1、BSI Standards PublicationBS ISO 10790:2015Measurement of fluid flow inclosed conduits Guidanceto the selection, installationand use of Coriolis flowmeters(mass flow, density and volumeflow measurements)BS ISO 10790:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation
2、of ISO 10790:2015. Itsupersedes BS ISO 10790:1999 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CPI/30/5, Velocity and Mass Methods.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does
3、not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 78002 8ICS 17.120.10Compliance with a British Standard cannot confer immunity fromlegal obl
4、igations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 April 2015.Amendments issued since publicationDate Text affectedBS ISO 10790:2015 ISO 2015Measurement of fluid flow in closed conduits Guidance to the selection, installation and use
5、of Coriolis flowmeters (mass flow, density and volume flow measurements)Mesure de dbit des fluides dans les conduites fermes Lignes directrices pour la slection, linstallation et lutilisation des mesureurs effet Coriolis (mesurages de dbit-masse, masse volumique et dbit-volume)INTERNATIONAL STANDARD
6、ISO10790Third edition2015-04-01Reference numberISO 10790:2015(E)BS ISO 10790:2015ISO 10790:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by
7、 any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211
8、Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 10790:2015ISO 10790:2015(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 13.1 Definitions specific to this Coriolis flowmeter standard 13.2
9、 Definitions from VIM, ISO/IEC Guide 99 (JCGM:2012) 33.3 Symbols . 43.4 Abbrevations . 54 Coriolis flowmeter selection criteria 54.1 General . 54.2 Physical installation 54.2.1 General 54.2.2 Installation criteria 64.2.3 Full-pipe requirement for liquids 64.2.4 Orientation 64.2.5 Flow conditions and
10、 straight length requirements . 64.2.6 Valves . 64.2.7 Cleaning . 64.2.8 Hydraulic and mechanical vibrations 74.2.9 Pipe stress and torsion . 74.2.10 Crosstalk between sensors . 74.3 Effects due to process conditions and fluid properties 74.3.1 General 74.3.2 Application and fluid properties 74.3.3
11、Multiphase flow 84.3.4 Influence of process fluid . 84.3.5 Temperature effects 84.3.6 Pressure effects . 94.3.7 Pulsating flow effects . 94.3.8 Viscosity effects 94.3.9 Flashing and/or cavitation 94.4 Pressure loss . 94.5 Safety . 94.5.1 General 94.5.2 Hydrostatic pressure test . 94.5.3 Mechanical s
12、tress .104.5.4 Erosion. 104.5.5 Corrosion . 104.5.6 Housing design .104.5.7 Cleaning 104.6 Transmitter (secondary device) . 104.7 Diagnostics 115 Inspection and compliance .116 Mass flow measurement 126.1 Apparatus . 126.1.1 Principle of operation .126.1.2 Coriolis sensor 146.1.3 Coriolis transmitte
13、r 156.2 Mass flow measurement 156.3 Factors affecting mass flow measurement. 176.3.1 Density and viscosity 17 ISO 2015 All rights reserved iiiContents PageBS ISO 10790:2015ISO 10790:2015(E)6.3.2 Multiphase flow .176.3.3 Temperature . 186.3.4 Pressure 186.3.5 Installation . 186.4 Zero adjustment 186.
14、5 Calibration of mass flow measurement 187 Density measurement 197.1 General 197.2 Principle of operation 207.3 Specific gravity of fluids . 217.4 Density measurement uncertainty . 217.5 Factors affecting density measurement . 217.5.1 Temperature . 217.5.2 Pressure 227.5.3 Multiphase (Two phase). 22
15、7.5.4 Flow effect 227.5.5 Corrosion and erosion 227.5.6 Coatings 227.5.7 Installation . 227.6 Density calibration and adjustment 227.6.1 General. 227.6.2 Manufacturers density calibration . 227.6.3 Field density calibration and adjustment238 Volume flow measurement at metering conditions 238.1 Gener
16、al 238.2 Volume calculation . 238.3 Gas as a process fluid 248.4 Volume measurement uncertainty . 248.5 Special influences 248.5.1 General. 248.5.2 Empty pipe effect 248.5.3 Multiphase fluids 248.6 Factory calibration 248.6.1 Mass flow and density 248.7 Volume check . 25Annex A (informative) Calibra
17、tion techniques .26Annex B (informative) Safety guidelines for the selection of Coriolis flowmeters 29Annex C (informative) Considerations for multi-component liquid systems .31Annex D (informative) Miscible liquids containing chemically non-interacting components 34Bibliography .37iv ISO 2015 All r
18、ights reservedBS ISO 10790:2015ISO 10790:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each me
19、mber body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International E
20、lectrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different type
21、s of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be h
22、eld responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is informati
23、on given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the f
24、ollowing URL: Foreword Supplementary information .The committee responsible for this document is ISO/TC 30, Measurement of fluid flow in closed conduits, Subcommittee SC 5, Velocity and mass methods.This third edition cancels and replaces the second edition (ISO 10790:1999), which has been technical
25、ly revised. It also incorporates the Amendment ISO 10790:1999/Amd 1:2003. ISO 2015 All rights reserved vBS ISO 10790:2015ISO 10790:2015(E)IntroductionThis International Standard has been prepared as a guide for those concerned with the selection, testing, inspection, operation, and calibration of Co
26、riolis flowmeters (Coriolis flowmeter assemblies). A list of related International Standards is in the Bibliography.This International Standard provides the following:a) description of the Coriolis operating principle;b) guideline to expected performance characteristics of Coriolis flowmeters;c) des
27、cription of calibration, verification, and checking procedures;d) description of potential error sources;e) common set of terminology, symbols, definitions, and specifications.The next paragraphs contain an explanation of when to use the measurement terminology, uncertainty, and accuracy.The VIM def
28、inition (see 3.2) of accuracy: closeness of agreement between a measured quantity value and a “true quantity value” of a measurand. Per the VIM, accuracy is a quality and should not be given a numerical value.To understand the preceding paragraph, one needs to understand that a “true quantity value”
