Measurement Library

Southwestern Gas Measurement Short Course (Now called ISHM) Publications (1938)

International School of Hydrocarbon Measurement

Recording And Controlling Instruments Applicable To Gas Measurement And Regulation
Author(s): L, G. Marsh
Abstract/Introduction:
TN no industry is greater attention being paid to the factors of measurement and regulation than in the Natural Gas Industry. Efficiency and economy in production, transportation, and distribution are measured in great part by accuracy in measurement and smoothness and regularity in delivery. Measurement is the keynote in production and sale of the commodity. Regulation is the factor which aids in accurate measurement and assures delivery of the product in the quantities and under the conditions required. Measurement and regulation are based fundamentally on temperature and pressure. Accuracy in the determination and maintenance of these factors is made possible by the proper application and design of instruments which have been developed for these needs. It is not only important that tire gas engineer or meter man recognize the necessity for various applications but it is of equal importance that he make the proper selection of instruments for tlie problem at hand.
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Document ID: B1F3EE40

The Foxboro Orifice Meter
Author(s): H. K. Spink
Abstract/Introduction:
H E COMPLETE orifice meter, besides the Recorder whloh is the most evident part of the mechanism, is composed of an orifice plate which serves as a restriction and causes the drop in pressure which registers on the Recorder, a flange union which holds the orifice plate, a set of pressure taps, and the section of line leading to and from the orifice. These latter accessories are just as important and are much more likely to get out of order than the Recorder itself. In order to obtain an accurate measurement of flow, the following conditions must be fulfilled: An accurate differential pressure, accurately related to Che rate of flow, must be created this differential pressure must be conveyed to the Recorder the Recorder must make an accurate record of this differential an accurate static pressure must be conveyed :o the Recorder the Recordermust accurately register ihis static pressure accurate readings of gravity and flowing temperature must be used in computing an accurate coefficient and an accurate method of reading the charts must be applied in connection with :his coefficient.
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Document ID: C4A43116

The Cutler-Hammer Recording Calorimeter
Author(s): G. m. Arnold
Abstract/Introduction:
TN T H E production of gas for domestic and industrial use, its heating value should he kept as uniform as possible. Whether manufactured from coal in the conventional gas plant or produced from wells as natural gas, the problem Is the same. In general, gas for domestic use is distributed under franchise from the city which stipulates its B, T. U. content and the rate which can be charged for it. Regulations also set up certain limits of B. T. U. variation which cannot be exceeded without incurring penalties. The utility company exerts every effort to render good service to its customers by maintaining such gas heating value and pressure as will result in best appliance performance. It is also desirable to hold the heating value as close as possible to the B. T. U. set by franchise for anything in excess represents a loss in revenue. In the sale of gas for industrial use the same situation holds. Industrial burners are usually more critically adjusted and are more sensitive to B. T. U. variation. Many contracts for sale of gas for industrial use are now including B. T. U. clauses and also provide premiums for imiform quality.
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Document ID: D6F53DC1

Well Testing
Author(s): L. T. Potter
Abstract/Introduction:
TT IS obvious to anyone connected with any phase of the gas business that the sources of gas supply occupy a place of great relative importance in the operation of a natural gas transmission system. A natural gas transmission sjStem cannot operate without adequate sources of supply and, even if the sources of supply are adeciuate, the most efficient operation of a system cannot be attained unless the operators of the system have available, to blend with other operating information, complete and accurate data with reference to the characteristics and capacity of the sources of gas supply available.
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Document ID: D3561C26

The Flat Plate Orifice Meter
Author(s): Allen D. Mclean
Abstract/Introduction:
Mr. Eatill: The first speaker is a man we have all known for some time. He has been coming to the Meter School for a long time. We are always glad to hear from him. Mr. A. D. McLean, Pittsburgh Equitable Meter Company. I like to point out what these mens hobbies are. With your permission, Mr. McLean, 111 tell what your hobby is. He composes music when he isnt figuring out all these engineering problems. I want to introduce Mr. A. D. McLean. Mr. McLean: My friends . . . I can see you are all utility men, anyway. My talk this morning is on the orifice meter. Its a very simple meter, really. Its just a hole you push gas through, and a sort of glorified recording mechanism. However, it is much simpler, actually, than the theory behind the orifice meter. The magnetics involved and the physics involved are very complicated. It really is necessary to go pretty deeply into some of it. I am going to impose some on you boys. I am going to ask you to wade through it.
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Document ID: 53D5574E

