The Pros And Cons Of Rotary Meters
Author(s): John H. Heath
Abstract/Introduction:
The first positive displacement rotary gas meters were built around the year 1920 by the PH & FM Roots Company and the Connersville Blower Company, both located in Connersville, Indiana. In 1966 this gas meter operation was renamed Dresser 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. The operating principles for each of these three meters are depicted and explained in Exhibit #1.
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Document ID:
DD5D6525
Production Measurement With Rotary And Turbine Meters
Author(s): Craig A. Caldwell
Abstract/Introduction:
Production measurement offers some unique problems not particularly found in distribution or industrial measurement. There are four common methods of measuring production gas: tfie orifice, diaphragm, rotary or turbine meter. All of these methods work well under certain circumstances and are inappropriate under some other conditions. This paper will review installation considerations and maintenance procedures for two of these metering devices, the rotary and turbine meters.
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Document ID:
38F454BE
Control Valves For Large Volume Regulation
Author(s): Terry Buzbee
Abstract/Introduction:
Although gas pressure regulators dominate much of the control applications in the Gas Distribution and Transmission Industry, they are limited to applications with small flow requirements. These applications are numerous in any Gas Distribution System and include commercial, industrial, and domestic service, farm taps, and district pressure control. Large volume gas pressure control is less frequent but necessary in many gas industry applications Including city gate stations, some district stations, and gas transmission. Control valves offer much more capacity, as well as other advantages, to meet these large volume gas pressure control requirements.
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Document ID:
E47AA6A8
Digital Flow Totalizer
Author(s): Russ Arslanian
Abstract/Introduction:
With the present trends in the cost of natural gas, it is easy to see where the measurement and accou nting for gas will receive much more attention in the years ahead. When the price of natural gas was low it was difficult to justify the use of good measuring equipment however, since new contract gas prices are sometimes more than 10 times earlier rates there is a definite need for more accurate and convenient methods of determining gas volumes. Until recently very few innovations have transpired with the mechanical chart recorders and people have accepted the traditional problems of clock malfunctions. non-inking, changer errors, and the lengthy lag time between time of actual gas flow and time of reporting.
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Document ID:
0EAECA8D
The Basics Of Pressure Pulse Proving
Author(s): William S. Follin
Abstract/Introduction:
A discussion of the theory and practical application of Pressure Pulse Proving equipment to the gas meter shop operation. It has been learned through extensive testing of both 3 and 4 chamber positive displacement gas meters that the energy absorbed to operate a meter has a fixed wave form for each particular meter. This wave form represents differential pressure across the meter. Also, it has been determined that this waveform is extremely repeatable from one cycle of the meters mechanism to the next. Each cycle of the meters mechanism represents a portion of a cubic foot of gas by design. If a particular meter required 9 revolutions per cubic foot, then one revolution of a perfect meter would be equal to 1/9 of a cubic feet.
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Document ID:
34EDF7C0
Basic Gas Laws
Author(s): E. O. Rossbach
Abstract/Introduction:
Gas measurement is the determination of a volume of gas at a particular temperature and pressure. The measurement should be as accurate as possible, making use of the best data and techniques available. The gas quantity is usually expressed in cubic feet at some specific temperature and pressure. As the price of gas, as well as other forms of energy are rapidly increasing, the accuracy of measurement is becoming more and more important. In order for a measurement man to have a better understanding of the principles of gas measurement, a basic understanding of the laws of gas behavior is a must. Natural gas is made up of a mixture of various gases. The mixture follows certain rules when subjected to pressure and temperature changes. In order to understand the behavior of this real gas, we should first learn something about the behavior of an ideal gas. The kinetic theory of gases is a good starting point.
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Document ID:
D2B65475
Wide Range And High Accuracy Measurements For Orifice Metering Using Microcomputers
Author(s): Edgar E. Buxton
Abstract/Introduction:
New software packages for microcomputers offer measurement accuracy improvements and a reduction in calibration manpower. When combined with Auto- Zero hardware these microcomputer systems also offer reduction in measurement errors due to transmitter zero shift. Signal amplification is used to reduce readout error at low differential pressures providing an analog to digital resolution ottO.006 inches (less than 1%of reading at 1 inch differential from a 100 inch span transmitter). Profiling provides for accurate instrument calibration and linearization with a minimum of user effort. These features are expected to enable one differential pressure transmitter without a temperature controlled enclosure to provide more accurate flow measurement results than the current system designs using two transmitters in a temperature controlled enclosure.
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Document ID:
F4006F77
Current Research Projects On Orifice Measurement
Author(s): E. L. Upp
Abstract/Introduction:
For measurement of high pressure, high volume natural gas, the orifice meter remains the predominant choice for flow measurement. AGA-3, which Is the standard upon which the orifice measurement is based, makes this statement in its forword: This is not a final report, but is made with the understanding that the committee will continue its analytical studies of data already developed. The committee also fully expects that it will be necessary for it to conduct further experimental work of its own. This will make necessary one or more supplemental reports, in which data will be summarized and the mathematical principles announced, which are the basis for the report, and such modifications and extensions will be made as additional data and further study may require.
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Document ID:
AA09125F
Monitor Regulators And Relief Valves
Author(s): Don Day
Abstract/Introduction:
This paper is a general discussion of the philosophy behind the use of monitors for overpressure protection as well as an analysis of the types of equipment that can be used. Whenever a device is used to feed gas from a high pressure system to a low pressure system, there is alway the possibility that the device will fail in a manner which will allow the pressure to go to a dangerously high level. We must always assume that the pressure regulator could fail in the wide open position. There are two popular methods of providing protection against overpressuring the system downstream of a failed regulator. One method is the simple installation of a properly sized relief valve however, this method is falling into disfavor because a quantity of gas is lost whenever the relief valve operates. The other method is the use of a monitor regulator and this method is becoming more popular because no gas is lost.
