Measurement Library

American School of Gas Measurement Technology Publications (1989)

American School of Gas Measurement Technologies

Certification Of Calibration Standards
Author(s): Doug Laplant
Abstract/Introduction:
Todays highly advanced and sophisticated instrumentation requires very carefully prepared calibration standards for maximum accuracy. The potential dollars lost due to a poor standard can be tremendous. The emphasis today is on consistent and quality manufacture of specialty gas mixtures backed up by a strong quality control program. Although there are several specialty gas manufacturers, quality and technical support offered will vary. Accuracy and reliability of instrumentation has improved tremendously since its beginnings. With these improvements there is still a dependency on the reference point - the calibration standard.
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Document ID: 6CEA8969

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 services 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. An investment of thousands of dollars will also have occurred. 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: 4FDAF898

Orifice Meter Testing
Author(s): Gail Ledbetter
Abstract/Introduction:
In orifice meter testing there are three primary elements which must be observed to assure the accuracy of the orifice meter. They are the meter tube, the orifice plate and the orifice meter. Each element has criteria which mast be met to conform to the AGA Report #3. In the following paragraphs we will look at each element as it pertains to testing an orifice meter.
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Document ID: 7ED5DD9E

Fuhdamental Principles Of Rotary Displacement Meters
Author(s): Rick Gregorczyk
Abstract/Introduction:
In North America almost all natural gas is measured by four types of meters: Diaphragm, Rotary, Turbine and Orifice. Diaphragm and Rotary meters are classified as positive displacement meters. They measure gas by alternately filling and emptying measurement chambers of a fixed and known vo1ume. Rotary meters have been in use for over 60 years in the gas industry. The first meters were foot mounted and constructed of cast iron. In the past 20 years the majority of Rotary meters put in service have been constructed of aluminum and are line mounted. The Rotary meters long-terra track record ou reliability, accuracy and versatility has made it useful in nearly all aspects of gas measurement. Applications for rotary meters include: at the wel I he ad in gas production and processing, in compressor stations for transmission, and for commercial and industrial distribution measurement.
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Document ID: A6345CE1

Fundamental Principles Of Regulators
Author(s): L. Alan Hess
Abstract/Introduction:
A Gas Pressure Regulator is an Automatic device which controls the media flow and maintains a desired media pressure while reducing the media supply pressure, The basic regulator could be an operator at a control valve watching a pressure gauge. The valve is manually opened to allow the line pressure to achieve the desired gauge setting. The operator then visually monitors the gauge and either opens the valve or closes it to maintain the desired pressure. The problem with this system is it would require fulltime operators for daily operation and continuous monitoring of the gauge. The regulator products on the market do not monitor the gauge, however, via monitoring the outlet pressure, they do automatically open and/or close the valve to control the outlet pressure at an established valve.
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Document ID: A0CADD3E

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.
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Document ID: A48EDC97

Design Of High Pressure Measuring Regulating Stations
Author(s): John m. Stephens
Abstract/Introduction:
The primary function of a measuring regulating station is accurate measurement of flow, particularly where the measurement is used as the basis of sales (custody transfer) of gas from one party to another. Parallel to this is dependable regulation of high pressure gas from gathering systems or transmissions systems to lower pressure receiving systems. The areas of concern in designing a station include:
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Document ID: 3C81AEAB

Turbulence And Its Effect In Measuring And Regulating Stations
Author(s): Mike Mckay
Abstract/Introduction:
For several years gas men have been giving more thought to aerodynamic turbulence within their pipeline systems and, in particular, the turbulence that is a result of pressure regulation. Considering the noise from a measurement or regulating station, it is generally conceded that measurement facilities alone will rarely be a major source of noise, since we can design the pipe to give a desired and normally tranquil velocity. On the other hand, we must expect that in a regulator station control of the gas velocity is possible only up to the Inlet side of an active regulator. At the point of regulation within the regulator body, the velocity of the gas may be expected to increase greatly, perhaps up to sonic velocity. Now the question becomes, What is the best way to handle gas when it is traveling at high velocities?
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Document ID: 8F76FD42

