transmission lines of bends fabricated by the induction-hot-bending process. In this process, a pipe bend of a desired radius is produced by slowly pushing a pipe through an induction coil and deforming the narrow heated band that is developed as the pipe progresses through the induction coil. The maximum temperature to which the band is heated usually exceeds the upper critical temperature, 1500 to 1600F for line-pipe steels. Immediately after passing through the coil, the heated band is usually water quenched. Time above the upper critical temperature is short, usually only 1 to 2 minutes, but this is sufficient to transform the original structure of the pipe to austenite. Thus, after quenching, the pipe structure may consist of a number of different components, depending upon pipe composition and cooling rate, such as ferrite, pearlite, bainite, martensite, or combinations of these. If necessary to achieve the properties desired in the bend, the entire pipe bend, including the unbent tangent ends, may be tempered after fabrication.
L51475 Most Negative Potential Prior to the Onset of Significant Hydrogen Evaluation in a Crevice Task 2
Authors: Holbrook
Published: August 2023

Discusses the most negative cathodic protection potential that can be applied before significant evolution of hydrogen gas occurs at a holiday in a line pipe coating and the extent to which SCC is promoted beneath both unblocked and blocked disbonded pipeline coatings due to the decay of the potential distribution along the disbondment. Experiments on hydrogen evolution from exposed steel coupons and measurement of potential and current distributions beneath simulated disbonded pipeline coatings were conducted.
PR-214-05502-R01 Application of Fatigue Analysis Procedures Using Pipeline SCADA Data
Authors: Carrol
Published: August 2023

Fatigue life prediction for in-service pipelines can vary considerably, with one of the prime sources of variability being the pipeline operating pressure data typically captured and archived using a Supervisor Control and Data Acquisition (SCADA) system. SCADA systems may operate differently from one system to another and the records can be significantly different on the basis of the operational parameter sampling technique. Operating pressure data is a key input into integrity analysis for pipelines containing defects. BMT Fleet has collected close to 200 pressure data sets and has been investigating the sensitivity of fatigue life predictions for a number of pipeline operators for weld defects, dents, wrinkles, etc. on an individual basis. A strong understanding of the variability of the results has been obtained, but not formally presented in a comprehensive guidance document.The goal of the present investigation is to determine the impact of various precedures used to collect SCADA data on the resulting fatigue life predictions for defects. Based upon the analysis conducted, recommendations will be provided to outline techniques that should be applied to collecting SCADA data and for the subsequent use in integrity analysis processes. Procedures will be discussed to ensure that fatigue assessments based upon SCADA data are acceptably accurate, reliable and reproducible.
L52080 Burnthrough Limits for In-Service Welding
Authors: Bruce  , Boring
Published: August 2023

An initial series of experiments was conducted in thin wall pipe [(0.125 to 0.188 in. (3.2 to 4.8 mm)] to investigate the effect of pressure and welding direction on the risk of burnthrough.� A second series of experiments was conducted to investigate the effect of other welding variables, including electrode angle, electrode polarity, and welding against the edge of a full-encirclement sleeve.� The third series of experiments concentrated on developing limits for welding onto in-service pipelines thinner than 0.125 in. (3.2 mm).�
L51930 Optimized Sampling Frequencies for Weld Reliability Assessments of Long Pipeline Segments
Authors: Thacker
Published: August 2023

This project responds to a need to obtain statistically adequate quantities of input data for probabilistic assessments of girth welded pipelines. It is desirable to limit the data collection efforts to that warranted by overall reliability and confidence requirements. This is motivated by the challenge of limited and/or high-cost access to in-service pipelines for property measurement and flaw inspection.

The goal of this project was to develop a methodology for specifying the minimum, cost-optimized sampling frequency for each of the model input parameters in a multiple girth weld fitness-for-service (FFS) assessment. The sampling frequency specifies the number of samples for each of the model variables to minimize the given cost function. The methodology is based on a user-specified confidence level for the computed reliability of a given pipeline segment (or segments), as well as the estimated per-sample cost of obtaining data for each parameter. The methodology is implemented as an add-on module in the GirthRel computer program and all interactions with the software occur through an additional graphical user interface screen in GirthRel.
L51512 Crankshaft Technology Evaluation
Authors: Smalley
Published: August 2023

Technical summary based on an industry survey of requirements identified by reciprocating engine compressors in the area of crankshaft stress and alignment related research.
L41015 Feasibility of Inert-Gas Cushions in Gas Storages
Authors: Walker
Published: August 2023

