SIST EN 12729:2003
(Main)Devices to prevent pollution by backflow of potable water - Controllable backflow preventer with reduced pressure zone - Family B - Type A
Devices to prevent pollution by backflow of potable water - Controllable backflow preventer with reduced pressure zone - Family B - Type A
The purpose of this standard is to define - the field of application; - the dimensional, physico-chemical, design, hydraulic, mechanical and acoustic characteristics; - the working and the prescriptions for the tests to check , these characteristics; - the marking and the presentation. To be adhered to for reduced pressure principle backflow preventers, controllable BA.
Sicherungseinrichtungen zum Schutz des Trinkwassers gegen Verschmutzung durch Rückfließen - Systemtrenner mit kontrollierbarer druckreduzierter Zone - Familie B - Typ A
Diese Europäische Norm legt den Anwendungsbereich, die maßlichen und physikalisch-chemischen Anforde-rungen, die Anforderungen an die Konstruktion, die hydraulischen, mechanischen und akustischen Anforderungen für Systemtrenner mit kontrollierbarer druckreduzierter Zone, Familie B, Typ A fest.
Die vorliegende Norm gilt für Systemtrenner mit kontrollierbarer druckreduzierter Zone, Familie B, Typ A, die verhindern sollen, dass durch Rücksaugen oder Rückdrücken Wasser in das Trinkwasserversorgungsnetz zurückfließt, wenn der Druck in diesem Netz niedriger ist als in der nachgeschalteten Anlage.
Die Norm gilt für Systemtrenner der Nennweiten DN 8 bis DN 250.
Diese Norm gilt für Systemtrenner mit einem Nenndruck PN 10, die ohne Abänderung oder Nachstellung arbeiten:
3 bei jedem Druck bis 1 MPa (10 bar);
3 bei jeder Druckschwanking bis 1 MPa (10 bar);
3 der Dauerbelastung bei einer Grenztemperatur von 65 °C sowie bei 90 °C für den Zeitraum von 1 h.
Die Norm enthält ferner Festlegungen für die Prüfverfahren und Anforderungen zum Nachweis dieser Eigen-schaften, die Kennzeichnung und den Lieferzustand.
Dispositifs de protection contre la pollution par retour de l'eau potable - Disconnecteur a zone de pression réduite contrôlable - Famille B - Type A
La présente Norme européenne spécifie le domaine d'application, les caractéristiques dimensionnelles, physico-chimiques, de conception hydrauliques, mécaniques et acoustiques de disconnecteurs a zone de pression réduite contrôlable de Famille B, Type A.
La présente norme s'applique aux disconnecteurs de Famille B, Type A a zone de pression réduite contrôlable, destinés a empecher le retour d'une eau par contre pression ou siphonnage dans le réseau de distribution d'eau potable, lorsque la pression dans ce dernier est plus faible que dans le circuit placé en aval.
Elle est applicable aux disconnecteurs contrôlables de dénomination DN 8 a DN 250.
Elle s'applique aux disconnecteurs contrôlables de PN 10 qui doivent pouvoir fonctionner sans modification ni réglage :
a toute pression jusqu'a 1 MPa (10 bar) ;
pour toute variation de pression jusqu'a 1 MPa (10 bar) ;
en service continu a une température limite de 65 °C et de 90 °C pendant 1 h au maximum.
Elle spécifie également les méthodes d'essai et les exigences pour vérifier leurs caractéristiques, le marquage et la présentation a la livraison.
