Design Of High Pressure Metering And Regulation Stations
Author(s): Jimmie L. Butler
Abstract/Introduction:
What is high pressure? Any pressure greater than utilization or, as most companies define utilization pressure, 6 inches water column? Does your company consider 10 psig to be high pressure? 100 psig? 1000 psig? As the old saying goes, everything is relative. Therefore, each company must decide internally what it considers to be high pressure. Later discussion will touch on topics generally associated by industry with high pressure meter and regulator stations.
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Document ID:
2A9A7651
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
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Document ID:
0DAC958D
Effects On Entraihed Liquid On Orifice Measurement
Author(s): C. V. Mooney
Abstract/Introduction:
In the measureinent of natural gas in field operations using the conventional orifice meter, all of the factors used in the calculation of flow are hased 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, (1), does not give any informatioi 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 condpcted research operation in the laboratory and ih the field.
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Document ID:
47F13748
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 from 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 inqurtance of industry standard procedures for procuring these samples.
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Document ID:
8278A378
Training In The Volume Processing Office
Author(s): Judy T. Pawlik
Abstract/Introduction:
When someone begins a new and exciting career in measurement, they are truly about to embark on an incredible journey!! They couldnt possibly have any idea whats in store for them!! You could throw them out there to sink or swim - but then again it could be your company doing the sinking carrying you and your fellow employees with it. If the company is to be successful, then it must have a successful Measurement Department. For this reason, trainers are needed to train the new hires, or perhaps to train an experienced employee in a new task.
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Document ID:
E0ADA1C5
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.
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Document ID:
90D52D8E
Design Considerations For Orifice Meter Tubes
Author(s): Ray Kendrick
Abstract/Introduction:
The 1991 release of API Chapter 14, Section 3, Part 2 is essentially an update of the 1985 ANSI/API 2530 (AGA-3) document. This standard is the result of an intensive test program involving 11 laboratories, utilizing 3 test fluids and collecting in excess of 10,000 data points. The results suggest certain changes from the previous document and allowed the authoring of a new equation. This paper will cover basic overall orifice meter tube design guidelines as well as indicating some of the changes noted in the latest API 14.3 document.
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Document ID:
8741CAAD
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.
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Document ID:
8B66D337
Basic Electronics For Field Measurement
Author(s): O. 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 some 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 Co computer technology. This understanding is more and more vital to the successful implementation of computerized measurement and automation systems in our Natural Gas Industry.
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Document ID:
71009535
Computer Applications In Chart Processing
Author(s): Russel W. Treat
Abstract/Introduction:
The natural gas business has been undergoing an incredible amount of change in recent years, and the gas measurement department has not been exempt Significant changes in regulation and maricet 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.
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Document ID:
E1B0932E
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.
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Document ID:
88F1AE6B
Effect Of The Latest Revision Of Ansi 2530 (AGA #3) On The Primary Orifice Metering Element
Author(s): Douglas Watkins
Abstract/Introduction:
Significant improvements in the equations which govern tiie measurement of natural gas using orifice meters, have necessitated changes in the primary devices used to gather the data. These changes have been incorporated into the new revision of the API 14.3 Part 2 Third Edition (AGA-3, ANSI 2530) and are detailed in the following discussion.
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Document ID:
C2B73E32
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 content rather than by volume alone. to its energy 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.
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Document ID:
7E8982C0
H2S Detection And Determination
Author(s): D. Marshall Brown
Abstract/Introduction:
Hydrogen sulfide is measured in the natural gas industry for three main reasons: 1) personal safety, 2) corrosion control, and 3) contractual obligations. Because hydrogen sulfide is very toxic, leaks must be detected rapidly to prevent injury and loss of life. Toxicity information based on the concentration of hydrogen sulfide and the time of exposure can be found in table 1. At low ppm/vol concentrations hydrogen sulfide has a rotten egg odor. As the concentration increases, ones sense of smell is no longer useful for detecting the presence of hydrogen sulfide. Concentrations above 700 ppm/vol are almost instantaneously lethal.
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Document ID:
14317ADE
Electronic Flow Meter Auditing
Author(s): Gary P. Menzel
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.
