Measurement Library

North Sea Flow Measurement Workshop Publications (2008)

The Importance Of Discerning The Impact Of New Measurement Technology
Author(s): David J. Fish
Abstract/Introduction:
With the current demand for improved technologies in the area of fluid 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. The LNG market has impacted the operations of the typical gas supply systems worldwide. The demand for more and more crude oil has put pressure on old measurement designs to become increasingly flexible to a variety of crude oil deliveries. Designing and creating improved products for the measurement of volume and quality has provided new challenges as the marketing and transportation of oil and natural gas has changed. This paper will focus on the natural gas sector, however, the lessons can be transferred to the entire industry.
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Document ID: 66F01B17

V-Cone Wet Gas Metering
Author(s): Richard Steven
Abstract/Introduction:
Single phase differential pressure (DP) meters can be used to meter wet gas flows if the liquid flow rate can be obtained from an independent source and a suitable wet gas correction factor is available. As it is not a trivial task to measure the liquid flow rate of a wet gas flow, sophisticated wet gas flow meters have been developed that meter the gas and liquid phases simultaneously. The complexity of most wet gas meters means that they tend to be expensive (relative to standard gas meters). Therefore, due to economic necessity, many wet gas flow applications still have single phase gas meters being fitted to meter wet gas flows. This situation is not ideal, as it means poorer metering performance than what is really desired.
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Document ID: 2FEDB4B5

Pressure And Temperature Effects For Ormem Lange Ultrasonic Gas Flow Meters
Author(s): Per Lunde, Kjell-Eivind Frysa, Trond Folkestad
Abstract/Introduction:
Ultrasonic gas flow meters (USMs) may be influenced by pressure and temperature in several ways. Change of the meter bodys cross-sectional area (the pipe bore) influences directly on the amount of gas flowing through the meter. Change of the ultrasonic path geometry (i.e. change of the inclination angles and lateral chord positions, caused by e.g. meter body diameter change and change of the orientation of the ultrasonic transducer ports) influences on the transit times and the numerical integration method of the meter. Change of the Reynolds number influences on the integration method. Change of the length of the ultrasonic transducer ports influences on the acoustic path lengths, and thus on the transit times. Likewise, change of the length of the ultrasonic transducers influences on the acoustic path lengths, and thus on the transit times. In addition, changes of the transducer properties such as the directivity, influences on the diffraction correction, and thus on the transit times.
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Document ID: 290656A2

Impact Of Regulator Noise On Ultrsonic Flow Meters In Natural Gas
Author(s): Idriz Krajcin, Martin Uhrig, Andrew Wrath, Toralf Dietz, Volker Herrmann
Abstract/Introduction:
The impact of pressure regulator noise on the performance of ultrasonic meters has been discussed for several years now. This is one of the problems still to be solved in ultrasonic flow metering technology. Engineers have so far attempted to solve the problem by installing complex spatial pipe arrangements at high costs to reduce interfering noise levels. The issue has been examined systematically both in field tests in the measuring station of a transportation pipeline and on the E.ON Ruhrgas high-pressure test facility in Lintorf to determine the limits of use and potential applications of an ultrasonic gas meter with chordal path layout in combination with a regulator. The tests made on a 16-inch meter in the measuring station confirmed that proper functioning of the meter with respect to pressure differential and flow rate can be guaranteed even under the most extreme conditions.
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Document ID: C2583697