Naprave za varovanje pred onesnaženjem pitne vode zaradi povratnega toka - Sistemski ločevalnik z nadzorovanim območjem znižanega tlaka - Družina B - Tip A
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 12729:2003
01-oktober-2003
1DSUDYH]DYDURYDQMHSUHGRQHVQDåHQMHPSLWQHYRGH]DUDGLSRYUDWQHJDWRND
6LVWHPVNLORþHYDOQLN]QDG]RURYDQLPREPRþMHP]QLåDQHJDWODND'UXåLQD%7LS
$
Devices to prevent pollution by backflow of potable water - Controllable backflow
preventer with reduced pressure zone - Family B - Type A
Sicherungseinrichtungen zum Schutz des Trinkwassers gegen Verschmutzung durch
Rückfließen - Systemtrenner mit kontrollierbarer druckreduzierter Zone - Familie B - Typ
A
Dispositifs de protection contre la pollution par retour de l'eau potable - Disconnecteur a
zone de pression réduite contrôlable - Famille B - Type A
Ta slovenski standard je istoveten z: EN 12729:2002
ICS:
13.060.20 Pitna voda Drinking water
91.140.60 Sistemi za oskrbo z vodo Water supply systems
SIST EN 12729:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN 12729
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2002
ICS 13.060.20; 91.140.60
English version
Devices to prevent pollution by backflow of potable water -
Controllable backflow preventer with reduced pressure zone -
Family B - Type A
Dispositifs de protection contre la pollution par retour de Sicherungseinrichtungen zum Schutz des Trinkwassers
l'eau potable - Disconnecteur à zone de pression réduite gegen Verschmutzung durch Rückfließen - Systemtrenner
contrôlable - Famille B - Type A mit kontrollierbarer druckreduzierter Zone - Familie B - Typ
A
This European Standard was approved by CEN on 7 September 2002.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2002 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12729:2002 E
worldwide for CEN national Members.
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EN 12729:2002 (E)
Contents
page
Foreword.3
Introduction .4
1 Scope .5
2 Normative references .5
3 Terms and definitions.6
4 Denomination .7
5 Designation.7
6 Symbolization.7
7 Physico-chemical characteristics .8
7.1 Materials.8
7.2 Nature of the materials .8
8 Design .9
8.1 General.9
8.2 Relief valve .9
9 Characteristics and tests .10
9.1 General.10
9.2 General tolerances.10
9.3 Expression of the results.10
9.4 Dimensional characteristics .10
9.5 Mechanical characteristics .11
9.6 Tightness characteristics.15
9.7 Hydraulic characteristics .18
10 Order of testing .23
11 Marking and technical documents.24
11.1 Marking .24
11.2 Technical documents .24
12 Presentation at delivery .25
Annex A (informative) Examples of presentation of test results.26
Bibliography .32
2
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EN 12729:2002 (E)
Foreword
This document (EN 12729:2002) has been prepared by Technical Committee CEN/TC 164 "Water supply", the
secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by May 2003, and conflicting national standards shall be withdrawn at the latest by
May 2003.
The annex A is informative.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain,
Sweden, Switzerland and the United Kingdom.
3
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EN 12729:2002 (E)
Introduction
In respect of potential adverse effects on the quality of water intended for human consumption, caused by the
product covered by this standard:
a) this standard provides no information as to whether the product may be used without restriction in any of the
Member States of the EU or EFTA;
b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations
concerning the use and/or the characteristics of this product remain in force.
4
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EN 12729:2002 (E)
1 Scope
This European Standard specifies the field of application, the dimensional, the physico-chemical, the design, the
hydraulic, the mechanical, and the acoustic characteristics of controllable backflow preventer with reduced
pressure zone Family B Type A.
This standard covers controllable backflow preventers of Family B Type A, with reduced pressure zones, intended
to prevent backflow by backsiphoning or backpressure of water into the potable water distribution system whenever
the pressure of the latter is lower than the system located downstream.
It is applicable to controllable backflow preventers in denominations DN 8 up to DN 250.
It covers controllable backflow preventers of PN 10 that are capable of working without modification or adjustment:
at any pressure up to 1 MPa (10 bar);
with any pressure variation up to 1 MPa (10 bar);
in permanent duty at a limited temperature of 65 °C and 90 °C for 1 h maximum.
It specifies also the test methods and requirements for verifying their characteristics, the marking and the
presentation at delivery.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this European
Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 806-1:2000, Specifications for installations inside buildings conveying water for human consumption - Part 1:
General.
EN 1092-1, Flanges and their joints – Circular flanges for pipes, valves, fittings and accessories, PN designated –
Part 1: Steel flanges.
EN 1092-2, Flanges and their joints – Circular flanges for pipes, valves, fittings and accessories, PN designated –
Part 2: Cast iron flanges.
EN 1717:2000, Protection against pollution of potable water in water installations and general requirements of
devices to prevent pollution by backflow.
EN ISO 3822-1, Acoustics – Laboratory tests on noise emission from appliances and equipment used in water
supply installations - Part 1: Method of measurement (ISO 3822-1:1999).
EN ISO 3822-3:1997, Acoustics - Laboratory tests on noise emission from appliances and equipment used in water
supply installations - Part 3: Mounting and operating conditions for in-line valves and appliances
(ISO 3822-3:1997).
