Fundamentals Of Gas Laws
Author(s): John Chisholm
Abstract/Introduction:
In the gas industry a standard unit of measure is required. In the English system it is the standard cubic foot. In the metric, it is the standard cubic meter. This standard unit is the basis of all exchange in the gas industry. When the unit of purchase is the energy content (BTU) we achieve it by multiplying the BTU content of a standard cubic foot times the number of cubic feet delivered to the customer. So we must obtain standard cubic feet or meters. A standard cubic foot is defined as one cubic foot of gas at a pressure and temperature agreed upon by the buyer and seller. Common standard conditions are 14.73 psia and 60 Fahrenheit. The gas passing through a meter is rarely at standard conditions. It is necessary to convert the gas in the meter from the metered conditions to standard cubic feet. The tools we have for relating volume to pressure and temperature are Equations of State or, simply, the Gas Laws.
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Document ID:
1369A1D0
Basic Properties - Natural Gas
Author(s): John H. Batchelder
Abstract/Introduction:
Natural gas is misunderstood by many. It is believed by some that all gas is a liquid that is pumped into automobiles or into tanks and is used as a fuel. It is thought of as a dangerous material that will blow up easily. Others do not differentiate between LP gas, natural gas, or gasoline - They are all the same thing, right? While it is true that the above mentioned materials are all made up of the same basic components, each has its own physical and chemical characteristics.
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Document ID:
D8757DA8
From The Wellhead To The Burner Tip: A System Overview
Author(s): John Rafferty
Abstract/Introduction:
This paper is presented at the Appalachian Gas Measurement Short Course - Fundamentals Section. The paper is designed for the first year student to understand the basic flow of natural gas and the terminology utilized from Production and Storage areas to end use by consumers. Specific focus is given to history of natural gas, gas transmission, city gate stations, and distribution systems.
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Document ID:
8B7072F1
Pressure Control Basics
Author(s): Paul R. Sekinger
Abstract/Introduction:
Pressure control is the fundamental operation of all natural gas delivery systems. It provides a safe and reliable energy source for manufacturing and heating systems throughout the world.
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Document ID:
E713AD56
Fundamentals Of Gas Measurement
Author(s): Pat Donnelly
Abstract/Introduction:
Samuel Clegg made the first practical gas meter in England in 1815. It was a water-sealed rotating drum meter that was improved in 1825 however, it was still very costly and very large. Thomas Glover developed the original diaphragm meter in England in 1843. It consisted of two diaphragms, sliding valves and linkage. T. S. Lacey patented the pre-payment meter in 1870. The most significant change to diaphragm meters over the years has been in the materials of construction. Brass parts have been replaced by plastic, and leather diaphragms have been replaced with synthetic rubber. A rotary piston meter was invented in the late 1800s, but it was primarily used a blower. In the 1940s a Roots- Connersville dimensional rotary meter was used. The style of rotary meter in use today was first used in the 1960s in the cast iron version, the extruded aluminum style came out in the 1970s. The modern turbine meter was developed in the 1970s. It has had minor modifications over the years, but the basic operation is the same. Ultrasonic measurement was first developed in the 1980s and has been refined over the years.
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Document ID:
F53512C1
Rotary Displacement Meters Basics
Author(s): Todd Willis
Abstract/Introduction:
Natural gas measurement today is accomplished through the use of two different classes of gas meters. These are inferential type meters, which include orifice and turbine meters, and positive displacement meters, which include diaphragm and rotary displacement meters. The inferential type meters are so-called because rather than measuring the actual volume of gas passing through them, they infer the volume by measuring some other aspect of the gas flow and calculating the volume based on the measurements. The positive displacement type meters are so-called because they measure the actual volume of gas displaced through them. The rotary positive displacement meter has been in existence for over 75 years. Its reliability, rangeability, longterm accuracy, and ease of installation, maintenance and testing have made this meter a favorite among gas utilities for billing purposes in industrial and commercial applications. Rotary meters have also gained popularity in the production and transmission markets.
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Document ID:
A8B0CC25
Factors Affecting Orifice Accuracy
Author(s): Reji George
Abstract/Introduction:
Orifice Measurement is a proven method of gas measurement. As an industry, we have been talking about this metering method and problems associated with it for more than seven decades. In 1939, Mr. C. A. Smith (Superintendent of Gas Measurement, West Virginia Gas Corporation, Charleston, West Virginia) speaking at the Second Annual Appalachian Gas Measurement Short Course, said the following about orifice plates: The orifice plate is the main part of the orifice meter, and must not be overlooked. You can have your meter gauges in the best possible working condition, but if an inferior, warped, or dirty plate, or dull edged orifice is used, you can have inaccurate results in gas measurement. That statement still holds true in 2003. This paper will highlight a few maintenance practices that will support good orifice measurement in addition, some errors associated with the primary orifice element will also be discussed.
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Document ID:
256FF3A4
Onsite Proving Of Gas Meters
Author(s): Daniel J. Rudroff
Abstract/Introduction:
With the increased use of Natural Gas as a fuel, higher natural gas prices, and the new federal regulations, buyers and sellers of natural gas are seriously looking at ways to improve their natural gas measurement and reduce the unaccounted for natural gas. An error in measurement of only one tenth of one percent (0.1%) on 100 million standard cubic feet per day of Natural Gas selling at 5.50/MCF will cause an over or under billing of 200,750.00 in one year. This will easily pay for a proving system. The energy (Btu) in one barrel of oil is equivalent to approximately 5,600 cubic feet of natural gas. At 5.50 per thousand cubic feet, the natural gas equivalent of one barrel of oil costs 30.80 or more than the cost of an average barrel of oil. In the petroleum industry no custody transfer liquid measurement system would be used without a method to prove the meter. The prover would be part of the measurement system or there would be connections provided on the measurement skid to connect a portable prover.