Electronics In Orifice Measurements
Author(s): James H. Griffeth
Abstract/Introduction:
Electronics in Orifice Measurement has only recently become more prevalent for on-site use. When gas was inexpensive the need for accurate measurement was not there. Historically, mechanical circular charts have filled the need to record flows, pressures and temperatures. But today we in the gas measurement business have seen an ever increasing demand to know what the true volume is at the site. With this demand comes electronics in the form of transducers and flow computers. The purpose of this paper is to make you- the field measurement operator- more aware of electronics and how it relates to our future field measurement systems. Over the past few years it has been more practical to use electronic systems to duplicate the control effects that can be produced with pneumatics. With the refinement of solid state electronics to the commonly know Integrated Circuit (IC) came the advantage of lower cost and higher reliability. In addition to the lower cost and higher reliability, the electronics has the advantage of almost instant transmission of signals to remote locations, and the signal is easily adapted to a variety of control systems. Customers of these systems have realized a quick payback of lower operational costs and real time data.
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Document ID: 6AE6F761

Fundamentals Of Positive Displacement Meters
Author(s): Giles m. Crabtree
Abstract/Introduction:
The first gas company in the United States, 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, its charge for gas service beyond the pocket-book of the majority. By comparison, the New York Gas Light Company founded in 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. The pattern of operation used by this New York company was quickly copied by other companies throughout the east coast, including the Baltimore company. Seeing the success in New York, businessmen formed new gas companies in Albany, Boston, Philadelphia, New York, etc., and the new industry in the United States began to flourish.
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Document ID: A3926E8D

Fundamentals Of Orifice Recorders
Author(s): Kenneth P. Cessac
Abstract/Introduction:
This paper will provide Information for use in selecting an orifice recorder. What is an orifice recorder or sometimes referred to as an orifice meter? The term orifice meter is used to mean everything from the orifice meter gauge recorder to the entire meter station. The American Gas Association defines the orifice meter as the complete measuring unit comprised of primary and secondary elements. The orifice meter tube and connection fittings are considered the primary measuring element. The instruments used to record the variables if the stream flowing through the orifice tube are considered the secondary elements. Some of the secondary devices used with orifice measurement are differential pressure recorder, static pressure recorder, flowing temperature recorder, and any other required recordings such as specific gravity and heating value.
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Document ID: EF2A7F7C

Gas Contract Interpretatiow
Author(s): John D. Howard
Abstract/Introduction:
As measurement people we will look at various contractual statements that may or may not be in every contract. I am not an attorney but remember this, most attorneys are not measurement people. We - will mean measurement people in this discussion. We will find many areas in the contract that do not pertain to our responsibilities in fulfilling this contract.
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Document ID: 942FED88

Calculation Of Gas Lost Due To Breaks, Ruptures, Or Third Party Damage
Author(s): Alvin C. Casto
Abstract/Introduction:
The increasing value of natural gas in recent years has placed greater emphasis on the use of a good method for the calculation of gas lost due to various instances. This paper will deal with the basic methods used by CNG Transmission Corporation for the calculation of gas lost due to line breaks or ruptures. There are several equations that may be used for this calculation. The basic equations and the conditions that indicate their uses are outlined below.
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Document ID: B6CA2FB7

Gauges And Dead Weight Testers
Author(s): Leo R. Lombardo
Abstract/Introduction:
What is an Inch of water? The correct answer to this question has taken on increased importance with the demand for better accuracy and the introduction of digital pressure indicators. For example, lets assume that you have just received your new digital pressure indicator and you decide to verify its accuracy. The manufacturer claims 0.1% accuracy at 100 inches of water. You set up a test using a deadweight tester and a water manometer. After placing a 100 inch of water weight on the deadweight tester, you record a reading of 99.8 inches of water on the digital pressure indicator and 100.3 inches of water on the manometer, Which Is right? The answer to this question will be evident after the following discussion of manometers and dead weight testers and their relationship to digital pressure Indicators. I will also include a discussion of accuracy and resolution as it applies to digital pressure indicators.
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Document ID: 57005501

Design Considerations For Orifice Meter Tubes
Author(s): Kenneth E. Embry
Abstract/Introduction:
The most widely accepted device for the measurement of natural gas and other fluids is the orifice meter. The primary element of the orifice meter is the orifice plate and orifice meter tube consisting of the orifice fitting, or flanges, adjacent piping, and flow conditioner or stra ighten ing vanes. The properly des igned meter tube should follow the guidelines for manufacture as established by the American Gas Association (AGA) Report No. 3 or American Nat ional Standard/American Petroleum Inst i tute (ANSI/API) Report No. 2530, herein referred to as AGA #3. This paper will address the tolerances, design, and meter tube inspection according to the guidelines of AGA #3.
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Document ID: 591D2072