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Document ID:
6ED5BF2B
Pulsation Effect Of Gas Turbine Meter Measurement
Author(s): Zaki D. Husain
Abstract/Introduction:
Turbine meters are commonly used for large volume gas measurement application, therefore, accuracy, rangeability, and reliability are essential. Properly maintained and calibrated, gas turbine meters at steady uniform flow can provide reliable and accurate flow measurement. Because of the current and growing use of turbine meters it is essential to maintained and certify high accuracy turbine flow measurement under field conditions.
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Document ID:
D2144C62
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 oper ator s imu late the act ions in the recording meter. The Chart Procesor computes and prints (for each chart) the chart extension (JH.P), average pressure and flow time. It also stores and prints batch totals on command.
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Document ID:
AD111887
Fundamentals Of Gas Turbine Meters
Author(s): Angela Floyd
Abstract/Introduction:
A wide variety of gas measurement equipment exist in the US market place. The bulk of the gas measurement devices in North America consist of the diaphragm, rotary, turbine and orifice meter. Each meter has its advantages, limitations and trade - offs, and is application dependent.
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Document ID:
E0020805
Fundamentals Of Orifice Meter Recorders
Author(s): Jerry Koch
Abstract/Introduction:
This paper will cover the fundamentals of an orifice recorder. For many years the orifice recorder has been the most widely used measurement device in the natural gas mdustry. It is used to account for the gas volumes moved through the orifice meter for custody transfer and allocation purposes, as an event logger, arid as an aid in trouble shooting system problems. The accuracy and repeatability of the orifice recorder are extremely important because inaccuracies can result in substantial losses or gains in income to the parties involved.
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Document ID:
0288C8B7
Low Power Flow Computers
Author(s): Larry A. Quick
Abstract/Introduction:
Flow computers are specially designed micro-processor controlled CPUs specifically constructed to collect, calculate, store, and transmit flow measurement data to a host system along with audit trail and alarm information. They are an essential part of electronic fluid flow measurement, and are usually installed in various remote locations throughout the oU and gas production, transmission and distribution industries. The primary use of a flow computer is to measure the transfer of a fluid from one point to another, however, most flow computers are now able to execute Umited flow control commands also. All the flow computer functions are controlled by on-board firmware, sometimes in conjunction with inputs from the host system. It is this on-board firmware, and associated host software, that allows the user to maximize the flow computers versatility and efficiency. Since flow computers measure (and as just stated, sometimes control) the transfer of ownership of a flowing fluid, they are essentially the cash registers of the oil and gas companies.
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Document ID:
3DD1D985
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.
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Document ID:
ECA39ABE
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.
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Document ID:
0D95C118
Influence Of The Latest Revision Of Ansi 2530 (A6A #3) On Flow Computer 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: Part 1-General Equations and Uncertainty Guidelines Part 2-Specifications and Installation Requirements Part 3-Natural Gas Fluid Measurement Part 4-Implementation
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Document ID:
06B6DC3E
Fundamentals Of Energy Determination. Basic Methods Of Heating Determination
Author(s): Thomas E. Sowell
Abstract/Introduction:
This paper presents fundamental information necessary to understand and appreciate the concept of total gas energy in a naturai 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.
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Document ID:
7059FAD2
Communication Between Ofhce And Held
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 ofHce, 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.
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Document ID:
1803E0F3
Fundamentals Of Rotary Metering
Author(s): Todd A. Reeves
Abstract/Introduction:
The first positive displacement rotary gas meters were built in 1920 by the PH & FM pOOTS Company and the Connersville Blower Company, both located in Connersville, Indiana. In 1966, this gas meter operation was renamed Dressed Measurement Division, However, these rotary meters today are still known as ROOTS Meters. Rockwell International entered the market in the early 1960s with a rotating vane design known as the ROTO-Seal Meter, and in the late 1960s Singers American Meter Company introduced still another rotating design known as the CVM gas meter. There are several foreign competitors who also manufacture a lobed rotary meter.
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Document ID:
B6B74C81
Applications Of Telemetering In Gas Distribution
Author(s): Tom Cathey
Abstract/Introduction:
This paper will provide tha reader with a general over view of the methods, applications, and equipment now beinq utilized in monitoring and controlling gas distribution and transmission systems.