The use of permeable underground formations to store natural gas for subsequent withdrawal has assumed major importance in recent years. One of the requirements for such operations is an initial quantity (cushion) of compressed gas in the storage to furnish the expulsive energy for the removal of the gas (working gas) desired to be withdrawn. Usually the cushion gas is natural gas already present in the selected reservoir or is that amount of injected gas left in the storage at the end of the withdrawal period prior to the following injection period. In many storage operations the cushion gas represents a large investment; consequently, the use of a relatively inexpensive inert gas is desirable. As mixing of the inert gas cushion with the stored natural gas is undesirable, the various mechanisms tending to bring about such mixing were the subjects of both theoretical and experimental studies.
L51975 Pressure Testing of Large Diameter Pipelines in Artic and Subartic Regions
Authors: Schultz
Published: August 2023

This study evaluates methods for pressure testing large diameter pipelines in arctic
and sub-arctic regions and recommends the most technically feasible method.
L51688 RSTRENG2 (DOS Version) User's Manual
Authors: Kiefner  , Vieth
Published: August 2023

The RSTRENG 3.0 (Windows Version) software program and users manual were developed to enhance the usability and options available in the original program RSTRENG. RSTRENG was developed as part of AGA PR-3-805, "A Modified Criterion for Evaluating the Remaining Strength of Corroded Pipe." Like the original version of RSTRENG, RSTRENG 3.0 can be used by pipeline operators to evaluate the remaining strength of corroded pipe. The required user inputs are pipe diameter, wall thickness, grade of the pipe material, and a series of pit depth and length measurements. The new version of the software actually produces the same results as the first version; the improvements serve to make the software more versatile and user-friendly. Includes soft-cover manual and software diskette (5 1/4-inch). (Includes: L51688B, Modified Criterion for Evaluating the Remaining Strength of Corroded Pipe).
L52239 Input to Code Revision for Interaction of Girth Weld Defects under Plastic Collapse Conditions
Authors: Denys  , Waele  , Lefevre
Published: August 2023

A pipeline girth weld may contain one single or multiple defects. If discrete multiple notches occur, current codes define by applying proximity rules the defect dimensions to be used in an ECA. The defect interaction rules contained in pipeline specific standards are based on linear elastic fracture mechanics with conservative approximations. Similar solutions for failure by plastic collapse are non-existent. In this study, using experimental data of wide plate tests, interaction criteria for ductile girth welds containing multiple coplanar surface breaking defects are proposed. Based on a simple plastic collapse assessment, defect length limits ensuring the onset of remote yielding in the pipe bodies are calculated. A two-tier assessment procedure, based on a comparison of the sum of the individual defect lengths with these characteristic limits, is proposed. If the total defect length is smaller than the characteristic defect length limit interaction will not occur. The defect length limit ensuring remote yielding in the case of multiple defects is dependent on the spacing between defects. The defect length limits also incorporate the effect of yield-to-tensile ratio. The performance behaviour of wide plates with coplanar surface-breaking defects is compared with existing and proposed interaction criteria. The assessment shows that the proposed defect interaction procedure is less conservative than the rules currently embodied in pipeline specific standards.
L52145 Geomechanical Analysis and Design Considerations for Thin-Bedded Salt Caverns
Authors: Olsen  , Wilson
Published: August 2023

he bedded salt formations located throughout the United States are layered and interspersed with non-salt materials such as anhydrite, shale, dolomite and limestone. The salt layers often contain significant impurities. GRI and DOE have initialized this research proposal in order to increase the gas storage capabilities by providing operators with improved geotechnical design and operating guidelines for thin bedded salt caverns.
Terralog has summarized the geologic conditions, pressure conditions and critical design factors that may lead to:

Fracture in heterogeneous materials;
Differential deformation and bedding plane slip;
Propagation of damage around single and multiple cavern;
Improved design recommendations for single and multiple cavern configurations in various bedded salt environments.

The existing caverns within both the Permian Basin Complex and the Michigan and Appalachian Basins are normally found between 300 m to 1,000 m (1,000 ft to 3,300 ft) depth depending on local geology and salt dissolution depth. Currently, active cavern operations are found in the Midland and Anadarko Basins within the Permian Basin Complex and in the Appalachian and Michigan Basins. The Palo Duro and Delaware Basins within the Permian Basin Complex also offer salt cavern development potential.

