Overall Measurement Accuracy
Author(s): L. K. Bryant
Abstract/Introduction:
Websters Ninth New Collegiate Dictionary defines accuracy as: 1: Freedom from mistake or error: correctness 2a: conformity to truth or to a standard or mode: exactness b: degree of conformity of a measure to a standard as a true value. Accuracy is an interesting word in the gas industry and in particularly in the world of gas measurement. The quest we all seek to obtain is the perfect cubic foot. To seek that perfect cubic foot of natural gas we must begin with a standard. A standard is something accepted as the norm or model for the industry, as a starting point. The standard for the gas industry in orifice measurement is the AGA Report No, 3 and No. 8. In positive and displacement measurement it is the AGA Report No. 7.
Go to Download Page
Email Reference
Document ID:
B3BA11FE
Operations Of On-Line Chromatography Methods, Installation, Operation And Maintenance
Author(s): Paul E. Kizer
Abstract/Introduction:
Gas chromatography is today being chosen more and more in the natural gas industry for on line monitoring of gas quality because the calculations of the gas volumes in modem electronic flow meters requires not only BTU information, but specific gravity, Mol % CO2 and Mol % N2 as weU. The current AGA-8 super compressibility equations also require methane concentration for the gross method and a complete analysis for the detailed method of calculation of Fpy. Most natural gas custody transfer contracts use MMBTU rather than MCF as the accounting units of gas transfer today. Also, modem micro-packed columns are providing faster cycle times for critical BTU measurement applications. For all these reasons mentioned above, and the fact that the installation requirements for chromatographs are less stringent than calorimetric methods, the use of gas chromatographs is quickly becoming standard practice.
Go to Download Page
Email Reference
Document ID:
82BA5C9B
Unaccounted-For Gas
Author(s): Mike Haydell
Abstract/Introduction:
Unaccounted-for gas can be defined as the difference between the amount of gas purchased and the amount of gas sold through a measured gas distribution system. This difference is commonly described as a percentage of gas purchased: PERCENT UNACCOUNTED-FOR GAS.
Go to Download Page
Email Reference
Document ID:
3F88484C
Influence Of The Latest Revision Of Ansi 2530 (AGA #3) On Flow Cohpitter Software
Author(s): Raymond G. Teyssandier
Abstract/Introduction:
The new American Petroleum Institute, American Gas Association, Gas Processors Association orifice metering standard represents the first major change in the USA calculation procedures published since 1935. As almost all of the approximately 19 trillion cubic feet of natural gas in the US passes through orifice meters this standard will have a significant impact. This new standard will result in a not only in different, but also more accurate, volumes then those calculated by all previous USA or international standards. The changes that were made to reach these improvements were all based on the latest available data that had been gathered by various US and European researchers. The new orifice measurement standard is written in four parts to separate the text to facilitate use and simplify updating when changes are needed. The sections are:
Go to Download Page
Email Reference
Document ID:
1014FDE2
Meter Shop Equipment And Operations
Author(s): Jon T. Payne
Abstract/Introduction:
The meter test and repair function is an essential element of the gas distribution industry. The role of the meter shop in the typical distribution company has undergone revision, driven primarily by changing economic and technological factors. For most of the 1980s, rising labor costs and low efficiencies compelled many distribution organizations to curtail meter repair operations. One school of thought viewed the residential gas meter as evolving into a disposable item. As new technology and modem automation techniques have been applied to the meter shop, this trend has been reversed in recent years. A renewed interest in meter lest and repair operations has resulted in modernization of several meter shop facilities across the country. The concept of a comprehensive meter test and repair facility appears to be resurgent among many organizations.
Go to Download Page
Email Reference
Document ID:
C50AA9EC
Carbon Dioxide Detection In Natural Gas Pipeline Systems
Author(s): Maurice Barnes, Jr.
Abstract/Introduction:
Carbon Dioxide (CO2) detection and monitoring capability is desirable in pipeline operations downstream of Amine treating plants or in other locations where CO2 concentrations have the potential of exceeding contract or operational specifications. The scope of this paper is to evaluate the effects of Carbon Dioxide on pipeline operations, to provide a basis for evaluating design and operating requirements of continuous CO2 monitoring instrumentation, and to examine the theory behind infrared spectroscopy analysis.
Go to Download Page
Email Reference
Document ID:
D447B9FA
New Ideas In Measurement Real-Time A Measurement Perspective
Author(s): R. C. Leitschuh, Jr.
Abstract/Introduction:
The environment of the natural gas industry is changing. The state of the industry is in tremendous flux concerning the handling of natural gas business, both physically and contractually. To adapt, it is imperative that we step forward to the challenge ahead of us. That challenge is to be a major contributor to the success of becoming an ideal pipeline operat ing system. As progressive pipeline companies confront the challenges of todays demanding and competitive environment, trends will continue to develop in the quest for the ideal pipeline operating systems. The ideal pipeline operating system might take on one of several scenarios, however of premium importance is its ability to adapt to change. The most common of these strategies is the concept of Real-Time. This concept however has lead many companies to grapple with the methodologies and issues which arise through implementation and conversion while striving for this innovative, operating philosophy. Those companies which most nearly approach a highly integrated , coordinated and efficient Real-Time system will most certainly command a competitive advantage.