Euroloop: Metrological Concepts For Efficient Calibrations And Primary Realization Of Accurate Reference Values In Flow
Author(s): Mijndert P. Van Der Beek
Abstract/Introduction:
In a previous introductory paper 1, the ranges, possibilities and operation practice of the new calibration facilities for Natural Gas and several Oil products in Europe, are depicted. The stringent claim on CMC or Calibration and Measurement Capability is the driving force for criteria set for process stability, day-to-day reproducibility, long-term behavior of working standards and finally accuracy of the international linked reference value at the position of the device under test. The superb CMC claims imply highest demands in innovative designing. This paper focuses on a metrological engineering concept in which via an iterative process a balance is found between: optimal piping configuration, smallest uncertainties, sustainable traceability maintenance at one side and effective operation, lowest operational and capital expenses on the other. The International traceability of the Hydro Carbon calibration facility (HyCal) will be realized by unique piston provers covering a range up to 5000 m3/h. Theoretic and empirical correction methods will be avoided and most sensitive parameters will be determined on the spot to increase credibility of estimated uncertainty sources. For instance, e.g. seal leakage, line-pack effects, diameter change will be measured and processed. International acceptability of these rather small uncertainties will increase when uncertainty estimations are supported by on scale demonstration of auxiliary instrument performance therefore a significant set of tests is scheduled in the near future. The design of the intelligent piston will be shown as well as simulations of the piston behavior related to pump performance, inertias, control characteristics of valves etc. The primary realization will be intrinsic in the piston prover itself and changes of the reference volumes due to pressure, temperature and oil movement will be measured on line. Traceability of the HP Gas Calibration laboratory will be based upon a Gas Oil Piston Prover and the Dutch-German-French Harmonized Reference Value. The prover was built in 2001 together with a multiplier and carrier of reference values, embodying the new traceability chain. The paper also focuses on the methods and steps to validate and certify such large Natural Gas calibration loop. In due coarse, the public will be informed regularly through series publications.
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Document ID: 400B3889

Uncertainty Modelling For Instruments, Systems & Plants - An Essential Guide To Optimising Performance
Author(s): Michael Mackay, Justin Walter
Abstract/Introduction:
Knowledge of the uncertainty of Custody Transfer and Allocation measurement is typically calculated following the published Guidelines & Standards using Manufactures Data. But what if there are environmental issues regarding the Installation or Type of Equipment. This Paper identifies and illustrates ways of using established uncertainty theory as a tool for modelling the design of measurement equipment, the combination of that equipment into flow measurement systems and/or the modelling of complex Plants/Allocation Systems. By using these tools measurement exposure can be expressed in terms of uncertainty, units measured or financial risk, thereby giving an insight into the advantages of one method of measurement over another. In a similar way Design Houses can determine the optimum solution for a measurement system and Operators the most cost effective solution for Plant/Allocation metering.
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Document ID: ECFAF8FB

Erosion In A Venturi Meter With Laminar And Turbulent Flow And Low Reynolds Number Discharge Coefficient Measurements
Author(s): Gordon Stobie, Robert Hart, Steve Svedeman, Klaus Zanker
Abstract/Introduction:
Venturi meters are commonly used in single and multiphase flows. The ISO standard (ISO 5167-4) provides meter discharge coefficients for Venturi meters in turbulent flows with Reynolds numbers above 2 x 105. In viscous fluids, Venturi are sometimes operated in laminar flows at Reynolds numbers below the range covered by the standards. Venturi meters may also be subjected to erosion from sand entrained in the fluid. The effects of erosion on the Venturi meter performance is a concern for long-term field operations. Test data were obtained on a classical Venturi meter operating in laminar flow to measure the discharge coefficient as a function of Reynolds number. Data were obtained over a range of flow rates and fluid viscosities. Modeling using computational fluid dynamics (CFD) was used to obtain additional insight into the Venturi meter performance in laminar flow conditions. The test setup and test results are presented, with the CFD modeling results. Tests were also conducted to evaluate the effects of erosion on Venturi meters. Three Venturi meters were exposed to oil/sand and water/sand slurry erosion. The meters were flow tested before and after exposure to the slurry flows to measure changes in the meter discharge coefficients. Dimensional changes were also recorded.
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Document ID: 082EE577

Traceable Calibration Of Liquid Densitometers
Author(s): Norman Glen
Abstract/Introduction:
Density measurement is a key element of both mass and volume flowrate measurement in the oil industry and as such is fundamental to the commercial operation of facilities. The most widely implemented approach for mass flow measurement is to use a volumetric flowmeter and a densitometer. All flowmeters require periodic calibration and traceability within the UK is provided through the Flow Programme. All commercial densitometers also require periodic calibration. In 2004 the Aberdeenbased Energy Resources Development Unit of DTIs Energy Group identified a need for research into practical methods for in-situ calibration of densitometers, as well as a greater understanding of the effects on densitometer performance of variations in product density, pressure and temperature. This is particularly important as more and more operators are involved in smaller field developments tied back to other operators platforms, feeding third-party pipeline infrastructures. In addition, as more HTHP fields come on stream, more densitometers will be operating at temperatures and pressures significantly different from those currently used as the reference conditions for calibration. TUV NEL, the custodians of the UK Fluid Density Standards, are leading a Joint Industry Project (JIP) aimed at providing the oil and gas industry with confidence in densitometer performance, by developing a calibration procedure which links traceably to National Standards. Fourteen operators, a densitometer manufacturer and the UK oil and gas regulator (part of the Department for Business, Enterprise and Regulatory Reform) have joined the project.
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Document ID: 604888D2

