Charts, Pens, And Ink
Author(s): David Kraus
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 representavirtually limitless value.. .even millions of dollars. Well, the ink lines on your gas measurement charts are signatures showing 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 thefinal 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 1 SfC to 2,50 per thousand cubic feet. . . the value of each cubic foot is important.
Go to Download Page
Email Reference
Document ID:
3CBB6DBE
An Improved Meter Calibration Technique: The Laminar Flow Element Approach
Author(s): Mark S. Kacik
Abstract/Introduction:
Commercial and domestic gas usage is measured primarily by rotary, turbine and diaphragm type meters. The responsibility to provide accurate meters to assure correct billing is one that utility companies have always recognized and responded to. Of course, in recent years the emphasis on accurate measurements has increased as users became concerned with the impact of the spiraling cost of gas. The billing meter accuracy is often questioned in billing disputes. The ability of a utility company to prove accuracy of billing meters is essential to billing credibility. Specific calibration capabilities required of utility companies are most often outlined by PUC Commissions. This paper reviews common approaches to calibration of billing meters. An alternative approach to these methods is introduced utilizing Laminar Flow Elements (LFE) type primary elements. It will be shown that the LFE provides benefits such as ease of use, accuracy, cost effectiveness and portability.
Go to Download Page
Email Reference
Document ID:
71583CF2
Selectioin And Sizing Of Regulators
Author(s): Eugene J. Escolas
Abstract/Introduction:
Insight into selection and sizing regulators for use at City Gate, District, Large Volume Sales and Local Production Delivery Stations. Basically 2 size and larger. Brief overview of the three basic pressure control systems available for pressure regulation, Brief overview of some operating considerations in selecting and sizing regulators for specific applications.
Go to Download Page
Email Reference
Document ID:
63CFA4D5
Automated On-Stream Calibration Of A Turbine Meter Station
Author(s): Marsha C. Yon
Abstract/Introduction:
The ever increasing use of gas turbine meters has created many problems in establishing suitable methods for field testing. The requirements for field testing are predetermined by the need, through contract or otherwise, to maintain and demonstrate accuracy in measurement. The topic of this paper is a fully automated system which can accomplish on-stream gas turbine meter proving under field conditions.
Go to Download Page
Email Reference
Document ID:
64AB9DA7
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 analyzed. 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).
Go to Download Page
Email Reference
Document ID:
59CF8062
Low Power Field Flow Computers Part 2
Author(s): James H. Griffeth
Abstract/Introduction:
Natural Gas - the commodity that we have all come to know, was not considered a primary source of energy in the early 1900s, Manufactured gas was used predominantly in the cities for operation of street lamps and to some extent, heating and other processes. Although natural gas was considered to be a more efficient fuel, the problem of transporting this fuel from the production field to the consumer was a monumental task. Oil from the production fields could be easily transported via truck or rail tankers to processing plants but an efficient means of transporting natural gas was another story. In the process of searching for crude oil, the natural gas discovered was in many cases simply vented to atmosphere. It was not until gas transmission networks were completed that natural gas became a primary fuel for the end user, and therefore measurement of the fuel became important.
Go to Download Page
Email Reference
Document ID:
A9C0D7BC
Specific Gravity Instruments - Operation And Maintenance Ugc Gravitometer
Author(s): E. J. Dupuis
Abstract/Introduction:
The specific weight of gas is the number of units of weight in a unit volume, whereas specific gravity is the 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 meaurement of the relative weights of gases and varies according to the conditions under which it is determined, whereas specific gravity compares all gases to dry air as the standard. From a companson 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.
Go to Download Page
Email Reference
Document ID:
D45F0B74
Instrumentation For Determination Of Water Vapor
Author(s): Steve Dunkle
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 H2O per MMCF in our main lines and sales points. Therefore, our moisture monitoring iscritical and requires more attention.
Go to Download Page
Email Reference
Document ID:
18A9573D
Fundamentals Of Diaphragm Type Positive Displacement Meters
Author(s): John Esola
Abstract/Introduction:
The Positive Displacement Meter principle is applied on both diaphragm type and rotary type meters. Although the operational principle is different, the fact remains that both types measure by means of sealing off a known quantity of gas, and subsequently releasing it. The bulk of the meters in use today are of the positive displacement type. Over 40 million gas meters are employed in measuring gas volumes by positive displacement in the U.S. Of this total, the large majority are used to measure gas volumes consumed by domestic residential customers. Other measurement principles are applied in the case of the Turbo-Meter, Orifice Meter or Swirl Meter.
Go to Download Page
Email Reference
Document ID:
C4E5157D
Fundamentals Of Gas Chromatography
Author(s): Arthur F. Haas
Abstract/Introduction:
Chromatography is a method for the separation of all components in mixture, such as natural gas, both quantitatively and qualitatively. Afterthis separation is performed it is possible through computation to generate data important to volumetric measurement and value assessment. The data most normally generated from compositional analysis data is B.T.U. Specific gravity liquid equivalents, etc.