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Document ID:
CCB17498
Techniques Of Natural Gas Sampling
Author(s): Kris Kimmel
Abstract/Introduction:
In recent years, the measurement of natural gas has experienced tremendous change. The acceptance of electronic flow measurement, as a common practice, has no doubt changed the method and time required to measure gas in custody transfer and allocation applications. With changes in industry standards, and technology, we will see more advancement in this area in the future. Another closely related area of measurement, which has experienced change in recent years, involves the sampling for quality of natural gas. These changes include developments in instrumentation, and a new sensitivity to the importance of proper sampling techniques to insure the integrity of the sample before analysis. The concern in the accuracy of the sample, naturally, may involve the monetary considerations of custody transfer, the balancing of a gas gathering system, or even the control of a process within a plant. But always, it is the composition of the sampled gas, acquired in such a manner, deemed representative, and then related to flow that is important.
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Document ID:
C70660F6
Lightning Protection And Grounding For Remote Flow Computers
Author(s): Clifford R. Pelchat
Abstract/Introduction:
The purpose of this paper is to discuss the methods that can be used to protect electronic equipment from electrical surges caused by lightning. Probably everyone reading this article can share an experience where damage to sonic electronic device was caused by lightning. Lightning can strike utility structures a great distance from a meter installation and still cause major damage to the electronic instrumentation. These strikes can cause surges on telephone lines, AC electrical lines. and sometimes, buried steel pipe lines. At times these surges can reach several thousand volts. Protection is generally achieved by diversion and shielding or by limiting the amounts of currents and voltages that can pass through the equipment 1 will discuss a typical installation and the steps that you can take to provide proper grounding, (diversion), and some of the methods and devices that are used to limit current and voltage.
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Document ID:
D42883CC
Traceability Of Test Instruments Selection, Applications, And Use
Author(s): Gregg m. Kloeppel
Abstract/Introduction:
How good is the measurement you are making and is the measurement as good as the measurement you made yesterday, a week ago, or even a year ago. We will review the selection of test instruments and why an instruments accuracy, repeatability, operating temperature and traceability is important to the ultimate goal of a good measurement. Next we will look at the measurement process and what relevant factors influence the collection of data for measurement assurance. Finally, we will review both National and International Standards for maintaining instrument traceability and the requirements for maintaining documented traceability.
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Document ID:
2654C188
Fudamentals Of Natural Gas Safety
Author(s): Linton T. Lipscomb
Abstract/Introduction:
Natural Gas: A combustible mixture of methane and higher hydrocarbons used chiefly as fuel and raw material. To safely produce natural gas and natural gas products, a basic understanding of the hazards of the material itself and the processes required to bring it to market is essential. Lets start out with the hazards of natural gas as it is in its raw field gas state: 1. Flammable/Explosive 2. Hazardous Impurities a. Hydrogen Sulfide b. Benzene c. CO2 d. Liquid, Petroleum Gases (LPGs)
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Document ID:
C9547188
Gri Metering Research Facility Update
Author(s): William J. Astleford, John G. Gregor
Abstract/Introduction:
Deregulation of the natural gas industry, FERC Order 636, and the business economic climate has resulted in significant changes to industry operations. Increased emphasis is given to the timely and exact tracking of natural gas as it moves from the production wellhead through the gathering, transmission, and distribution system. Improved flow measurement technology is necessary for accurately and cost-effectively canying out this monitoring process.
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Document ID:
466E15A7
Networked Gas Measurement Systems
Author(s): Steve Ogorman
Abstract/Introduction:
There are many design considerations associated with the development of systems that can measure gas flow and transfer the data to a central location. A systems perspective is required when considering the use of electronic gas measurement to satisfy the business and operational challenges that are present in todays gas industry. It is essential to understand the functions of individual components and how they will become integrated into a complete, networked system. Financial tools are often used to evaluate different component selections. As well, a proposed analysis can be utilized by designers to approximate the uncertainty associated with any measurement system.
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Document ID:
DFEAEA2D
Natural Gas Contract
Author(s): Robert L. Wimpee, Jr.
Abstract/Introduction:
The purpose of this discussion today is to present the natural gas contract from the measurement viewpoint. It will be to your advantage as a measurement person to understand the extreme importance of measurement in a gas purchase contract and the administration of issues involved which center around measurement.