Terralog developed a number of numerical models for caverns located in thin bedded salt. A modified creep viscoplastic model has been developed and implemented in Flac3D to simulate the response of salt at the Permian, Michigan and Appalachian Basins. The formulation of the viscoplastic salt model, which is based on an empirical creep law developed for Waste Isolation Pilot Plant (WIPP) Program, is combined with the Drucker-Prager model to include the formation of damage and failure. The Permian salt lab test data provided by Pfeifle et al. 1983, are used to validate the assumptions made in the material model development.
For the actual cavern simulations two baseline models are developed for single and multiple caverns, respectively. Different parameters that affect damage propagation and deformation of salt cavern, such as cavern pressure, operating conditions, cavern height/diameter ratio, overburden stiffness and roof thickness are analyzed and the respective results summarized. For multiple horizontal caverns numerical models are developed to determine the cavern interaction and the minimum safe center to center distance.
A step by step methodology for operators to assess critical cavern design parameters for thin bedded salt formations is also presented.
L51508 Corrosion of the Annulus of Storage Wells
Authors: Kiefner  , Stulen
Published: August 2023

A study to determine the causes of corrosion in the annulus of storage wells. Is it a consequence of the aging process or completion method? What effect does cathodic protection and the atmosphere have on the problem?
NR199001A Current Status of Modeling Stress Corrosion Cracking of High Pressure Gas Transmission Pipelines
Authors: Parkins R.
Published: August 2023

The status of SCC modeling circa 1990.
NG-18-24-R02 Investigation of Stress-Corrosion Cracking in Buried Pipelines
Authors: Fessler Raymond , Berry W. , Elsea A. , Wenk R. , Reinoehl J.
Published: August 2023

A progress report summarizes the stress-corrosion-cracking phase of the NG-18 Program from its inception in 1965 through 1969.
NG-18-R25 The Effect of Tempering on the Mechanical Properties of Cold-Expanded Line-Pipe Steels
Authors: Groeneveld T. , Elsea A. , Grube K
Published: August 2023

Since the mid-1950's, a number of failures and leaks in cathodically protected line pipe have initiated in localized hard spots in the pipe wall formed by inadvertent quenching of localized areas of the pipe skelp on the runout table immediately after the final hot-rolling pass in the steel mill. Analysis of these failures indicated that cracks ultimately resulting in the ruptures or leaks, had initiated by hydrogen stress cracking (HSC).

During 1969, preliminary studies were conducted to determine (1) the feasibility of using localized tempering treatments to soften hard spots in line pipe to a level at which they would be insensitive to HSC under normal gas- transmission-pipeline operating conditions and (2) the influence of such treatments on the mechanical properties of the cold- expanded pipe steel. These studies indicated that tempering for 30 minutes at temperatures up to 1000 F did not reduce the yield strength of the X-52 base steel below those of untempered pipe. This effort evaluates tempering temperatures on the mechanical properties of X-52, X-60, and X-65 pipe.
PR-3-173-R01 Acoustic Emissions Testing of a 9.5-Kilometer Segments of the Moomba-Wilton Pipeline
Authors: Author Unknown
Published: August 2023

Describes the result of acoustic emission monitoring to detect stress corrosion cracking by the Pipelines Authority of South Australia. These tests took place on the 21st and 28th April, 1983.
PR-3-173-R02 Acoustic Emission Monitoring of 4.2-km Segment of the Moomba-Wilton Pipeline
Authors: Kiefner John
Published: August 2023

In the continuing effort to establish the viability of acoustic emission monitoring as a means of or as an aid to determining the integrity of a pipeline , a new opportunity to study the technique was afforded by a recent test conducted by The Pipeline Authority (TPA) in Australia on their Moomba-to-Wilton (MW) pipeline. This pipeline sustained a failure from stress corrosion cracking (SCC) in July of 1982 after six years of operation.TM has employed a multi-faceted approach to solving their potential SCC problem including the installation of ten kilometers of new pipe in one location. On one section of pipeline, however, they decided to utilize acoustic emission (AE) monitoring in conjunction with gas pressurization from the current maximum operating level of 5500 kpag (798 psig) to the maximum allowable operating pressure of 6900 kpag (1000 psig). The pressurization was to serve the dual purpose of providing some evidence that the pressure could be safely increased during the winter of 1983 and an overpressure needed for effective AE monitoring.
PR-15-NQ15-R01 Investigation on the Response of Orifice Meters to Pulsating Compressible Flow
Authors: Sparks Cecil
Published: August 2023