Go to Download Page
Email Reference
Document ID:
6DDB1120
Fundamentals Of Instrumentation
Author(s): Peter J. Hanowich
Abstract/Introduction:
Turbine meters, like all other metering devices, measure natural gas at line conditions. Gas volumes vary with changes in temperature and pressure following the well known Boyles and Charles Laws. Base conditions provide a common reference for measuring gas at an inlet pressure of 4 oz, and a temperature of 60 F. Any variance in these parameters requires a calculation to correct the gas line volume to base volume. A number of ways have been evolved by the industry to obtain this base volume.
Go to Download Page
Email Reference
Document ID:
E100AEE4
Turbine Meter Update
Author(s): Joseph L. Pond
Abstract/Introduction:
A capital investment in measurement and control equipment represents a long-term investment. Installations made today can certainly be expected to be in place in the year 2000 and beyond. It is therefore relevant to consider the commodity prices projected for the future. Although a number of different pricing projections are available, the following was recently published by an American Gas Association task group
Go to Download Page
Email Reference
Document ID:
2DE54B4F
Brine Disposal For Gas
Author(s): Ronald R. Walsmith
Abstract/Introduction:
In discussing brine disposal for either gas storage or production there are four basic considerations which must be made, These concerns are (1) type of brine, (2) legal restrictions, (3) purpose of brine disposal, and (4) the type of system to be used. Although most produced brines are predominantly sodium chlonde (NaCI) other ordinary salts such as potassium chloride (KCI) and calcium chloride (CaClg) are sometimes found. Semi-occasionally a company finds itself with the good fortune of having a produced brine of mostly CaC!2 which has a slight commercial value. If that is the case disposal becomes no problem, but since that is not the case most of the time brine disposal is a problem today.
Go to Download Page
Email Reference
Document ID:
F1193B92
Principles Of Moisture Analysis
Author(s): E. J. Rosa
Abstract/Introduction:
The term moisture refers to the water content of any material - solid, liquid or gas. However, its customary to use the word moisture for the water content of solids or liquids, reserving the term humidity for the water content of gases. This discussion of the principles of moisture analysis will cover basic concepts, definitions and units followed by descriptions of the commonly used instrumental methods including their strengths and weaknesses. After considering some moisture calibration techniques, the discussion will conclude with a series of review questions.
Go to Download Page
Email Reference
Document ID:
8B2425F2
Field Testing With A Transfer Prover
Author(s): Josepli G. Fabrizi
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 Power 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.
Go to Download Page
Email Reference
Document ID:
B94BA7A6
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, industhal, 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.
Go to Download Page
Email Reference
Document ID:
8C43A4AD
Calculation Of Gas Lost Due To Breaks, Ruptures, Or Third Party Damage
Author(s): Michael D. Frederick
Abstract/Introduction:
The increasing value of natural gas in recent years has placed greater emphasis on the use of a good method for the calculation of gas lost due to various instances. This paper will deal with the basic methods used by Consolidated Gas Transmission Corporation for the calculation of gas lost due to line breaks or ruptures. There are several equations that may be used for this calculation. The basic equations and the conditions that indicate their use are outlined below.
Go to Download Page
Email Reference
Document ID:
80D5C70C
Relief Valves
Author(s): Lawrence P. Sipsky
Abstract/Introduction:
The relief valve has been used by the gas industry as a way of providing overpressure protection in transmission, distribution systems, and for individual customer installations. Acting as a self-contained, independent device, a relief valve works by limiting pressure downstream of a gas regulator to a specific, tolerable set point. This of course, should only happen in the event of failure of the regulator to function mechanically, or due to foreign matter in the supply not allowing positive shut off to occur. This would lead to an increase in outlet pressure, possibly to a dangerous level. The relief valve would open, thereby allowing excess gas to be discharged into the atmosphere, thus maintaining safe pressure in the system.
Go to Download Page
Email Reference
Document ID:
BE0FD581
Theoretical And Practical Aspects Of Meter Sampling
Author(s): Sharon Clauer Siggins
Abstract/Introduction:
In todays economy utilities need to reduce their costs in order to remain competitive with alternate energy sources. One way to contribute to this reduction is to employ a more economical program for the removal and testing of meters in service. Many methods are available to accomplish this end, but they all have one factor in common. All concentrate on removing the poorly performing meters and leaving the more accurate ones in service. The purpose of this paper is to review the methods of monitoring and controlling meter performance through statistical sampling. We will show this to be a better method than just replacing meters based on length of service. Implementation of the methods that will be discussed should provide reduced change-out costs while maintaining high measurement accuracy. The purpose is thereby in line with the American National Standard B109.1 for In-Service Performance Programs of Gas Displacement Meters. The objective section of this Standard is re-printed below for reference.
Go to Download Page
Email Reference
Document ID:
07EE0F79
Design And Operation Of Rotary And Turbine Meter Installations
Author(s): John J. Janicki
Abstract/Introduction:
The first rotary meters were developed in the early 1920s and have been used as a gas measuring device for many years. A rotary meter is classified as a positive displacement meter since it measures volume by alternately filling and emptying measuring chambers of constant volume in a repeating process. There are two basic rotary design types in use today, the first being the original impeller type as shown in Figure 1, which consists of two figure 8 contour impellers rotating in opposite directions, providing four separate gas volumes per revolution. The second is the rotating vane meter as shown in Figures 2 and 3, Depending on the manufacturers design, these meters consist of a number of equally spaced vanes rotating around a stationary member passing through a rotating gate which allows the vanes to pass back from the inlet to the outlet side of the meter and preventing the gas from bypassing the measuring chambers. The total displacement of these meters equals the amount of gas trapped between the vanes and released downstream during one revolution. Rotary meters are available in digital counter registrations and instrument drive output shafts.
