NF EN ISO 5167-2
Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full - Part 2 : orifice plates
ISO 5167-2:2003 specifies the geometry and method of use (installation and operating conditions) of orifice plates when they are inserted in a conduit running full to determine the flow-rate of the fluid flowing in the conduit.It also provides background information for calculating the flow-rate and is applicable in conjunction with the requirements given in ISO 5167-1.ISO 5167-2:2003 is applicable to primary devices having an orifice plate used with flange pressure tappings, or with corner pressure tappings, or with D and D/2 pressure tappings. Other pressure tappings such as vena contracta and pipe tappings have been used with orifice plates but are not covered by ISO 5167-2:2003. ISO 5167-2:2003 is applicable only to a flow which remains subsonic throughout the measuring section and where the fluid can be considered as single phase. It is not applicable to the measurement of pulsating flow. It does not cover the use of orifice plates in pipe sizes less than 50 mm or more than 1 000 mm, or for pipe Reynolds numbers below 5 000.
ISO 5167-2:2003 specifies the geometry and method of use (installation and operating conditions) of orifice plates when they are inserted in a conduit running full to determine the flow-rate of the fluid flowing in the conduit.
It also provides background information for calculating the flow-rate and is applicable in conjunction with the requirements given in ISO 5167-1.
ISO 5167-2:2003 is applicable to primary devices having an orifice plate used with flange pressure tappings, or with corner pressure tappings, or with D and D/2 pressure tappings. Other pressure tappings such as vena contracta and pipe tappings have been used with orifice plates but are not covered by ISO 5167-2:2003.
ISO 5167-2:2003 is applicable only to a flow which remains subsonic throughout the measuring section and where the fluid can be considered as single phase. It is not applicable to the measurement of pulsating flow. It does not cover the use of orifice plates in pipe sizes less than 50 mm or more than 1 000 mm, or for pipe Reynolds numbers below 5 000.
Ce premier amendement à la norme ISO 5167-1:1991, permet un calcul amélioré du coefficient de décharge C. En outre, ce coefficient peut désormais être appliqué pour des nombres de Reynolds rapportés au diamètre de la conduite inférieures à 4 000 d'une part et d'autre part le rapport de diamètre beta = d/D doit être toujours supérieur ou égal à 0,10 et inférieur ou égal à 0,75.
This document specifies the geometry and method of use (installation and operating conditions) of orifice plates when they are inserted in a conduit running full to determine the flow rate of the fluid flowing in the conduit. This document also provides background information for calculating the flow rate and is applicable in conjunction with the requirements given in ISO 5167‑1. This document is applicable to primary devices having an orifice plate used with flange pressure tappings, or with corner pressure tappings, or with D and D/2 pressure tappings. Other pressure tappings such as “vena contracta” and pipe tappings are not covered by this document. This document is applicable only to a flow which remains subsonic throughout the measuring section and where the fluid can be considered as single phase. It is not applicable to the measurement of pulsating flow[1]. It does not cover the use of orifice plates in pipe sizes less than 50 mm or more than 1 000 mm, or where the pipe Reynolds numbers are below 5 000.
- Avant-proposiv
- Introductionv
- Domaine d'application
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2 Références normatives
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3 Termes, définitions et symboles2
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4 Principes de la méthode de mesurage et mode de calcul2
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5 Diaphragmes2
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5.1 Description3
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5.2 Prises de pression6
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5.3 Coefficients et incertitudes correspondantes des diaphragmes10
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5.4 Perte de pression, 0tu14
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6 Exigences d'installation16
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6.1 Généralités16
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6.2 Longueurs droites minimales d'amont et d'aval à installer entre différents accessoires et le diaphragme16
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6.3 Conditionneurs d'écoulement21
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6.4 Circularité et cylindricité de la conduite28
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6.5 Emplacement du diaphragme et des bagues porteuses29
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6.6 Mode de fixation et joints30
- Annexe A (informative) Tableaux des coefficients de décharge et des coefficients de détente31
- Annexe B (informative) Conditionneurs d'écoulement43
- Bibliographie49
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