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Document ID:
7594A265
Flowmeter Installation Effects
Author(s): Thomas Kegel
Abstract/Introduction:
Flowmeter installation effects are the result of differences between the conditions in the field and those in a calibration facility. This paper provides an introduction to two of the most common field conditions: velocity profile distortion and swirl. The paper is divided into the following section: A simple description of the velocity profile. The profile and swirl produced by single and double elbows. Some effects on orifice, turbine and ultrasonic meters. The use of flow conditioners.
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Document ID:
C45F04FA
Operation And Maintenance Considerations For Multi-Path Gas Ultrasonic Meters
Author(s): James W. Bowen
Abstract/Introduction:
Ultrasonic Meters have unique outputs that enable remote condition monitoring to insure continued gas measurement integrity. Integrating a monitoring protocol with these diagnostic outputs into a Routine Maintenance program is a developing art that still requires some subjective evaluation: Setting reasonable alarm limits remains ill defined by most manufacturers, including Instromet, because our understanding of Ultrasonic meters outputs in an operating environment is primitive, but growing as acceptance of ultrasonic custody measurement proliferates.
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Document ID:
69754F27
Wet Gas Through Two Phase Complete Measurement
Author(s): Daniel J. Rudroff
Abstract/Introduction:
Wet gas and wet gas metering has always been done. But only recently has any attempt been made to define wet gas and a method to measure it. Dr. Parviz Mehdizadeh in a white paper, API project 2002-100094 presents the following definition of wet gas. Dr. Parviz states in the white paper that wet gas can be simply defined as gas, which contains some liquid. The amount of liquid can vary from a small amount of water or hydrocarbon to substantial amount of water and hydrocarbon.
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Document ID:
CB0E5C22
Whats In Your Pipeline? And( Do You Really Want To Know?)
Author(s): David J. Fish
Abstract/Introduction:
With the current demand for improved technologies in the area of natural gas measurement, the rush to the market place is raising as many questions as it is answering. In the last 25 years, the natural gas pipeline industry has transitioned from the supplier of clean, dry gas to the mover of billable gas energy clean and dry or dirty and wet. Designing and creating improved products for the measurement of volume and quality has provided new challenges as the marketing and transportation of natural gas has changed. Perhaps the single major issue that has created an interest in ascertaining the total picture of the natural gas pipeline system is wet gas. The definition of wet gas as gas with more than 7 lbs. water per million cubic feet is almost history. Wet gas metering is redefining how we talk about wet gas.
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Document ID:
5BC6BC35
Effects And Control Of Pulsation In Gas Measurement
Author(s): George L. Bell, Sr.
Abstract/Introduction:
Pulsation created by compressors, flow control valves, regulators and some piping configurations are known to cause significant errors in gas measurement. In recent years the Pipeline-and Compressor Research Council (PCRC) now know as (GMRC) Gas Machinery Research Council, a subsidiary of the Southern Gas Association, commissioned and funded various pulsation research projects at Southwest Research Institute (SWRI) in San Antonio, Texas. This research culminated in the publication of several technical papers, including the April 1987 PCRC report 10.87-3 titled Pulsation and Transient-induced Errors at Orifice Meter Installations and a report, An Assessment of Technology for Correcting Pulsation Induced Orifice Flow Measurement dated November 1991.
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Document ID:
A694C531
Life Of An Appalachian Gas Well
Author(s): Timothy L. Altier
Abstract/Introduction:
Natural gas was once an unwanted byproduct of oil production. Since it is the gas that pushes oil and brine to the wellbore, the gas was flared, sometimes in great quantities in order to produce the oil. No effort was made to conserve the gas so, ironically, the field pressure would decline rapidly and most of the oil would be left in the reservoir.
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Document ID:
C8577C5F
Performance Evaluation Of Gas Storage Wells Through Field Testing
Author(s): Alan Brannon
Abstract/Introduction:
Gas Storage wells are continually evaluated by comparing well tests over time to determine if there has been any deterioration in performance. This is typically accomplished by performing certain types of tests on a pre-determined schedule. One of these methods involves performing a flow test where a well is flowed at several rates for certain durations. This type of testing is referred to as back pressure testing, where the well in question is tested at these predetermined rates and static shut in pressures before each of the flows are recorded and the final end of duration flowing pressures and rates are recorded. These tests can be performed while on injection or withdrawal but are typically performed on injection when the source gas can be controlled and the demands on the system are not as critical as they are during the withdrawal season when pipeline supply is being supplemented by storage withdrawals. Well tests that are performed on a continual basis can be collectively reviewed by the technician or engineer to determine if degradation in performance is indicated or if the well has responded to remedial operations. Also, these welltests can be used to predict overall storage field performance under certain conditions to help in deciding if various storage services are viable.