A New Approach To Mpfm Performance Assessment In Heavy Oil
Author(s): Martin Basil, Gordon Stobie, Winsor Letton
Abstract/Introduction:
The performance of a MPFM (Multi Phase Flow Meter) is normally assessed with an observational data model obtained by comparison with a reference meter. Typically the vendor will provide the performance from their own databases using data from a wide range of sources including JIPs, client sponsored trials, field trials and the vendors own calibration facilities. This data is processed to model the MPFM and compiled into databases over a long period of time at considerable cost. Understandably the vendor regards this data as proprietary and seeks to control access by releasing only limited subsets specific to an application. In the early stages of a project, fluid properties and flow rates may not be well understood requiring repeated requests to the vendor for performance data which can be very time consuming. This reliance on vendor data that is not transparent does little to instil confidence in users who will often conduct costly independent trials to verify the suitability of the selected MPFM, or may revert to more conventional methods of measurement.
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Document ID: FBE6A0BB

LNG Allocation Metering Using 8-PATH Ultrasonic Meters
Author(s): Gregor Brown, Herb Estrada, Don Augenstein, Terry Cousins
Abstract/Introduction:
This paper discusses the requirements and challenges of in-line allocation metering of LNG in facilities with common storage and shared offloading. Field trials conducted at an LNG test site are described and the results and conclusions of these tests are summarised. The design of the Caldon ultrasonic meter for LNG is discussed, with particular reference to the requirements for application at cryogenic temperatures and very high Reynolds numbers. The benefits of using an 8-path transducer arrangement to ensure transfer of calibration from the lab to the field are demonstrated, both analytically and with reference to the field test data.
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Document ID: 808216F1

An Ultrasonic Flowmeter For Custody Transfer Measurement Of LNG: A Challenge For Design And Calibration
Author(s): Jankees Hogendoorn, Andre Boer, Helen Danen
Abstract/Introduction:
For the transport of natural gas, liquefying gas is becoming popular compared to for example transporting gas over large distance pipelines. Transport of gas is receiving much attention worldwide as for example gas is increasingly being found in remote areas and importing countries are looking for ways to diversify the resources of their gas supplies. Another trend is the increasing number of parties involved in the LNG market place. In addition, the costs of the liquefaction and re-gasification of gas and the transport of LNG are decreasing. An increase in the trade of LNG also means an increase in the custody transfer and fiscal metering points for gas in cryogenic conditions. Tank gauging has been a popular measurement method for LNG, but it has its limitations and increased demand for very accurate flow measurements can be observed.
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Document ID: E0D325C7

Flare Metering With Optics From Blue-Sky Technology To The Real World
Author(s): Jody Parker, Gordon Stobie, Ivan Melnyk,Chip Letton
Abstract/Introduction:
During a presentation at the 2006 North Sea Flow Measurement Workshop on new and current flare metering technologies, infrared and other optical methods of gas flow measurement were referred to as blue-sky technology. The inference was that these technologies, whilst they might have merit, probably would not be available for some time, if ever. In reality, this is far from true, as at least one vendor of such devices has developed its technology to the point that laboratory and field testing have been carried out, and more than twenty-five units have been sold and installed into operational plants. The purpose of this paper is to review the development, testing and deployment of the Photon Control Optical Flow Meter. In particular, the following topics will be addressed: 1. Overview of the technology, its various embodiments, its advantages and shortcomings, with a synopsis of a Canadian JIP under which development was carried out. 2. Presentation of results: Flow Laboratory testing for installation effects A variety of general Canadian onshore retrofit installations Specific examples from the eight ConocoPhillips Canada Real World installations An example using optical flare metering technology in Statoil 3. Detailed conclusions on the JIP, the gradual implementation of the new technology into the industry, with feedback from both users and regulators on being able to manage flare gas discharges.
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Document ID: E4E6AF4B