Evaluates the effects of orifice flow measurement errors in the presence of pulsating flows, specifically square root error. The work includes the development of an extended error theory, a series of tests was conducted at Southwest Research Institute to test the adequacy of this theory.
PR-3-921-R01 Impact on Pipeline Integrity Due to Crack Acceptance - Task2
Authors: Kiefner John , Ahmad J. , Scott P.
Published: August 2023

This study was undertaken on behalf of the National Energy Board to assess the implications for pipeline integrity of accepting cracks in girth welds and fillet welds around the ends of repair sleeves on the basis of an "engineering critical assessment' (ECA). The main focus was on the ECA methodology embodied in the Canadian Standards Association's Standard Z184, Appendix K. The current standard does not apply to cracks.
PR-3-722-R01 Acoustic Emissions Monitoring and Evaluation
Authors: Stulen Foster
Published: August 2023

Evaluates pipeline acoustic emission data gathered with the intent of detecting the development of pipe cracking. The primary objectives being to acquire data to verify the usefulness and accuracy of an analytical model of the acoustic emission process in buried pipelines an to demonstrate the capabilities of advanced analysis techniques.
PR-542-163745-R01 Defining Close Metal Object Detection Capabilities of MFL ILI Tools
Authors: Rau Jerry
Published: August 2023

There is a need to understand Magnetic Flux Leakage (MFL) in-line inspection data and determine if it distinguishes whether a Close Metal Object (CMO) is an adjacent pipeline or independent metallic article. There have been failures associated with CMOs both in contact and in close proximity with the pipeline, specifically water lines. With the knowledge gained on the sensitivity of MFL technology to detect such objects, a process could be developed to identify those CMOs which may be a hazard to the pipeline and prioritize them for evaluation.

This report has a related webinar.

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MH-2-95-R01 Public Inquiry Concerning Stress Corrosion Cracking on Canadian Oil and Gas Pipelines
Authors: Author Unknown
Published: August 2023

Data request and responses from the National Energy Board (Canada) regarding the direct and indirect costs associated with addressing stress corrosion cracking.

For reference only, not an official PRCI report.
L51501 Field Verification of Optimum Transducer Design Criteria for Acoustic Emission Monitoring
Authors: Sancar Selcuk , Stulen Foster
Published: August 2023

This work acquired and analyzed simulated acoustic emissions waveforms from pipelines in three series of field tests. The purposes of the analyses were to verify the accuracy of an analytical model of acoustic emission propagation in pipelines to determine transducer design/selection criteria, and to further evaluate the sensitivity of the verification system. Two sets of tests were performed on a bare and a coated 70-ft. long section of pipe. The third test was performed in conjunction with a hydrotest of a new line being installed near Clay City, Kentucky.
PR-4-172-R01 Modeling of Mixing in Porous Media
Authors: Foh Stephen , Poonawala N. , Pritchett J.
Published: August 2023

The objective of this work was to define potential problems for storage field operators who stored non-traditional (supplemental) gas supplies (imported LNG, synthetic natural gas, peakshaving gases, etc.) in reservoirs originally

using natural gas from traditional sources. Findings indicated that changes in storage field performance could be expected, including changed field inventory, deliverability and base gas requirements. The degree to which supplemental and traditional gases mix in storage reservoirs was identified as the key issue with respect to accounting for and dealing with these changes. The development of a reservoir simulator capable of handling gas-phase mixing in porous media was recommended. Such a model should account for mixing due to gravity segregation and hydrodynamic dispersion.
PR-015-133607-R01 Analyzing Active Corrosion in Inspection Data to Evaluate CP Criteria
Authors: Shukla Pavan , Nordquist Andrew , Pensado Osvaldo , Fisher Jay
Published: August 2023

The NACE-recommended cathodic protection (CP) criteria include -850 mVCSE on- and off-potential criteria, and 100 mV polarization potential. These criteria are widely used on underground buried structures such as oil and gas transmission pipelines to mitigate the risk of external corrosion. The objective of this work was to establish the effectiveness of cathodic protection criteria using field data from operational pipelines for variety of soil conditions and coating types. The recommendations included conducting several high-quality CIS runs during the ILI intervals, measuring coating quality and soil resistivity values, eliminating misalignment between ILI and CIS data using reference coordinates, and accounting for external corrosion where the root cause corrosion mechanisms would not relate to the level of CP.
PR-457-16200-R01 Control of Vented Methane Emissions from Integral Compressor Engines
Authors: Murray Trevor , Jacobs Timothy
Published: August 2023