Go to Download Page
Email Reference
Document ID:
F967505A
Communication Between Office And Field
Author(s): Duane A. Harris
Abstract/Introduction:
Todays gas industry is constantly changing, with increasing demands on office and field personnel. To meet these demands requires timely communication between the office and field employees. Both of these locations (field and office) have been impacted with increased work loads and constant upgrades in equipment and software. With all of this happening, it is very easy to overlook one of the key links to accurate measurement - communication. By the time that a gas day has started at the meter site on a chart or an RTU until the volume has been calculated or verified in the ofUce, 1 to 30 days may have elapsed with as many as 8 to 10 people handling each individual volume record. With this many people involved covering that span of time, communication becomes a vital part of the measurement process.
Go to Download Page
Email Reference
Document ID:
CA2FC4A7
API 14.3/AGA 3 Mechanical Specifications: Old Vs. New
Author(s): Kenneth E. Embry
Abstract/Introduction:
The most widely accepted means of measurement of natural gas and other fluids is the Orifice Meter. The primary elements of the orifice meter include the orificeplate, orifice fitting orflanges, adjacent piping and flow conditioner or straightening vanes which make up the meter tube. The criteria for design, manufacture and application of orifice meters has existed for many years, but with limited support data. Recent studies from the United States and Europe have proven standards for orifice meters to be inadequate to achieve the degree of accuracy required.
Go to Download Page
Email Reference
Document ID:
C702EB7E
Training Fiklp Measurement Personnel
Author(s): E.D. Woomer, Jr.
Abstract/Introduction:
A practical, meaningful, and comprehensive training program in an appropriate learning environment is essential to fully develop the human resource.(1) This statement is particularly applicable to field measurement personnel in the natural gas industry. Natural gas measurement is a very specialized and technical field and todays measurement technician must have a broader and more detailed knowledge of a vast variety of equipment. Comprehensive training of field measurement personnel becomes of paramount importance.
Go to Download Page
Email Reference
Document ID:
EAC1CC04
Orifice Recorder Testing
Author(s): John D. Utter
Abstract/Introduction:
Orifice recorder testing plays a vital role in an attempt to account for a volume of gas having passed through a metering point. Without reliable recordings, efforts to accurately measure gas volumes will be hindered, and may create a domino effect on field balances as well as monetary disbursements to the companies, investors, and royalty owners involved. The frequency at which testing is to be performed may vary from station to station due to contractual stipulations,company policies, volume of gas passing, or any time that a meter is thought to be recording in error.
Go to Download Page
Email Reference
Document ID:
5E12D89F
Spot Sampling Techniques
Author(s): Jerry Bernos
Abstract/Introduction:
In 1978 the United States Congress passed the Natural Gas Policy Act. This legislation required that natural gas be priced according to its energy content rather than by volume alone. At the same time, the economics of the natural gas industry caused natural gas prices to soar. These two factors resulted in a vast increase in the demand for accurate analyses of natural gas systems. Since it was not economically feasible to place analytical instruments at each and every location requiring BTU determinations, a corresponding increase occurred in the need to obtain spot samples of these systems. This paper is intended to present the problems that arise in spot sampling and to introduce the industry accepted methods which can overcome these problems.
Go to Download Page
Email Reference
Document ID:
7CE8D6FD
Fundamentals Of Natural Gas Chemistry
Author(s): Jerry Bernos
Abstract/Introduction:
At the thought of having to study and learn chemistry, most individuals feel that the subject is far to complex to be within the realm of their understanding. NOT SO! Just as a person does not have to be an auto mechanic to drive a car, one does not have to be a graduate chemist to learn a few basic chemical concepts. This presentation will not turn you into a trained chemist. It should, however, give you a very basic and simplified understanding of the nature of the materials that we are required to deal with on an ongoing, everday basis.
Go to Download Page
Email Reference
Document ID:
A6030909
Pipeline Moisture Measurement
Author(s): Jeff Moon
Abstract/Introduction:
The moisture content in pipeline natural gas is one of the many parameters that must be monitored as a part of controlling the quality of the gas. Other parameters that are monitored include gas composition, heating value, and relative density (specific gravity). The moisture content in natural gas will vary for a variety of reasons. There are various methods used to control the moisture in the gas and there are also different Instrument types used to measure the moisture content. In this article, we will discuss the measurement methods and we will present general guidelines for the use of typical moisture measurement instruments.
Go to Download Page
Email Reference
Document ID:
748407A5
Economics Of Electronic Measurement
Author(s): Harry J. Workmen
Abstract/Introduction:
During the last 10 years, gas measurement has gone through a period of incredible change. Since the early 1900s, mechanical recorders have dominated the gas measurement industry but, since 1985, the advent of low powered flow computers has been changing the way we do business in the gas industry. There are over 50,000 flow computers in daily operation in the United States from a variety of manufacturers. This fundamental change in a basic process has produced impacts on the economics of the gas industry in several areas. This paper will not attempt to walk you through economic calculations since the variables are many and vary from company-tocompany , depending upon your individual needs. Instead, we will look at three primary areas that are impacted by the decision to use electronic flow measurement (EFM) . These areas are: field operations, measurement office and computing.