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Document ID:
6882E998
Coalbed Methane Resources In Pennsylvania: An Overview
Author(s): Antonette K. Markowski
Abstract/Introduction:
National demand for natural gas is increasing, with the resource now heating 50 percent of United States homes and fueling 95 percent of new power plants (Pinsker, 2000, p. 34). By 2020, demand for natural gas is forecast to increase by 53 percent coupled with the fact that during the 1990s United States production capacity did not keep pace with demand growth (Holtberg and others, 2000). This large, domestic shortfall was met by Canadian natural gas imports (American Gas Association, 2000). Another way to reduce this deficit is to fully develop known domestic reservoir basins and explore for untapped sources of natural gas, one of which is coalbed methane (CBM). CBM or coal seam natural gas is one of the fastest-growing energy plays in North America today.
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Document ID:
EC31DCF5
Underground Storage Of Natural Gas
Author(s): Timothy D. Maddox
Abstract/Introduction:
Most people have never heard of natural gas storage. Even those working in related areas of the gas industry may not have had the opportunity to become completely familiar with it. Storage has historically been a unique but little discussed discipline. With recent changes in Natural Gas Industry regulation, storage has become an important service for utilities to economically serve markets. It is being discussed more frequently, therefore, I have attempted herein to provide the basics, or the what, why and how of underground natural gas storage.
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Document ID:
81000BAA
The Basics Of Well Tendering
Author(s): Twain Faulkner
Abstract/Introduction:
The well tenders job duties are classified into the following areas: 1. Safety 2. Field Integrity and Inventory 3. Deliverability Maintenance 4. Troubleshooting 5. Operations
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Document ID:
B84FF836
Field Experiences With V-Cone Technology
Author(s): Philip A. Lawrence
Abstract/Introduction:
The V-Cone differential pressure meter was introduced in the early 80s. Initial customer review of the technology at that time was skeptical due to the radical change in emphasis of the flow regime from a central portion of a closed conduit (orifice plate) to fluid velocity profile around a centrally mounted cone at that time unheard of. Today much of the skepticism has passed due to the acceptance of large number of in field units 40,000 This paper describes the principles and field use of the V-cone D.P. flow meter used in the role of wellhead metering, injection measurement allocation metering / custody transfer both topside and sub-sea in on-offshore oil and gas production applications.
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Document ID:
C5D3AD63
The Impact Of API 14.1 And Other Standards To Practical Considerations For Gas Sampling
Author(s): David J. Fish
Abstract/Introduction:
The need to be able to take a representative sample of a hydrocarbon product is necessary to ensure proper accounting for transactions and efficient product processing. The various sampling methods that are available and the options and limitations of these methods are investigated the most appropriate equipment to use the reasons for its use and correct installation of the equipment are also addressed.
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Document ID:
A3B9C974
Interchangeability Of Natural Gas Sources
Author(s): Henry W. Hank Poellnitz, III
Abstract/Introduction:
Until recently, the term gas quality usually referred to a gass effect on the internal corrosion of the pipeline. Most of these corrosion-related gas quality issues are well documented and understood. In recent years, gas quality has taken on new meaning for the gas industry for three reasons. 1) LNG imports from around the world appear to be part of the long range plan for meeting the North American natural gas supply needs again, and pipelines are working to determine LNGs effects on its existing customers. 2) The margins in gas processing have recently been strained by high gas prices, and many processing plant have shut down or reduced their level of processing, causing operational and safety problems for pipeline operators and their customers. 3) Power plants designed and budgeted a few years ago are beginning operation, and gas quality affects how power generators comply with EPA regulations and equipment specifications.
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Document ID:
6AFC161A
Odorization: A Discussion Of Code Compliance And Liability Issues
Author(s): David E. Bull
Abstract/Introduction:
A question often posed concerning odorization is Why odorize? This paper discusses two answers to that question: Regulations and Liability. The first answer, Regulations, is an easy one. Pipeline safety regulations promulgated by the Department of Transportation Office of Pipeline Safety (OPS) contain specific requirements in 49 CFR 192.625 that gas contain an odor. So, by law, operators are required to deliver odorized gas. The second answer, Liability, also seems easy. Odorization of a gas system is done with a single purpose in mind: Provide the public with an effective warning device to alert them when there is a possible problem. Difficult to document, yet it continues to prove itself effective as gas companies continue to receive odor complaints on a regular basis.
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Document ID:
90425404
Operations And Maintenance Considerations For The Use Of Odorant In Custody Transfer
Author(s): Jan Strmen
Abstract/Introduction:
The easily recognizable smell of odorants in natural gas signal leaks in transport or distribution pipelines, breakdowns of natural gas appliances or failures in odorization equipment itself. Odorizing of natural gas thus provides a safety net for the public and the natural gas industry. United States and Canada legislated odorant use in 1937 after a tragic accident in London, Texas claimed 293 lives, mostly school children. The main advantage of using mercaptan blends as odorants is in their extremely low odor threshold. For example odor threshold value for tertiary butyl mercaptan, one of the main odorant blend components, is about 0.4 parts per billion. Concentrations of such odorants in natural gas are typically around two parts per million.
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Document ID:
505B7952
The Proper Application Of Rotary Meters
Author(s): Kevin C. Beaver
Abstract/Introduction:
This paper highlights several rotary meter performance characteristics. These characteristics profile a rotary meters capabilities in a wide array of applications from production to transmission, and distribution. Most of the characteristics have minimum standards adopted by agencies like AGA or ASTM. Ill identify these standards, and incorporate them-where applicable-into my paper. In discussing these characteristics, I hope to give the reader a better understanding of the capabilities of rotary meters, and how the gas industry assesses these characteristics.