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Document ID:
2EAC9D4C
Operation And Maintenance Of Chart Processing Equipment
Author(s): T. Y. Tramel
Abstract/Introduction:
With the ever increasing cost of natural gas, more emphasis is being placed upon the speed and accuracy of all gas measurement systems. My objective is to present you with an overview of the operations and maintenance of the state-of-the-art equipment currently used in gas measurement offices. I will illustrate three major points of interest which include: a general definition of the equipment, operational procedures, and preventive maintenance routines.
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Document ID:
7D188023
Determination Of Water Vapor In The Gas Stream
Author(s): Ken Lewis And Curt Kein
Abstract/Introduction:
I am sure that most of you are very familiar with the subject of determining dew points however, I would like to present this paper with the thought that perhaps some portion of the paper can be useful to some of you in our industry. The accuracy of determining the dew point cannot be overemphasized. Transmission companies usually specify by contract a maximum allowable water content when purchasing dehydrated gas. The maximum amount allowed by most purchasers is usually 7#/MMCF at 14.73 PSIA and 60F. Transcos statement of basic practice is to maintain a moisture level of less than 6# of H20 per MMCF in our main lines and sales points. Therefore, our moisture monitoring is critical and requires more attention.
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Document ID:
FB8B5EC8
Design Of Operation Of District Regulator Stations
Author(s): Robert T. Burrows
Abstract/Introduction:
The purpose of this paper is to point out some of the more important design factors that must be considered when designing distribution regulator settings. In discussing the many factors considered by the Columbia Gas of Ohio, a general overview will be given of distribution regulation design standards currently being used. These design examples and specifications are only intended as a guide. These specifications can be compared to your own distribution regulator designs, which out of necessity, must reflect the type of distribution system you have and your own Individual company policies.
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Document ID:
8FDDAA20
Plastic Meter Parts - How They Are Doing
Author(s): G. S. Verra
Abstract/Introduction:
How are plastic meter parts doing? The answer to that question is well, but not perfect. The inclusion of plastics in meters Isapartof an increasing use of plastics in a wide variety of manufactured goods. Let us first look at the use of plastics in general. The term plastic actually refers to a very wide variety of materials of varying characteristics. Over the last two decades, plastics have greatly increased in number, quality, and use. The techniques used in design and select plastic materials have developed so that the different characteristics of plastics are accounted for-such characteristics as creep, environmental stress crack resistance, thermal expansion and contraction, ultraviolet degradation, and resistance to softening when in contact with various chemical agents. The development of engineering techniques, improved plastics, and more complete information about the performance of those plastics has led to a rapid expansion in their use. Their use in gas meters, particularly the changes in the last decade, is a good example of that expansion. In gas meters, the plastic parts used are made from materials that have specific definable characteristics and have been engineered to perform in the environment and under the conditions of anticipated operation. In this report, I plan to review some of the significant changes that have been made and discuss how well the plastics have performed.
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Document ID:
E276872E
BTU/Water Vapor Content Adjustment
Author(s): C. W. Barllett
Abstract/Introduction:
In the natural gas industry, the term Btu/cf has recently become a hot subject. Mostly because of federal rulings on price adjustment, but probably as much because of people like you and me who have to try and solve the mechanics for obtaining our answer. A variety of definitions can be found to describe Btu, British thermal unit, but essentially, its basic meaning relates to heating value. The heating value of natural gas is usually determined by calorimetry or analysis. A calorimeter is a mechanical device designed to measure and usually record the Btu value, whereas the analytical method requires calculating the Btu value based upon the mol fraction or precent of the hydrocarbon compounds contained in the gas. The calorimeter, using the wet gas meter principle, saturates the gas with water vapor and the Btu value is determined on a wet basis. The usual chromatographic process used for determining the gas constituents normally eliminates water vapor content from the sample and the calculation is made on a dry basis.
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Document ID:
20043138
Operation And Calibration Of The Insertion Turbine Meter
Author(s): Michael E. Balch
Abstract/Introduction:
This differs slightly from the more familiar full bore turbine which presumes to measure the total flow of fluid in a pipeline. So why bother sampling the velocity measurement when the full bore measures the total flow? There are at least three very good reasons: 1. It is hot tappable into the line. Thus not requiring the flow to be shut down for eitheroriginalinstallationsor periodic maintenance. 2. It comes about as close as any meter can to being a universal meter. The identical meter can be hot tapped into line sizes 3 to 40 inches in diameter. The identical meter, with only perhaps a rotor change, can be used on both liquids and gases. 3. Thirdly, with the other two benefits is it also economically feasible? Not being affected by line size and being hot tappable into the tine allows the insertion type flowmeter to enjoy a flat cost whereas full bore meters increase in cost exponentially with line size.
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Document ID:
2D126507
Direct Entry Of Chart Data
Author(s): Robert D. Starr
Abstract/Introduction:
Gas measurement charts, along with their associated data, are processed in vast numbers daily throughout the gas industry. This information is processed by different means from one company to another. However, all companies share a common need for accuracy and speed in the handling of their gas measurement data. Texas Eastern has recognized the importance of efficient, accurate gas measurement techniques, both in the field and in the office, for some time. By employing equipment like micro chart processors and electroscanners, the Gas Accounting Section of the Measurement Department has been able to increase the number of charts processed daily without sacrificing accuracy.