Go to Download Page
Email Reference
Document ID:
EC3D96DF
Measurement Of Energy Content In A Gas
Author(s): Ashu K. Gupta, Bill Bonett
Abstract/Introduction:
In the natural gas industry, the monitoring of energy content has become of paramount importance. During custody transfer and for biUing purposes, accurate, reliable, and continuous monitoring of the energy content of the gas is a necessity. This measurement may be obtained from two different types of instruments: Ones that measure the energy content directly, and others that do it indirectly. A calorimeter measures this value directly whereas a gas chromatograph (GC) measures it indirectly. The oldest and most trusted calorimeter has been the Cutler-Hammer calorimeter. Changing requirements and needs have permitted other techniques to come to the forefront. These new calorimeters provide faster measurement of the BTU/SCF of the incoming gas. Chief among these are the following: The TruTherm Q, the FLOCAL Calorimeter, and the Cosa Calorimeter. The GC is the only significant instrument in the indirect measurement arena.
Go to Download Page
Email Reference
Document ID:
63A66247
Pulsation Effect On Gas Turbine Meter Measurement
Author(s): Winston F. Z. Lee
Abstract/Introduction:
In a number of gas flow measurement applications (e.g., gas production fields, ccnpressor stations, pulsation induced by regulators) , the flow may not be steady, but pulsating. Pulsating flow may cause error in flow measurement by a turbine meter. Frequently, this can be rectified by placing the meter further fran the source or by adding a pulsation daitpener, but sometimes this is not possible. Ihus, it may be important to know vtfther the magnitude of the error due to pulsating flow condition is significant.
Go to Download Page
Email Reference
Document ID:
5A5E570D
Electronic Equipment Classification In Hazardous Location
Author(s): F. A. Tajani
Abstract/Introduction:
The purpose of this paper is to help understand and meet NEC recommendations for electronic equipment classifications in hazardous locations. The paper will also focus on and illustrate the adequate ventilation and procedure involved in using non-classified tools in classified locations. The gas utility areas to which this paper applies are areas surrounding the piping system, which include valves, flanges, fittings, meter tubes, meter buildings, etc.
Go to Download Page
Email Reference
Document ID:
AFC244B1
Odorization
Author(s): G. m. Johnson
Abstract/Introduction:
Odorization in the United States is separated into two basic groups. Liquified Petroleum Gas (LPG) Odorization and Natural Gas Odori2tion. Ethyl MercapCan is used as the odorant for LPGs. Natural Gas Odorants are generally a blend of two or more components with the occasional exception of Thiophane. It is important for each odorant user to first determine their odorization objective or goal. Odorant blend selection along with compatibility to equipment and gas composition is the next important factor in determining your odorization requirements. This paper will give you a basic outline of the major components and blends in use today.
Go to Download Page
Email Reference
Document ID:
81BEC7C9
Design Considerations For Orifice Meter Tubes
Author(s): Kyle Barry
Abstract/Introduction:
Orifice meter tubes, the most widely used equipment for measurement of natural gas fluids, has strict design requirements that must be followed to insure the accuracy stated in the Manual of Petroleum Measurement Standards, Chapter 14, Section 3. This standard has been approved by the American National Standards Institute, American Petroleum Institute, American Gas Association, and Gas Processors Association. These standards will be herein referred to as API 14.3. This paper will discuss the design requirements of the orifice fitting, its operation, and the fabrication requirements of the meter tube. One of the first decisions that must be made in designing a meter tube is what type orifice plate holder to use. There are three tjpes of plate holders to choose from: orifice flange unions, single chamber fittings, and dual chamber fittings.
Go to Download Page
Email Reference
Document ID:
879829CF
The First Winters Success And More Changes To Come
Author(s): Charles B. Cline
Abstract/Introduction:
The Federal Energy Regulatory Commission (FERC) issued the final Order 636 in April 1992, It contained directives on many issues facing the natural gas industry but there were 10 key elements (see Table 1) that defined the framework for a new, more market responsive way to deliver gas to consumers. Interstate pipelines were required to implement the order prior to the 1993-1994 winter heating season. Many concerns were voiced about reliability of service, availability of supply, and additional costs to the consumer. Unknown in the fall of 1993, the first heating season was to be a challenge for the industry. Success could lead to continuing deregulation. Failure could result in a political firestorm of new regulations.
Go to Download Page
Email Reference
Document ID:
B4120ED7
Chart Editing And Integration Methods To Reduce Errors And Obtain Accurate Gas Volumes
Author(s): Gary R Menzel
Abstract/Introduction:
The title assigned to us for this presentation may imply that we can define specific means to reduce errors and thereby improve measurement accuracy Certainly we hope that our observations may contribute to that purpose but there is something unique about each companies operations which prevents the application of a single procedural formula to everyone. A substantial part of our business is auditing gas purchasers, and we believe the statistics obtained in that process provide a representative cross section of the kinds of errors experienced by most chart departments. Defining a problem may be the first step toward its resolution, and it is that which we shall address in this report.
Go to Download Page
Email Reference
Document ID:
AFD43636
Electronlc Flow Meter Auditing
Author(s): Gary P. Mcnzel
Abstract/Introduction:
As Electronic Gas Meters (EGM ) replace the more traditional chart recorders as the method of recording and calculating custody transfer volumes in the natural gas industry, it becomes more and more important to be able to audit the volumes produced by these devices Our company has been doing some audits on electronic flow meters since 1984 and currently audit over 30 different pipelines at EGM custody transfer stations. Over the twelve month period ending December, 1992, we found errors on over 3% of all of these stations audited which were resolved by agreement between the parties involved. The incidence of error on the EGM stations we audit falls in the same range as that of the chart recorder stations audited. i We have summarized the types of errors we have found in EGM auditing and these results are listed in table one. Where a category is listed as .00%, it is an error which has occurred in the past but that did not occur in during the twenty four month period included in the table. Where possible, we have kept the same code numbers as wc use to classify errors found in chart auditing, though in fact the location where many of these occur has moved from the office to the field.