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Document ID:
C68D3637
Odorization Of Natural Gas
Author(s): Scott P. Youngblood
Abstract/Introduction:
The odorization of natural gas evolved from a fragmented, unregulated practice at the turn of the century to the current highly regulated and monitored practice we see today. The evolution to todays standards and governmental regulations stems from an increased awareness of risks and public safety and the increased use of natural gas. As always, the primary focus of odorization is safety, we must keep this in mind as we develop, maintain, and improve our odorization technics and processes in a changing regulatory environment. This paper covers a brief history of natural gas odorization, the chemicals used in odorants, odorization technics, odorant handling, and developing programs to address responsible care and emergency response needs.
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Document ID:
0FB1450E
Direct Measurement Of Energy, Description Of Equipment, Methods, And Calculations
Author(s): Thomas E. Sowell
Abstract/Introduction:
Why measure total gas energy as opposed to volume at base conditions? It is a matter of economic fairness. With open access to pipelines and the right to negotiate gas contracts on an interstate or even international basis. Heating values, (the overall quality of natural gas), has become an additional variable to factor In the usage of gas as a commodity. In the past gas quality was relatively constant due to the chain of custody linking a particular field or fields to particular customers. Open access has radically changed that concept. The Federal Energy Regulatory Commission (FERC) now mandates custody transfer to be accomplished on an energy basis. This effectively adds calorific value as another variable in the calculation of billings for custody transfer.
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Document ID:
6E97D214
Chart Auditing
Author(s): Angelia Parish
Abstract/Introduction:
Chart auditing is of equal value to original measurement work. The monetary value of potential volume and BTU adjustments justify the existence of an audit group or the addition of audit fionction. A measurement department that delivers only original measurement misses the opportunity to increase the contribution it makes to the company served using existing skills and equipment. However, measurement skills represent only one of the ingredients necessary for a successflil chart audit function. The components other than measurement skills constitute the subject I will pursue. Because the department for which I work is an example of the application of many of these components, it will serve as the model for this presentation. Elements covered are:
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Document ID:
9485D0C5
Egm Data Editor Requirements
Author(s): Michael Squyres
Abstract/Introduction:
The natural gas industrys adoption of EGM as a means of increasing the speed and accuracy with which measurement information is obtained, has created the need for an electronic data management system. These systems, if not properly designed and implemented, could potentially render the entire process useless. Therefore, it is essential that the system add functionality that complements the power of the hardware. With proper implementation, such a system will not only facilitate operations in todays fast paced, post-FERC 636 envirorunent, but also will establish a foundation for meeting tomorrows measurement challenges.
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Document ID:
E432ADC2
C6 - Electronic Vs. Mechanical Correcting Devices Two( Approaches For Volume Corrections On P.D. And Turbine Meters)
Author(s): Warren m. La Mar
Abstract/Introduction:
Today we are here to discuss the electronic volume corrector versus the mechanical volume corrector. First a small bit of history, as you can see from this chart, (Figure 1) in the mid 1920s the meter mounted chart recorder came into existence. Around 1930, the mechanical volume corrector or volume correcting index came into being. These mechanical correctors used several methods of applying pressure and temperature correcting factors, based on Boyles Law for pressure and Charles Law for temperature, to the uncorrected metered volume. Also, in some instruments the ability to apply the supercompressibility factor in a limited fashion using some fixed values for specific gravity, nitrogen percentage, and carbon dioxide percentage.
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Document ID:
B8FB649D
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.
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Document ID:
69E3F1EA
Electronic Transmitters
Author(s): Jim Griffeth
Abstract/Introduction:
What is a TRANSDUCER? What is a TRANSMITTER? What is the difference between a transducer and a transmitter? What is the difference between Gauge, absolute, and differential pressure transducers? Why is one transducer more accurate than another? How does a, transducer & transmitter work? How often should one transducer or transmitter calibrate? Over the course of this paper we will answer the above questions in enough detail as to satisfy most field technicians.
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Document ID:
74A9795A
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.
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Document ID:
F2A9252F
Instruments For The Determination Of Specific GRAVITY/RELATIVE Density Of Gas
Author(s): Richard Balcerak
Abstract/Introduction:
The terms Specific Gravity and Relative Density have been used for a number of years. Yet there seems to be some confusion over what exactly they mean. Specific Gravity is formally defined as the ratio of gas density to air density when both are at standard conditions of 0 Degree C and 760 mm. Over the years the definition evolved tO become the ratio of gas density to air density at the same temperature and pressure, Relative to each other. Hence, the term Relative Density. This is the most commonly used definition today. The American Gas Association in 1985 officially replaced the term Specific Gravity with Relative Density. However, both terms are still used synonymously.