29、 does not exist. The best that can be done is to determine the measured quantity value with measurement instrumentation calibrated with a very good but imperfect reference. Therefore, the measurement is an estimate. Uncertainty is used to define these measurement estimates (see 3.2.2).Many Coriolis
30、manufacturers use accuracy and zero stability as part of their published performance specifications. The manufacturers accuracy specification includes repeatability, hysteresis, and linearity but can also include other items that might be different for each manufacturer.This International Standard w
31、ill use uncertainty to quantify the results of a flow measurement system. This International Standard will only use accuracy when it is very clear that it is referring to or using all or part of the manufacturers published specifications.vi ISO 2015 All rights reservedBS ISO 10790:2015Measurement of
32、 fluid flow in closed conduits Guidance to the selection, installation and use of Coriolis flowmeters (mass flow, density and volume flow measurements)1 ScopeThis International Standard gives guidelines for the selection, installation, calibration, performance, and operation of Coriolis flowmeters f
33、or the measurement of mass flow and density. This International Standard also gives appropriate considerations regarding the type of fluids measured, as well as guidance in the determination of volume flow and other related fluid parameters.NOTE Fluids defined as air, natural gas, water, oil, LPG, L
34、NG, manufactured gases, mixtures, slurries, etc.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition
35、of the referenced document (including any amendments) applies.ISO 5168, Measurement of fluid flow Procedures for the evaluation of uncertaintiesISO/IEC 17025, General requirements for the competence of testing and calibration laboratoriesISO/IEC Guide 99:2007 (JCGM 200:2012), International vocabular
36、y of metrology Basic and general concepts and associated terms (VIM)3 Terms and definitions3.1 Definitions specific to this Coriolis flowmeter standardFor the purposes of this document, the following terms and definitions apply.3.1.1Coriolis flowmeterdevice consisting of a flow sensor (primary devic
37、e) and a transmitter (secondary device) which measures mass flow and density by means of the interaction between a flowing fluid and the oscillation of a tube or tubesNote 1 to entry: This can also provide measurement of the tube(s) temperature.3.1.2flow sensor (primary device)mechanical assembly co
38、nsisting of an oscillating tube(s), drive system, measurement sensor(s), supporting structure, and housing3.1.3transmitter (secondary device)electronic control system providing the drive electrical supply and transforming the signals from the flow sensor to give output(s) of measured and inferred pa
39、rametersNote 1 to entry: It also provides corrections derived from parameters such as temperature.Note 2 to entry: The transmitter (secondary device) is either integrally mounted (compact device) on the flow sensor (primary device) or remotely installed away from the primary device and connected by
40、a cable.INTERNATIONAL STANDARD ISO 10790:2015(E) ISO 2015 All rights reserved 1BS ISO 10790:2015ISO 10790:2015(E)3.1.4oscillating tubetube through which the fluid to be measured flows3.1.5drive systemmeans for inducing the oscillation of the tube(s)3.1.6sensing devicesensor to detect the effect of t
41、he Coriolis force and to measure the frequency of the tube oscillations3.1.7supporting structuresupport for the oscillating tube(s)3.1.8housingenvironmental protection of the flow sensor and/or transmitter3.1.9secondary containmenthousing designed to provide protection to the environment in the even
42、t of tube failure3.1.10calibrating factornumerical factor unique to each sensor derived during sensor calibrationNote 1 to entry: The calibrating factor is programmed into the transmitter to enable flowmeter operation.3.1.11zero offsetindicated flow when there are zero flow conditions present at the
43、 meterNote 1 to entry: This could be due to mechanical or electrical noise superimposed on the sensor output but equally could be due to installation effects such as torsional loading caused by improper torqueing of the flange bolts or temperature extremes creating deflection of the pipeline.3.1.12z
44、ero stabilityvariation of the flowmeter output at zero flow after the zero adjustment procedure has been completed, expressed by the manufacturer as an absolute value in mass per unit time3.1.13flashingphenomenon, which occurs when the line pressure drops to, or below, the vapour pressure of the liq
45、uidNote 1 to entry: This is often due to pressure drops caused by an increase in liquid velocity.Note 2 to entry: Flashing is not applicable to gases.3.1.14cavitationphenomenon related to and following flashing of liquids if the pressure recovers causing the vapour bubbles to collapse (implode)3.1.1
46、5flow ratequotient of the quantity of fluid passing through the cross-section of the conduit and the time taken for this quantity to pass through this section2 ISO 2015 All rights reservedBS ISO 10790:2015ISO 10790:2015(E)3.1.16mass flow rateflow rate in which the quantity of fluid is expressed as m
47、ass3.1.17volume flow rateflow rate in which the quantity of fluid is expressed as volume3.2 Definitions from VIM, ISO/IEC Guide 99 (JCGM:2012)3.2.1repeatability (condition of measurement)condition of measurement, out of a set of conditions that includes the same measurement procedure, same operators
48、, same measuring system, same operating conditions, and same location, and replicate measurements on the same or similar objects over a short period of timeNote 1 to entry: A condition of measurement is a repeatability condition only with respect to a specified set of repeatability conditions enviro
49、nmental protection of the flow sensor and/or transmitter.3.2.2measurement uncertaintynon-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information usedNote 1 to entry: Measurement uncertainty includes components arising from systematic effects, such as components associated with corrections and the assigned quantity values of measurement standards, as well as the definitional uncertainty. Sometimes estimated systematic effects are not corrected for but, instead, ass