Go to Download Page
Email Reference
Document ID:
0788FD83
Mechanical Vs. Electronic Correcting Devices
Author(s): Charles Guzowski
Abstract/Introduction:
Metering devices such as displacement meters and inferential meters measure gas at line conditions. Since gas is a compressible fluid it responds to changes in pressure and temperature. The gas meter then should be capable of accounting for these varying line conditions. Since the 1930s meter have been mounted with mechanical instruments which correct for metered gas volume with varying line conditions- A change in line conditions, be it pressure or temperature, change the position of linkages within the instrument. The linkage changes give the instrument the capability to vary the speed of the correc t volume counter to a given base standard volume. The most common base standard for a cubic foot is considered to be a measured volume at a temperature of 60F and a pressure of 14,73 psia. Mechanical instruments have been, for many years, meeting the gas industrys need for metered volume correction although, in the 1970 s the advancements in microprocessor technology gave way to the design of electronic base volume computers. The electronic correctors have the capability to compensate for pressure and temperature changes but also have additional capabilities not found with mechanical devices.
Go to Download Page
Email Reference
Document ID:
68D25C2B
Computer Applications In Chart Processing
Author(s): Russel W. Treat
Abstract/Introduction:
The natural gas business has been imdergoing an incredible amount of change in recent years, and the gas measurement department has not been exempt Significant changes in regulation and market dynamics continues to drive much of this change. At the same time, newer, less expensive, more flexible and more powerful computer systems are enabling companies to adapt and make necessary changes. As the cost of computing continue to fall, and as systems offer more performance and flexibility, we can expect that the only constant will be constant change.
Go to Download Page
Email Reference
Document ID:
717936E8
A.G.A. Report No. 8 And Its Effect
Author(s): Kenneth E. Starling
Abstract/Introduction:
The natural gas industry is currently implementing extensive changes in orifice flow calculations for natural gases. The technical basis for these calculations is provided by the results of cooperative worldwide research carried out in recent years. The technical documentation for the calculation methods appears in the most recent versions (1992) of American Gas Association (A.G.A.) Report No. 3, Orifice Metering of Natural Gas and Other Related Hydrocarbon Fluids and No. 8, Compressibility Factors of Natural Gas and Other Related Hydrocarbon Gases, and Chapter 14 of the American Petroleum Institute (API) Manual of Petroleum Measurement Standards. It should be noted diat Section 2 of Chapter 14 of API MPMS is equivalent to A.G.A. Report No. 8 (Reference 1). Also, it should be noted that the following are equivalent documents: (I) Section 3 of Chapter 14 of API MPMS, (2) A.G.A. Report No. 3, (3) GPA 8185, (4) API 2530 and (5) ANSI/API 2530 (Reference 2). This presentation discusses A.G.A. Report No. 8 and its effect with regard to natural gas flow measurement and related matters. The following topics are discussed.
Go to Download Page
Email Reference
Document ID:
345E6E44
Portable Gas Chromatograph Methods, Installation, Operation, Maintenance
Author(s): Louis N. Cox
Abstract/Introduction:
The methods used in determining BTU content of natural gas varies from on-line analysis to collection of samples in cylinder and transporting to laboratories for analysis. The on-line analysis are used on custody transfer applications and measurement to large users of natural gas. The sample cylinders are from auto-samplers, spot samples and well head samples. The time factor is of great concern to the gas suppliers - the period of time of sample to results. The on-site analysis using high speed portable chromatographs reduces this time factor to same day results.
Go to Download Page
Email Reference
Document ID:
A04E7D9B
Techniques Of Gas Sampling
Author(s): Thomas F. Welker
Abstract/Introduction:
This paper will cover the philosophy, importance, and techniques involved in sampling Natural Gas to ensure the collected sample is representative of the gas stream and is repeatable.
Go to Download Page
Email Reference
Document ID:
627F9E05
Fundamentals Of Positive Displacement Diaphragm Meters
Author(s): Brian Stack
Abstract/Introduction:
During the eariy 1800s when gas was being manufactured from coal the need arose to be abUe to accurately measure gas usage and therefore charge the customer for only the actual amount of gas that they had consumed. This was originally completed through the use of a wet type drum meter invented by Samuel Clegg in 1815. The wet type was improved in 1825 by John Malam and Samuel Crosely, however due to problems such as freezing, large size, and high costs an alternative was needed. In 1843 the alternative was developed by an Englishman by the name of Thomas Glover. Glovers invention , the dry displacement diaphragm meter, has since become the industry preference for measuring gas usage. The original Glover meter consisted of 2 diaphragms and a sliding valve with linkages connecting the two.