Go to Download Page
Email Reference
Document ID:
4C00C3B7
Regulator Sensitivity With Stability Or Instability - Cause And Correction??
Author(s): J. m. Kruse
Abstract/Introduction:
Prior to discussing regulator sensitivity with stability or instability, 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 regulator device to perform its design function consists of three basic elements. The first is the restrictive element which can be a single, double, or multi ported variable opening. The second is the responsive element by which a throttling device is activated and controlled. 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. The standard element governs the control pressure setting and 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. The standard can basically be a spnng, pressure or weight type - either direct or by lever. The latter type is basically becoming obsolete.
Go to Download Page
Email Reference
Document ID:
1C29B470
Electronic Volume Correction
Author(s): Ron Hairston
Abstract/Introduction:
A question often asked in the gas measurement industry is In this age of inexpensive calculators, personal computers, and space-age technology, why is it that we see so many mechanical volume correctors and mechanical chart recorders still being utilized?. The most important reasons are cost and lack of a cost effective power source. It is certainly true that we have had the technology to produce accurate and reliable electronic volume correctors since the mid-1970s. But the problem has been getting performance at a reasonable price. Electronic volume correctors are subjected to severe environmental conditions that cheap consumer electronics cannot survive. You wouldnt dream of trying to operate your personal computer outdoors in the direct summer sun in Phoenix, Arizona, nor would you expect your LCD liquid crystal display) calculator to operate after spending a winter night outdoors in northern Minnesota. For electronic volume correctors to be accepted, they must not only be able to withstand all the outdoor elements, they must also maintain accuracy under all conditions of outdoor exposure.
Go to Download Page
Email Reference
Document ID:
B8284715
Industrial Metering With Rotary And Turbine Meters
Author(s): John F. Hunt
Abstract/Introduction:
Before the development and acceptance into the gas industry of rotary and turbine meters, large volume measurement was generally accomplished with orifice or banks of paralleled diaphragm meters. The latter designs, although still useful in certain installations, can be costly, space consuming and require additional maintenance and operational manhours. This discussion covers the details and logistics of metering large industrial customers for billing purposes with rotary and turbine type meters. It is from a gas distribution companys point of view, with main pressures up to 100 PSIG and customer loads up to 400 MCFH range. City gate, transmission or production applications may not necessarily follow the same economic and technical criteria.
Go to Download Page
Email Reference
Document ID:
A0419459
Theory And Operation Of Direct Mass Flow Measurement
Author(s): Daniel J. Murphy
Abstract/Introduction:
For many years industry has standardized on volumetric or velocity measurements for flow, primarily because these measurementsare relatively easy to obtain. However, volume changes with temperature. This is easily demonstrated by a mercury thermometer. As the temperature increases the mercury rises, no mercury is being added but the volume is increasing due to the effect of temperature. Volumetric changes can sometimes cause large discrepancies in billing versus receiving records or between inventory, receiving, and product use.
Go to Download Page
Email Reference
Document ID:
9B2E6462
Using The Microcomputer For Flow Calculations
Author(s): Stephen W. Jacovich
Abstract/Introduction:
The application of the transistor to flow measurement calculations resulted in more accurate flow measurements. The use ofthe integrated circuitfurther advanced this trend. Now the microcomputer provides the tool which can result in increased complexity and accuracy in flow measurements. A discussion of the sources of error in a measurement system and the differences between analog and digital methods of computation will be useful in understanding how the use of the microcomputer can result in improved performance. Every component of a measurement system contributes to the total error, although some will contribute more than others. The pipe diameter and orifice plate opening dimensions are nominal within tolerances pressure, differential pressure, and temperature sensors have inaccuracies and flow calculating devices also introduce errors. The inaccuracies introduced by the physical devices are subject to change with temperature and wear. Sensing devices are subject to the same conditions, the errors being caused not only by mechanical tolerances but also by electrical tolerances. The flow calculating device has electronic components which have accuracy tolerances and are subject to the affects of temperatures, humidity, and electrical interference.
Go to Download Page
Email Reference
Document ID:
185C0C02
Fundamentals Of Orifice Meters
Author(s): Cory E. Mahan
Abstract/Introduction:
The ultimate objective of Gas Measurement isthe determination of gas quantities, Two of the most desirable features in any method of quantity determination are repeatability and accuracy. Another desirable feature would be the ability to rfieasure directly the quantities desired in the units desired. In our business it is not always practical, economical, or even possible to measure large natural gas volumes directly. Therefore, in our discussion we will utilize inferential measurement. The most common type of inferential or rate of flow measurement used today in the natural gas industry worldwide is the orifice meter. The orifice measurement principle has been around since Caesars time in the Roman Empire to measure water to households. One of the oldest applications of this concept is a timing device, the hour glass.
Go to Download Page
Email Reference
Document ID:
CB6E2CC0
Testing And Repair Of Large Capacity Diaphragm 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.