Uncertainty Analysis Of Emissions From The Statoil Mongstad Oil Refinery
Author(s): Kjell-Eivind Frysa, Anne Lise Hopland Vagenes, Bernhard Srli, Helge Jrgenvik
Abstract/Introduction:
In new European and national legislations, there is increased focus on the reporting of the emmissions related to greenhouse gases from process plants. This includes reporting and documentation of uncertainty in the reported emmissions, in addition to specific uncertainty limits depending on the type of emission and type of measurement regime. In a process plant like the Statoil Mongstad oil raffinery, there may be a huge number of measurement points for mass flow. These measured mass flow rates have to be added in order to obtain the total emission for a given source. Typically, orifice plates are used at many of the measurement points. These orifice plate meters are ususally not equipped with individual densitometers. In stead, they are pressure and temperature corrected from a common upstream densitometer. This will give correllations between the individual flow meters.
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Document ID: C8F95608

Measurement Of Produced Water Discharges - Regulatory Requirements And Recent Progress
Author(s): Alick Macgillivray, Ming Yang, Richard Paton
Abstract/Introduction:
Until recently, produced water was considered to be a waste stream for which metering was not a critical issue. As a result, little attention had been paid to the subject of metering this stream. However, in 2001 OSPAR (Oslo - Paris Commission) recommended a 15% reduction of oil discharged via produced water by 2006 1, in relation to the year 2000. This meant that there was a need to accurately measure both the concentration of oil in produced water and the volume of water being discharged. In the UK, new Regulations, called OPPC (Offshore Pollution Prevention and Control) 2 were introduced in 2005, which require the measurement of produced water volume to an uncertainty of 10% 3.
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Document ID: 204CFAC7

The Relevance Of Two Different Path Layouts For Diagnostic Purposesin One Ultrasonic Meter
Author(s): John Lansing, Volker Herrmann, Toralf Dietz
Abstract/Introduction:
During the past several years the use of ultrasonic meters (USMs) has gained world-wide acceptance for fiscal applications. The many benefits of USMs have been documented in several papers at virtually every major conference. As the cost of gas continues to increase, the importance of knowing that the ultrasonic meter is operating accurately has never been more important. The use of diagnostics to help identify metering issues has been discussed in several papers over the past few years Ref 1 & 2. The traditional method of verifying whether the USM is operating accurately essentially requires using the USMs diagnostic information to help understand the meters health. This has often been referred to as Conditioned Based Maintenance, or CBM for short. Different USM meter designs require different analysis techniques, especially for the velocity profile analysis. For the field technician, it is often difficult to understand all the diagnostic features of each USM meter design. Through the years software has been developed to help determine if the meter is operating correctly or not. However, it is still very difficult to clearly define limits on some of the diagnostic parameters that translate into a quantifiable metering error.
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Document ID: 5E9A9E7C

Test Of A 1 Inch Roxar Watercut Meter On Light Condensate With Very Low Water Content.
Author(s): Georg Johnsen, Rune Martinussen
Abstract/Introduction:
The Oil industry is rapidly moving towards more difficult crude products, as more and more of the easy produce able crude oil will be finished. This leads to new challenges for the whole industry, finding better equipment to coupe with these challenges. One such trend is in the oil business is moving towards lighter oils or condensates. These will have to be processed and transported under high pressure, to stay liquid. The residue water, more or less saline, in condensates can cause serious corrosion problems in the downstream process equipment and pipelines. The Roxar Watercut meter have undergone a test on light condensate, with standard density of about 625 kg/m3, to establish how good the meter is for measuring the very low water content in such products. The ordinary process conditions were 0-650 ppm volume water, while the maximum range was 0-1650 ppm. The test took place offshore on a real condensate line, and was conducted by a large oil company.
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Document ID: 0E4296D1

The Importance Of Discerning The Impact Of New Measurement Technology
Author(s): David J. Fish
Abstract/Introduction:
With the current demand for improved technologies in the area of fluid 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. The LNG market has impacted the operations of the typical gas supply systems worldwide. The demand for more and more crude oil has put pressure on old measurement designs to become increasingly flexible to a variety of crude oil deliveries. Designing and creating improved products for the measurement of volume and quality has provided new challenges as the marketing and transportation of oil and natural gas has changed. This paper will focus on the natural gas sector, however, the lessons can be transferred to the entire industry.
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Document ID: A45B5C59