Fundamental Principles Of Measurement By Displacement Gas Meters
Author(s): A. F. Benson
Abstract/Introduction:
npHE RECIPROCATING steam engine producing continuous rotation of a fly wheel was invented in 1781 by J. Murray Watts. The cycle or sequence of events, namely, the position of the valve relative to its seat, and the position of the piston relative to the crank as used in that engine are used in the modern steam engine. This same cycle is used in domestic and large capacity diaphragm gas meters. The steam engine mentioned above consists of a cylinder, piston, crank and valve mechanism. These parts are diagrammatically shown in the following slides. The gas meter consists of the same parts, but the forms of some are slightly changed. For example, the following slides, Fig. 1 to 4 inclusive, show a diaphragm replacing the piston of a steam engine. Now, for ease of construction and longer life, the diaphragm of a gas meter is normally located and of the shape shown in the slide, Pig. 1. We can see from this slide, then, that there are four measuring compartments, two being the portions inclosed by the diaphragm and the diaphragm disc, called the diaphragm compartment, FD and BD the other is the compartment inclosed by the case and outside of the diaphragm and its discs, called the case compartments, PC and BC.
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Document ID: 0E976173

Rotary Displacement Gas Meters
Author(s): F. F. Borgaruds
Abstract/Introduction:
rotary as turning around as a wheel on an axis or having parts that turn around and displacement as replacement of one thing by another. This is fundamentally what yon find in the rotary displacement type meter where two rotating parts called impellers replace a definite volume of gas every time they turn around. This type differs from the commonly known displacement type of meter in that the gas pockets, instead of being determined by the capacity of diaphragms or leathers, are determined by machined metal surfaces whose dimensions cannot be changed. These impellers, whose machined shape determines the amount of gas displaced per revolution, are made of cast iron and resemble the Figure Eight in shape. They are mounted on steel shafts supported on anti-friction bearings, one at each end of each shaft and rotate in a horizontal plane in opposite directions at speeds proportional to the volume of gas passing through the meter. The impellers do not touch each other or the cylindrical casing in which they revolve, this being accomplished by accurate machining of the different parts and correct spacing of the impellers with relation to each other by means of a pair of timmg gears located at each end of the shafts supporting the impellers. This whole assembly is mounted on a substantial bedplate with proper pipe connections and is normally set on a substantial concrete or masonry foundation. Pigm-e 1 shows the various parts referred to and their method of assembly.
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Document ID: 991A0351

Fulton Regulators
Author(s): Thos. H. Thorn
Abstract/Introduction:
T H E general session the theory and fundamentals of regulators have been thoroughly discussed. Therefore, these will be reviewed only in so far as they may concern our classroom work on Pulton Regulators. Our purpose in meeting is to endeavor to aid you in the solution of any problems involving regulators of om- manufacture. Further, many of you may have questions concerning regulator repairs and shop practice. Mr. Shipley is well qualified to assist us in these as well as field servicing of regulators. Past experience in conducting these classes has proven that the maximum benefit is obtained through informal discussion. But first, by means of the illustrations, let me briefly outline the duties of some of our standard regulators. We will then devote the balance of the period to an open meeting.
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Document ID: 497AC76E

Problems Of Wet Gas Measurement And Regulation
Author(s): E. J. Turner
Abstract/Introduction:
rpHE PROBLEMS of Wet Gas Measui-ement and Reguation are many and varied and are increasing in number and perplexity as production is being obtained at greater depth. Since Wet Gas carrying gasoline or distillate either in vapox-ous form or in liquid form carried in suspension, such as retrograde condensate, is being produced fiom wells in excess of 7,000 deep and at working pressures in excess of 3,000 lbs., it can well be said that the measm-ement and regulation of Wet Gas has all of the problems of dry gas measurement and regulation in addition to the problems peculiar to itself. The problems confronting a meter man in a flush field are worthy of much consideration. The production from practically all flush fields is now prorated and in order to obtain their production most economically, and to prevent the depositation of paraffin, lessees generally produce their allowable oil In a relatively short time. The days production is sometimes attained in less than twenty minutes flowing time and in isolated cases where the actual production is far behind the allowable as much as a months production has been produced in a days time. Wells in new fields usually flow naturally and at a relative constant rate, later in tne productive life they flow by heads, and still later by the injection of gas either constantly or intermittently for production on gas lift,
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Document ID: 020D8069