Operational Procedures Of Electronic Chart Processor
Author(s): Chuck Gray
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. The Chart Processor computes and prints (for each chart) the chart extension ( HP), average pressure and flow time. It also stores and prints batch totals on command.
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Document ID: E5C9C7B7

Chart Auditing
Author(s): Bonnie L. West
Abstract/Introduction:
Columbia Gulf audits not only stations that are input points directly into our own pipeline, but offsystem locations for Columbia Gas Transmission Corporation as well. These locations are audited on a monthly, semi-annual or annual basis. The criteria, set up by management, for determining audit priority are as follows: 1) Locations where Columbias share of gas is 25 MMcfd or greater are audited monthly. 2) Locations where Columbias share of gas is 2 MMcfd - 25 MMcfd are audited semi-annually. 3) Locations less than 2 MMcfd are audited annually. All locations are reviewed twice a year and an update is done to conform to the above criteria. At present, we are auditing 12 locations monthly, 30 semi-annually and 200 annually.
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Document ID: 11E3D909

Mikeing And Inspecting Meter Tubes
Author(s): Lonnie R. Grady
Abstract/Introduction:
Gas prices are once again on the slide. Most companies, both producers and transporters, are looking for ways of cutting overhead. Measurement is an area that is often one of the first to suffer. I agree that cost consciousness is important and some cuts in measurement services may be justified. An area that should not be cut is the inspection of meter tubes. This paper will attempt to present the methods used to insure that meter tubes meet ANSI/API 2530 (AGA3) requirements.
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Document ID: 8C7E5085

Basic Principles Of Odorization
Author(s): J. T. Johnson
Abstract/Introduction:
The detection of natural gas leakage has long been a concern to the natural gas industry, but never more so than today. Increased pub lie awareness of safety and huge increases in the cost of product liability litigation has resulted in a greater focus on gas odorization. While odorization may be one of the smallest activities in the distribution of natural gas - NONE IS MORE IMPORTANT!!!
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Document ID: 981CA386

Light Hydrocarbon Measurement
Author(s): Gregory C. Riddick
Abstract/Introduction:
Light hydrocarbon liquids, for purposes of this pajper, consist predominately of the following components: ethane, propane, butanes, pentanes, hexanes and heavier paraffinic hydrocarbons. The liquid may be ccHnposed of a large percentage of one of these types of molecules, as in the case of specification grade propane product, or they may be a mixture of all these molecules, as in the case of unfractionated natural gas liquid (NGL) mix. Additionally, other components, such as olefins and contaminants, are also in the liquids, but they are present in a leaser percentage. Measuranent of light hydrocarbon liquids is more difficult than the measurentent of crude oils and refined products for a number of reasons. First, they are of low viscosity and have very poor lubricating properties. Secondly, the f*iysical properties vary widely as their composition varies. Additionally, their physical properties are dramatically different under different temperature and pressure conditions.
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Document ID: 66F2D594

Overall Measurement Accuracy
Author(s): E. H. Jones, Jr.
Abstract/Introduction:
The accuracy of oil field measurements varies from a few tenths of one percent to hundreds of percent. For example, a LACT unit will generally provide high accuracy measurements of a custody transfer oil flow while production allocation measurements sometimes are very inaccurate. The level of obtainable accuracy for a given measurement effects many parties other than the responsible measurement technician. Sales personnel, auditors, and reservoir engineers all must concern themselves with measurement accuracy of petroleum products.
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Document ID: 4B167DF7

Determination Of Specific Gravity By Various Methods
Author(s): E. D. Woomer, Jr.
Abstract/Introduction:
This paper deals with the determination of specific gravity via various methods and pieces of equipment. Also covered are definitions, relationships, and effects of specific gravity. The information presented herewith is applicable to United Gas Pipe Line Co. and conforms to accepted standards of the natural gas transmission industry.
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Document ID: AD509C62