A Method For Remote In-Line Calibration Of Water Fraction Meters
Author(s): Dag Flolo
Abstract/Introduction:
A new method has been developed which is suitable for remote in-line calibration of water fraction meters. The method utilizes settling of water in a vertical line under no-flow conditions. As water is allowed to settle in a hydrocarbon liquid, a repeatable, low amount of water will remain solved in the hydrocarbon liquid. The amount of water can be determined, and the water in oil meter can be zero-point calibrated at this point. The method is suitable for installations where water cut meters are installed in a vertical pipe section and where no flow conditions can be provided manually or happens in occasional shut downs without depressurization. Current methods for calibration require entering a well-defined test fluid or air into the meter and/or that representative samples are taken and analyzed in a laboratory. This is especially challenging with unstable hydrocarbon liquid or low-density condensates. Current methods also require the presence of competent personnel at the site.
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Document ID: 42A07437

Calibration And Verification Of Multiphase Meters For Allocation Metering Of The Urd Field
Author(s): Knut Skardalsmo, Erik Aabro
Abstract/Introduction:
This paper presents the history and current status of multiphase metering of the production from the five sub sea wells of the Urd field. The Urd field is a satellite field to the Norne FPSO and the Urd stream is processed onboard Norne. The production from the Urd field was started in November 2005. The Urd field consists of two sub sea templates, Svale and Str, and the distance to the Norne FPSO is respectively nine and five kilometres. Each of the five production wells is equipped with a multiphase meter and the total Urd stream is measured in a topside multiphase meter at Norne. Furthermore it is possible to route the Urd stream through a test separator with state of the art metering equipment. The oil from the Svale skid has high density and viscosity whereas the oil from the Str is lighter and quite similar to the oil from the Norne field.
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Document ID: 31F5286D

Fluid Composition Analysis By Multiple Gamma-Ray Beam And Modality Measurements
Author(s): Geir Anton Johansen, Stein-Arild Tjugum
Abstract/Introduction:
The feasibility of using multiple gamma-ray beams to identify the type of flow regime has been demonstrated. One gamma-source with principal emission at 60 keV is used because this relatively low energy enables efficient collimation and thereby shaping of the beams, as well as compact detectors. One detector is placed diametrically opposite the source whereas the second and eventually the third are positioned to the sides so that these beams are close to the pipe wall. The principle is then straight forward to compare the measured intensities of these detectors through that identify the instantaneous cross sectional gas-liquid distribution. By counting the intensity short time slots and ( 100 ms), rapid regime variations are revealed. Varying water salinity is another challenge for most multiphase flow meters because it affects volume fraction calculations based on gamma-ray, electrical conductance and other measurements. There have been a few approaches to solve this without relaying on off line calibration. One of these utilizes the difference in the composition of the gamma-ray attenuation coefficient at different energies. The method presented here take advantage of the same effect, but though simultaneous measurements of transmitted and scattered gamma-rays from a 241-Am source. It has been shown that the gas volume fraction then can be determined independent of changes in the water salinity. Once again the challenge is to minimize the effects of changes in the flow regime.
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Document ID: B935BED7

Wet Gas Metering Using Sonar-Based Flow Meters And Piping Pressure Loss Gradients
Author(s): Daniel L. Gysling, Douglas H. Loose, Nicolas Morlino, Alex Van Der Spek
Abstract/Introduction:
Convenient and accurate measurement of gas and liquid rates of wet gas mixtures represents a long standing challenge within the oil and gas industry. Recently, sonar-based flow meters have been demonstrated to provide accurate measurement of the mixture flow rate of wet gas mixtures on a clamp-on basis. This paper describes an approach which combines sonar-based flow meters with the measured pressure drop across a section of pipe to provide gas and liquid flow rates. The approach leverages recognition that variations in the pressure gradient along a given section of pipe containing a wet gas mixture are primarily determined by the flow rate and liquid content of the mixture. In this approach, a sonar-based flow meter provides the mixture flow rate, and the measured pressure drop across a section of fixed geometry piping provides a basis to determine the liquid loading. The interpretation of the measured quantities in terms of gas and liquid flow rates is performed using either empirical data-based model or with the assistance of a multiphase flow model. The approach is of particular interest in applications in which pressure gradient measurements either exist, or can be installed without requiring a process shutdown. Two data sets are provided demonstrating the utility of this approach: 1) a laboratory test with data spanning range of flow rates and pressures with wetness levels predominately in range of 0 to 2.0 Liquid Gas Mass Ratio, and 2) a field test in which the measured produced gas and liquid rates from a wet gas well are compared to test separator measurement over a range of flow rates and wetnesses ranging from 0.08 to 0.15 Liquid to Gas Mass Ratio.
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Document ID: 2C2EE189

