EN 60534-2-1:1998
(Main)Industrial-process control valves - Part 2-1: Flow capacity - Sizing equations for fluid flow under installed conditions
Industrial-process control valves - Part 2-1: Flow capacity - Sizing equations for fluid flow under installed conditions
Includes equations for predicting the flow of compressible and incompressible fluids through control valves. They are not intended for use when non-Newtonian fluids, fluid mixtures, slurries or liquid-solid conveyance systems are encountered. The equations for compressible fluids are for use with gas or vapour and are not intended for use with multiphase streams such as gas-liquid, vapour-liquid or gas-solid mixtures.
Stellventile für die Prozeßregelung - Teil 2-1: Durchflußleistung - Bemessungsgleichungen für Fluide unter Einbaubedingungen
Vannes de régulation des processus industriels - Partie 2-1: Capacité d'écoulement - Equations de dimensionnement pour l'écoulement des fluides dans les conditions d'installation
Comprend des équations permettant de prédire le débit de fluides compressibles et incompressibles dans les vannes de régulation. N0e sont pas destinées à être utilisées pour des fluides on newtoniens, des mélanges de fluides, des boues ou des systèmes de transport de particules solides en suspension dans un liquide. Les équations présentées d'appliquent aux gaz ou aux vapeurs, mais ne conviennent pas pour les fluides multiphasiques tels que les mélanges gaz-liquide, vapeur-liquide ou gaz-solide.
Industrial-process control valves - Part 2-1: Flow capacity - Sizing equations for fluid flow under installed conditions
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-april-2001
1DGRPHãþD
SIST EN 60534-2-1:1998
SIST EN 60534-2-2:1998
Industrial-process control valves - Part 2-1: Flow capacity - Sizing equations for
fluid flow under installed conditions
Industrial-process control valves -- Part 2-1: Flow capacity - Sizing equations for fluid
flow under installed conditions
Stellventile für die Prozeßregelung -- Teil 2-1: Durchflußleistung -
Bemessungsgleichungen für Fluide unter Einbaubedingungen
Vannes de régulation des processus industriels -- Partie 2-1: Capacité d'écoulement -
Equations de dimensionnement pour l'écoulement des fluides dans les conditions
d'installation
Ta slovenski standard je istoveten z: EN 60534-2-1:1998
ICS:
23.060.40 7ODþQLUHJXODWRUML Pressure regulators
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
IEC 60534-2-1
Edition 1.0 1998-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial-process control valves –
Part 2-1: Flow-capacity – Sizing equations for fluid flow under installed
conditions
Vannes de régulation des processus industriels –
Partie 2-1: Capacité d’écoulement – Equations de dimensionnement pour
l’écoulement des fluides dans les conditions d’installation
IEC 60534-2-1:1998
IEC 60534-2-1
Edition 1.0 1998-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial-process control valves –
Part 2-1: Flow-capacity – Sizing equations for fluid flow under installed
conditions
Vannes de régulation des processus industriels –
Partie 2-1: Capacité d’écoulement – Equations de dimensionnement pour
l’écoulement des fluides dans les conditions d’installation
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
X
CODE PRIX
ICS 23.060.40; 25.040.40 ISBN 2-8318-4751-6
60534-2-1 © IEC:1998 – 3 –
CONTENTS
Page
FOREWORD . 5
Clause
1 Scope . 7
2 Normative references . 7
3 Definitions. 9
4 Installation . 9
5 Symbols . 11
6 Sizing equations for incompressible fluids. 13
7 Sizing equations for compressible fluids . 17
8 Determination of correction factors . 21
Annex A (informative) Derivation of valve style modifier F . 49
d
Annex B (informative) Control valve sizing flow charts. 59
Annex C (informative) Physical constants . 67
Annex D (informative) Examples of sizing calculations . 69
Annex E (informative) Bibliography . 91
60534-2-1 © IEC:1998 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
––––––––––––
INDUSTRIAL-PROCESS CONTROL VALVES –
Part 2-1: Flow capacity – Sizing equations for fluid flow
under installed conditions
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60534-2-1 has been prepared by subcommittee 65B: Devices, of
IEC technical committee 65: Industrial-process measurement and control.
IEC 60534-2-1 cancels and replaces the first edition of both IEC 60534-2, published in 1978,
and IEC 60534-2-2, published in 1980, which covered incompressible and compressible fluid
flow, respectively.
IEC 60534-2-1 covers sizing equations for both incompressible and compressible fluid flow.
This bilingual version, published in 1999-03, corresponds to the English version.
The text of this standard is based on the following documents:
FDIS Report on voting
65B/347/FDIS 65B/357/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
Annexes A, B, C, D and E are for information only.
The contents of the corrigendum of February 2000 have been included in this copy.
60534-2-1 © IEC:1998 – 7 –
INDUSTRIAL-PROCESS CONTROL VALVES –
Part 2-1: Flow capacity – Sizing equations for fluid flow
under installed conditions
1 Scope
This part of IEC 60534 includes equations for predicting the flow of compressible and
incompressible fluids through control valves.