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Document ID:
BC4270E4
Differential Testing Of Rotary Meters
Author(s): R.A. Ron Walker
Abstract/Introduction:
Over a hundred years ago, the Brothers Root were searching for an innovative way to convert water into power. Their search led to two figure eight shaped lobes. Legend has it that the lobes did not pass water efficiently, but when the contraption blew one of the brothers hats into the air they knew they had an industrial strength blower. Nearly eighty years ago, the Roots Brothers Blower Company decided that their basic design, when a counter replaced the blower motor, could be used as a gas measurement device. The era of rotary gas measurement was born.
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Document ID:
80B17969
Troubleshooting Large Capacity Diaphragm Meters In The Field
Author(s): Dave Shepler
Abstract/Introduction:
Those of you who have, or will have, experience in troubleshooting diaphragm meters, know it can be very frustrating at times trying to figure out the problems that can be encountered in the field. This presentation will hopefully address most of those problems and provide some solutions.
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Document ID:
B4B33A04
Gas Meter Proving: The Equipment And Methodology Used Today In The Natural Gas Industry
Author(s): Gregory A. Germ
Abstract/Introduction:
To determine the accuracy of a natural gas meter, a known volume of air is passed through the meter, and the meter registration is compared against this known volume. The known volume of air originates from the meter prover. In earlier times, the gas meter prover was a stand-alone device (usually a bell-type prover), manually operated without any electronics or automation. Today, the majority of gas meter provers are fully automated computer controlled and operated, and responsible for other job functions besides the proving of gas meters. The bell-type meter prover - though still commonly used in the industry - is not the only kind of meter prover used today.
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Document ID:
6E68A630
Meter Inventory Management
Author(s): Gregory S. Veraa
Abstract/Introduction:
Meter value is not just the cost of the meter. Meter ownership starts at the selection of a meter vendor and ends when the meter is retired from service and scrapped. It is important to manage the meter inventory and meters in service to maximize their value to the utility and to protect a valuable asset. By metering the gas delivered to customers, the accuracy of the meter and its in-service performance are critical to the revenue of the utility. In order to maximize the value of the meter to the utility it is necessary to evaluate the whole life cost of ownership of the meter. This paper presents information that will be useful in managing meter inventory, including such topics as new meter type acceptance, new meter acceptance testing, in-service performance testing, selecting a meter vendor, optimizing inventory levels, and repair versus replace decisions. Factors that should be considered in evaluating the cost and value of the meter and other practical information is also presented.
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Document ID:
4A4A65A7
Mass Meters For Gas Measurement Class #1200
Author(s): Karl Stappert
Abstract/Introduction:
Coriolis meters have gained worldwide acceptance in liquid applications since the early 1980s with an installed base or more than 350,000 units. Newer designs have shown greatly improved low-flow sensitivity, lower pressure drop, and immunity to noise factors which now enable their successful use in gas-phase fluid applications. With more than 20,000 units on gas around the world, measurement organizations around the world are involved in writing standards for this emerging gas flow technology.
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Document ID:
8637CA29
Diagnostic Indicators
Author(s): Kevin L. Warner, Charles W. Derr
Abstract/Introduction:
New for the sake of new and old for the sake of familiarity may in either case promote the waste of resources. It has now been a number of years since deregulation and the move to open sales, transportation and hubs has resulted in fierce competition. Operational cost savings, where practical, are a necessary part of success and indeed, survival. Technician is an overly generalized and many times unappreciated title. Technicians are the field professionals that really make systems for control, compression, dehydration, odorization, and measurement a success or bad venture and highly influence a gas companys prosperity This document focuses on a highly proven before release new technology that offers great savings to gas companies and provides some new challenges to the field professional. Ultrasonic meters are easy to learn and they add some new dimension and value to the users measurement experience. Gas ultrasonic meters, (USMs), are here to stay.
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Document ID:
4A00EF80
Selection And Sizing Of Control Valves For Natural Gas
Author(s): Carol L. Nolte
Abstract/Introduction:
The purpose of this paper is to help the user understand the information needed to properly select and size a control valve for natural gas service. With so many different manufactures of control valves we wont focus on one however the information listed is required by all manufactures in order to provide you with the best valve for the application. Most manufactures will assist you in sizing your application. The first step in sizing a control valve is to determine the required Cv or capacity required through the control valve at different operating conditions. It is not enough to size for one condition, rather all the conditions must be considered.
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Document ID:
BDF5A42E
How To Select The Proper Control Valve For Your Application
Author(s): Mike Racine
Abstract/Introduction:
The purpose of this paper is to provide guidance in selecting the proper type of control valve for natural gas pipeline control applications. To enable the reader to make an educated selection the different types of control valves will be discussed to demonstrate their primary features, differences, and capabilities. Additionally, standard practices will be reviewed covering acceptable design practices concerning maximum pipe velocities, control valve exit velocities, noise levels, and station equipment layout.
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Document ID:
6BE8C02D
Gate Station Design
Author(s): John Rafferty
Abstract/Introduction:
The City Gate or, Take, Station, is the interchange of natural gas between: Two interstate pipelines An interstate pipeline and a local gas distribution company (LDC) An interstate pipeline and a large industrial end user (usually a power plant) The City Gate station is one of the more complex designs a natural gas engineer will deal with in the course of a career. Like all projects, a properly designed and constructed gate station begins with good preliminary engineering. In preliminary engineering, all of the major project goals and hurdles are defined. If the preliminary engineering document is written properly, it will serve as the backbone for the entire project.