A Prototype Wet-Gas And Multiphase Flowmeter
Author(s): E. S. Johansen, A. R. W. Hall, . H. nalmis, D. J. Rodriguez, A. Vera, V. Ramakrishnan
Abstract/Introduction:
A wet-gas flowmeter based on the field-proven downhole fiber-optic multiphase flowmeter has been developed. The flowmeter is based on an extended throat Venturi-nozzle and a Sonar flowmeter. This combination exploits the characteristics of these two devices in wet-gas flows. For the Venturi, there is a well-defined and large over-reading with increasing liquid-loading, whereas this has a significantly lower impact on the total flow rate measured by Sonar. The Sonar-Venturi wet-gas flowmeter has been in development over the past several years and has been tested extensively in industry flow loops. Particular emphasis has been placed on developing a flowmeter with a broad operating envelope that includes a large span of fluid properties, a high turndown ratio, and well characterized response both within and outside its intended operating envelope. The wet-gas performance has been demonstrated at the recently commissioned CEESI 3 phase wet-gas flow loop, yielding total and gas flow rates better than 5%,* liquid flow rate better than 0.5 m3/hr in Type I wet gas,1 and better than 20% in Type II wet gas. A Red Eye 2G nearinfrared (NIR) water cut meter is used to differentiate the oil/condensate and water. The Red Eye 2G has field proven performance in low gas volume fraction (GVF) flows for full range of water cut. A prototype version has demonstrated 5% water cut uncertainty in high GVF multiphase2 flows and initial testing of the Red Eye in wet-gas flows is showing great promise.
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Document ID: 523177F4

A Discussion On Wet Gas Flow Parameter Definitions
Author(s): Andrew Hall, Douglas Griffin, Richard Steven
Abstract/Introduction:
For more than a decade, the technical papers presented at flow meter conferences have included papers that have discussed the issues of wet gas flow metering. This is directly related to the continued increase in the development and use of wet gas flow in the natural gas production industry. Wet gas meter technologies had previously been developed primarily for steam measurement within the power generation industry. However, the steam industrys research into this topic had wound down by the early 1980s. When the natural gas production industry restarted this research on the strength of earlier publications, some terminology was taken from these records and other terminology was created by the new research. However, there has never been any attempt to unify the terminology. Therefore, the result is that researchers, meter manufacturers and meter users are free to produce their own definitions for commonly used terms, which often do not match those of others, and as a result of this there has been confusion and misunderstanding.
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Document ID: F35954BC

Wet Gas Performance Of Differential Pressure Flowmeters
Author(s): Russell Evans
Abstract/Introduction:
Wet gas flow measurement is becoming vital to the production of natural gas. New wells with marginal outputs cannot justify gas-liquid separation equipment and must transfer gas which contains some liquid volume. The flow measurement device on each well dictates the allocation earnings and must therefore provide gas flow measurement as accurately as possible. Several types of differential pressure based flowmeters are currently being used in wet gas flow measurement. Differential pressure based flowmeters share many performance characteristics in wet gas applications. However, studies have also found that there can be significant differences in the correlations between meter over-reading and liquid content depending on the type of differential pressure meter being tested.
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Document ID: FA3CE8BB

Uncertainty Modelling For Instruments, Systems & Plants - An Essential Guide To Optimising Performance
Author(s): Michael Mackay, Justin Walter
Abstract/Introduction:
Knowledge of the uncertainty of Custody Transfer and Allocation measurement is typically calculated following the published Guidelines & Standards using Manufactures Data. But what if there are environmental issues regarding the Installation or Type of Equipment. This Paper identifies and illustrates ways of using established uncertainty theory as a tool for modelling the design of measurement equipment, the combination of that equipment into flow measurement systems and/or the modelling of complex Plants/Allocation Systems. By using these tools measurement exposure can be expressed in terms of uncertainty, units measured or financial risk, thereby giving an insight into the advantages of one method of measurement over another. In a similar way Design Houses can determine the optimum solution for a measurement system and Operators the most cost effective solution for Plant/Allocation metering.
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Document ID: 61677BCE


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