Problems Of Wet Gas Measurement
Author(s): W. F. Delametter
Abstract/Introduction:
rpHE problems of wet gas measurement afford a great many interesting, though troublesome, proDlems. which, while differing considerably in individual fields, are on the whole very similar when all gas fields are considered. The problems submitted here probably have been encountered at one time or another by everyone present. The following list will give an idea of some of the things to be taken into account when measuring wet gas
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Document ID: AB20433F

Low Pressure Or Appliance Type Regulators
Author(s): R. C. Hughes
Abstract/Introduction:
OW PRESSURE Regulators are made in two types considering adjustment of delivery pressure, namely, Spring and Dead Weight. They are also manufactured in single and double valve, iSee Drawings R-400-E and R-400-AE.) Figure 1. The double valve is for all purposes a balanced regulator but there is generally a difference of about 1/8 in the diameters of the two valves. The single valve construction is of two types-balanced and unbalanced, the balance type making use of a balancing diaphragm. It is only natural that the balance type of regulator will give greater accuracy in control of delivery pressure than the unbalanced regulator. The small type of regulators such as are used on refrigerator installations, are all single valve construction and of unbalanced type, but due to the practically constant and small flow, they give very accurate results.
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Document ID: 1E12F2CA

Functions Of Field Metermen
Author(s): C. L. Quast
Abstract/Introduction:
The function of a meterman are governed by his ability to understand and apply the theory and principles of gas measurement, as well as being mechanically able to diagnose and correct faulty measurement with the ease and skill of a technician. Ordinarily we think of a meterman as one who repairs meters, but I prefer to think of metermen as gas measurement engineers. The word meterman takes on as many meaning as there are companies employing men in that classification.
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Document ID: 3C88D044

Care And Operation Op Orifice Meters
Author(s): Pat H. Miller
Abstract/Introduction:
Each of our companies is interested in orifice meter measurement. The management looks to us for accuracy. It is then our duty to familiarize ourselves with each setting under our supervision to the extent that all features of construction, installation, condition of equipment and manner of operation are judged to meet those of accepted standards. When first approaching an orifice meter setting, an alert meter man will not fall to make general observation of its basic construction and installation features and the general condition of the equipment. He will then proceed with a separate careful inspection or test of each essential part. His written report to the Gas Measurement Office will cover the existing facts, physical measurements and conditions so completely that the efficiency of the setting can be definitely established.
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Document ID: 5BD09973

Methods For The Determination Of The Hydrogen Sulfide Content Of Natural Gas
Author(s): P. V. L. Patten
Abstract/Introduction:
The determination of the hydrogen sulfide content of natural gas I based on two properties of hydrogen sulfide. There are 1 the ability of hydrogen sulfide to react metathetically with salts or hydroxides of metallic ions to form metallic sulfide 2 the ability of hydrogen sulfide to be oxidized to free sulphur with the accompanying reduction of another compound. These reactions are numerous, and have given rise to a great number of methods for determining hydrogen sulfide. They probably may be best classified under the following heading: Colorimetric determinations and Absorption and titration methods.
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Document ID: 0DA50DC9

Remote Measuring And Control Instruments In The Natural Gas Industry
Author(s): Perry A, Borden
Abstract/Introduction:
rpHE BASIC idea of a telemetering installation is to reproduce, at a convenient location, a measurement made at a remote point, and to express this measurement as an indication, a graphic record, or often, in cases of flow measurement, as an integration of the total volume passing the point of measurement. To these basic functions may be added those of totalizing measurements made at a number of more or less separated points, and of providing a control of pressure or flow at one location in order to maintain desired conditions at another point in a system. The remote measurement and control of industrial quantities originated in the electrical power field about 1912, and was early followed by instruments and devices for providing distant records of non-electrical magnitudes, such as liquid, level and flow. In the past fifteen years the art has been greatly broadened, and is now adapted not only to providing an indication or graphic record of a quantity measuied at a remote location, but also to a number of other purposes, as suggested above.
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Document ID: 698992DC