The equations for incompressible flow are based on standard hydrodynamic equations for
Newtonian incompressible fluids. They are not intended for use when non-Newtonian fluids,
fluid mixtures, slurries or liquid-solid conveyance systems are encountered.
At very low ratios of pressure differential to absolute inlet pressure (Δp/p ), compressible fluids
behave similarly to incompressible fluids. Under such conditions, the sizing equations for
compressible flow can be traced to the standard hydrodynamic equations for Newtonian
incompressible fluids. However, increasing values of Δp/p result in compressibility effects
which require that the basic equations be modified by appropriate correction factors. The
equations for compressible fluids are for use with gas or vapour and are not intended for use
with multiphase streams such as gas-liquid, vapour-liquid or gas-solid mixtures.
For compressible fluid applications, this part of IEC 60534 is valid for valves with x ≤ 0,84
T
(see table 2). For valves with x > 0,84 (e.g. some multistage valves), greater inaccuracy of
T
flow prediction can be expected.
2 2
Reasonable accuracy can only be maintained for control valves if K /d < 0,04 (C /d < 0,047).
v v
2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 60534. For dated references, subsequent amendments
to, or revisions of, any of these publications do not apply. However, parties to agreements
based on this part of IEC 60534 are encouraged to investigate the possibility of applying the
most recent editions of the normative documents indicated below. For undated references, the
latest edition of the normative document referred to applies. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60534-1:1987, Industrial-process control valves – Part 1: Control valve terminology and
general considerations
IEC 60534-2-3:1997, Industrial-process control valves – Part 2: Flow capacity – Section 3: Test
procedures
60534-2-1 © IEC:1998 – 9 –
3 Definitions
For the purpose of this part of IEC 60534, definitions given in IEC 60534-1 apply with the
addition of the following:
3.1
valve style modifier F
d
the ratio of the hydraulic diameter of a single flow passage to the diameter of a circular orifice,
the area of which is equivalent to the sum of areas of all identical flow passages at a given
travel. It should be stated by the manufacturer as a function of travel. See annex A
4 Installation
In many industrial applications, reducers or other fittings are attached to the control valves. The
effect of these types of fittings on the nominal flow coefficient of the control valve can be
significant. A correction factor is introduced to account for this effect. Additional factors are
introduced to take account of the fluid property characteristics that influence the flow capacity
of a control valve.
In sizing control valves, using the relationships presented herein, the flow coefficients calculated
are assumed to include all head losses between points A and B, as shown in figure 1.
Flow
l l
I
I1 2 Pressure
2 Pressur
Pressur
Pressure
tap
tap
tap
tap
A B
Control valve with or without attached fittings
IEC 588/99
l = two nominal pipe diameters
l = six nominal pipe diameters
Figure 1 – Reference pipe section for sizing
60534-2-1 © IEC:1998 – 11 –
5 Symbols
Symbol Description Unit
C Flow coefficient (K , C ) Various (see IEC 60534-1)
v v
(see note 4)
C Assumed flow coefficient for iterative purposes Various (see IEC 60534-1)
i
(see note 4)
d Nominal valve size mm
D Internal diameter of the piping mm
D Internal diameter of upstream piping mm
D Internal diameter of downstream piping mm
D Orifice diameter mm
o
Valve style modifier (see annex A) 1 (see note 4)
F
d
F Liquid critical pressure ratio factor 1
F
F Liquid pressure recovery factor of a control valve without attached fittings 1 (see note 4)
L
F Combined liquid pressure recovery factor and piping geometry factor of a 1 (see note 4)
LP
control valve with attached fittings
F Piping geometry factor 1
P
F Reynolds number factor 1
R
F Specific heat ratio factor 1
γ
M Molecular mass of flowing fluid kg/kmol
N Numerical constants (see table 1) Various (see note 1)
p Inlet absolute static pressure measured at point A (see figure 1) kPa or bar (see note 2)
p Outlet absolute static pressure measured at point B (see figure 1) kPa or bar
p Absolute thermodynamic critical pressure kPa or bar
c
p Reduced pressure (p /p ) 1
r 1 c
p Absolute vapour pressure of the liquid at inlet temperature kPa or bar
v
Differential pressure between upstream and downstream pressure taps kPa or bar
Δp
(p – p )
1 2
Q Volumetric flow rate (see note 5) m /h
Re Valve Reynolds number 1
v
T Inlet absolute temperature K
T Absolute thermodynamic critical temperature K
c
T Reduced temperature (T /T ) 1
r 1 c
t Absolute reference temperature for standard cubic metre K
s
W Mass flow rate kg/h
x 1
Ratio of pressure differential to inlet absolute pressure (Δp/p )
x Pressure differential ratio factor of a control valve without attached fittings 1 (see note 4)
T
at choked flow
x Pressure differential ratio factor of a control valve with attached fittings at 1 (see note 4)
TP
choked flow
60534-2-1 © IEC:1998 – 13 –
Symbol Description Unit
Expansion factor 1
Y
Z Compressibility factor 1
Kinematic viscosity m /s (see no
...
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