Go to Download Page
Email Reference
Document ID:
FD5E8E01
Fundamentals Of Rotary Metering
Author(s): Peter Walker
Abstract/Introduction:
In North America, almost all natural gas is measured by four types of meters diaphragm, rotary, turbine and orifice. Diaphram and rotary meters are classified as positive displacement meters, indicating, they alternately fill and empty measurement chambers of a fixed, known volume. Rotary meters have been in use for over sixty years in the gas industry. During the early years rotary meters were constructed of cast iron which made them guite heavy. In the past twenty years, rotary meters have been constructed of lightweight aluminum alloys, allowing them to be easily line mounted, The two principal manufacturers of rotary meters in the North American market are Romet Limited and Dresser Industries. In the world market, there are several other companies supplying rotary meters, including Instromet and Schlumberger.
Go to Download Page
Email Reference
Document ID:
6A75875E
Effects On Entrained Liquid On Orifice Measurement
Author(s): C. V. Mooney
Abstract/Introduction:
In the measurement of natural gas in field operations using the conventional orifice meter, all of the factors used in the calculation of flov are based on the assumption that the gas is dry. This condition is rarely the case in field measurements. The A.G.A. Committee Report No. 3, (l), does not give any information or data regarding the effect water and/or distillate may have upon gas measurement by the orifice meter. It was in this area of gas measurement that graduate-engineering students at Texas A&I University, Kingsville, Texas have conducted research operation in the laboratory and in the field.
Go to Download Page
Email Reference
Document ID:
EDCD6DAC
Operation Of Orifice Meter Chart Integrator
Author(s): Gary Hammond
Abstract/Introduction:
The UGC Chart Processor is a microprocessor based system designed to translate orifice meter chart records into accurate billing-compatible data of integrated flow (chart extension), flow time and average pressure. It will handle American Westcott and Foxboro) charts as the pens can be mounted so as to pivot in the same geometric paths as the recording pens of these types of meters. As an option, the Chart Processor can be fitted with pen mounts for Taylor and/or Rockwell charts. The operator directs the pens to follow the records by moving the trace handles as the chart rotates. The rotational speed of the chart table is governed by a variable foot control. The chart is secured to the chart table so its rotation and the motion of the pens by the operator simulate the actions in the recording meter.
Go to Download Page
Email Reference
Document ID:
4B80385A
Meter Selection For Various Load Requirements
Author(s): Anthony A. Schneemann
Abstract/Introduction:
As gas prices and cost of equipment rise, the measurement of the product will increase in importance and it will be up to the measurement engineer to design the most efficient and economical meter station possible after all, the gas meter is known as the Cash Register of our business.
Go to Download Page
Email Reference
Document ID:
F279AAF7
Handling Hazardous Materials Related To Measurement
Author(s): Lanny W. Cargile
Abstract/Introduction:
Anyone involved with natural gas measurement has surely had occasions when handling hazardous material was necessary. Knowing how to properly handle these materials has not always been an easy task. Here we will look at some of the regulations and other guidelines that address the handling of hazardous materials and where to obtain information on handling specific hazardous materials.
Go to Download Page
Email Reference
Document ID:
FC1064C2
Hydrogen Sulfide Detectors And Determination
Abstract/Introduction:
Hydrogen sulfide is measured in the natural gas industry for three main reasons: l)personaI safety 2)corrosion control and 3)contractual obligations.
Go to Download Page
Email Reference
Document ID:
E2CDFE71
Field Experience With Electronic Calibrators
Author(s): Claude A. Winslow
Abstract/Introduction:
The use of electronic pressure calibrators in the gas industry has added new concerns and issues in pressure measurement. With the onset of electronics, new and strange words began appearing. Readings appeared that perhaps didnt match the old reliable standby calibration methods. Terms like sensitivity, accuracy, resolution, traceable standards, and correction factors gave the technicians a challenge when performing their calibrations. One can add to this already complicated list, the effects that temperature has on the test instrument and how that effects the accuracy of gas measurement. When using electronic pressure calibrators, technicians will be ahead to look carefully for an instrument that is traceable, precise, accurate, sensitive, and repeatable.
Go to Download Page
Email Reference
Document ID:
3713D994
D.O.T. Mandated Training
Author(s): Jim Gorman
Abstract/Introduction:
Training is nothing new to our industry. It has been around for as long as Gas has been sold commercially. So why all the concern over mandated training? Probably fear of the unknown is our highest hurdle too clear. Currently, D.O.T. Mandated Training is only proposed and not in print. Yet reliable sources still say its only a matter of time before the Rule making is made.
Go to Download Page
Email Reference
Document ID:
115A507E
Report On API Egm Standard
Author(s): Brent E. Berry
Abstract/Introduction:
Since this report references both itself and the 21.1 standard, the following nomenclature has been adopted to make it clear which document is being referenced. report - references this document, the one you are now reading. standard references the 21.1 standard, unless otherwise noted. section and subsection both refer to portions of the API 21.1 standard. document is a generic term that could be referencing either document. Hopefully the context will make it clear which document is being referenced.
Go to Download Page
Email Reference
Document ID:
7B44F099
Pulsation Reduction By Acoustic Filters For Metering Applications
Author(s): Larry E. Blodgett, Robert J. Mckee
Abstract/Introduction:
Because of the adverse effects of pulsations on orifice and other types of flow meters there is for many installations, a need to eliminate or decrease the amplitude of pulsations in the piping. This task has been the primary domain of acoustical piping designers who have had both theoretical and practical field experience in such areas. The most common and effective treatment for pulsation control is the design and installation of acoustic fillers. However, most filters designed by novices are not effective and are costly to operate because of pressure drop losses. This paper discusses the basic principles and considerations in acoustic filter design.