Obtaining Performance Prom Regulators
Author(s): L. S. Stabler
Abstract/Introduction:
Successful regulator operation depends not only on physical characteristics of the various parts comprising the regulator but also on certain external factors that influence its reactions and the resulting performance. As large a downstream storage volume as possible is desirable in that it permits the regulator to overrun without sever fluctuation in the controlled pressure. Under conditions of limited downstream capacity and rapid varying loads, appreciable changes in controlled pressure are possible which are conductive to a pulsating regulator. To be considered with downstream pressure tap. If it is too near the discharge side of the regulator, varying flows may produce dynamic effects creating a false pressure that is transmitted to the diaphragm on the other hand, if the tap is located too far from the regulator the pressure drop through the pope and intervening fittings, varying approximately as the square of the flow, may result in a cycling controlled condition. Closely related to the location of the pressure tap is the debatable question of its size which it is believed tends to be larger than necessary in a great many cases. Further mention of this fact will be made later in the paper.
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Document ID: AE93F923

The Ac-Me Recording Gravitometer
Author(s): H. F. Goodenough
Abstract/Introduction:
rpHE EFFECT of the specific gravity on the measurement of the gas through an orifice meter is taken into account when calculating the coefficient. To determine the importance of the gravity in this connection, consider the coiTection factors for different gravities. For example, when using a gravity base of .60, the correction factor for a specific gravity of .59 is 1.0084 and the correction factor for a specific gravity of .61 Is .9918. From these two correction factors it is indicated that a difference of .01 in the specific gravity of the gas will make a difference in delivery of almost one per cent. When the specific gravity of a gas remains reasonably constant over a period of time, the specific gravity gas balance is the proper instrument to use in determining the specific gravity of the gas for correction purposes. Periodic tests are made at intervals suitable to the conditions. On the other hand, when it is known that the specific gravity of the gas does not remain constant during the period, a continuous record of the specific gravity is necessary for obtaining the correct flow. The record of the specific gravity for any period is used to correct the orifice meter measurement for the same period. When it is realized how the specific gravity changes under some conditions, it becomes apparent that the gravity record is of importance to the accurate measurement of gas by an orifice meter. Figure 1 is a reproduction of a chart from an Ac-Me Kecordmg Gravitometer which illustrates variations in specific gravity that are sometimes encountered. In this particular instance, the installation was made in a city gate measuring station. The cause for the variation in specific gravity was the fact that the gas being measured was made up of natural gas from two separate sources.
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Document ID: 71855345

Major Gas Fields And Reserves Of Kansas
Author(s): J. H. Page
Abstract/Introduction:
Mr. EstUl: Our next paper is Major Gas Fields and Reserves of Kansas by Mr. J. H. Page of the Kansas Corporation Commission. Mr. Page. Mr. Page: Before I take up the subject of gas reserves of Kansas, I wish to make a brief explanation of what we, of the Conservation Division of the State Corporation Commission of Kansas, are attempting to accomplish in the way of gas conservation. For one thing, we are endeavoring to prevent unnecessary waste which so often occurs where there is an over-supply of gas, and it is being produced in conjunction with oil from combination oil and gas wells. We have several large pools in KansaiS where such conditions exist and the State Corporation Commission lias held hearings, after field investigations were conducted, and has issued Orders limiting the amount of gas permitted to be produced per barrel of oU. In other pools which are in process of development we are attempting to secure the cooperation of the operators in casing off any large amount of gas encountered above the oil producing formation and where there is no market for this gas.
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Document ID: 9E12225A

The Behavior Of Gases Under Abnormal Conditions
Author(s): R. L. Huntington
Abstract/Introduction:
T H E measurement of gases under high pressure and atmospheric temperatures, the problems of condensation and freezing are the cause of much trouble and expense to the oil and gas producers, the natural gasoline nianufacturer, and the gas distributor. It is essential for those who are concerned with such problems that they know the physical and chemical relationships existing between gases and the objects (liquids and solids) with which they come into contact. Before considering these relationships, It might be well to consider the respective properties of gases, liquids, and solids in general.
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Document ID: 2C47888A