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Document ID:
CC0A3706
Choosing The Compleat Gas Measurement System
Author(s): Richard L. Cline
Abstract/Introduction:
Since the discovery of oil and gas and the advent of coranercial conveniences v*iich use oil and gas, ccmpanies have been confronted with the need to aocuicitely mscisure the oil and gas bought and sold in the marketplace. And, as usual, the technology available at the time was brought to bear on the measurenvent process. All gas ocmpanies must, of course, deal with gas measurement and are positioned scmevAiere on the autcffnation curve. As time moves forward, so does the technology. New products and measurement techniques are constantly being offered to irrprove the gas measurement process. Lfrifortunately, adopting the new technology always hrin with it a price. And the price is not only cost, but an ever increasing difficulty in making intelligent decisions and choices.
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Document ID:
3A5898A1
A New Perspective On Measurement
Author(s): Lohit Datta-Barua
Abstract/Introduction:
We have all heard various slogans and words about measurement such as Measurement is the cash register, Measurement is a necessary evil, Measurement is an inexact science, etc., and there may be some truth in them. Unfortunately, the measurement persons perspective of measurement has not changed much with time. We recognize that new technology and a new business environment have complicated our lives, but the overall view has been very narrowly and technically focused. We talk about the technical defensibility of what we do without taking responsibility for its economic impact. We revise technical documents, and we get carried away with the best accuracy at any cost. We apply the latest and greatest supercompressibilily calculations to six decimal places to calculate a few MCF of gas which flow through an oversized meter run that has not been checked in a long time. The bottom line is: We cant see the forest for the trees.
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Document ID:
98C92AB7
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.
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Document ID:
A393BB42
Operation Of On-Line Chromatography
Author(s): Paul E. Kizer
Abstract/Introduction:
On line gas chromatography is today being chosen more and more in the natural gas industry for monitoring of gas quality. The calculations of the gas volumes in modern electronic flow meters requires not only BTU5(A BTU, British Thermal Unit, is a measure of heat) information, but specific gravity, Mol. % CO2 and Mol. % N2 as well. In addition, the current AGA-8 supercompressibility equations also require a complete analysis for the detailed method of calculation of Fpy. Most natural gas custody transfer contracts today use MMBTU rather than MCF as the accounting units of gas transfer. Also, modern micro-packed columns are providing faster cycle times for time critical BTU measurement applications. For these realms mentioned above, and the fact that the installation requirements for chromatographs are less stringent than calorimetric methods, the use of gas chromatographs has become standard practice.
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Document ID:
2EAC1614
Performance Characteristics Of Transit Time Ultrasonic Flow Meters
Author(s): W. R. Freund, Jr., K. L. Warner
Abstract/Introduction:
Transit time ultrasonic flowmeters are increasingly being used in the measurement of natural gas flows. Multipath ultrasonic flowmeters are sufficiently accurate for custody transfer metering. The operating characteristics of these meters are explored by means of a model whose performance is linear with average velocity. Calibration of multipath ultrasonic flowmeters using chordal integration techniques can be accomplished with measurements of the geometry of the meter and delay times for the transducers. The effect of measurement errors in geometry and time on the performance curve of the meter are studied. Test results are given for 300 mm and 150 mm ultrasonic flowmeters.
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Document ID:
EA321991
Fundamentals Of Positive Displacement Diaphragm Metering
Author(s): Robert Bennett
Abstract/Introduction:
The first gas company in the U.S., The Gas Light Company of Baltimore, Maryland, founded in 1816, struggled for years with financial and technical problems while operating on a flat rate basis. Its growth was slow with the charge for gas service beyond the pocketbook of the majority. By comparison, the New York Gas Light Company, founded m 1823, prospered and expanded. They had built their system on the use of gas meters to measure the supply of gas to customers, and a large one to register the quantity made at the station before it is conveyed to the gasometers
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Document ID:
A258A4FE
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.