Unaccounted-For Gas
Author(s): Christopher J. Glaeser
Abstract/Introduction:
The unaccounted-for figure can be either a positive number (more gas was purchased than sold) or a negative number (more gas was sold than purchased). In either case, it is important to determine what factors are contributing to the unaccounted-for gas and eliminate them. The reasons are economics and safety. Economically, unaccounted-for gas represents lost revenues that are not recoverable. It is gas purchased from a supplier but not sold to a customer (positive unaccounted-for gas). The other reason that we are interested in unaccounted-for gas is public safety. Leakage, third party damage and gas theft contribute to unaccounted-for gas that can effect the safety of our customers.
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Document ID: 227E8D18

EC0NOMICS Amd Justification For Electronics In Gas Measurement
Author(s): Brad Merlie
Abstract/Introduction:
In recent years, an increasing number of natural gas production, transmission, and distribution companies have begun to move away from the time honored means of recording gas flow information on paper charts. While the heart of most custody transfer measurement installations remains the meter tube/orifice plate combination, the use of microprocessor based electronic flow measurement (EFM) devices to record metering data is increasing at a rapid rate. These devices are being used to gather flow data on site, and calculate and store volumes based on AGA-3, AGA-7, NX- 19, and/or AGA-8 equations. Depending on the manufacturer, data can be stored at intervals from one minute to one hour and as much as one year of hourly data can be maintained in the EFM devices memory, The data can be collected on site with a small hand held terminal or laptop computer, or can be retrieved remotely through the use of a computer and a communication link to the remote location.
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Document ID: 73F7C5FE

Safety Relief Valves
Author(s): Gary B. Emerson
Abstract/Introduction:
Without going into the many specific formulas used in sizing safety relief valves, we will review the basis for various types of safety relief valve sizing situations. Recognizing that no one style of safety relief valve is suitable for all types of services, we will discuss the four basic types - weight loaded conventional direct spring operated balanced bellows, direct spring operated and pilot operated (piston type and diaphragm types) - and discuss various advantages, limitations, possible pitfalls, and specific applications of each. The basic purpose of a safety relief valve is to prevent system pressure from exceeding some predetermined limit, according to the service and applicable code. Normally the system pressure is not allowed to exceed the maximum allowable working pressure (MAWP) of the pressure vessel or pipe, plus an allowable overpressure.
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Document ID: 633DA521

Chart Editing And Integration
Author(s): Gary P. Menzel
Abstract/Introduction:
The title assigned to us for this presentation may iirply 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 conpanies operations which prevents the application of a single procedural formula to everyone, and we will make no atterrpt to do so. However, 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.
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Document ID: 6391D471

Fundamentals Of Gas Turbine Meters
Author(s): Charles R. Allen
Abstract/Introduction:
The gas turbine meter is only one of many types of meters that are used to measure natural gas. While each type of meter, each with its own design, has a particular application for which it is well suited, the gas turbine meter is one of the most versatile due to its high accuracy, wide rangeability, and moderate cost. In the gas industry today there are basically two types of meters that are in widespread use. These two types of meters are based on different physical principles and are classified as positive displacement and inferential.
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Document ID: A46B202A

Electronic Chart Integrators
Author(s): Bryan Billeaud
Abstract/Introduction:
In the natural gas industry, measurement and calculation of gas volumes have long been accomplished through the use of orifice meter chart records. Machines which make the calculation from these records are a common sight to most companies involved in gas measurement. Electronic equipment especially, have brought about substantial improvement to measurement and calculations due to their ever increasing speed, accuracy and mathematical abilities. There are many variables and methods used in the volume calculations generated from these chart records. One important consideration is the pressure extension. The pressure extension is derived directly from a chart record. It is computed from two independent curves on the chart which depict the pressure, in psi, found in an orifice meter tube and the differential pressure, in inches of H2O, of the opposite sides of the orifice. In accordance to the Bernoulli theorum, these two curves are considered as continuous records over a specified period of time.
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Document ID: 6275AAAE

H2S Detections And Determination
Author(s): James W. Canterbury
Abstract/Introduction:
Hydrogen sulfide (H2S) and total sulfur, in varying amounts, are found in almost all natural gas fields. In some cases, it is so small that the product is referred to as sweet gas. Many fields, however, produce sour gas, which is a gas with an H2S and total sulfur level high enough to require its removal or sweetening. Several methods are available to do this sweetening but, that is a separate subject and not a part of this paper.
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Document ID: 9B6169F7