EN ISO 6509, Corrosion of metals and alloys - Determination of dezincification resistance of brass (ISO
6509:1981).
prEN 13959, Anti-pollution check valves DN 6 to DN 250 inclusive-Family E-Type A, B, C and D.
ISO 7-1, Pipe threads where pressure-tight joints are made on the threads - Part 1: Dimensions, tolerances and
designation.
5
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EN 12729:2002 (E)
ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads - Part 1: Dimensions, tolerances
and designation.
ISO 9227, Corrosion tests in artificial atmosphere - Salt spray tests.
3 Terms and definitions
For the purposes of this European Standard, the terms and definitions of EN 1717 and EN 806-1 together with the
following apply.
3.1
controllable backflow preventer with reduced pressure zone-Family B-Type A
the specific characteristics of this device called “BA”, (see Figure 1) are as follows:
3 pressure zones such that upstream p > intermediate p > downstream p (static no flow and under water flow
1 i 2
conditions);
p - p > 14 kPa (140 mbar);
1 i
connection from the intermediate pressure zone (p ) to the atmosphere when p - p £ 14 kPa (140 mbar);
i 1 i
disconnection by venting the intermediate pressure zone (p ) to the atmosphere when p shall be up to 14 kPa
i 1
(140 mbar);
a minimum set discharge flow (backflow rate);
devices that allow verification in every zone of the disconnection and the sealing of the protection devices
(obturators, discharge valves).
Key
1 Upstream zone p
1
2 Intermediate zone p
i
3 Downstream zone p
2
Figure 1 — Design principle
For the purposes of this standard «controllable backflow preventer BA» is hereafter referred to as «device».
6
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EN 12729:2002 (E)
4 Denomination
The denomination of the device is given in Table 1:
Table 1 — DN versus threads and flanges
Denomination DN 8 101520 253240
Threads 1/4 3/8 1/2 3/4 1 1 1
(designation in accordance 1/4 1/2
with ISO 7-1)
Flanges (DN) 40
Denomination DN 50 65 80 100 125 150 200 250
Threads 2
(designation in accordance
with ISO 7-1)
Flanges (DN) 50 65 80 100 125 150 200 250
NOTE For specifications of threads and flanges see 9.4.
5 Designation
A controllable backflow preventer with reduced pressure zone-Family B-Type A is designated by:
its name;
its family and its type;
its denomination (see Table 1);
its connection type;
the material of its body;
its surface finish (possible coating);
the acoustic group (for DN £ 32);
the reference to the present standard.
Examples for a designation:
Controllable backflow preventer with reduced pressure zone - Family B - Type A, DN 32, G 1"1/4 x G 1"1/4,
bronze, I, EN 12729.
Controllable backflow preventer with reduced pressure zone - Family B - Type A, DN100, flanged, cast iron, epoxy
coated, EN 12729.
6 Symbolization
The graphic representation of the controllable backflow preventer with reduced pressure zone-Family B-Type A is
as follows (see Figure 2):
7
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EN 12729:2002 (E)
Figure 2 — Graphic symbol
7 Physico-chemical characteristics
7.1 Materials
The materials and the coatings used, liable to come normally or accidentally in contact with potable water, shall
satisfy the EU regulations concerning water quality.
And therefore, they:
shall be corrosion resistant;
shall be prone to the least scaling possible;
shall be in conformity with the European Standards and regulations;
shall be compatible among themselves and:
with the water distribute;
with the fluids or matter liable to come into contact with them;
with the products normally used for disinfection operations of the networks : potassium permanganate and
sodium hypochlorite.
7.2 Nature of the materials
a) The choice of materials is left to the discretion of the manufacturer.
Copper-zinc alloys containing more than 10 % zinc are subject to dezincification when submitted to water
capable of dezincification. In the countries where the use of products made of dezincification resistant
materials is required, the products have to guarantee a dezincification depth less than 200 μm in any direction,
they have to be tested in accordance with EN ISO 6509 and have to be marked in compliance with the
indications in clause 11;
NOTE This standard does not cover non-metallic bodies.
b) neither the materials nor the coatings used shall, by normal or accidental contact with drinking water, cause
any risk of affecting or modifying the water up to a temperature of 90 °C. The suitability of the water for human
consumption is defined by national regulations;
c) the manufacturer shall state in his technical and sales literature the nature of the materials and the coatings
selected;
d) the materials, and in particular copper alloys, for which recommendations or international standard exists shall
comply with the relevant recommendations or international standards.