Elementary Gas Laws
Author(s): E. P. Dawson
Abstract/Introduction:
In all gas calculations where the gas laws are applied, absolute temperature must be used. Absolute temperature is a temperature measurement from a point called absolute zero temperature, In Fahrenheit units the absolute zero temperature is located 492 degrees below the freezing point or 460 degrees below the zero point of the Fahrenheit scale. In order to change a Fahrenheit temperature reading to the absolute Fahrenheit scale, one has but to add 460 to the Fahrenheit reading,
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Document ID: 6A695C4B

Determination Of Line Losses High Pressure Lines
Author(s): W. R. Beardsley
Abstract/Introduction:
Every gas company operating high pressure lines keeps some account of leakage. Some companies keep continuous records of leakage of each line or section of line. Other companies keep records only of the difference between purchases and sales or production and sales. This difference is known as lost and unaccounted for gas. There is a difference between lost and unaccounted for gas and actual leakage. The former includes, besides leakage, errors in measurement and unmeasured gas used in company operations the latter includes only that part of the unaccounted for gas which actually leaks from the pipe line and which is a dead loss to the company.
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Document ID: 35DFFF8F

Pilot Operated Regulators
Author(s): Norris Plank, J. F. Swab
Abstract/Introduction:
The demands of closer regulation in both the natural gas and natural gasoline industries have focus considerably attention on the pilot controlled regulator, and suitable pilots are now available for every step of regulation from the well head to the final utilization of the gas.
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Document ID: 56BD6172

Pilot Regulators Design And Application For The Gas Industry
Author(s): L. J. Griffey
Abstract/Introduction:
Pressure regulators have always been used in the gas industry, but most of the regulators placed in service prior to recent years have been of the direct operated, weight or spring loaded type. These regulators were not always satisfactory due to the variation in controlled pressure necessary because of irregular flows.
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Document ID: B7357461

Lost And Unaccounted For Gas
Author(s): A. P. Cox
Abstract/Introduction:
jiHE DIFFERENCE between the amount of gas purchased at the city gate meter or meters and the amount of gas sold as reflected by a totalization of the consumers meters is commonly known as Unaccounted For Gas. This figure of Unaccounted For Gas is made up of two parts, Actual Leakage and Apparent Leakage. Apparent leakage is caused by metering Inaccuracies sometimes brought about by the effect of variables which are normally considered negligible, and sometimes brought about by the mechanical limitations of the installed metering equipment. These apparent leakage figures, if given serious study in the office, can in many cases be greatly reduced without large monetary expenditures. Actual leakage presents a much more seiious problem not only due to the cost of the gas which is being lost but also due to the hazard of a possible explosion produced by ignition of a combustible mixture which is a result of the leak,
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Document ID: B96DA6C8

Helpful Hints On The Installation And Maintenance Of Regulators
Author(s): Charles D. Peterson
Abstract/Introduction:
rpHE PURPOSE of this paper is to present to the class some suggestions regarding the proper methods to be used, both in the installation and servicing of pressure regulators or pressure controllers. It has been observed that, in the field, control equipment many times is abused, not intentionally on the part of the operators but because they are not aware of the proper methods of handling these items and doing sueli work. There will be discussed here under separate headings a number of non-related subjects which are fundamental and applicable to practically all makes of regulators and controllers.
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Document ID: EE2A2DA6

The Effect Of Barometric Pressure On Gas Measurement
Author(s): Sylvan Cromer
Abstract/Introduction:
T3EPOBE ENTERING a discussion of the effect of barometric pressure on gas measm-ement, it wUl be well to briefly review some of the fundamentals dealing with the problem.
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Document ID: DAAF1F04

Various Methods And Apparatus For The Determination Of The Specific Gravity Of Gas
Author(s): H L, Oder
Abstract/Introduction:
Specific gravity is, in general, the ratio of the density of a substance to the density of some other substance arbitrarily chosen as a standard, each being taken under certain standard conditions.
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Document ID: 972667BB