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Document ID:
946D5D5C
Application Of Regulators For Proper Measurement
Author(s): William H. White
Abstract/Introduction:
In installations where both pressure regulation and measurement facilities are installed, measurement errors can occur as a result of poor pressure control. In any installation, the proper design, installation, and operation of pressure regulators is important for good pressure control and safe operations. Where measurement is installed also, these areas become more critical in order to obtain not only good control, but also accurate measurement. This paper is intended to describe those areas where regulator problems can affect measurement accuracies. It will alsoaddress those areas of design, installation, and operation that are important to obtaining good pressure control along with accurate measurement. Poor regulator performance will affect accurate volume measurement in the following areas - calculation of displacement, orifice and turbine meter volume inaccuracies in the orifice meter flow coefficient errors in fixed factor measurement, and errors in turbine meter index volumes. Each of these items are discussed below.
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Document ID:
6FC766F1
Developing Billing Adjustments
Author(s): Estell Harrell
Abstract/Introduction:
An ease of government price controls brought about the opening of new energy fields which previously were considered to be economically impractical. Inflation coupled with less government control increased the price tag on energy. In the 80s, the cost of natural gas will continue to rise and the highest degree of accuracy will be demanded of chart processing departments. Adjustments will play a more and more important part in Gas Measurement.
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Document ID:
027ECD81
Analysis Of Gas Measurement Recording Charts
Author(s): Iris King
Abstract/Introduction:
With Gas Measurement being the cash register of any gas company, the matter of chart analyzing is a very significant function in the gas industry. Charts must be analyzed to determine the completeness and accuracy of the recordings. In case of mechanical failure, estimates must be made as accurately as possible. Depending on what type of problem is indicated, the meter specialist or chart changer must be notified concerning any chart problems. The meter specialist handles the testing of the meters and the mechanical problems. The chart changer is responsible for changing the chart each time and filling out the back of the chart correctly.
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Document ID:
6C00A96C
Inspection, Maintenance And Testing Of Orifice Meters
Author(s): Kenneth E. Lamp
Abstract/Introduction:
The need of the gas industry to measure large volumes of gas at high pressure led to the development of the orifice meter. Nearly all of the early successful orifice meters were the mercury type. However, during the mid-forties, the first bellows meters were introduced to the gas industry as Dry Meters. It appears that the bellows or dry type of orifice meter is the most widely used today, but many measurement people feel that the mercury type of meter is the more accurate. Due to safety-problems inherent in the handling, cleaning and transporting of mercury, there has been a decline in the use of mercury gauges. Because of the very nature of large volume measurement, huge sums of money are involved therefore we cannot emphasize too strongly the Importance of the man in the field inspecting the orifice meter. An orifice meter is only as good as the care it receives. Accurate measurement requires: (1) properly designed facilities (2) accurate test equipment (3) a conscientious meter inspector.
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Document ID:
1CDFAB11
The Selection Of Plastic Parts For Gas Meters And Regulators
Author(s): John L. Esola, James F. Hrin
Abstract/Introduction:
Recent increases in the price of natural gas have caused gas consumers to place more emphasis on gas measurement accuracy. Gas meter and regulator manufacturers must therefore continually search for new ways to improve the performance of their products. These improvements might be in the form of a new mechanical device to be installed in a meter or regulator or simply the making of an existing part from a more durable or better performing material. One of todays more common methods of improving performance of gas meters and regulators is through the use of plastic materials. Properly applied, plastic materials can be usedfora wide variety of applications. Some of the important characteristics of these materials are: 1. Wide Variety of Materials and Properties 2. High Lubricity with Low Coefficients of Friction 3. Corrosion Resistant 4. Good Wear Characteristics 5. Lightweight 6. Can be Molded into Intricate Shapes to Perform More Than One Function 7. No Machining Operations.
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Document ID:
4C099BCA
Testing And Adjusting Large Capacity Meters In The Field
Author(s): Alvin C. Casto
Abstract/Introduction:
The operation of a meter is controlled by valves allowing gas to enter and exhaust from chambers in which there are movable pistons called diaphragms. The opening and closing of these valves is controlled by a mechanism actuated by the movement of the diaphragms. The proper time of valves opening and closing is determined by the construction of this mechanism. If each chamber admits and exhausts the same amount of gas each time its respective valve opens and closes, the volume of gas passing through the meter in one revolution is easily calculated by multiplying the volume displaced by one chamber by the number of chambers in the meter. It may then be determined how many revolutions are required for one cubic foot. A gear train is then designed to convert the revolutions of the meter to cubic feet and an index applied to record the total volume.
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Document ID:
B6F895F4
Chart And Mechanical Correction Devices For Displacement Meters
Author(s): Franklin J. Timperio
Abstract/Introduction:
All positive displacement meters measure gas in cubic feet at line pressure. Gas is bought and sold at a certain price for each 1,000 cubic feet as if measured by a meter at approximately atmospheric pressure. Therefore, when the gas is measured at pressures above or below atmospheric pressure, the pressure at which each cubic foot is measured and the factor for the pressure must be known in order to convert the quantity indicated by the meter into the quantity which would be measured at the base pressure which is approximately atmospheric pressure. Actual volume measurement displaced volume) is completely independent of the gas specific gravity, temperature and pressure but variations in gas flow is due to changes in pressure and temperature. Because of this, it is necessary to specify the pressure and temperature at which a certain volume is considered as standard these conditions are known as the base pressure and base temperature.
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Document ID:
B3A292C5
Microprocessor Based Supervisory Control And Data Acquisition
Author(s): Jim Russell
Abstract/Introduction:
The technology of SCADA remote terminal design Is at a very difficult time in its evolution. There is enough history to provide some tradition and de-facto standards. Yet, this history has been compiled with circuit components and concepts that are today completely obsolete. In the past, a remote terminal was simply a means of extending the master CPUs I/O to a remote location. The traditional functions are to: 1. Communicate reliably With the master 2. Provide secure field interface for a. Status/Alarms (contact closure) b. Meter Counting (contact closure) c. Analog Measurement (4-20 ma) d. Digital Control (contact closure) e. Analog Setpoint (4-20 ma) These traditional functions are important. In fact, without full and proper implementation of these functions there is no basis for a SCADA remote terminal.