Go to Download Page
Email Reference
Document ID:
87A0B107
Ultrasonic Flowmeter - A New Approach To Gas Measurement
Author(s): Michael J. Sceizo
Abstract/Introduction:
Testing of a 24-inch line over several years has demonstrated that a single-path, contrapropagating ultrasonic flowmeter can be calibrated to accurately measure gas flow rates in large diameter pipe lines over a wide range of flows. The following is an adaptation of a paper on this subject, which has been previously presented by Mr. W. D. Munk, Senior Research Engineer, Columbia Gas System Service Corporation, Research Department, Columbus, Ohio. It is presented again here as Part 1 of a two part lecture with the intention of serving as a basis for the second part. Part 2 will consist of actual experience gained during field testing of the device, and will be in an audio/visual format.
Go to Download Page
Email Reference
Document ID:
BE7EE958
Fundamentals Of Rotary And Turbine
Author(s): Richard H. Schieber
Abstract/Introduction:
In the United States and Canada, the bulk of natural gas measurement is handled by four types of meters diaphragm, rotary, turbine and orifice. Figure 1 illustrates the overlapping capacity ranges for the four types of meters, suggesting that for any given application, a choice of at least two and perhaps three meters is possible meter capacity was the only criteria used for selection. The meters in Fig. 1 can be broadly categorized into two groups, the positive displacement type andtheinferential type. This paper will review the differences between these groups as they relate to rotary and turbine meters and discuss the operating principles, characteristics and advantages of each.
Go to Download Page
Email Reference
Document ID:
8B77EE61
How To Manufacture And Inspect And Orifice Meter Tube
Author(s): Ray Kendrick
Abstract/Introduction:
With the recent significant increases in the price of natural gas and other hydrocarbon products (Figure 1), the accurate measurement of these commodities has become of prime importance. Incorrectly constructed orifice meter tubes can introduce measurement errors that normally will favor the product purchaser.
Go to Download Page
Email Reference
Document ID:
9A817209
Flow Measurement By Vortex Shedding Flowmeters
Author(s): O. Q, Webb
Abstract/Introduction:
Acceptance of the vortex flowmeter has increased greatly throughout industry since its introduction over a decade ago. The vortex flowmeter has replaced the orifice, turbine, and magnetic flowmeters due to its high reliability, accuracy and low installed cost. Its versatility in measuring gas, steam, and fluids led to its prominent position in flow measurement today. There are several vendors offering vortex flowmeters. This presentation will provide a general review of all common vortex flowmeters, with particular reference made to the Foxboro vortex flowmeter.
Go to Download Page
Email Reference
Document ID:
26A1A538
Microprocessors In Meter Reading
Author(s): Ronald H. Liss
Abstract/Introduction:
In the utility industry, it is a well known fact that a companys meters represent its version of a retail organizations cash registers. To function successfully and thrive financially, a utility must not only deliver its service but also must be able to bill its customers and. naturally, collect bills from them. For this process to become a reality, there is one other key step that must be performed: Reading the meters so that the use of service registered on them can be translated into billable dollars. Also, as in other segments of business and industry today, utilities must be ever vigilant in their questto improve quality of service while increasing productivity and containing costs. Over the last fifteen to twenty years, the computer has played an increasingly pivotal role in attaining the objectives throughout a wide variety of operations in most utility companies. Advancements in the last few years in microprocessor technology have brought the power of the computer to bear significantly on meter reading activities, particularly with the advent of hand-held units that are light in weight, but heavy in processing capabilities. These strides in the computer field are not surprising and have in fact been occurring ever since ENIAC the Electronic Numencal Integrator and Computer) was developed in 1946 as the first electronic digital computer. Since that time, the progression in enhancements made to computers has been characterized by a reduction in physical size and an expansion in the number of computing tasks that can be processed in shorter time frames.
Go to Download Page
Email Reference
Document ID:
2EC79CFE
Freeze-Up Protection For Instrument And Pilot Gas Lines
Author(s): A. J. Kerr, Jr.
Abstract/Introduction:
Many natural gas systems suffer from time-to-time from bothersome equipment failures or line shut-off due to freezeup. Instrument and regulator pilot supply line freeze-ups can be avoided by the use of flameless, gas-fired catalytic heaters to externally heat the instrument piping and equipment or by adding a packaged, gas-fired catalytic gas heater to preheat the instrument gas stream. Cold, moist climates accentuate the problems of external freeze-up. With the temperature drop accompanying gas regulation, ice often accumulates on instrument gas regulators. plugs the vents and makes the equipment inoperable. Internal freeze-up occurs in instrument gas systems and pilot supply lines because of several factors. Residual water left in a normally dry pipeline after hydrostatic testing is often a cause. Hydrates sometimes form at temperatures as high as 50F. Summer months are difficult for some gas storage systems when the storage pressures are generally at their highest level. Instrument gas taken from high storage gas pressure undergoes a severe temperature drop as the pressure is cut to the instrument gas pressures. Internal freezeup from hydrate formation is a likely possibility.
Go to Download Page
Email Reference
Document ID:
7C40CCE8
Finer Points In Rotary Measurement
Author(s): Vincent P. Oconnor
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.