8
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EN 12729:2002 (E)
8 Design
8.1 General
a) The internal components of the device shall be accessible for inspection, repair or replacement; these
operations shall be possible on the device installed. To devices DN < 15 this requirement is considered to be
preferable. By design, the components shall be able to be refitted at their initial place, without ambiguity
(impossibility of reversal, interchange of obturators, diaphragms, springs, .). A visible mark is not sufficient;
b) the settings of the springs shall be fixed and not adjustable;
c) the device shall comprise three pressure tapings permitting periodic verification of the function of the device ;
They are placed:
upstream of the first check valve;
in the intermediate zone;
downstream of the second check valve.
d) it shall be possible to vent the air which can accumulate inside the device at the highest point of the device;
e) only the pressure of the water of the supply network can operate the control of the internal components of the
device;
f) possible additional control devices (electric, pneumatic, .) shall not adversely affect the backflow protection
function;
g) the device shall be installed horizontally bearing specific requirements of manufacturers for devices DN £ 50
which can be installed in the vertical position. The tests shall be carried out in the prescribed positions bearing
special indications in this standard.
8.2 Relief valve
The design of the relief valve operation shall be such that when the differential pressure over the upstream check
valve is less than 14 kPa (140 mbar) the relief valve shall be open to ensure positive safety.
An internal vertical distance h (in disconnected position) shall be provided between the highest point of the seat of
the relief valve and the lowest point of the seat of the upstream check valve:
h ‡ 5 mm for DN £ 15;
h ‡ 10 mm for 15 < DN £ 50;
h ‡ 20 mm for DN > 50.
In all the installation positions indicated by the manufacturer, any water retention shall not be possible within the
intermediate zone.
The cross sections of the passage orifices and of the pilot tube for operation the relief device shall be equal to or
2 2
greater than 45 mm with DN ‡ 15, or 12,5 mm with DN < 15 , no dimension for the calculation of the cross section
shall be less than 4 mm. The outside pilot tube shall be made so as not to be subject of any permanent deformation
or rupture under outside stresses.
An air break to drain shall exist between any waste drain and any means of collecting the discharged water (floor,
tundish, curb, sink, .).
9
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EN 12729:2002 (E)
The device with an air break to drain fitted shall evacuate the full relief flow rate as defined in 9.7.7 without spilling
to the outside.
The air break to drain shall meet the dimensional requirements as specified in EN 1717.
This air break to drain shall be:
either directly incorporated into the device;
or factory fitted;
or supplied with the device.
In the latter case, the relief orifice of the device shall permit, neither the fitting of a standardized threaded pipe, nor
the connection of a standardized pipe or shape, be it by glue, welding or interlocking.
9 Characteristics and tests
9.1 General
Performance tests shall be carried out on the device as installed in accordance with the manufacturer’s technical
documents, subject to dimension h being complied with.
If not specified all tests shall be performed with water at an ambient temperature.
9.2 General tolerances
9.2.1 Accuracy of measurements
In the absence of any particular specifications:
flow rate and pressure: – 2 % of the value specified;
temperature : cold water – 5 °C of the value specified;
hot water – 2 °C of the value specified;
+ 10%
time of the value specified.
0
9.2.2 Accuracy of measuring instruments
All the measuring instruments shall have an error limit of – 2 % of the measured value.
9.3 Expression of the results
The measured values shall be registered. These results can be expressed as a curve. See annex A for example.
9.4 Dimensional characteristics
9.4.1 Connections
The connections shall be in conformity with the following standards:
ISO 228-1;
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EN 12729:2002 (E)
ISO 7-1;
EN 1092-1;
EN 1092-2.
Devices with threaded connections shall be able to be dismounted without any damage to the piping. Example:
coupling nut, union.
9.4.2 Pressure taps
The devices shall have a pressure tap orifice per zone according to the indications as shown in Figure 3 and
Table 2.
2
The bores for pressure taps shall have over their full length a minimum cross-section of 12,56 mm . Their smallest
dimension shall be 4 mm.