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Document ID:
7B8258C0
Field Testing With A Transfer Prover
Author(s): John H. Heath
Abstract/Introduction:
The need for an accurate, reliable, and portable field transfer testing system has resulted from the growth of the gas industry. The growth has brought about the desire for better methods of field testing meters. There are presently available three methods for field testing meters: 1. Low-Pressure Flow Prover 2. Critical Flow Prover 3. Transfer Prover The low-pressure flow prover and the critical flow prover Involve the measurement of several variables which in turn may cause the compounding of errors before the final accuracy can be calculated. The transfer prover requires only the sensing of temperature and pressure differences between the prover and the meter under test. Results obtained from a transfer prover should be more accurate and repeatable and compare more favorably to the accepted standards of the bell and piston provers.
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Document ID:
F3716DF2
Fundamentals Of Flow Computers
Author(s): Robert E. Barnes
Abstract/Introduction:
The perspective of this paper is from a user, not a manufacturer or seller of flow computers. The content will be mainly for those who know very little about flow computers rather than for those who know a lot about flow computers, I believe that the tital Fundamentals of Flow Computers dictates this approach, A flow computer will be defined, describing it as a computing system and describing the individual basic parts: input devices, computer, and output devices. The flow formulas that it uses in its computations will be included.
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Document ID:
035BE091
Testing And Repair Of Large Capacity Diaphragm Type Displacement Meters In The Shop
Author(s): Frank m. Koch
Abstract/Introduction:
The year 1820 was probably the birth of large capacity displacement meters. It was the year that Samuel Crosby improved the revolving drum water sealed wet gas meter. This improvement in large sizes became known as the Hinman Drum. One of these meters was 16 feet in diameter and proportionately long. A size 16 station meter had 24 connections and a capacity of 173,000 C.F.H. at 1 in. differential and 215,000 C.F.H. at 1.5 in. differential. The weight of the meter was 95,000 pounds with an additional 136,000 pounds of water. Sprague Meter company is said to have made the worlds largest ironcase diaphragm displacement meter. The no. 20 meter weighed approximately one ton and was equipped with 6 connections. It has a capacity of 15,000 C.F.H. at Va in. differential and 32,000 C.F.H. at 2 in. differential.
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Document ID:
C05ACB56
Manufacturers Calibration Procedures For Turbine Meters
Author(s): Raymond Teyssandier
Abstract/Introduction:
Unlike the orifice meter, which has a meter coefficient established by dimensional checks, gas turbine meters require calibrations to determine their meter factor. Each gas turbine meter must be calibrated before leaving thefactory not only to establish its meterfactor but also to check whether or not it meets both the catalog specified values of linearity and repeatability over the range of flows. Why this must be done cannot be answered in an easy or simple fashion since turbine meters do not lend themselves to simple two dimentional fluid dynamic analysis (the problem is three dimensional). Furthermore, one must additionally factor in the fluid dynamic/mechanical interaction of the bearings (and in non-electrical metersthecounterdrivetrain). Rather than attempt to try to explain the why of calibrations this paper will consider how factory calibrations are conducted.
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Document ID:
5F016846
The Importance Of Accurate Measurement To Storage Deliverability
Author(s): Gregory W. Theirl
Abstract/Introduction:
Storage deliverability is taken to mean the rate at which gas can be withdrawn at a given book inventory of gas in storage. Determining and projecting meaningful deliverability information is an integral part of the planning and operating functions of a storage operation. It is the intention of this paper to focus on the importance of accurate measurement and its interrelationship with storage deliverability.
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Document ID:
B473BB20
Selection And Measurement Of Meter Tubes
Author(s): Homer H. Swarner
Abstract/Introduction:
In the gas measurement industry, the term primary element generally refers to the orifice plate, the orifice plate holding device, the meter tube, pressure taps, and straightening vanes. The meter tube, the third component of the primary element, consists of the inlet and outlet sections of pipe adjacent to the orifice fitting. The meter tube greatly affects the overall accuracy of the primary element therefore, careful attention must be given to its fabrication. Because of this, the manufacture of meter tubes, like that of orifice meters and orifice fittings, has become a considerable science. Meter tubes should adhere to the standards recommended in the American Gas Association (AGA) Gas Measurement Committee Report No. 3 (Revised 1969). Adherence to these standards will ensure control of the condition of gas flow adjacent to the orifice. Recommended standards contain specifications for inside condition and length of pipe sections adjacent to an orifice.
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Document ID:
819E939B
Operation And Maintenance Of The Cutler-Hammer Calorimeter
Author(s): A. F. Kersey
Abstract/Introduction:
This paper will touch briefly on the operation and Installation of the recording Calorimeter and cover in more detail the maintenance of the instrument. The recording Calorimeter is a gas burning device. The heat of combustion in the main burner is used to determine the BTU of the gas being analysed. Combustion is supported by primary and secondary air. There is 40% excess secondary air to assure complete combustion. When observing the flame, there should be no signs of incomplete combustion (carbon).
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Document ID:
9F9B1E1B
Fundamentals Of Instrumentation
Author(s): William I. Miller
Abstract/Introduction:
No matter how sophisticated instrumentation becomes in the 1980s, the fundamental building blocks will remain unchanged. With diversified requirements throughout the world, and often limited availability of resources to accommodate state-of-the-art products, analog instrumentation will remain an integral part of process control for many years. Instrumentation provides measurement, indication, recording, and control based on the specific requirements of each process. When selecting instruments, the variables to be considered include installation and production costs, desired operating efficiency, product quality requirements, materials utilized and associated costs, environmental conditions, government regulations, geographical factors, and traditional management philosophy.