Go to Download Page
Email Reference
Document ID:
4206607E
Hands On Calibration And Operation Of Mechanical And Electronic Integrators And Chart Processors
Author(s): Terri Kelly, Tommy Moore
Abstract/Introduction:
The orifice meter was developed to measure large volumes of gas at high pressures. Basically, the orifice meter records the pressure of gas before and after constriction by an orifice plate. These pressures are used in the gas flow equation:
Go to Download Page
Email Reference
Document ID:
57C0AAB8
Gylcol Dehydrators As Applied To Production Gas
Author(s): William Nutter
Abstract/Introduction:
Water normally found In field lines Is entrained in the gas, most often in vapor form if water concentration is even moderately high. Gas purchasers are now requiring that the water content must be held down to a minimum standard and perform test sample measurements to determine water content. This method of measurement is commonly known as dew point. With the dew point known it is now possible to refer to tables that establish how many pounds of H2O are in each million cubic feet of gas. This can range from 3# to 200#/MMCF on production gas. A typical contract limit by gas purchasers is 7#/MMCF. The purpose of a dehydration Is to remove saturated water from produced gas to a low enough level to be acceptable to the purchaser, whereas a separator is sufficient to the point of removal of solid liquid forms only.
Go to Download Page
Email Reference
Document ID:
E80B3822
Solar Flow Applications
Author(s): Thomas m. Reilly
Abstract/Introduction:
The need today for companies to reduce costs of chart changing and integrating along with the guaranteed accuracy of metering is the reason solar flow metering is becoming so popular. This is a brief explanation of how solar metering is used at Southeastern Michigan Gas Company for local well purchases, town border stations, as well as large industrial customer sales.
Go to Download Page
Email Reference
Document ID:
C8F70903
Odorization Practices For A Gas Utility
Author(s): David F. Henderson
Abstract/Introduction:
With the introduction of more and more production gas into our piping systems, the need to develop more efficient equipment to odorize low volume systems more accurately and economically, and the absolute necessity of maintaining accurate records, it is imperative that we, as employees involved in odorization, constantly work to improve our companys odorization methods and techniques.
Go to Download Page
Email Reference
Document ID:
FEE2D562
Temperature Compensation Diaphragm Meters
Author(s): James Kobetis
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.
Go to Download Page
Email Reference
Document ID:
07C7DDAD
Overall Measurement Accuracy
Author(s): Howard W. Berghegger
Abstract/Introduction:
The subject title is only one of many which could be applicable, such as: Do Your Measurement Books Balance? Does Your Sales Volume - Your Purchase Volume? Are You Selling All The Volume Youre Entitled to? Do You Really Have Good Measurement? If you honestly answer No to any of the above, then it will be beneficial to explore a few basic reasons for measurement problems. When the word measurement is mentioned, the majority of the gas industry measurement personnel automatically convert their thoughts to a meter. The meter contributes only 1/2 to 1/4 toward the total science of measurement depending on the application.
Go to Download Page
Email Reference
Document ID:
B75648D9
Accuracy And Reliability In Production Gas Measurement
Author(s): Chuck Schoentag
Abstract/Introduction:
Although accuracy and reliability in Distribution gas measurement is expected by natural gas utilities with guidelines set for periodic testing of meter accuracy, it would seem that in Production gas measurement just the opposite is expected by many. There is no question that Production gas measurement is one of the most difficult and costly areas of gas measurement for the independent producer as well as the gas utility. Through proper design and meter selection, accuracy and reliability can become the rule rather than the exception.
Go to Download Page
Email Reference
Document ID:
FBC3950B
Theory And Operation Of Pneumatic Controllers
Author(s): Mike Mckay
Abstract/Introduction:
When one speaks of a controller, most technicians visualize a magic black box which mysteriously manipulates the pressure or flow within our pipeline. It is the objective of this paper to help develop a positive attitude and a basic understanding of the controller, which is absolutely essential to high quality gas control. When we speak of controllers, we need not be confused pertaining to the various types of controller such as: pressure, flow, temperature, back pressure and engine speed control, etc. It is our desire to break the controller down into its primary components and examine each components function. Remember the controller is only a series of mechanical operations.
Go to Download Page
Email Reference
Document ID:
B5615553
Fixed Factor Measurement A New Concept In Measurement?
Author(s): Howard W. Berghegger
Abstract/Introduction:
The term Fixed Factor Measurement was first introduced to the Gas Industry during the 1966 Distribution Conference in St. Louis. This concept is directly related to the performance accuracy of a gas pressure regulator providing constant pressure to a meter. Pnor to this time, when gas was measured at pounds pressure, the meter was either equipped with an integrating, correcting type instrument or a chart record of flowing pressure and indicated metered volume. The instrurhents were expensive and required a constant maintenance program for what was thought to be accurate measurement. Chart records required a very high degree of skill to analyze and divide the recorded volume with applicable pressure increments to calculate standard cubic feet units.
Go to Download Page
Email Reference
Document ID:
B3ADB5FF
An Electronic Primer
Author(s): Wm. P. Somers
Abstract/Introduction:
This paper is meant to be a simple, practical level presentation to make one comtortable with the terms and functions of electronic components and systems used in gas measurement. Topics to be presented are: Basic Electricity Transducers Symbols and Definitions Telemetry Analog Systems Safety Digital Systems Electrical Noise Protection
Go to Download Page
Email Reference
Document ID:
110A2246
Composite Sampling Of Natural Gas
Author(s): Thomas F. Welker
Abstract/Introduction:
The sampling of natural gas has been discussed and studied for many years. Serious testing on the proper sampling methods has been done in a number of locations in the recent past. From these tests, it has been determined that the sampling procedures must be carefully prepared and followed. For a person to collect a representative sample of natural gas, the procedures learned in spot sampling operations must be followed. Continuous sampling is described as a method by which a representative portion of product is removed from a flowing stream and pumped into a sample container during a specific time or volume.