Go to Download Page
Email Reference
Document ID:
59AEE0C6
Field Testing Of High Volume Gas Turbine Meters
Author(s): Jim Beeson
Abstract/Introduction:
This paper examines a patented mobile gas turbine meter proving system that blends technology from liquid turbine meter provers with innovative ideas that particularly apply to gas measurement. Arkla Pipeline Group developed and currently uses this mobile sonic nozzle prover on gas turbine meters ranging in size from 3 thru 16 at meter station sites under actual operating conditions. The prover also incorporates a gas chromatograph which is used in the actual mass flow computations. This system has numerous enhancements over former methods of proving gas turbine meters. Arkla formerly proved its larger turbine meters, having capacities of 60,000 ACFH (Actual Cubic Feet per Hour), with a Roots transfer prover capable of only 10,000 ACFH.
Go to Download Page
Email Reference
Document ID:
E3BF758A
Fundamentals Of Orifice Metering
Author(s): Kenneth E. Embry
Abstract/Introduction:
Throughout the oil and gas industry, there stems the need for accurate, economical measurement of process fluids. Orifice metering satisfies most flow measurement applications and is the most common flow meter in use today. The orifice meter, sometimes called the head loss flow meter, is chosen most frequently because of its long history of use in many applications, versatility, and low cost, as compared to other flow meters available
Go to Download Page
Email Reference
Document ID:
41369E81
Effective Use Of Deadweight Testers
Author(s): Roger Thomas
Abstract/Introduction:
One of the most difficult problems facing the instrument engineer is the accurate calibration of pressure or differential pressure measuring instruments. The deadweight tester or gauge is the economic answer to many of these problems. This paper describes methods to select deadweight testers and gauges. Also included are procedures for using hydraulic deadweight testers.
Go to Download Page
Email Reference
Document ID:
84FDC000
Basic Electronics Foh Field Measurement
Author(s): D. R. Looper
Abstract/Introduction:
This paper hopefully affords readers a broad brushed overview of electronics basics and how they are utilized in todays increasingly technical world. There are references to established formulas and relationships as well as a discussion on acme state-of-the-art technology. The latter is often short changed in these types of presentations and it seemed a good idea to hit some of these basics, too. Perhaps the discussion herein will prove at least informative to those that have limited exposure to computer technology. This understanding is more and more vital to the successful implementation of computerized measurement and automation systems in our Natural Gas Industry.
Go to Download Page
Email Reference
Document ID:
F6A26547
Electronic Transducers And Transmitters
Author(s): Steve Paetz
Abstract/Introduction:
This session covers the electronic transducer and transmitter. Webster defines a transducer as a device that is actuated by power from one system and supplies power (usually in another form) to a second system. Microphones and speakers are one of many types of transducers. In our field of work, we know it to be a device that can transform pressure, tank levels, temperature, etc. into an electrical signal.
Go to Download Page
Email Reference
Document ID:
1E7BDB36
Chart Auditing
Author(s): Michael D. Beck
Abstract/Introduction:
The primary purpose for auditing charts is to verify the integration and volume calculation for a particular site. There are a number of additional benefits to be realized, which we will briefly illustrate. Errors in reported volumes can usually be attributed to one or more of the following reasons: * Mistakes in integration interpretation. * Improperly calibrated machine. * Integrated with incorrect range setting. * Data input errors, * Missed orifice or range changes. * Incorrect meter tube ID used * Improper or missed averaging during times of recorder malftinctions, freezing, etc. * Unaccounted for hours of flow. I * Misinterpretation and/or missed flow around zero line. * Missed gravity or BTU updates. * Unaccounted for recorder errors, found and corrected at inspection. * Incorrect pressure base used. * Temperature averaged incorrectly. * AGA recommended factors not all utilized. * AGA procedures not used.
Go to Download Page
Email Reference
Document ID:
5C310769
From Pen Tip To Volume Statement
Author(s): Philip C. Morris
Abstract/Introduction:
Accurate and reliable gas measurement depends on a combination of efforts and investments. In large companies these efforts include the legal department for contracts, the engineering department for specifying equipment and the purchasing department for buying that equipment. The field service department must then install the equipment. By the time the meter pen tip records the first gas production, there will have been literally dozens of people involved, from land men and geologists to drilling and production people. Regardless of company size there is always a major investment of time and money before the actual measurement process begins. It is the measurement departments job to deliver the results of all of the hard work and money invested.
Go to Download Page
Email Reference
Document ID:
00863448
Field Inspections And Calibrating Measurement Instruments
Author(s): George E. Brown III
Abstract/Introduction:
The following paper details methods and equipment used for checking volume recording and correcting devices that would normally be connected to positive displacement, rotary and turbine meters in lieu of a direct reading/compensating index. The scope of equipment types that are applicable to these procedures are as follows: 1. Volume and Pressure/Temperature Recording Gauges 2. Mechanical Pressure/Temperature Volume Correctors 3. Electronic Pressure/Temperature Volume Correctors 4. Electronic Flow Computers
Go to Download Page
Email Reference
Document ID:
9EA91346
Applications Of Teleietering In Gas Distribution
Author(s): Tom Catey
Abstract/Introduction:
This paper will provide the reader with a general overview of the aethods, applications, and equipment now being utiliied in monitoring and controlling gas distribution and transmission systems. Gas distribution and transmission companies have within their organization departments which are responsible for the monitoring and controlling of pressures, flow rates and volumes. These departments are commonly refered to as gas control and the individual in these departments are referred to as dispatchers.