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Document ID:
2F532354
Fundamentals Of Regulation
Author(s): Cindy Scott
Abstract/Introduction:
For all practical purposes, regulators used by the gas industry can be placed in either of two categories: I. Self Operated, or II. Pilot Operated. This categorizing of all regulators (plus all construction modifications) tends to be an over-simplification, but exceptions are rare. Lets examine each of them closely.
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Document ID:
C449042E
Diaphragm Meter Capacity Ratings At Elevated Pressures
Author(s): Howard W. Berghegger
Abstract/Introduction:
Through the years, the gas industry has been steadily improving, especially from a technological and product improvements viewpoint. Today, the gas industry has standardized on most applications, methods and definitions as compared to the knowledge possessed just twenty short years ago. Within the measurement field, two important areas are still open for discussion and at the discretion of the individual persons or companies operating within these areas. One is the lack of an industry standard definition for a standard cubic foot of natural gas and a second is the lack of an industry standard for diaphragm meter capacity ratings at eievated pressures. There are presently in use a minimum of ten different base pressures, each of which defines a standard cubic foot of natural gas. There are many different methods of gas measurement in use today-the three most common are diaphragm displacement meters, rotary displacement meters, and inferential meters.
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Document ID:
21D52E8B
Transfer Provers - A Comparison Of Commercially Available Types
Author(s): W. J. Tellska
Abstract/Introduction:
Transfer proving gas meters have been in use since large wet-type station meters were used to measure the volumes of gas made and supplied to distribution systems. In these cases, the transfer prover was nothing but a small portable wet-type meter approximately 3 foot in diameter. The test meter was transported to the location, filled with water to a calibrated level, and connected in series with the station meter. After a volumeof gas passed through both meters, a comparison was made to determine the accuracy of the large stationary meter. As the demand for large commercial and industrial gas meters increased, meter technology improved to the point where present-day gas meters and transfer prover master meters are light and easily transportable. Transfer provers are used today in shop applications to obtain flow rates greater than available from bell provers and in the field to test meters when it is not economically feasible to remove the meter and return it to the shop for testing.
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Document ID:
2FAEED1A
How To Take A Representative Gas Sample
Author(s): Thomas F. Welker
Abstract/Introduction:
Defined by the Gas Processors Association Publication 2166-68, The object of any sampling procedure is to obtain a representative sample of hydrocarbons from the system under investigation. Any subsequent analysis of the sample regardless of the test, is inaccurate unless a representative sample is obtained. Due to the wide variation in flowing streams and the components in these streams, the proper sampling techniques must be employed in order for the sample to be taken, transported, stored, and finally analyzed by some type of test device. The first factor that must be covered is the person chosen to physically take the spot sample, or install and maintain the sampling device. This person is the beginning of a successful sampling program. The final outcome of the sample operation will be determined by the efforts of this first link in the unbreakable chain of operations that must be performed without variances which can and will affect the outcome of the results obtained.
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Document ID:
FE9B62DA
Field Estimation For Orifice Meters
Author(s): Carl Freeman
Abstract/Introduction:
In order for the Appalachian area producer to achieve maximum gas output from his wells, it is very helpful to know as soon as possible if changes made with respect to the operation of the wells has been beneficial. Operating under these conditions, it is necessary for field personnel to be able to estimate production from an orifice meter chart. Field estimating can be done in two ways: 1.) Obtaining a general idea of production. 2) Obtaining an accurate measurement as is possible. The basic difference in the two methods is whether one reading is taken for each operating cycle, or several readings are used.
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Document ID:
F36A342C
Fundamentals Of Orifice Metering
Author(s): Jerry Paul Smith
Abstract/Introduction:
The orifice is one of the oldest known devices for measuring or regulating the flow of fluids. The Romans are credited with using it to regulate the flow of water to householders. However, the development of the orifice or orifice meter on which the purchaseof fluids may be based, took place in the early 1900s. According tothe Report of the Joint A.G. A.-A.S.M.E. Orifice Coefficient Committee dated November 1935, there were numerous research projects conducted on the flow of fluids through orifices during the nineteenth century. Just when and where a thin-plate orifice was first used in the measurement of fluids, particularly for sale purposes, has not been definitely determined, but it was probably before 1890. It was about this time that Mr. Forrest M. Towl witnessed orifice meters being used for measuring natural gas In the vicinity of Columbus, Ohio. These particular orifices had been installed and were being used at the suggestion of the late Professor S. W. Robinson of Ohio State University. In the early 1900s much work was done to develop the use of the orifice as a custody transfer device. In May 1924, the Board of Directorsof the Natural Gas Association directed its Main Technical and Research Committee to establish a new sub-committee to be known as the Gas Measurement Committee.
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Document ID:
E3C627D8
Selection Of Orifice Vs. Turbine
Author(s): James T. Jones
Abstract/Introduction:
The purpose of this paper will be to show the reasoning used for the selection of either orifice meter or turbine meter measurement for certain applications. There is no intent to imply that other types of measurement such as rotary or positive displacement meters should not also be given consideration for certain applications.
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Document ID:
E1F1706D
Large Volume Application For Diaphragm Meters
Author(s): John L. Esola
Abstract/Introduction:
The term Large Capacity Diaphragm Meters, as used by the gas distribution industry, refers to those diaphragm type meters with a capacity of 500 to 10 or 11,000 cfh of 0.64 specific gravity natural gas at a maximum of 4 oz. inlet pressure with no more than two inches water column differential pressure between the meter inlet and outlet at capacity flow. It also refers to rotary meters which also operate on the positive displacement principle.