Go to Download Page
Email Reference
Document ID:
1FECC1E0
Fundamentals Of Pressure Control
Author(s): Terry Buzbee
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.
Go to Download Page
Email Reference
Document ID:
E92C6496
Electronics And The Small Utility Can We Afford Not To Get Involved
Author(s): David W. Kimberling
Abstract/Introduction:
Many people panic even today at the very sight of a computer. Many of the smaller utilities are staffed with personnel who have been around this business for a long time. They have amassed a great deal of knowledge and experience pertaining to how their gas system operates. They have dealt with circular charts (orifice meters) all of their lives, and with good reason, in some cases, are very reluctant to let them go. The thought that an impersonal black box, with not so much as even a pen attached, could possibly tell them as much as the circular chart has, breeds an inherent disbelief.
Go to Download Page
Email Reference
Document ID:
8084C2D0
Maintenance And Troubleshooting Of Pneumatic Control Loop Instruments
Author(s): Henry K. Bacon
Abstract/Introduction:
A control loop is comprised of a process (a pipeline for this discussion), a process variable sensing and measuring device, a controller and a final control element (a regulator or control valve). The functions of these parts of the control loop are to determine the present value of the process variable, e.g., static pressure, compare it to a desired value of the process variable and take some corrective action if the process variable is not what an operator or gas dispatcher would like it to be. In Manual operation of thecontrol loop, the operator is the controller through his senses and intelligence. In Automatic operation, the controller is allowed to take over control and the operator is no longer in the control loop.
Go to Download Page
Email Reference
Document ID:
C88F2EB3
Conditioning Natural Gas For Measurement And Transportation
Author(s): Jim Bradley
Abstract/Introduction:
Solid and liquid contamination of natural gas streams can be very costly both in terms of maintenance costs and loss of measurement accuracy. Various designs of filtration and separation equipment have proven successful in minimizing these problems at reasonable cost and low maintenance requirements. A basic understanding of these contaminants and the equipment used to remove them should be very beneficial to personnel involved with the design and/or operation of gas measurement equipment and compression stations.
Go to Download Page
Email Reference
Document ID:
CF631428
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.
Go to Download Page
Email Reference
Document ID:
BB888847
Fundamental Gas Laws
Author(s): Craig m. Linn
Abstract/Introduction:
The Gas Measurement Industry has experienced radical change in the types of metehng equipment used to measure gas flow. Although the hardware has changed, the basic gas pnncipals and relationships have remained the same. For accurate gas measurement, pressure, temperature and volume relationships are of basic importance. These relationships are referred to as the basic gas laws.
Go to Download Page
Email Reference
Document ID:
FD6A920C
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 the 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.
Go to Download Page
Email Reference
Document ID:
57F27721
Monitor Regulators
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 always 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 reliefvalve however, thismethodisfalling 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.
Go to Download Page
Email Reference
Document ID:
8C3481DB
Minimizing Noise And Vibration At Large Volume Regulator Station
Author(s): Richard K. Cole
Abstract/Introduction:
Regulation stations are used in a pipeline system to reduce the internal pressure in a controlled manner. When large flow rates and pressure drops are required, it is very important at the design stage to examine methods of minimizing the amount of noise and vibration created in a regulation run. Noise can easily be predicted with the sound power level (SPL) formula now available from most valve manufacturers. This should never be overlooked i n the selection of a control valve. If noise and vibration are to be minimized, two important criteria to consider are (1) the selection of the control valve, and (2) the configuration of the piping system entering and exiting the regulator settlng(s). Optimum design within these areas will limit the noise, the velocity and the turbulence in the gas stream. Before going further with the design considerations, lets take a closer look at noise and vibration.
Go to Download Page
Email Reference
Document ID:
5B55E7E3
Trouble Shooting Basic Self-Operated And Pilot-Operated Regulation
Author(s): Joseph R. Parch
Abstract/Introduction:
The need to find the solution to problems in regulation has been with us since the first regulator was installed and will be with us until there is no need to use gas pressure to transport gas in adequate volumes. There must have been many blow-outs of the earliest pipelines when operators could not control the gas pressure. This led to having a man throttle a valve to control the volume and pressure by using the sound gas made in passing through the valve opening. There were many problems in using this method and from this, troubleshooting gas regulation began. Today this type of job uses many modern electrical and mechanical devices to tell the conditions of gas flow, but occasionally, it still comes down to a man listening to the sound gas makes in passing through a valve. The trouble-shooter will use the most modern methods and also the most elementary, what is needed most is to arrive at the quickest solution for each type of problem. This is mainly gained through experience, but there are aids to help with the solution, which can be prepared before the problem occurs.