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Document ID:
A344A41D
Freeze Protection For Natural Gas Pipeline Systems And Measurement Instrumentation
Author(s): David J. Fish
Abstract/Introduction:
Consistent and continuous pipeline operations are key and critical factors in todays natural gas pipeline industry. The competitive nature of the business, together with the strict rules and regulations of natural gas supply, mandate that companies stay on top of all operational parameters that could cause interruption or complete shut-down of the natural gas supply to customers. Identifying what may ultimately cause problems is a first step to controlling and eliminating those problems for the supplier. The natural phenomenon of freezing is a common occurrence in the operation of a natural gas pipeline system. Whether the gas is produced gas from a crude oil well, or natural gas from a gas well, the possibility for hydrates and the resultant problems, is real. Freezing is a potential and serious problem starting at the production well head through the last point in the customer delivery system.
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Document ID:
5676677E
Overpressure Protection
Author(s): David C. Hiatt, Donald E. Holtman
Abstract/Introduction:
In a gas distribution system, each piece of pipe must be protected against overpressure or exceeding the maximum allowable operating pressure (MAOP) plus allowable build-up. This includes all feeder line, distribution mains and all service lines. In some cases the operating company will apply a maximum pressure to a pipeline that is less than the MAOP. Systems that have a history of corrosion problems or those that have operated for years at a lower pressure may be assigned a maximum operating pressure (MOP) that the company considers safe, and will install an overpressure device to protect from exceeding that pressure. Requirements for the design, operating, maintenance, inspection and testing of gas pipelines and their components are in the contents of Part 192, Title 49, Code of Federal Regulations. These laws come under the jurisdiction of the Department of Transportation (DOT).
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Document ID:
74D36D66
Flexible Element Regulators
Author(s): Rick F. Mooney
Abstract/Introduction:
Regulators that utilize a single rubber element that performs the same function as both valve and actuator are known as flexible element regulators. The first type of flexible element regulator was developed and manufactured by the Grove Regulator Company in the 1950s. The Grove Flexflo was referred to as an expansibletube type because a tube or rubber sleeve was stretched over a slotted metal core separating the inlet and outlet of the regulator. The tube expanded when flow passed through the regulator. Expansible-tube type regulators had many features that contributed to their popularity:
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Document ID:
5D27741C
District Regulator Station Design - A Case Study
Author(s): James P. Davis, Scott A. Laplante
Abstract/Introduction:
This paper outlines a recently developed design concept for buried district regulator stations. It will focus on the research and design findings used by NSTAR to develop the smallest practical prefabricated buried vault considering the following: 1. Standardization of design 2. Regulator sizing flexibility 3. Code mandated venting requirements 4. Installation flexibility 5. Best egress and ergonomics 6. Material selections 7. Cost savings A process improvement team worked three years to develop an approach that has rewarded NSTAR with designs and final installations warmly received by field technicians while saving costs in both capital and O&M.
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Document ID:
9598A919
Controller Fundamentals And Tuning
Author(s): Greg Thomas Shumate
Abstract/Introduction:
It is not very easy to start talking about PID controllers. But, once we get started we will go over many aspects of control and how PID controllers help us. Do we start with what they are used for, or how they work? Or for that matter, what is PID? That might be a good place to start. Proportional - Integral - Derivative. Thats it! PID. In this paper we will go over the practical aspects of using and tuning mechanical, pneumatic, and electronic controllers. In our natural gas business nearly all control systems maintain pressure. However, there are many systems that require flow, temperature, level, blending and other types of control. The basic reason for using a controller is to automatically maintain the desired level or value of a given product being supplied to a user. The easiest place to start is with the most popular controller, by far, in our industry - a spring-loaded regulator.
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Document ID:
F519133E
Field Communications For Ldc Pressure Monitoring
Author(s): Michael Marsters, Matthew Pawloski
Abstract/Introduction:
It seems that the next logical step for our increasingly intelligent correctors, data loggers and flow computers would be to give them the ability to communicate. This would seem natural, with the growing number of personal computers in the gas industry and the tendency toward automatic data collection for large industrial and commercial customers. New challenges arise almost every day in the timely collection of billing data from interruptible service monitoring to the daily balancing of transportation gas. Already, many electronic correctors are being used to store load profile and other timerelated data in onboard memory. This can be downloaded into a handheld terminal, a portable computer or into a remote computer via telephone modem link. It is now not only desirable to get information out of the field instrumentation. New information can be fed into the corrector, as well. For example, we can now make our supercompressibilty even more dynamic.
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Document ID:
161D6F15
Automating Gas Measurement
Author(s): Richard L. Cline
Abstract/Introduction:
Since the discovery of oil and gas and the advent of commercial conveniences, which use oil and gas, companies have been confronted with the need to accurately measure the oil and gas bought and sold in the marketplace. And, as usual, the technology available at the time was brought to bear on the measurement process.
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Document ID:
8F28C3E2
Proper Operation Of Gas Detection Instruments
Author(s): George Lomax
Abstract/Introduction:
This paper will address the operation, maintenance and calibration for a number of instruments available today for the detection of combustible and toxic gases. The applications for these various instruments will also be discussed. This will include the investigation of odor complaints on a customers property, leakage survey applications, and other safety requirements.