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Document ID:
C3A776CF
Field Inspection And Calibration Of Turbine Meters
Author(s): Joseph L. Pond
Abstract/Introduction:
The recommended procedures to be followed during the periodic inspection of turbine meters in the field are detailed in manufacturers literature and in AGA Report #7. Generally, these procedures include a visual inspection of the meter mechanism and a spin-test. As stated in AGA Report #7, If the mechanical friction has not significantly changed, the meter is clean internally and the Internal portions of the meter show no damage, the meter should display no change in accuracy. If the mechanical friction has increased significantly, it would indicate that the accuracy characteristic of the meter at low flow rates has degraded. Note specifically that increased mechanical friction, as indicated by a significant decrease in spin time, initially affects the low flow accuracy of a turbine meter. This effect can be illustrated by reference to Figure 1.
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Document ID:
DCE0BAFC
Temperature Compensation Diaphragm Meters
Author(s): W. A. Thomas
Abstract/Introduction:
Temperature compensation of diaphragm meters was Introduced in 1957. A revolutionary concept at the time, years of experience have varified both the accuracy and value of temperature compensation for diaphragm meters. The development of internal temperature compensation for diaphragm meters was the result of a number of Influences. Both the value and the consumption of gas was increasing markedly during the 1950s. Heating loads were being added to existing cooking and hot water loads creating a seasonal variation not generally experienced before. A growing trend toward outdoor sets with the availability of synthetic diaphragms placed the meter in a varying environment. It is the environmental effects - greatest consumption when the weather Is coldest - that spurred adoption of temperature compensated diaphragm meters by gas distribution companies.
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Document ID:
6296C8EF
Wellhead Gas Conditioning Equipment
Author(s): G. Thomas Piper
Abstract/Introduction:
The purpose of this paper is to provide an overview of the process equipment used to condition natural gas. Equipmentapplication,function,description and problems will be examined. Gas conditioning consists of techniques and processes employed to remove undesirable liquid and/or solid components from the gas stream resulting in saleable natural gas. Regardless of Its ultimate use, natural gas. Regardless of its ultimate use, natural gas will need to be conditioned in one way or another to assure reliable flow from the well to a process plant or transmission pipeline. Basic gas conditioning processes include liquid separation, solids filtration, dehydration and gas heaters. Other selective type conditioning processes have developed over the years to condition gas which was previously thought of as unsaleable.
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Document ID:
FDA083F4
Market Area Analysis Of Unaccounted For Gas
Author(s): John E. Taggart
Abstract/Introduction:
It is often said that death and taxes are the two things each of us must accept as a fact of life. To those of us who work in the gas industry, unaccounted for gas may be added to death and taxes as the third unavoidable fact of life. Unaccounted for gas has been with us in the past, is with usnow,and will be with us in the future. However, I predict the concern about the levels of unaccounted for gas will increase in proportion to the escalation of gas prices at the burner tip. There was little or no concern when gas sold for 50*1 an mcf minimal concern at the 2.00 level increasing concern at the 4.00 level and I predict tremendous concern as gas reaches the 6-8 or 10 dollar level in the future. This concern will be expressed not only by our managements, but by regulatory Commissions and Consumer Advocates as well. The disallowance of the gas purchase costs related to what a regulatory commission deems excessive unaccounted for gas is a distinct possibility.
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Document ID:
216D5C53
Effects And Control Of Pulsations In Gas Measurement
Author(s): Robert H. Pish
Abstract/Introduction:
The undesirable effects of pulsations on gas flow measurements made with orifice, turbine and vortex flow meters indicate the need for methods to effectively control pulsation. Several practical techniques for the prediction and control of pulsations are discussed and illustrated in this paper. These techniques make it possible to design gas flow measurement facilities which minimize the effects of pulsation.
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Document ID:
E8355029
Theory And Operation Of Pneumatic Controllers
Author(s): Robert H. Welker
Abstract/Introduction:
It is important for gas men working with pneumatic controllers on a day to day basis to really understand them. Not to understand the controller can be a continual burden to the operator, In addition to presenting circumstances for an operation of lower quality than generally desired. Therefore, the objective of this paper is to try to help develop an understanding and attitude toward the controller that is absolutely essential to high quality gas control. When we speak of controllers, we want to differentiate them from the pilot type of control. In general terms, a pressure controller is a separate unit from the control valve and it will have some constant bleed to atmosphere. Again, in general terms, we think of pilot controls as being an Integral part of the regulator and having a downstream bleed. What is the difference in these two types of control? One important difference is the fact that the pilot system can never match the efficiency of a pneumatic controller because it is the controller which can utilize reset, the function that keeps our process on set point regardless of changes in upstream pressure or load conditions. Furthermore, it is the controller that has a very wide range of sensitivity adjustments so that it can be tuned to fit every type of load.
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Document ID:
63B8EBD6
Ball Valve Regulator And Its Application
Author(s): Roy J. Becker
Abstract/Introduction:
Over twenty-five years ago, a plug valve was equipped with a pneumatic cylinder and a positioner and used as a monitor regulator. The concept was a new method of gas regulation and was the beginning of a new era. A midwestern utility used these plug valve regulators above grade with relatively good success. They believed, however, that a buried valve regulator would be more desirable than an above ground unit and would greatly reduce the cost of a station. Regulators of this nature were successful and proved to be the key to todays modern high capacity control stations. Many valve configurations can be used to make a regulator, including plug, sliding disc, butterfly and ball valves. Naturally some units will outperform others, prime factors being tight shut-off and low torque.