Go to Download Page
Email Reference
Document ID:
2FB39868
Operation And Maintenance Of Catalytic Heaters
Author(s): Jim Reel
Abstract/Introduction:
The use of a catalyst to speed combustion of gas-air mixtures was recorded as early as 1817 by Sir Humphrey Davy. He concluded that hot solids, particulary the platinum group, speed the combustion of gas at relatively low temperatures. Further research in 1912 by Bone and collaborators into the discovery by Davy determined that: 1. All surfaces possess the power (in varying degrees) to accelerate gaseous combustion at temperatures below the ignition point. 2. Acceleration is dependent upon absorption of gas by the surface. 3. Tests determined that platinum was a very good catalyst for surface combustion and was proven to be most dependable as a catalyst.
Go to Download Page
Email Reference
Document ID:
B98DD330
Interpreting Meter Charts
Author(s): Carl Freeman
Abstract/Introduction:
Because of the many variables that can, and do, affect the recording or production on a chart there are a great many instances where personal interpretation is a necessity in order to achieve accuracy in measurement. The ability to recognize a problem and the correct interpretation of the problem is not only important for measurement accuracy but can also be a useful tool for production personnel in the field. There are several areas that must be considered when interpreting meter charts. These areas include defective instruments in the field, sudden and unpredictable changes in the weather, human error and the problems caused by the peculiarities of a well in production.
Go to Download Page
Email Reference
Document ID:
A4197535
Fundamentals Of Flow Computers
Author(s): E. J. Dupuis
Abstract/Introduction:
A digital flow computer is much like a large scientific computer scaled down and streamlined to perform specific functions and calculations. It contains special circuitry that allows it to receive electronic signals from other devices representing flow conditions, ambient conditions, or other process variables. The flow computer uses this information to perform calculations and will output the final calculation data by some means to allow human interface. Some computers even use the calculated data to perform some type of process control via special output circuitry. Prior to beginning a discussion on flow computers, it is necessary to define common terminologies related to the subject.
Go to Download Page
Email Reference
Document ID:
C4D771B4
Inspection, Maintenance & Testing Of Orifice Meters
Author(s): Calvin E. Whiteside
Abstract/Introduction:
The orifice meter is one of the oldest devices known for measuring natural gas with a high degree of accuracy. When a good program of maintenance and testing procedure is followed, this instrument will perform the functions it was designed to do. Because of the energy crisis and the higher cost of natural gas, the most important job in our industry is an accurate accounting and measuring of natural gas. All segments of the industry have responded to the challenge. The manufacturers of meters have continued to make improvements in their products, providing more dependability and greater accuracy in their products. Gas companies have also spent large sums of money and time to develop greater accuracy in gas measurement.
Go to Download Page
Email Reference
Document ID:
7C183ACC
Multiport Averaging Pitot Tube In Gas Measurement And Control
Author(s): Norman A. Alston
Abstract/Introduction:
Just because a flow measurement device is complex and/or expensive does not automatically mean that it is the best or most accurate. Oftentimes the most simple device is just as good and accurate and frequently even better Economic pressure encourages the emergence of better all-around devices with greater reliability and accuracy. These and other factors have brought to the fluid flow measurement industry the Multiport Averaging Pitot Primary Flow Measurement Device, This refined version of the basic pitot tube, the same as the orifice and other head-type primaries, is based on the same standard hydraulic equation, continuity equation and Bernoullis Theorem. Thus, an extension and improvement of proven concepts and device makes available to the industry a primary flow measurement device which offers many benefits, including a simple design, with equal or better performance for fluid flow measurement and process control applications.
Go to Download Page
Email Reference
Document ID:
BEB2256E
Computerization Of Standard Meter Operations
Author(s): Robertj. Rozum
Abstract/Introduction:
COSMO is the Computerization of Standard Meter Operations. This unique system provides the solution to meter testing, shop floor control, inventory and information exchange problems that have plagued our industry for years. By employing error free bar code labels that contain significant information in a concise format, meters can be tracked from the day they are purchased or from the point they are renioved through testing, inventory and eventual placement back in service. The system enables the utility to initiate new and validate existing meter records, track the meters progress through the plant, monitor productivity, report continuously the status of inactive and active meter inventory, and provide on-line data for reporting and resolving billing discrepancies and complaints.
Go to Download Page
Email Reference
Document ID:
1966E5F2
Accounting For Appalachian Production - A Producers Viewpoint
Author(s): Roger A. Murray, Janet S. Snyder
Abstract/Introduction:
The Appalachian Basin has been a desirable region for investment in the exploration and production of natural gas. Major reasons making this areafinancially attractive include shallow wells (less than 6,000 feet), long production life (in excess of 20 years), high BTU content gas, and a consumer market close to the East Coast. To maintain the successful economic growth of the industry in this region, new reserves must be discovered and current and future wells must be produced to their maximum potential. In order to discover, produce, and develop these reserves, all departments within a producing company must work together and share all available information. One key item to be shared is the production data.
Go to Download Page
Email Reference
Document ID:
E4B6D926
Low Power Field Flow Computers Part 1
Author(s): Tom Fritts
Abstract/Introduction:
The primary goal of gas measurement systems is to provide accurate, timely production information for accounting purposes. If gas prices rise in the future as fast as predicted, this goal is sure to assume increasing importance. New standards of accuracy will likely be necessary to satisfy both buyers and sellersthatlransfersof ownership are fair and equitable. With the prospect of high interest rates, more attention will likely be focused on reducing the delays between field measurement and billing or invoicing. The vast majority of field production systems utilize the timeproven orifice measurement method and are committed to circular chart recorders as the secondary measurement device. It is by no means certain that it is good economics to improve these systems sufficiently to satisfy the demands for increased accuracy and shorter reporting periods that are expected. The increased costs necessary for more frequent chart changing and processing, and equipment calibration, inspection, and maintenance may easily offset the marginal gains that are obtained.