Go to Download Page
Email Reference
Document ID:
5F6F77C4
Pulsation Effects On Orifice Metering Considering Primary And Secondary Elements
Author(s): Robert J. Mckee
Abstract/Introduction:
The use of raifices for commercial flow measurement has a long history dating back more than SO years. Orifices are extensively used in the United States natural gas, petroleum, and petrochemical industries and are important as one of the most practical ways to meter large volumes of gas flow. These meters are very reliable and cost effective and if properly used, can be reUed upon to give accurate results. Proper use normally requires the steady flows for which orifices were intended and for which the orifice coefficients were developed. In acmal field installations, flow is often not steady but subject to the periodic changes in pressure and velocity that are referred to as pulsations. Pulsations can be caused by compressors, pressure regulators, control valves, fluctuating loads, or by flow-induced phenomena within the piping. It is known and well recognized that pulsations cause errors in orifice meter results.
Go to Download Page
Email Reference
Document ID:
F474209D
Field Testing By Transfer Proving
Author(s): Carlos T. Ponce
Abstract/Introduction:
There currently exists three types of field proving equipment for testing large diaphragm, rotary and turbine meters. The three types are low pressure, critical flow and transfer provers. Both low pressure and transfer proving are generally performed with air and at a vacuum (or in the case of low pressure proving optionally at a slight positive pressure) while critical flow proving is done with gas at 15 #s plus. For transfer proving, the prover is located on the outlet side of the meter being tested, as it is for critical flow proving. However, it may be located upstream or downstream for low pressure proving. Similarly when low pressure proving the blower can be on the inlet or outlet (but always on the opposite end from the prover). The blower location for transfer proving is not only downstream of the meter but also downstream of the prover. In critical flow proving a blower is not necessary.
Go to Download Page
Email Reference
Document ID:
F03BC98F
Fundamentals Of Gas Turbine Meters
Author(s): L. Alan Hess
Abstract/Introduction:
Rockwell introduced the gas turbine meter to the U.S. market in 1963. The original units were 6 flanged meters with a capacity of 30,000 CFH at 4 ounces inlet pressure and 125 pound working pressure cast aluminum bodies. Due to the rapid acceptance of the relatively new gas metering concept by all phases of the gas industry, development of additional sizes and working pressures of gas turbine meters has been fairly rapid.
Go to Download Page
Email Reference
Document ID:
3125F73C
Fundamentals Of Orifice Recorders
Author(s): Paul Toomey
Abstract/Introduction:
This paper will cover the fundamentals of an orifice recorder. The American Gas Association defines the orifice meter as the complete measuring unit consisting of a primary and secondary elements. The meter tube and orifice plate with connection fittings are considered the primary measuring device. The meter or recorder is the secondary device. The meter tube along with the orifice plate is considered the metering device...the recorder or meter, records the events that are created in the meter mbe.
Go to Download Page
Email Reference
Document ID:
ADD0392F
High Pressure Measuring And Regulating Station
Author(s): J. Bryan Butler
Abstract/Introduction:
High pressure measuring and regulating stations are an important part of every pipeline system. Their primary function is to provide safe and dependable high pressure measurement and regulation of natural gas transported from one pipeline to another. High pressure measuring and regulating stations are located along pipeline systems at sales and purchase points such as: O Pipeline interconnects O Industrial sites O Power plants O City gates O Production sites All high pressure measuring and regulating stations consist of numerous components. Today, we will only discuss seven basic components: O Piping O Headers O Control valves O Valves O Overpressure protection O Measurement O Others Since most high pressure measuring and regulating stations transfer ownership of gas, they are the cash registers of gas companies. Their accuracy, safety, and dependabihty are critical. For these reasons design, operation, and maintenance personnel must properly execute their responsibilities.
Go to Download Page
Email Reference
Document ID:
C8CDBDB5
Fundamentals Of Energy Determination
Author(s): Thomas E. Sowell
Abstract/Introduction:
This paper presents fundamental information necessary to understand and appreciate tlie concept of total gas energy in a natural gas pipeline. That is, to be able to converse with peers within the natural gas industry and understand basic concepts and terminology. Discussed Is the historical transition from volumetric measurement to total gas energy including basic terminology, physics, measurement and the reasons for changes in methodologies. Included is the industries acceptance of new concepts and regulations involving custody transfer as well as the instrumentation and systems involved in traditional and newer, more progressive forms of gas measurement.
Go to Download Page
Email Reference
Document ID:
78398866
Field Sampling
Author(s): Doyle N. Hathaway
Abstract/Introduction:
Sampling of natural gas has changed greatly in recent years. This has been necessitated by the change in emphasis fiiom volume to heating value pricing. It has caused the evolution of sampling techniques and equipment necessary to acquire representative samples. This paper will present in some detail the importance of industry standard procedures for procuring these samples.