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Document ID:
396435B4
Production Measurement From Beginning To End
Author(s): Monte K. Hyman
Abstract/Introduction:
The reliability and accuracy of production (wellhead) measurement is critical to a production company from the time the well is drilled until after the hydrocarbons are sold. During the life of the well, measurement information will be evaluated continuously by the producing, measurement, contract, and engineering staffs. The following paper will give you some insight on the inherent procedures and problems that a producing company deals with during the life of a well.
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Document ID:
5BA7C9B2
Transmission Measurement With Rotary And Turbine Meters
Author(s): Gary m. Buchler
Abstract/Introduction:
The purpose of this paper is to discuss the techniques used to acquire a high degree of accuracy when using both rotary and turbine meters in transmission measurement. I will also talk about recommended installation practices for these meters. The major portion of this paper will deal with turbine meters since we have replaced many of our rotary meters with them.
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Document ID:
8B836AFF
Quality Assurmance Sampling For Gas Meters In Service
Author(s): Barbara J. Attenburg
Abstract/Introduction:
Every year, more and more gas distribution companies are considering the use of statistical quality control programs to assure both the customer and the company that individual measurement of gas consumed is accurate, fair and consistent. This paper attempts to briefly outline the major considerations in such a program using the specific case at Elizabethtown Gas Company for explicative purposes. It should be understood that there are many variations in statistical quality control programs from company to company as a result of the differences in the diversity and make-up of the meter populations as well as in State testing and reporting requirements, even though the fundamental objective at the root of the programs is the same. This objective is, of course, to minimize the cost of monitoring and controlling the performance of gas meters in service.
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Document ID:
94055A9B
New Concepts In Recorder Marking Systems For The Gas Industry
Author(s): Robert E. Benner
Abstract/Introduction:
Ink, as a fluid, is virtually worthless . . . ink as a line could be priceless . . . if its in the right place at the right time. For example, a droplet of ink, as a signature on a check, could represent a virtually limitless value . . . even millions of dollars. Well, the ink lines on your gas measurement charts are signatures shovi/ing the value of gas being measured. From the smallest amount . . . several hundred dollars . . . up to major systems transfer or sales points where the value could be millions of dollars. These transactions are measured and recorded daily and, like checks, thousands of charts are sent to the sales office for computation and transfer of funds. Both buyer and seller want to be confident of a fair transaction price and the chart is the check reflecting the volume of gas bought or sold, the line tells the tale. Its the final expression of value combining the measurement methods, instruments, system, procedures, fieldman, home office staff and chart processing all into 12 inches of ink on a piece of paper. Such reliance on these charts makes measurement a very important subject in terms of equipment, people and procedures. Gas is a natural source of energy and, in an era when rising energy costs can grow from 15* to 2.50 per thousand cubic feet . . . the value of each cubic foot is important.
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Document ID:
22D3C9D0
Fundamentals Of Diphragm Meters
Author(s): W. A. Thomas
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.
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Document ID:
8821CA13
Optimizing Your Orifice Meter With Reverse Differential And Stop & Go Orifice Meter Systems
Author(s): Warren Weiant
Abstract/Introduction:
With the concurrent increased value of natural gas and operations cost, the importance of better and more efficient measurement practices has become stringently pronounced. The use of the reverse scale orifice meter accommodates solution for achievement of rigorous standards.
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Document ID:
147D31DD
Stripper Well Measurement - Why, How And What?
Author(s): Paul Lemaster, Keith Campbell, C. E. Stewart
Abstract/Introduction:
We will be discussing the measurement of a stripper well with you. Why? How? What? A stripper well is defined as a well that has delivered 60 MCF per day or less for a specific period of time. 1. Why? The question arises, Why the sudden interest in these low producing wells? The answer Is simply NGPA or the Natural Gas Policy Act of 1978. This act was signed into law on November 9, 1978 to become effective for certain first sales of natural gas delivered on or after December 1, 1978. The ceiling price for gas delivered from a stripper (NGPA Section 108) well was established at 2,224 per MMBTU this price in April, 1982 has risen to 3,314 per MMBTU. Because of NGPA, gas measurement personnel are faced with the necessity of measuring these wells accurately, and in keeping with A.G.A. standards, and, yet, keep the cost of metering as low as possible.
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Document ID:
1A24C3D2
Regulator Selection And Sizing
Author(s): John m. Kruse
Abstract/Introduction:
Prior to discussing the application and selection of a regulation device, lets first define a Pressure Regulator. A 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 regulation device to perform its design function consists of three basic elements. First is the restrictive element which can be a single, double, or multi ported variable opening. Second is the responsive element by which a throttling device is activated. The responsive element usually takes the form of a flexible diaphragm however, it can be a piston or other device which can readily respond to pressure changes. The third element of the Pressure Regulator is the standard. This is the element to which the controlled pressure is referred. It opposes the force exerted by the pressure being controlled. Any change in the balance of these forces results in a movement of the responsive element or diaphragm which in turn affects the movement of the throttling device. The standard also can be of several forms. The type standard utilized will depend on the application and the desired performance. These basically can be spring, pressure or weight type - either direct or by lever. The latter type is basically becoming obsolete.
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Document ID:
F7B42E25
Solar Powered Flow Computers
Author(s): Michael J. Keady, Jr.
Abstract/Introduction:
Traditionally in the flow measurement of natural gas, orifice meter signals have been recorded on-site by means of mechanical circular chart recorders. These charts have been collected weekly or monthly and integrated for volume determination. This procedure has a lenthy lag time between time of actual gas flow and time of reporting. With the advent of spiraling gas prices and penalty clauses for excessive rate deliveries, both customers and suppliers are looking toward quicker and more accurate methods of obtaining flow and total quantity. By the use of field-mounted electronic flow computers, flow information is processed on an instantaneous and continuous basis.