Table 2 — Dimension of thread and test parts
DN Thread a
(designation in accordance mm
with ISO 7-1)
£ 10 G 1/8 ‡ 6,5
10 < DN £ 50 G 1/4 ‡ 6,5
G 1/2
> 50 ‡ 13
Key
G Thread
a Test part
Figure 3 — Pressure tap orifice
These tapings shall be fitted with 1/4 turn cocks:
DN 6 (G 1/8 connection) female outlet for preventers DN £ 10;
DN 8 (G 1/4 connection) female outlet for preventers 10 < DN £ 50;
DN 15 (G 1/2 connection) female outlet for preventers DN > 50.
9.5 Mechanical characteristics
Examples shown in the figures are for guidance only. Laboratory equipment shall be designed to ensure that the
device can be tested in accordance with the requirement.
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EN 12729:2002 (E)
9.5.1 Mechanical resistance of the body under pressure
9.5.1.1 Requirement
No visual permanent deformation, nor rupture of the body or the internal parts of the device shall occur.
The test shall be carried out under the conditions defined in 9.5.1.2.
9.5.1.2 Test method
Apply at the inlet of the device in increments of 0,1 MPa (1 bar) per 5 s an increase of the static water pressure
up to 2,5 times the PN , the value that equal 2,5 MPa (25 bar);
hold this pressure for 5 min. Observe the device and note any observations.
Verify that the device satisfies the requirement of 9.5.1.1.
9.5.2 Endurance
9.5.2.1 Requirement
a) Without replacement of any component, the device shall be capable of meeting the remaining requirements of
clause 10;
b) the device shall be disassembled, examined and any anomaly of the coating, elastomer parts and synthetic
materials, shall be noted.
9.5.2.2 Tests
Test 1 - Behaviour at temperature.
Place the complete device for 72 h in an environment at a temperature of 65 °C, and at a relative humidity of
(50 – 5) %.
Test 2 - Thermal shock.
Following the preceding test, put the complete device at the flow rate as given in the Table 3, supplying it with
water at 90 °C.
Once temperature reaches 85 °C at the outlet of the device, hold the flow rate for 60 min, and then supply for
10 min with water at 15 °C.
At the end the tests 1 and 2, verify that the device satisfies the requirement b) of 9.5.2.1.
Test 3 - Mechanical endurance.
A Supply flow; maximum pressure of 0,3 MPa (3 bar) at zero flow
B Supply pressure: 1 MPa – 0,05 MPa (10 bar – 0,5 bar)
C Supply pressure: 0,3 MPa – 0,03 MPa (3 bar – 0,3 bar)
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EN 12729:2002 (E)
Key
6 Adjusting valve
7 Valve with time control of opening and closing
Figure 4 — Endurance testing equipment
Following the preceding tests 1 and 2, submit the device placed in the testing equipment (see Figure 4) to
+ 50 cycles
5 000 cycles at a temperature of 65 °C, each cycle comprising:
0
Stage1 : Open valves 5 then 1, circulation at a flow rate as given in Table 3 at the value – 5 % for (6 – 2) s;
Stage 2 : Close valves 5 then 1;
Stage 3 : Open valve 3, static pressure at 0,3 MPa (3 bar) for (6 – 2) s;
Stage 4 : Close valve 3, open valve 4. Upstream drain for (6 – 2) s (opening of the relief valve);
Stage 5 : Close valve 4;
Stage 6 : Open valves 5 then 1, circulation at a flow rate as given in Table 3 at the value – 5 % for (6 – 2) s;
Stage 7 : Close valves 5 then 1;
Stage 8 : Open valve 2. Static pressure at 1 MPa (10 bar) for (6 – 2) s;
Stage 9 : Close valve 2, open valve 4. Upstream drain (opening of the relief valve) for (6 – 2) s;
Stage 10 : Close valve 4.
The 5 000 cycles are broken down into seven periods as follows:
1 250 cycles;
the device is at rest for 14 h at ambient temperature;
1 250 cycles;
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EN 12729:2002 (E)
the device is maintained under load at a static pressure of 1 MPa (10 bar) for 14 h at ambient temperature;
1 250 cycles;
the device is submitted for 14 h to an upstream pressure of 0,3 MPa (3 bar) and to a downstream pressure of
1 MPa (10 bar) at ambient temperature;
1 250 cycles.
Table 3 — Nominal size versus endurance test flow rate
DN 8 1015202532 4050
3
0,4 0,6 1,3 2,2 3,5 5,8 9 14
Flow rate m /h
DN 65 80 100 125 150 200 250
3
24 36 56 56 56 56 56
Flow rate m /h
At the end the test 3, verify that the device satisfies the requirements of 9.5.2.1.