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Document ID:
3EA18DC5
Fundamentals Of Gas Laws
Author(s): John L. Chisholm
Abstract/Introduction:
In the gas industry a standard unit of measure is required. In the English system it is the standard cubic foot. In the metric, it is the standard cubic meter. This standard unit is the basis of all exchange in the gas industry. When the unit of purchase is the energy content (BTU) we achieve it by multiplying the BTU content of a standard cubic foot times the number of cubic feet delivered to the customer. So we must obtain standard cubic feet or meters. A standard cubic foot is defined as one cubic foot of gas at a pressure and temperature agreed upon by the buyer and seller. Common standard conditions are 14.73 psia and 60 Fahrenheit. The gas passing through a meter is rarely at standard conditions. It is necessary to convert the gas in the meter from the metered conditions to standard cubic feet. The tools we have for relating volume to pressure and temperature are Equations of State or, simply, the Gas Laws.
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Document ID:
DEE30665
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.
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Document ID:
17756334
Fundamentals Of Orifice Metering
Author(s): Greg m. Phillips
Abstract/Introduction:
The purpose of this paper is to discuss the fundamental components used in orifice measurement. The general concepts of head meters, which include the orifice, have been known for centuries. The orifice has been in commercial- use since the early 1900s. The device is used to create a differential pressure which relates to the velocity of the gas from which a flow rate can be calculated. As the flowing gas passes through the restriction in the line caused by the orifice plate, the difference in the ufpstream and downstream pressures can be measured at set points, call taps, and a flow rate at the point can be determiined.
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Document ID:
C9B28214
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 mdidnt 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.
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Document ID:
60C2C658
Training Gas Measurement Personnel
Author(s): A. S. Harris, Jr.
Abstract/Introduction:
Todays technology in the field of gas measurement is constantly changing, and the training of its measurement technicians is of the utmost importance. These technicians must be continually educated in order to possess the most current knowledge of the latest equipment on the market today. Also, it is essential that this type of instruction should be taught in a controlled environment where the technicians can learn and develop the necessary skills with the least amount of interruptions from external sources.
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Document ID:
113854A0
Unaccounted-For Gas
Author(s): Mike Haydell
Abstract/Introduction:
Unaccounted-for gas figures can be either positive (more gas purchased than sold) or negative (more gas sold than purchased). In either case, it is important to determine what factors are contributing to the imaccounted-for gas and eliminate them. We are concerned about unaccounted for gas for two reasons safety and economics. Concern about unaccounted-for gas for public safety include: leakage, third party damage and gas theft. These factors contribute to unaccounted-for gas that can adversely affect the safety of our customers. Economically, unaccoimted-for gas represents lost revenues that are not recoverable. It is gas purchased ft-om a supplier but not sold to customers (positive unaccounted-for gas).
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Document ID:
960FDEAF
Fundamentals Of Egm - Electrical Installations
Author(s): Michael D. Price
Abstract/Introduction:
The areas of gas measurement and communications have seen substantial changes in the last few years as the natural gas industry adapts to effects of the economy, low gas prices, warm winters and government deregulation. Every company has studied, debated, hired consultants, and finally determined how gas flow data is to be measured and collected. All gas companies have hundreds and even thousands of points which must be accurately measured. Data is retrieved from very remote and rugged locations. Climate conditions can range from humid off-shore platforms to desert conditions with both temperature extremes included. No commercial power is available, allowed or even desired at these locations making the solar-powered electronic gas measurement equipment the ideal method of gathering flow data.
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Document ID:
6745D685
Determination Of Water Vapor Content In Natural Gas
Author(s): Borys J. Mychajliw
Abstract/Introduction:
With todays focus on quality, an accurate and reliable means of determining the water vapor content of natural gas is of great importance. This paper will discuss several different sensing technologies available to perform this task.
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Document ID:
6E8C91D6
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 filters. 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.
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Document ID:
051A9038
Portable Gas Chromatograph
Abstract/Introduction:
The production and custody transfer of natural gas requires accurate measurement of the composition of the gas. Contractual requirements usually define the desired composition, heating value, relative density, and moisture content of the gas being sold. The sale of natural gas is performed on the basis of the heating value per iinit volume (kJAn or Btu/Scf) of the gas. For these reasons, the industry has used instruments to monitor the characteristics of the gas at the point of sale. The following instruments are commonly found in the field and in the laboratory: Gas Chromatographs Gravitometers Moisture Analyzers Densitometers Hydrogen Sulfide Monitors Oxygen Monitors
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Document ID:
50350BB3
Fundamentals Of Pressure Regulation
Author(s): James Kobetis
Abstract/Introduction:
A self-operated regulator is a very simple device that confiises many newcomers to the industry due to its strange terminology. This paper will discuss the basic purpose of regulators, the basic design of regulators, what affects their performance, things to consider when sizing a regulator and, capacity calculations for safety devices. Such mystifying terms as loading element, sensing element, restricting element, droop, boost, spring effect, diaphragm effect, body effect, inlet pressure effect, lock-up, monitor regulator, fiill open capaci and, rated capacity will be explained.