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Document ID:
29107FB6
Vortex Technology Prevents Freezing In Gas Pressure Control
Author(s): Lev Tunkel
Abstract/Introduction:
The new concept of heating developed by Universal Vortex was utilized to increase temperature of a pilot gas upstream of the pilot orifice and for spot heating in gas pressure regulation. The proprietary Vortex Heater (VH) decompresses highpressure gas flow, as the gas expands in VHs inlet orifice, and converts gas flows internal energy into a highly intensive thermal flux. The generated heat is then applied to indirectly heat a separate pilot gas flow and for self-heating to secure a non-freeze gas decompression in the VH.
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Document ID:
89DFEA01
Corrosion Control Considerations For M&R Stations
Author(s): John T. Kabay
Abstract/Introduction:
Most of the time people become engaged in controlling or preventing corrosion by appointment rather than as a final step in a process of formal education. The following basic information is designed to be helpful to that segment of such a group entering the Corrosion Control Field without the benefit of any extensive training in the basic sciences related to corrosion, but who may be called upon from time to time to take at least the first steps in anticipating or determining areas of active corrosion, either on their own or with fellow employees.
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Document ID:
D82FA1F3
How To Perform A Lost & Unaccounted-For Gas Program
Author(s): Rick Feldmann
Abstract/Introduction:
Many gas pipeline companies struggle with lost-andunaccounted- for-gas (L&U) and it can be a significant cost to their bottom as shown below. As shown in this inset, by reducing L&U from 6/10 percent to 1/4 percent, a typical company with a 2 Bcf daily throughput could achieve 10 million annually in bottom line benefits based on 4.00 gas prices.
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Document ID:
7E7D3A8C
Ground Free Surge Supression
Author(s): Greg Thomas Shumate
Abstract/Introduction:
The word Ground is so often used in the context of surge protection that it is difficult to imagine a surge protection device that does not require earth ground. Well, there are some applications where secondary-type surge protection devices do not require earth grounding. Eagle Research Corp. has developed a secondary surge protection system that has saved Mountaineer Gas and a number of other remote-mounted instrument users thousands of dollars in the last couple of years. This system is especially attractive for use with instruments mounted on cathodically protected piping and systems. Grounding cathodically protected equipment shorts out the protection and results in angry phone calls from the corrosion group.
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Document ID:
A8CC6A5C
Fundamentals & Development Of LNG Facilities
Author(s): John Jay Gamble, Jr.
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
C3E5F79D
Sampling And Conditioning Of Natural Gas Containing Entrained Liquid
Author(s): Donald P. Mayeaux
Abstract/Introduction:
The analysis of natural gas plays an important role in determining its monetary value. Natural gas is bought and sold based on its energy content and volume. The energy content or heating value is computed directly from the analysis. Physical constants of the gas, which are necessary to accurately determine its volume, are also computed from the analysis. Therefore the correct assessment of the monetary value of natural gas is dependant to a large extent on overall analytical accuracy. The largest source of analytical error in natural gas is distortion of the composition during sampling. Sampling clean, dry natural gas, which is well above its Hydrocarbon Dew Point (HCDP) temperature is a relatively simple task. However, sampling natural gas that is at or near its HCDP temperature is challenging. For these reasons, much attention has been focused on proper methods for sampling natural gas which have a high HCDP temperature. This presentation will address several problems associated with sampling natural gas which is at or near its HCDP temperature. Industry standards or guidelines for sampling natural gas will also be discussed.
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Document ID:
E46FAE52
Theory And Application Of The Gas Chromatograph
Author(s): Howard E. Brumbaugh
Abstract/Introduction:
Gas chromatography is a well-established method to obtain composition measurements in a gas or vaporized liquid/solid mixture. It physically separates, identifies, and quantifies mixture components in an injected sample. The laboratory gas chromatograph (GC), in use for many years, requires an operator to take a proper sample, fill a syringe, and inject the sample into the GC analyzer. It can perform many different types of analysis on a wide range of products. A lab technician can change out detectors, columns, and other parts to make the lab GC fit the specific application. Lab applications usually change more frequently than process applications. A process GC can be created by interfacing a GC with a microprocessor. It will automatically take, inject, and measure a sample.
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Document ID:
85450D81
Natural Gas Dehydration
Author(s): Matthew E. Vavro
Abstract/Introduction:
With increasingly stringent environmental concerns, dry bed desiccants are gaining rapid acceptance over traditional methods such as triethylene glycol. By properly selecting the correct desiccant, and operating the system in a way that is conducive to effective dehydration, costs can be kept to a minimum. Engineering support, coupled with adequate product choices, has dramatically reduced dehydration costs. Proper design of the entire system is probably the single largest cost saver. Historically, gas dehydration equipment has been non-integrated, with parts being purchased separately and assembled in the field, without considering how the plumbing, vessels, and desiccants work together. Our new approach offers an integrated system, where plumbing, gas flow, dryer design, and desiccant performance are all considered.
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Document ID:
F02C41D2
Indirect Heater Basic Technique And Practical Application
Author(s): Dwight Rhodes
Abstract/Introduction:
In the gas transmission, measurement and regulation industry, heaters are required for the safe and reliable distribution of natural gas. Indirect heating is the safest way to heat natural gas, ensuring that combustible gases are warmed by inert heat medium rather than direct contact with a flame-heated element.