Gas Measurement By Insertion Turbine Flow Meters
Author(s): B. J. Kemperman
Abstract/Introduction:
There are a number of different types of insertion devices available for gas measurement. They include pi tot tubes, vortex shedding meters, target meters, thermal dispersion meters and insertion turbine meters. What all these meters have in common is that (with the exception of the multiport averaging pi tot tube) they make a measurement at one point in the pipeline cross section from which the total flow through the pipeline 1s Inferred. Hence, if reasonably accurate measurement is required, it is important that such devices be inserted to a point in the pipeline where the prevailing flowing velocity is representative of the average of all velocities in the pipe. All insertion meters are averaging devices and must be viewed as such.
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Document ID: 2694D4B6

Application Of The Annubar Measurement In Gas Production And Processing
Author(s): Darnell 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 yood and accurate and frequently even better. Economic pressure encourayes the emerLjence of better all-around devices, with greater reliability and accuracy. These and other factors have brought to the fluid flow measurement industry the Multiport Averayiny Primary Flow Measurement Device. This refined version of the basic pitot tube, the same as the orifice and other head-type 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, includiny a simple desiyn, with equal or better performance for fluid flow measurement and process control applications.
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Document ID: DA45D2A2

Trouble Shooting Triethyleke Glycol Dehydrators
Author(s): Jerry Carson
Abstract/Introduction:
The dehydration of natural gas with glycol is accomplished by contacting-the gas with concentrated glycol (usually triethylene glycol with less than 1% water). The water vapor in the gas is absorbed by the glycol, diluting the glycol.. The diluted glycol then flows to the reboller where it is reconcentrated to the original concentration. A schematic of a typical glycol type gas dehydration unit with six bubble cap trays, an integral inlet scrubber and a glycol tialanced pump is shown in FIG. 1. This schematic includes a flash separator (Pump Gas Separator) which is in many cases an optional item. Wet gas enters the scrubber section through the wet gas inlet nozzle. In this section, entrained liquids are separated from the gas ana are removed from the system by the action of the liquid level controller on the distillate dump valve. The gas flows upward through the mist extractor and hat tray into the contactor section of the vessel. As the gas flows upward from tray to tray it is brought into contact with the glycol on each tray. The glycol absorbs the water vapor from the gas and the dry gas passes upward through the mist extractor and through the glycol to gas heat exchanger to the dry gas outlet nozzle.
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Document ID: 971F25C9

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 a electrical signal.
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Document ID: 086371DE

Field Inspection And Calibration Of Measurement Instruments
Author(s): Daniel R. Fulton
Abstract/Introduction:
Weve been told over and over again that the meter is the cash register of the natural gas industry. Thats certainlytrue, and while the meter itself must adhere to certain accuracy and performance standards, the instrument used in conjunction with the meter should be thought of in the same manner. That is, overall accuracy of the meter set is dependent on how well the meter and the instrument are maintained. This paper outlines practical things to consider in the care and feeding of measurement instruments used with positive displacement and turbine meters. Three basic types of instruments will be covered: volume recorders, mechanical correctors and electronic correctors.
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Document ID: 45F920C8

Electronic Vs-- Mechanical Correcting Devices
Author(s): Richard J. Ensch
Abstract/Introduction:
Metering devices measure natural gas at line conditions. Gas volumes vary with changes in pressure and temperature. Base conditions provide a common reference for measuring gas, and any variance In pressure or temperature requires a calculation to correct the gas line volume to base volume.
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Document ID: 5775F751

New Ideas In Measurement Real Time - A Measurement Perspective
Author(s): William E. Wickman
Abstract/Introduction:
The natural gas pipeline industry working environment has changed dramatically over the last decade. The complexity of transactions handled today 1n the natural gas industry has increased phenomenally and the means of handling gas both physically and contractual ly is in a state of tremendous flux. Essentially New Ideas In Measurement have not been manifest in the equipment employed to measure and monitor natural gas but rather 1n the strategies employed to satisfy the demands of our rapidly changing environment not applied sciences, but rather conceptual theologies. Hence, we will not look at the technological strides made in new and exotic equipment, but at the concept of how companies are grappling with the conceptual changes in this new era of the natural gas pipeline industry.
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Document ID: 9F8BE1E2