At natural gas pipeline compressor stations, methane emissions from compressor and engine crankcases are often vented directly into the atmosphere. There may be advantages to capturing these emissions and using them to offset fuel usage and / or decrease the overall carbon footprint of such a typical compressor station. This study evaluates the feasibility of directing such captured emissions into the intake of the compressor engine and subsequently combusting the methane emissions into carbon dioxide and water. Although seemingly an obvious or trivial solution, there are in fact several challenges and issues that must be considered to evaluate if such a scheme is a reasonable course of action for compressor station methane emissions reduction. The study relies on both extensive literature review and model-based engine simulations to determine the feasibility of rebreathing crankcase gases in pursuit of reducing compressor station methane emissions. The conclusions of the study are limited to the crankcase vent rebreathing into the air intake of large bore, natural gas, 2-stroke engines.

The model-based engine simulations require detailed physical geometry of the subject engines as well as knowledge of basic engine operating parameters (e.g., fuel flow, air flow, and fuel composition). The simulation is based on the experimental facility located at Colorado State University, which is a 4-cylinder Cooper-Bessemer GMV-4. One of the important parameters needing to be known is the gas composition of both compressor and engine crankcases. It is extremely difficult to determine the composition of the engine crankcase gases, since the composition depends on a large variety of parameters. For this study, the gases from the compressor crankcase are modeled as methane (i.e., pipeline gas), and the gases from the engine crankcase are modeled as products of combustion with two different levels methane concentration (1500 ppm and 3000 ppm). A sensitivity analysis is performed, and the observed pressure traces from the model-based engine simulation show that the engine performance is not affected by the addition of rebreathed gases. This insensitivity mainly results from the very small rebreathed flow rates compared to the air intake, and the adjustments made on engine parameters, boost pressure and fuel injection rate, to keep trapped equivalence ratio (TER) and the energy delivery rate the same.
PR-312-17204-R02 Portable Analyzer Method Update - Phase 3
Authors: Coulson Wendy , McCarthy James
Published: August 2023

A multi-phase project has developed a simplified portable analyzer emission test method for measuring NOx and CO emissions from natural gas-fired combustion sources. The method leverages the inherent linear performance of electrochemical cell-based technology to provide simplified procedures that will lower cost. This Phase 3 report complements earlier Phase 1 and Phase 2 documents that established the technological basis (i.e., linear performance) of the simplified method, developed a draft method, identified data gaps associated method procedures, and conducted limited lab and field tests to address the data gaps. Those efforts culminate with the Phase 3 report that includes the revised test method, discussion of the key elements of the method, and the rationale for their inclusion. Key outcomes are discussed, including advantages to users and to the quality of the measurement. For example, modification of the NO2 pre-check sequence and calibration gas concentration will have significant impacts on the quality of the NO2 calibration gas as manufactured, and the consistency of the measurement of the species. Plans are discussed for final phase tasks associated with sharing the method with EPA or state agencies and pursuing acceptance. .
PR-306-123733-R01 Realistic Dent and Gouge Defects With and Without Fatigue Cracks
Authors: Batisse Remi , Zarea Mures
Published: August 2023

This report provides basic information about vintage pipe samples containing dent and gouge defects with and without fatigue cracks for inspection technology evaluation and repair techniques qualification. Four mechanical damage dent and gouge defects without fatigue cracks were created in a realistic manner in vintage pipes. The two remaining samples containing also the same types of defects were submitted to internal pressure cycling to initiate a significant crack at the bottom of the gouge. Two types of defects were created: intermediate gouge in shallow dent, intermediate gouge in severe dent. Four defects are dedicated for performance evaluation of inspection technologies whereas two defects (one of each type) without fatigue crack are for repair techniques qualification. These defects are similar to those created in project PRCI MD-4-6 for destructive metallurgical characterization and for burst and fatigue tests.