Go to Download Page
Email Reference
Document ID:
B770E947
Low Power Flow Computers
Author(s): Randall Douglas
Abstract/Introduction:
Flow computers, themselves, are undergoing an evolution. One challenge for most vendors will be to offer a low power flow computer whose pricing approaches that of a three variable chart recorder. Many companies in the gas transmission, gas distribution and production industry , expect such a flow computer to be an evolution from todays smart transmitter technology, because of improved accuracy and innovation of multi-variable transmitters. That is to say, differential pressure, static pressure and temperature all in one transmitter.
Go to Download Page
Email Reference
Document ID:
5CDC034C
Natural Gas Sweetening With Alkanolameves
Author(s): Rick Baldwin
Abstract/Introduction:
Natural gas as produced from the wellhead contains several undesirable components. Hydrogen Sulfide (H2S) and carbon dioxide (CO2) are two of the more commonly encountered impurities found in a typical wellhead natural gas stream. Hydrogen sulfide and carbon dioxide are called acid gases because they form weak acids when combined with water. Hydrogen sulfide is a toxic gas which must be removed from natural gas before it can be used as a commercial fuel. The following table lists the toxic effects of hydrogen sulfide:
Go to Download Page
Email Reference
Document ID:
2425D888
Periodic Inspection Op District Regulators & Relief Valves
Author(s): George L. Bell
Abstract/Introduction:
Inspections of district regulating stations and overpressure protection devices are essential in complying with Federal and State Regulations. District regulators reduce high inlet pressure to a lower outlet pressure that is below the maximum allowable operating pressure (M.A.O.P.) for a segment of pipeline. The district regulators may also be used to reduce an intermediate pressure to an even lower utilization pressure. District regulators may be installed for your companys operation to reduce a line segments lost and unaccountable, gas purchased, tapping requirements, or odorization problems, Overpressure protection devices are devices that protect the downstream pipeline in the event of a regulator failure. These devices include the relief valve, the monitor, and the pressure shutoff.
Go to Download Page
Email Reference
Document ID:
13DF8054
Minimizing Gage Line Distortion Through Manifolds
Author(s): Dave Bell
Abstract/Introduction:
The natural gas industry has been using orifice meters for custody transfer since the early 1900s. Not until the late 1980s has the orifice regained its reliability. It really never lost its dominance only some people thought that other types of meters would do the job easier and with greater accuracy. Through the introduction of the electronic transmitter and the electronic flow computer the problems with pulsations were exposed to all modes of measurement. Through establishment of the Pipeline Compressor Research Council by the Southern Gas Association and in conjunction with the Southwest Research Institute, San Antonio, Texas, years of data gathering in the lab and in the field found the orifice was not the root to all evil in custody transfer. All this data is now public domain for public use. This paper will show how the manifolds of present design has helped to minimize problems in measurement accuracy and in some installations completely solved gage line distortions.
Go to Download Page
Email Reference
Document ID:
2AE819E9
Fundamentals Of Pressure Regulation
Author(s): Robert Bennett
Abstract/Introduction:
A regulator may be defined as a mechanism for controlling or governing the movement of machines or the flow of liquids and gases, in order to meet a standard. The primary function of a gas or liquid regulator is to match the supply of the fluid moving through It to the demand for the fluid downstream. To accomplish this, it measures the downstream pressure and makes adjustments accordingly.
Go to Download Page
Email Reference
Document ID:
94E73C35
Fundamentals Of Self Averaging Pitot Tubes
Author(s): Darrell Pebley
Abstract/Introduction:
Just because a flow measurement device is complex and/or expensive does not automatically mean that it is the best or most accurate. Oftentimes the most simple device is just as good and accurate and frequently even better. Economic pressure encourages the emergence of better all-around devices with greater reliability and accuracy. These and other factors have brought to the fluid flow measurement industry the Multiport Averaging Primary Flow Measurement Device. This refined version of the basic pitot tube, the same as the orifice and other headtype primaries, is based on the same standard hydraulic equation, continuity equation and Bernoullis Theorem. Thus, an extension and improvement of proven concepts and device makes available to the industry a primary flow measurement device which offers many benefits, including a simple design, with equal or better performance for fluid flow measurement and process control applications.
Go to Download Page
Email Reference
Document ID:
2737C73F
Fundamental Gas Laws
Author(s): Rogers G. Thompson
Abstract/Introduction:
We as gas measurement people are concerned with gas laws. To become proficient in all phases of gas measurement, one must fully understand what natural gas is and the theory of its properties. The theories about natural gas properties are the gas laws, and their application is essential to gas measurement. Quantities of natural gas for custody transfer are stated in terms of standard cubic feet. To arrive at standard cubic feet from actual flowing conditions requires application of correction factors that are defined by the gas laws.
Go to Download Page
Email Reference
Document ID:
93C790AC
Problems Unique To Offshore Measurement
Author(s): James G. Young
Abstract/Introduction:
Most of us have arrived at this meeting in some kind of company provided transportation. This is supplied in order for us to do our assigned jobs. These may be trucks, cars, helicopters or even boats. For those who are involved in the offshore industry we know that transportation involves the greatest expense. The helicopter expense for our company is close to the 9 million dollar range, Since this cost is so high, we are constantly looking at ways to reduce it. The helicopters we use cost us 510.00 per flying hour plus 28,000.00 a month for leasing.
Go to Download Page
Email Reference
Document ID:
51EA043E