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: 6B5026CE

Field Experience With Composite Sampling Of Natural Gas
Author(s): Lonnie R. Grady
Abstract/Introduction:
For many years measurement technicians and measurement departments were concerned only with MCF measurement. Gas composition was not critical and samples we re only occasionally taken. The gas industry changed and the MCF has been replaced by the HHBTU. Accurate analysis are only possible if representative samples of the flowing streams are collected. The best wav to do this is with a composite sampler. This paper addresses the selection, set up, operation and maintenance of composite samplers.
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Document ID: D42B3591

Training Field Measurement Personnel
Author(s): David E. Pulley
Abstract/Introduction:
Growth of the natural gas industry has increased not only in size and industrial importance, but in new and greatly improved equipment and technical advancements. With this growth, the duties and requirements of the employees in the industry have become numerous and more complex, demanding much more information and knowledge of the task to be performed. The field measurement personnel are no exception. Today, a good meter man is, or should be, a skilled technician, competent to deal with the large number of instruments and devices now used in the industry. He should already have or acquire, a good working knowledge of the underlying principles and theory of measurement. Today a field meter man is actually performing his role as a field engineer in hydrocarbon measurement whether or not this is designated.
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Document ID: EA69669F

Regulatory Commission Safety Evaluation And Training
Author(s): Carl Nordstrand
Abstract/Introduction:
In 1970, the Railroad Commission of Texas began enforcing the Federal Natural Gas Pipeline Safety Act of 1968. These standards are published in the Federal Register, (A9 CFR 192). A copy of these rules along with additional State safety rules can be obtained from the Transportation/ Gas Utilities Division of the Railroad Commission of Texas in Austin. Actually Texas has been regulating gas suppliers since 1920 when the legislature passed the Cox Act placing gas pipeline operators under the control of the Railroad Commission of Texas for rate determination. The first pipeline safety rule occurred in 1937 and required operators to odorize gas after unodorized gas was blamed for the explosion at the Consolidated School in New London that killed 293 children and teachers.
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Document ID: BE23AE83

Btu Measurement In Natural Gas Using Process Gas Chromatography
Author(s): P.E. Kizer, W.E. Sund
Abstract/Introduction:
Process gas chromatography is a laboratory analytic method that has been adapted for continuous, online measurement of many components. These components riust be capable of being vaporized at reasonable temperatures. Most applications for gas chromatography are on light hydrocarbons, for instance, natural gas. Gas chromatography is a logical extension of other forms of Chromatography. All chromatography traditionally uses a mobile phase (gas or liquid) that pases over a stationary,phase (some solid or fixed liquid) to obtain the separation of mixtures of components.
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Document ID: B78D9F16

Fundamentals Of Orifice Metering
Author(s): m. J. Sergesketter
Abstract/Introduction:
This paper will provide information for use in selecting, applying, and checking the orifice metering system, with emphasis on gas measurement. The primary reference for mechanical tolerances of the orifice meter tube, plate holder and plate is American Gas Association Report No. 3, Orifice Metering of Natural Gas, published as ANSI/API Standard 2530. Much of this information is also published in a simpler, condensed format by orifice meter manufacturers. An excellent reference is Singer American Meter Division Handbook E-2.
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Document ID: 4F63465C

Water Vapor Determination And Effects On Gas Measurement
Author(s): Douglas E. Dodds
Abstract/Introduction:
The determination and the effect of water vapor on gas measurement is of importance to the gas pipeline industry because of the necessity for accurate gas measurement and for the maintenance of quality control. The following discussion covers typical methods which are used by the gas industry for water vapor determination. Each of the dew point instruments discussed use a specific method for water vapor measurement, and all are designed for use as either portable or fixed location instrumentation. In addition to a discussion of the typical methods for water vapor determination, the effects of water vapor on gas volume and heating value measurement is reviewed. The determination of the water vapor content within a gas pipeline system is essential for the maintenance of quality control.
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Document ID: 4466ABD9