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Document ID:
CDB2B4B6
Basic Electronics For Gas Measurement Technicians
Author(s): Tushar Shah
Abstract/Introduction:
At present, the use of electronics in gas measurement and control has become a necessity and a reality. In todays competitive environment, it is very important to measure, control and communicate gas related field parameters on time, accurately and reliably. The information may be used for marketing, operations/engineering, safety, or billing. As the gas industry moves gas from wellhead to burner tip, several types of electronic devices are used along the way for the gas measurement and control. Most of these devices utilize electronics to do their function. It is important for gas industry field service personnel to understand the basics of electronics to specify, purchase, operate and maintain these devices effectively.
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Document ID:
102470B9
Flow Measurement And Scada Technology
Author(s): Robert Findley, Bristol Babcock
Abstract/Introduction:
The communications revolution has accelerated in recent years, so it is no wonder advancements in measurement technology and SCADA systems have become standard conversation in the gas industry. Accurate, readily available flow data and control capabilities are critical to many gas production, transportation and storage companies. Data in the gas industry relates to profit and accountability to customers. The complexity of a remote flow computer, transmitter or process controller linked to the usability and data handling of a SCADA environment makes instantaneous information and historical retrieval a reality. Provided here is an overview of advancements in measurement and SCADA technology over the recent years. Each section tracks the historical progression of the major components of a SCADA environment.
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Document ID:
74A14D9D
Hybrid Lightning & Surge Protection For The Gas Pipeline Industry
Author(s): Donald R. Long
Abstract/Introduction:
The challenge facing the gas measurement and pipe line industry today is how to accurately compress, transfer, quantify, odorize, and deliver millions of cubic feet of gaseous hydrocarbons as reliably, efficiently and economically as possible. In order to accomplish this task, the industry increasingly relies on field instrumentation, much of it smart, connected via copper pathways to microprocessor based SCADA and PLC networks that form the backbone of the measurement and delivery control system. At the very same time, these control systems are highly vulnerable both in design and location to natures fury in the form of 200,000 ampere bolts of lightning! Is lightning a reality for a particular location? Where does it come from? How does it actually get into the control network? Is lightning the only form of surge to be concerned with? What devices can be used to prevent lightning and surge damage to both field instruments and I/O? Can proper grounding be the ultimate answer?
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Document ID:
60BDA4CC
Basic Electronic Communications For The Gas Industry
Author(s): Kenneth J. Pollock
Abstract/Introduction:
This paper introduces the common communications mediums used to convey intelligence for the gas industry. The gas industry requires fast and reliable communications for the conveyance of data for control and measurement applications. The data may be analog, digital, or even voice types of signals and may require transmission over a short distance of less than a couple of feet to over several hundred miles. As the gas is passed from the well head to the final user, many types of electronic devices are employed for fast and accurate measurement of the process. The link that is used to pass this information to the billing, control, or safety system is the communications system. Several communications circuits are required in order to convey the data and there is not any one perfect system that will meet the requirements in all situations.
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Document ID:
A5C7AE62
Efc Calibration: How Much Effort Is Required To Stay Accurate?
Author(s): David J. Firth
Abstract/Introduction:
Calibration is the process of aligning the performance of an instruments measurement with the performance of a known, traceable, measurement standard. Checking and maintaining calibration for an Electronic Flow Corrector (EFC) must be done periodically in order to document the accuracy of the device in custody transfer applications. An age-old measurement question is: How often do we need to calibrate devices in order to maintain accurate measurement? Recent additional questions are: Is this calibration schedule cost-effective? Can we calibrate less often and save money while providing accurate measurement? In recent years, corporate reorganizations and staff reductions have placed focus upon more efficient use of resources. New M&R management structures staffed by persons with experience in budgets, efficiency, and productivity have moved many of NiSource Energy Distributions EFCs to annual calibration schedules justi- fied by informal internal studies and EFC manufacturer recommendations. There is little worry within the firm that the move to longer calibration schedules jeopardizes good measurement. EFCs are stable devices with good calibration performance.
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Document ID:
B10021C0
Requirements Of An Egm Editor
Author(s): R. Michael Squyres
Abstract/Introduction:
The natural gas industry has adopted EGM as a means of increasing the speed and accuracy with which measurement information is obtained. This has created the need for an electronic data management system. These systems, if not properly designed and implemented, could potentially render the entire process useless. Therefore, it is essential that the system add functionality that complements the power of the hardware. With proper implementation, such a system will not only facilitate operations in todays fast paced, post-FERC 636 environment, but also will establish a foundation for meeting tomorrows measurement challenges. A good EGM data editing software package should provide a suite of tools to facilitate accurate and timely data processing. It should do this in a structured, feature rich, well designed environment. The program should include functions to do the following: import the data, recognize, review, and correct anomalies report, export, as well as provide advanced ad hoc query capabilities. Other considerations should include the developers commitment, resources, and long term strategy, vis--vis electronic gas measurement, as well as industrys overall acceptance of the package.
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Document ID:
6C8EFFD3
Principles Of Odorization
Author(s): John Rafferty
Abstract/Introduction:
Odorization injection and monitoring technology has advanced dramatically in the past 15 years. A former Chairperson of the Appalachian Short Course, Harold Englert of Columbia Gas Virginia, used to refer to odorization as, A little bit of science, and a whole lot of magic. The intent of this paper is to provide the reader with practical solutions to develop a solid odorization program, even in dense urban environments, in the hope of removing the, Magic, to a successful odorization program.