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Document ID:
39DB7DA1
The Ultrasonic Flowmeter - A New Approach To Large Volume Gas Measurement
Author(s): W. D. Munk
Abstract/Introduction:
A wide variety of meters are available for measuring fluid flows in pipelines. Most of these, however, are limited to pipes smaller than 12-inches in diameter. To measure fluid flows in larger diameter pipes, a constriction type differential pressure flowmeter concentric orifice, venturi, etc.), or some type of probe inserted flowmeter (pilot tube, turbine, etc.) is used. High accuracy and wide range are achieved with constriction type meters by using multiple meters in parallel. For example, in the natural gas industry, the multiple orifice meter station is generally considered the standard for large volume high pressure gas measurement. A major drawback to the multiple meter installation is that it is expensive. The cost of an orifice measurement station containing six 12-inch meters in parallel can easily exceed one million dollars. Another drawback is that these stations are, by their nature, permanent installations. As measurement requirements change it is often more practical to build another station where it is needed rather than to move an existing station.
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Document ID:
9846515B
Moisture Analysis In Natural Gas
Author(s): Lee m. Gates
Abstract/Introduction:
This purpose of this discussion is to present an overview of the problems most commonly encountered In the analysis of natural gas for water vapor content, and to provide details on the successful application of the thin film aluminum oxide moisture sensor to this type of measurement.
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Document ID:
21351896
Extend Your Meter Life
Author(s): G. W. Reich
Abstract/Introduction:
To have an accurate Measurement Program is no longer a luxury, but a necessity In this time of tight fiscal conditions. The continuing requirement of explaining to both, the public and the state regulatory agencies the need for rate relief further accentuates this requirement. In search of more economical methods of removing and testing meters in service, both the utilities and state agencies have deviated away from the periodic interval removal plan, based on years in service, to a system based on performance using varied statistical analysis. In simplest terms, the poorer performing meters are removed from service and the best meters remain in service, thus, overall measurement error is reduced.
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Document ID:
75DAD419
Gas Research Institute Programs For Gas Measurement
Author(s): R. A. Day, R. S. Norman
Abstract/Introduction:
As the major funding organization in the U.S. conducting gas distribution research, the Gas Research Institute (GRI) is directing a program in this area worth 3.3 million in 1981 and 4.3 million in 1982. The program is aimed at developing improved, cost-effective construction and maintenance equipment and techniques, new or improved instruments, metering methods, and piping materials. Through these activities, GRI supports the gas industry in providing the consumer with safe, reliable gas service at the lowest possible cost. GRI conducts research in three areas of gas distribution operations 1) construction and maintenance, 2) enhanced utility operations, and 3) piping system design and materials. Research dealing with gas measurement falls under the enhanced utility operations project area.
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Document ID:
5BC5BAEB
Btu Or Dekatherm Measurement Systems
Author(s): Gerald V. Yost
Abstract/Introduction:
In the gas industry the accuracy of gas measurement has always been of the utmost importance. However, as gas supplies decreased and the value of gas increased, more acurate and equitable methods of measurement have been sought. Until recent years, emphasis has been placed on the most accurate measurement of thermal energy. Unfortunalely, thermal energy as such, cannot be measured directly. However, several indirect measurements can be made and the flow of energy calculated. The purpose of this paper is to discuss some of the terminology, methods, instruments and factors in the selection of instruments, which go into the building of energy measurement systems.
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Document ID:
2D6AE078
Fundamentals Of Gas Anaylsis
Author(s): James E. Lincoln
Abstract/Introduction:
The methods of analysis for the various constituents of natural and synthetically-produced fuel gases are discussed. Such constituents include hydrocarbons, inert components, sulfur compounds, odorants and water vapor. Some important factors in obtaining representative gas samples and the types of sample containers required for certain types of analyses are examined. Also discussed are gas blends for analytical instrument calibrations, and the interpretation of the results of a gas analysis.
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Document ID:
3624E902
Energy Measurement Using Gas Chromatography
Author(s): D. L. Aquin
Abstract/Introduction:
Gas chromatography is a physical separation of two or more compounds based on their different distribution between two phases, one of which is stationary and the other a gas. Gas chromatography Is divided into two classes: gassolid chromatography (GSC) which is employed primarily for light cases, and gas-liquid chromatography (GLC) which is more broadly applicable to a much wider range of components. Chromatography had its beginning about 1850 in the separation of dyes by F. F. Runge. In 1906 Tswett described the use of glass columns packed with a suitable adsorbent for separation of colored plant pigments. He applied the term chromatography, colorwriting, to this process. The first apparatus was described by Martin and James in 1952, but the real potential of the technique could not begin to be realized until the publication by Ray of the first chromatogram in 1954. The detector he employed was thermal conductivity - still in widespread use today. In about 1955 the first commercial instruments became available.
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Document ID:
9466B2E1
Specific Gravity Instruments
Author(s): Douglas F. Porter
Abstract/Introduction:
The specific weight of gas is the number of units of weight in a unit volume, where as specific gravity isthe ratio of weight of a definite volume of gas to the weight of an equal volume of dry air, free from all carbon dioxide and measured at the same temperature and pressure. Theoretically, specific gravity of a gas may be defined as the ratio of molecular weight of a gas, or a mixture of gases, to molecular weight of dry air. Specific weight is a measurement of the relative weights of gases and va/ies according to the conditions under which it is determined, where as specific gravity compares all gases to dry air as the standard. From a comparison of the above definitions, it is seen that specific gravity is the ratio of the specific weight of a gas to the specific weight of dry air, both being at the same conditions of temperature and pressure. It should be noted that specific gravity is temperature and pressure dependent.
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Document ID:
7EE4BB89