Determination Of Calorific Values Of Natural Gas By Combustion Instruments
Author(s): Robert Van Meter
Abstract/Introduction:
Calorific value is a way of defining a quantity of gas in terms of heat per unit volume. The units most often used in this country to specify calorific value are BTU and cubic foot. The BTU is defined by Websters Dictionary as The quantity of heat required to raise the temperature of one pound of water one degree Falirenhelt at or near 39,2 F. There are two methods of determining ISTU value which require that the fuel be burned as part of the measurement. The Cutler Hammer calorimeter produces BTU values by measuring the temperature of a volume of air, heating the air by burning a volume of gas, and measuring the temperature of the air again. The temperature rise of the air is proportional to BTU and is recorded on an analog atrip chart or digitally on a printer. Another method of BTU measurement is based on the stoichiometric principal. Both the Precision Measurement instrument and the Honeywell analyzer implement tlris principal of measurement.
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Document ID: DF17583D

An Update On The Gri Metering Research Facility At Southwest Research Institute
Author(s): Robert J. Mckee
Abstract/Introduction:
Within the United States, some 17 trillion standard cubic feet of gas are produced, transported, and distributed to customers each year. This gas must be metered several times as it is purchased and resold by various companies, and finally to the end user. It is essential that the metering of gas flows be accurate, reliable, and efficient. The goal of the Metering Research Facility (MRF) program, sponsored primarily by the Gas Research Institute (GRI) and conducted by Southwest Research Institute (SwRI), is to improve the technology for gas flow measurement at field installations where the business of buying and selling gas takes place. Significant changes within in the gas industry in recent years have placed more stringent requirements on metering accuracy and repeatability. As these changes take place, it is necessary to evaluate new technologies under carefully controlled field equivalent conditions to meet industrys needs of identifying and quantifying systems effects on accuracy and economic effectiveness of the measurement system. The current needs of the gas industry in the area of metering are identified by the American Gas Association (A.G.A.) Gas Measurement Plan (Ref. 2).
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Document ID: B8399385

Field Testing By Transfer Proving
Author(s): Ronald L. Cawlfield
Abstract/Introduction:
There currently exists three types of field proving equipment for testing large diaphram, 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 Cri ti cal flow proving a bl ower i s not necessary.
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Document ID: 61480484

Fundamentals Of Energy Management
Author(s): Richard L. Howard
Abstract/Introduction:
The most precise method of managing energy in any form fron any source is direct, ie., the continuous measurement of the associated variables. In the natural gets industry, instrumentation exsists that will directly measure natural gas energy as delivered. At this time this instrumentation is under field test and is not comercially available.
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Document ID: 90EAB1DC

Computer Applications To Chart Processing
Author(s): Ted J. Glazebrook
Abstract/Introduction:
Most of us are familiar with the orifice meter and the orifice chart. We recognize that the chart is the key to determining the amount of gas used or produced. However, somewhere between the meter and the volume statement the information on the chart must be interpreted and calculated. It is important to bear in mind that the orifice chart does not contain all the information necessary for that final volume. Gas measurement would be quite simple if all we had to do was go into the field, read a little black box, assign a monetary value to the amount and then send a check or a bill. Unfortunately, there is no single instrument which can measure all of the different types of information needed to calculate a volume or an MMBTU value. Some of the information which is required and the associated instruments used to capture that data are:
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Document ID: 142758B5

Problems In Offshore Gas Measurement Problems And Solutions Encountered In Offshore Measurement
Author(s): Mikel Gaston
Abstract/Introduction:
The next 45 minutes will address some of the major problems and solution encountered with gas measurement on offshore platforms in the Gulf of Mexico. The presentation will also stress the importance of competent measurement personnel and their roles in assuring that accurate measurement occurs. Slides that identify actual equipment installations, safety hazards, weather conditions, and logistics problems will be presented.
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Document ID: 12394324

Effects Oh Entrained Liquid Oh Orifice Mkasuhement
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 flow are based on the assum.ption that the gas is dry. This condition is rarely the case in field measurementE. The A.G.A. Committee Report No. 3j (1), 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. Schuster, (2) has conducted full range field tests of gas-liq.uid mixtures at 60O and 1,000 pounds per square inch pressure using the orifice meter. In these tests a it-inch meter run was used to measure the dry gas. After this measurement, water and/or distillate in varying amounts was introduced and the two-phase stream was then measured first through a It-inch meter run and then by a 3-iDch meter these tests covered liguid-gas ratios up to 60O barrels of liquid per million cubic feet of gas. A cubic foot of gas in this paper is measixred at 1U.65 pounds per square inch absolute and 60 Fahrenheit.
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Document ID: F2071F11

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.
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Document ID: 5DE335F8


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