The Slide Rule
Author(s): E. E. Ambrosius
Abstract/Introduction:
The calculations which the average engineer is required to make in ordinary work are numerous. He could hardly be expected to make them if he did not have the necessary calculating device. Inasmuch as he cannot always carry with him a large bulky calculator he must resort largely to the use of a slide rule. The slide rule has sufficient accuracy for most engineering calculations and as a result is furnishes a means of performing rapid and reasonably accurate calculations. Little time is required to become familiar with its operations, and with little practice reliable results can be obtained.
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Document ID: 173E870A

Fundamentals Of Automatic Pressure Controllers
Author(s): K. R. D. Wolfe
Abstract/Introduction:
Without further ado, I think we will get into this paper, because we are about a half or three quarters of an hour late. I want to talk to you about the fundamental principles of regulators, gas pressure regulators in particular. Many times I have asked what is the background of the history of the automatic pressure controller. It seems to be a rather remote and hard to define history. I am more or less inclined to believe that automatic controller have been developed more or less along the of the story of little Topsy.
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Document ID: B6DD997F

The Emco-Mcgaughy Integrator
Author(s): J. Li. Cottrell
Abstract/Introduction:
The gas industry has developed, from the days when wooden pipelines were used, to a large industry with high pressure gas lines extending to practically all sections of out country. With this development there had been a constant study by the industry and various manufacturers to improve methods of producing, transporting, measuring and distributing gas to the consumers.
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Document ID: 8E15E650

Calculation Op Orifice And Displacement Meter Charts
Author(s): m. W. Patterson
Abstract/Introduction:
THE measurement of gas we are confronted with problems much different than in measuring oil or other commodities. Oil may be stored for future use and measured when convenient, but gas being of a different nature must be measured at the time it is produced or consumed, by meters especially adaptable for this use. The meters used by the industry at this time are the Orifice and the Positive displacement meter, with or without a recording pressure gauge. The meters record conditions on chart records at the time the gas passes, which recordings become the basis of calculating volumes. As this record cannot be dupUcated after the gas has passed the point of measmement, It is imperative that an accurate recording be obtained on the chart. The care and operation of meters is another subject and is covered more fully in another class at the school but being so closely connected with the calculation of tlie charts, a few remarks concerning the meters are not out of place in this discussion. Unless the meters are function Lng properly and are recording correct conditions, it would not matter how carefully a chart is read, an incorrect result would still be obtained. A good meter attendant or chart changer is an essential factor in obtaining correct gas measurement. The two methods of measuring gas and the calculating of the different type charts should be studied as individual subjects.
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Document ID: C890296B

Field Testing Of Large Capacity Displacement Meters
Author(s): Charles Mitchell
Abstract/Introduction:
AEGE CAPACITY displacement meters occupy a minority percent of the total number of meters on a transmission system, also they pass a relatively small percent of the total volume. Nevertheless, it is a very important duty of each meter inspector to keep his positive meters accurate. Due to their siae and oftentimes remoteness from the shop it is impractical to bring the meters in for a test, therefore, he must test them on location. Some companies require a test every three months, some every sis months, depending on policy, etc. There are several methods of testing, all of which will give similar results if properly used. The method selected largely depends on company practice as well as the case. I will attempt to discuss these methods and their adaptions.
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Document ID: E83E8702

Operation Of The Gas Calorimeter
Author(s): Frank H. Dotterweich
Abstract/Introduction:
A number of natural gas and oil gas contract have been written specifying rates per thousand cubic feet according to a sliding scale based upon the average BTU content or in some cases specifying that this content should be determined according to the methods proposed by the United States Bureau of Standards.
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Document ID: ED27FBDC

The Modern Proving Room
Author(s): P. L. Pairchild
Abstract/Introduction:
The international Bureau of Weights and Measure near Paris have preserved in their vaults two lines on a metal bar, the distance which is known as a metre. A very accurate copy of this bar is deposited in the United States Bureau of Standards in Washington DC and since the length of this material changes slightly at the temperature of melting ice. Here we have a legal standard which can be referred to at any time should there be the slightly doubt as to the accuracy of existing standards of this linear unit of measure.
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Document ID: D3ADE8C3


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