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Document ID:
3F127BC8
Gas Odorants: Health, Environment And Safe Handling
Author(s): Vicente Santa Cruz, David C. Miller
Abstract/Introduction:
Mercaptans are the most effective chemical substances for odorizing natural and liquid propane gas. Their extremely low odor threshold and powerful olfactory impact make them ideal warning agents. Mercaptans unique physical properties, including flammability, present unique challenges to personnel, communities, and emergency response services. In addition, mercaptans health and environmental concerns have prompted further studies and assessments to better understand how to protect the public and ensure that these materials are handled safely. This paper is an overview of current hazard information and recommended safe handling procedures as applicable to natural and liquid propane gas odorants.
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Document ID:
BCFD5B7E
Ultrasonic Gas Flow Meter Basics
Author(s): James W. Bowen
Abstract/Introduction:
This paper outlines the operating principal and application of ultrasonic gas flow metering for custody transfer. Basic principals and underlying equations are discussed, as are considerations for applying ultrasonic flow meter technology to station design, installation and operation. These applications are illustrated based on operating experience with the Instromet 3 path and 5-path Q.Sonic custody transfer flow meter, however, many of these issues may be generalized to devices manufactured by others
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Document ID:
423E933A
Basics Of Turbine Meters
Author(s): Paul G. Honchar
Abstract/Introduction:
Throughout the world, gas measurement utilizes two basic principles to measure gas volumes, positive displacement and inferential meters. Positive displacement meters comprise the large majority of measurement devices in use while inferential meters are used primarily for large volume measurement and thus fewer applications.
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Document ID:
D33556D4
Orifice Meter Basics
Author(s): Kevin Finnan
Abstract/Introduction:
This class is going to be faithful to the title and focus on basics of orifice meters. It is intended as an introduction to any gas company employees who are interested in gaining a working knowledge of orifice meters, including where they are used and why. We will also briefly discuss the orifice meter from an operation and maintenance point-of-view. For field technicians and anyone else, who will be directly involved with orifice meter operations and maintenance, this class is an introduction and will give you an understanding of the basic concepts. However, it is not a replacement for your companys operating procedures but is, rather, a supplement to them. No prerequisites are assumed, just a genuine interest in the topic.
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Document ID:
559394EE
Basic Principles Of Pilot Operated Flexible Element Regulators
Author(s): Michael Garvey
Abstract/Introduction:
Pilot Operated Flexible Element Regulators are capable of providing very accurate control in natural gas transmission and distribution pipelines. The Pilot Operated Regulator provides advantages over both self-operated regulators and control valves. Primary benefits include simplicity of operation and elimination of any fugitive emissions caused by atmospheric bleed gas. However, it is important to recognize the limitations of the pilot operated flexible element regulator and apply it accordingly. The original Flexible Element Regulator, the Flexflo, was developed by the Grove Valve and Regulator Company circa World War II. The original intent for the regulator was to regulate water in submarine ballasting systems. However, Grove quickly recognized that the Flexflo regulator product was ideally suited for pressure control applications in natural gas pipelines. Many advances have been made since the original Flexible Element was created more then fifty years ago, but the same basic operational advantages and principles of operation remain unchanged.
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Document ID:
7C3E1337
Self-Operated Regulator Basics
Author(s): Trent Decker
Abstract/Introduction:
Gas pressure regulators have become very familiar items over the years, and nearly everyone has grown accustomed to seeing them in factories, public buildings, by the roadside and even in their own homes. As is frequently the case with many such familiar items, we all have a tendency to take them for granted. Its only when a problem develops or when we are selecting a regulator for a new application that we need to look more deeply into the fundamental of the regulators operation.
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Document ID:
3F659DD5
Basic Pressure And Flow Control
Author(s): Paul R. Sekinger
Abstract/Introduction:
The natural gas industry utilizes two devices to reduce gas pressure and control gas flow. The first is the regulator and the second is a control valve. The control valve is utilized for high volumes and it can perform flow control as will as pressure control. This paper will provide the fundamentals of control valve types, sizes, and the controllers that are utilized to operate the control valves. We will also investigate the differences between the regulator and the control valve and the advantages and disadvantages of each.
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Document ID:
F18302E8
Basics Of Diaphragm Meters
Author(s): Jerry Kamalieh
Abstract/Introduction:
The first gas company in the United States, The Gas Light Company of Baltimore, Maryland, founded in 1816, struggled for years with financial and technical problems while operating on a flat-rate basis. Its growth was slow, its charge for gas service beyond the pocketbook of the majority. By comparison, the New York Gas Light Company founded in 1823 prospered and expanded. They had built their system on the use of gas meters to measure the supply of gas to customers, and a large one to register the quantity made at the station before it is conveyed to the gasometers. The pattern of operation used by this New York company was quickly copied by other companies throughout the east coast, including the Baltimore company. Seeing the success in New York, businessmen formed new gas companies in Albany, Boston, Philadelphia, New York, etc., and the new industry in the United States began to flourish.
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Document ID:
6AA326D8
Diaphragm Meters Applications, Installations And Maintenance
Author(s): Paul G. Honchar
Abstract/Introduction:
The fundamental design concept and operating principle of current diaphragm meters has been around for over 160 years. Through the years there have been significant improvements in materials, assembly and calibration, but the basic operating principle has weathered time. Its dif- ficult to displace a technology that fits the intended use extremely well, lasts 25+ years, and is very economically affordable. This presentation will review and highlight some of the reasons why this technology has survived the test of time for so long.
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Document ID:
05EFCCC7