9.5.3 Bending strength - Tightness of the body
9.5.3.1 Requirement
There shall be no rupture nor permanent deformation or leakage on the body of the device. The test shall be
carried out under the conditions defined in 9.5.3.2.
9.5.3.2 Test method
Fasten the device onto the test bench with the supplied connections (special unions are not allowed). Apply a load
W as shown in Figure 5 corresponding to the bending moment shown in Table 4, with a pressure of 1,6 MPa
(16 bar) applied in increments of 0,1 MPa (1 bar) per 5 s. Maintain the bending moment and the pressure for
10 min.
When calculating load W corresponding to the bending moment, loads introduced by the piping and taps and any
loads coming from the test apparatus shall be accounted for.
Key
W Load
Figure 5 — Bending moment testing equipment
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EN 12729:2002 (E)
Table 4 — Nominal size versus bending moment
DN 8 1015 2025324050
Bending
Threaded and
moment 30 40 80 150 300 400 500 -
flanged ends
Nm
DN 50 65 80 100 125 150 200 250
Bending
Threaded and
moment
600 750 950 1 300 1 800 2 400 3 800 5 500
flanged ends
Nm
Verify that the device satisfies the requirements of 9.5.3.1.
9.6 Tightness characteristics
9.6.1 Verification of the tightness of the downstream check valve (in the closing direction)
9.6.1.1 Requirement
Under the test conditions described below, no leakage nor permanent deformation or deterioration of the
downstream check valve shall occur.
9.6.1.2 Test
Downstream of the device, apply a pressure of 1,6 MPa (16 bar) with water at 20 °C, the upstream zone being at
atmospheric pressure. The pressure is to be applied in increments of 0,1 MPa (1 bar) per 5 s.
Hold the pressure for 2 min.
Isolate the device from the supply system for 10 min.
Verify that the device satisfies the requirements of 9.6.1.1.
9.6.2 Verification of the closing pressure of the downstream check valve and its tightness (opening
direction)
9.6.2.1 Requirement
The closing pressure of the check valve shall be greater than 7 kPa (70 mbar). If a check valve EB conforming to
prEN 13959 is incorporated, the closing pressure shall be greater than 0,5 kPa (5 mbar).
9.6.2.2 Test
The verification is made by measuring the difference in height between two levels (Figure 6).
0
The inside diameter of the level tubes shall be 10 mm.
- 2
15
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EN 12729:2002 (E)
a) b)
Figure 6 — Closing pressure testing equipment
Admit water to the device, so that the height h of the water column in tube C is obtained and sufficient to carry out
the two tests.
Isolate the device for 5 min – 30 s.
Note height D h (Figure 6 a)).
1
Drain slightly downstream.
Isolate for 5 min – 30 s.
Note height D h (Figure 6 b)).
2
Verify that the device satisfies the requirement of 9.6.2.1. The results can be expressed as a curve (see Figure A.1,
D h and D h remain higher than 70 cm WC or 5 cm WC if a check
for example). The tightness will be observed if
1 2
valve EB is incorporated.
9.6.3 Verification of the tightness of the upstream check valve at low pressure
9.6.3.1 Requirement
Under the test conditions, the tightness of the upstream check valve shall be verified by the water level in the tube
which shall be constant at each test stages.
No sagging of the water level in the tube shall be stated at each of the stages.
9.6.3.2 Test
Fill the device with water so that the water column has a height of (200 – 50) mm in the tube (diameter inside
0
10 _ mm), as shown on Figure 7.
2
Isolate for 5 min – 30 s.
Raise the level in the tube to (1 000 – 50) mm.
Isolate for 5 min – 30 s.
Raise the level in the tube to (2 000 – 50) mm.
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EN 12729:2002 (E)
Isolate for 5 min – 30 s.
Verify that the device satisfies the requirement of 9.6.3.1.
Key
1 Isolating valve
2 Adjusting valve
Figure 7 — Tightness testing equipment (low pressure)
9.6.4 Verification of the tightness of the upstream check-valve under vacuum
9.6.4.1 Requirement
Under the test conditions, the downstream check valve being dismantled, no water shall pass through the device as
verified by water not collected in the water trap.
9.6.4.2 Test
Place the device in the testing equipment (see Fig
...
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