This version of the report does not contain results of any measurements performed on the defects, in order to facilitate blind testing of inspection technologies using the samples produced in this project.
PR244-173902-R01 On-water Leak Detection System Evaluation
Authors: Apps Christopher , Johnson Tyler
Published: August 2023

The hydrocarbon industry is directing efforts towards reducing the environmental impact of operation through improving pipeline performance and addressing evolving regulatory requirements. As a result, many different external leak detection technologies have been recently developed; however, it is challenging to test these systems with real hydrocarbon products. The research project described herein evaluated the performance of six external leak detection systems intended to identify the presence of hydrocarbon products on the surface of water. The scope was limited to an idealized freshwater environment. Tests were conducted with five hydrocarbon test fluids (gasoline, diesel, Synthetic Sweet Blend, Access Western Blend and Cold Lake Blend) along with three additional test fluids (canola oil, salt water and motor oil). Canola oil was considered as a candidate surrogate fluid and salt water as a possible source of false alarms, while motor oil was considered as a candidate surrogate fluid or a false alarm trigger, depending on the field application. Testing was performed by releasing each test fluid onto the surface of a water basin with six sensors located equidistant from the release point. Each sensor's response to contact with the test fluid was monitored and compared based on time to detection and estimated slick thickness at detection.
PR-244-153719-R01 Quantification of ILI Sizing Uncertainties and Improving Correction Factors
Authors: Koduru Smitha , Skow Jason
Published: August 2023

Operators routinely perform verification digs to assess whether an inline inspection (ILI) tool meets the performance specified by the ILI vendors. Characterizing the actual ILI tool performance using available field and ILI data is a difficult problem due to uncertainties associated with measurements and geometric classification of features. The focus of this project is to use existing ILI and excavation data to develop better approaches for assessing ILI tool performance.

For corrosion features, operators are primarily interested in quantifying magnetic flux leakage (MFL) ILI tool sizing error and its relationship to burst pressure estimates. In previously completed PRCI research, a limited MFL ILI dataset was used to determine the corrosion feature depth sizing bias and random error using principles published in API 1163 (2013). The research demonstrated the tendency for ILI predictions to be slightly lower than field measurements (i.e., under-call) for the dataset studied, and it provided a framework for characterizing this bias.

The goal of this project was to expand on previous work by increasing the number and type of feature morphologies available for analysis, and by estimating the sizing error of ILI measured external corrosion features. New geometric classification criteria, complementing the current criteria suggested by the Pipeline Operator Forum (POF 2009), were also investigated. Lastly, correction factors based on burst pressure prediction accuracy were developed to account for the effect of adopting various feature interaction rules.

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PR-306-123732-R01 Realistic Dent and Cracked Gouge Defects for Characterizing Inspection Tool Performance
Authors: Batisse Remi , Zarea Mures
Published: August 2023

This report provides basic information about modern pipe samples containing dent and cracked gouge defects for performance evaluation of inspection technologies. Five mechanical damage dent and gouge defects were created in a realistic manner in modern pipes and then submitted to internal pressure cycling to initiate a significant crack at the gouge bottom. Three types of defects were created: shallow gouge in shallow dent, severe gouge in shallow dent and shallow gouge in severe dent. All defects are planned to be used to performance evaluation of inspection technologies. These defects are similar to those created in project PRCI MD-4-1 for destructive metallurgical characterization and for burst and fatigue tests.

This version of the report does not contain results of any measurements performed on the defects, in order to facilitate blind testing of inspection technologies using the samples produced in this project.
PR-244-15700-R01 Characterization of 4.5 Inch Casing Corrosion Features
Authors: Tao Gang
Published: August 2023

This work conducts a measurement and analysis project on of 4.5" casing corrosion features. Casing samples removed from natural gas storage wells were provided for corrosion feature characterization and comparison in this project. These casing samples have been previously logged by Baker Hughes using their 4995 High Resolution Vertilog (HRVRT) Magnetic Flux Leakage (MFL) tool in 2013. The log results were also provided to C-FER, which formed the basis for comparing to laboratory-measured corrosion features to assess the HRVRT performance.