Go to Download Page
Email Reference
Document ID:
56D41069
A Detailed Look At Volume Calculation
Author(s): Steven T. Demers
Abstract/Introduction:
Displacement meters measure quantities of gas in volume units at the pressure and temperature conditions at the meter. In order to convert the volume units to contractual base conditions of pressure and temperature, Boyles and Charles laws for ideal gases must be applied. The equation for converting the volume units at measured conditions (m) to contractual base conditions (b) is:
Go to Download Page
Email Reference
Document ID:
BD893D78
Orifice Flow Measurement
Author(s): C. R. Samples
Abstract/Introduction:
Escalating costs of raw materials have caused petrochemical plant management to become increasingly concerned about product accountability. This concern can only be addressed if the design engineer has the capability to evaluate measurement uncertainties of new and existing flow metering systems with which he is associated. Uncertainty is usually defined as the maximum error that could be expected with a predetermined confidence level (normally 95% or 2-standard deviation), Recognizing that the square edge orifice has been and will continue to be used extensively for process measurement and product accountability, this paper describes a computer program which has been developed for general use that determines total flow uncertainty of an orifice measurement system.
Go to Download Page
Email Reference
Document ID:
BF6A6DB7
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 astandardcubicfoot of natural gas and a second is the lack of an Industry standard for diaphragm meter capacity ratings at elevated 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.
Go to Download Page
Email Reference
Document ID:
5C9B4B6C
The Fluid Data User Friendly Calorimeters And Process Chromatographs For Energy Measurement Systems
Abstract/Introduction:
Once the valve configuration and flow characteristic are selected, the control valve can be sized for capacity. Sizing is exactly what the name implies it is the process whereby you select the valve size (capacity) best suited to control your process. You can calculate the valve capacity required after determining the maximum and minimum flow rates of the system and the pressure drops at each flow rate. Capacities are listed in all manufacturers literature. They are expressed in gallons per minute at 1 psi differential pressure for liquids, or in standard cubic feet per hour at 1 psi differential pressure for gases. The sizing coefficient is expressed as Cv for liquids and Cg for gases. Some manufacturers do not use a specific coefficient for gases. Instead, they employ a conversion method to handle compressiblefluids using the liquid flow sizing coefficient Cv.
Go to Download Page
Email Reference
Document ID:
20938905
Latest Revisions Of AGA #3
Author(s): David W. Kimberling
Abstract/Introduction:
Some sixty years ago, in May of 1924, the Board of Directors of the Natural Gas Association directed its Main Technical and Research Committee to establish a new subcommittee to be known as the Gas Measurement Committee The duties assigned to this committee were as follows: a. To determine the correct methods of installing orifice meters for measuring natural gas. b. To determine the necessary corrective factors and operative requirements in the use of orifice meters. using natural gas in all experimental work. c. To secure the cooperation and assistance of the National Bureau of Standards and the United States Bureau of Mines, and to secure, if possible. the assignment of Members of their staffs to the Gas Measurement Committee to assist in this wori. The new committee held its first meeting in November 1924. A Preliminary Report was issued by the committee in 1927, revised in 1929, and what we know as Report No. 1 issued in 1930. The issuance of this report followed six years of research work on orifice meters.
Go to Download Page
Email Reference
Document ID:
3C2E4FA9
An Update On Remote Meter Reading
Author(s): Raymond G. Kremer
Abstract/Introduction:
Im amused when every once in a while I pick up a newspaper or magazine and come across an article by some science editor proclaiming the latest thing in technology to be the remote reading of utility meters, be they water, electric gas or whatever. My thoughts inevitably stray to the Remote Reading Device patented on May 27th, 1890 - So whats new under the sun? Not very much Im afraid! The term Remote Meter Reading is often misused as it has been in the title of this class, to describe all methods of reading utility meters other than by conventional meter reading methods. This is not true as will be explained later and the various techniques and the equipment used in their implementation will be described briefly.
Go to Download Page
Email Reference
Document ID:
ED58EC62
Rotating Vane Gas Meters
Author(s): Richard H. Schieber
Abstract/Introduction:
The rotating vane gas meter, manufactured by American Meter, is one of two rotary meter designs on the market today. The lobed impeller design, although exhibiting many common rotary meter characteristics with the rotating vane design, is not specifically discussed in this paper. The rotating vane meter is a positive displacement measuring device used in production, distribution, and industrial gas measurement to indicate total actual gas volume. When combined with a variety of correction devices or techniques, the meter is part of a total measurement system that indicates corrected total volume, corrected for the volumetric effect on the gas of temperature and pressure conditions. This paper will describe the fundamentals of rotating vane technology, and give comparisons with the nearest competing metering designs diaphragm meters and turbine meters), in an attempt to describe the best applications for this versatile rotary meter.
Go to Download Page
Email Reference
Document ID:
8B917C51