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Document ID:
654F3007
Methods Of Gathering Egm Data
Author(s): Roland Rollins
Abstract/Introduction:
The choices of communication options presently available are: radio/microwave (RS-232), telephone (land line and cellular), wire ax short haul (RS-485), VSAT (very small aperture), LSAT, or a combination of these. LSAT is a DC powered satellite system in which the dish need not be aligned with the satellite. It was first used in the trucking industry. The following table highlights the main capabilities and limitations of each type of commtmication option available. A canbination of methods often is needed, so dont overlodc a mixed system.
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Document ID:
271AF34A
Field Testing Of High Pressure Gas Turbine Meters
Author(s): Maurice Barnes, Jr.
Abstract/Introduction:
The accuracy of a field meter station in natural gas operations should be verified directly under actual operating conditions by a master meter or prover. In recent years, new provers have been developed for operation at high line pressure and flow rates. This paper evaluates turbine meter dynamics, effects of gas composition on prover accuracy, and two prover technologies available for field proving of high pressure gas turbine meters.
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Document ID:
97629FD6
Report On API Egm Standard
Author(s): Brent E. Berry
Abstract/Introduction:
In September of 1993 API published a new section of the Manual of Petroleum Measurement Standards titled Chapter 21 Flow Measurement Using Electronic Metering Systems. Section 1 Electronic Gas Measurement. This report provides an overview of the API 21.1 document with the intent of serving as a primer and something of an introduction to the publication. The 21.1 standard was developed by representatives from the American Petroleum Institute (API), American Gas Association (AGA) and Gas Processors Association (GPA) member companies with input from equipment manufacturers and others. The 21.1 standard represents the first API pubUcation in the field of electronic metering systems.
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Document ID:
B26379B3
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 that 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: (1) 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).
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Document ID:
78BEB3C4
Orifice Meter Test Procedures For Chart Recorders
Author(s): Curtis R. Fillman
Abstract/Introduction:
Orifice meter measurement with a chart recorder has been a standard in the petroleum industry for years. The orifice meter consists of the plate and tube (primary element), and the recorder (secondary element). It has been popular for years because the meter is a simple device which requires minimal maintenance and can accurately measure a wide range of flow rates. Orifice meter measurements can affect sales, reservoir engineering, production allocation, gas allowables, royalties, and, uitimatel y, your paycheck. Therefore, it is important that the meter be routinely tested to ensure sustained accuracy. The frequency of the meter lest is dictated by company policy, contract, or when the meter is thought to be in error. Most companies test their meters monthly or quarterly, depending upon the volume of gas measured.
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Document ID:
B392E7E3
Pulsation Effects On Orifice Metering Considering Primary And Secondary Elements
Author(s): Robert J. Mckee
Abstract/Introduction:
The use of orifices for commercial flow measurement has a long history dating back more than 50 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 relied 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 actual 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. In fact, A.G.A. Report No. 3 on Orifice Metering of Natural Gas, which is also ANSI/API 2530, clearly states that: Reliable measurements of a gas flow with an orifice cannot be obtained when appreciable pulsations . . . are present at the measurement point.
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Document ID:
8C718800
Transfer Provers
Author(s): John D. Gray
Abstract/Introduction:
A Transfer Prover consists of a master meter mechanically set to zero percent error. It is equipped to read temperature, pressure and correcting for any difference between the master and fleld meter- Transfer Prover 12185 was my first prover. It came to me in 1975. Technology has moved rapidly in the gas industry with provers now being rim by laptop computers. This enables field technicians to pre-conflgure and save to the menu any meters and their desired flow rates. The latest provers warn of high differential, low test times, questions as to your purging meter of gas after blocking meter in, and taking pressure off the meter. If your transducers sense any pressure, it is programmed not to allow the test run to start. This safety feature should make you attend to any gas leaking by the valves that have the meter isolated from flow of gas to customers.
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Document ID:
AC25D9F3