Two measurement methods, the Internal Rotary Inspection System (IRIS) and Ultrasonic Testing (UT), were tried to characterize the casing corrosion features. The IRIS was unsuccessful, and the UT results were used in the subsequent feature comparison analysis with the MFL logs. However, due to the poor quality of the UT measurements, there was little confidence in the accuracy of the assessment of the MFL tool measurement error. A decision was therefore made by PRCI to halt this project. This report summarizes the work performed and the results.
PR-186-163606-R01 Establishing the Potential Severity of Various Cathodic Protection Shielding Parameters
Authors: Kowalski Angel
Published: August 2023

A semi-quantitative scoring protocol was developed to identify pipeline systems with the highest relative susceptibility to coating CP shielding. The scoring protocol takes into consideration the type of coatings, surface preparation, types of soils, weather conditions and pipeline characteristics. The protocol was tested over pipeline cases provided by pipeline operators. The users are encouraged to use the scoring protocol to screen, prioritize pipeline systems susceptible to coating CP shielding, and collect critical data in order to improve the performance of the tool with the goal to minimize the impact of this threat on the integrity of their pipelines. Guidelines have been provided to help the users of the protocol improve the monitoring, inspection and mitigation of external metal loss due to coating CP shielding.
PR-186-163603-R01 Polarization Criteria for Mitigating Corrosion on High-pH SCC Susceptible Pipelines
Authors: Chawla Sandeep , Beavers John , Sridhar Narasi
Published: August 2023

For pipelines that are potentially conducive to high-pH stress corrosion cracking (SCC), the cathodic protection (CP) criterion most typically used is based on a polarized potential of -850 mV versus the Saturated Cu/CuSO4 electrode (CSE). Since this criterion is difficult to meet on pipelines that have deteriorated coatings, alternate CP criteria need to be established.

This research was directed at assessing the feasibility of a polarization-shift based CP criterion for mitigating corrosion on high-pH SCC in pipelines, and providing a technical basis for its further evaluation and adoption in the field. The 100-millivolt (mV) polarization (or polarization shift) criterion is most commonly used on poorly coated or bare structures where it is difficult or costly to achieve either of the -850-mV criterion. In many cases, 100 mV of polarization can be achieved where the off potential is less negative than -850 mV (CSE). The polarization shift criterion has several advantages including lowering the cost of protecting pipelines with deteriorated coatings, minimizing coating degradation, and minimizing hydrogen embrittlement.
PR-328-173802-R01 Hard Spot NDE Evaluation
Authors: Krishna Shree , Krishnamurthy Ravi
Published: August 2023

The presence of hard spot in pipelines, a localized confined region of relatively higher hardness, are prone to crack initiation and hydrogen embrittlement. Early detection of hard spots before it can be an integrity threat is an essential part of integrity management plan for pipelines susceptible to hard spot related failures. Electromagnetic principles and its dependence on the microstructure, heat treatment and chemistry are used effectively for hard spots characterization. The ability to detect shallow hard spots is essential for thermo-mechanically heat treated steel. It is unclear whether there are commercial tools that are effective, and no quantitative data is available. A holistic review of the existing and emerging technologies and their theoretical basis for the hard spot detection and their applicability to pipelines is indeed needed. This work reviews the electromagnetic principles that are applicable for hard spot detection/discrimination, and the applicable technologies that are either developed or being developed by various global NDE suppliers. Four different technologies have been identified for further examination during Phase II. The intent would be to quantify the detection/discrimination and characterization capabilities of each of these technologies. Selected providers have a unique way of hard spot identification and it would be very beneficial to compare their performance in the phase-II of this project. Inspection approaches, their key principles and their latest development are presented in this report.
PR-000-18COMP-R01 Gas Engine Emissions Compendium
Authors: Choquette Gary
Published: August 2023

The PRCI Technical Committees have carried out many research projects related to the subject of natural gas fueled engine emissions. This report, therefore, presents a summary of past PRCI funded studies in the area of Gas Engine Emissions. Since studies sponsored by other industry groups (e.g., INGAA, EPRG, APIA, CEPA, etc.) or by individual pipeline companies are not included, this report does not represent a review of the topic in the broader industry-wide sense. Instead, it is designed to provide a guide to past work so that current TC members can identify and locate project reports that might be of use in addressing their current day-to-day Gas Engine Emissions issues.
PR-575-183603-R01 Performance of External Profiling Inspection
Authors: Kimble Tyron
Published: August 2023

Previous efforts have shown that the laser/light based NDE systems do generally provide sufficiently accurate measurements for validating MFL ILI. However, the specific samples studied lack metrics associated with large metal loss areas or areas of interacting metal loss. It is generally accepted that the performance would deteriorate in such conditions, but a comprehensive evaluation has not been performed. This project aims to provide an insight into the performance of these technologies as pertaining to the measurement of larger or interacting areas of metal loss on pipelines.