SIST EN 13433:2022

SLOVENSKI STANDARD
oSIST prEN 13433:2020
01-junij-2020
Naprave za varovanje pitne vode pred onesnaženjem zaradi povratnega toka -
Mehanski ločilniki z neposrednim aktiviranjem - Družina G, tip A
Devices to prevent pollution by backflow of potable water - Mechanical disconnector,
direct actuated - Family G, type A
Sicherungseinrichtungen zum Schutz des Trinkwassers gegen Verschmutzung durch
Rückfließen - Rohrtrenner, nicht durchflussgesteuert - Familie G, Typ A
Dispositifs de protection contre la pollution par retour de l’eau potable - Disconnecteur
mécanique à action directe - Famille G, type A
Ta slovenski standard je istoveten z: prEN 13433
ICS:
13.060.20 Pitna voda Drinking water
23.060.50 Blokirni ventili Check valves
91.140.60 Sistemi za oskrbo z vodo Water supply systems
oSIST prEN 13433:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 13433:2020


DRAFT
EUROPEAN STANDARD
prEN 13433
NORME EUROPÉENNE

EUROPÄISCHE NORM

April 2020
ICS 23.060.50 Will supersede EN 13433:2006
English Version

Devices to prevent pollution by backflow of potable water
- Mechanical disconnector, direct actuated - Family G, type
A
Dispositifs de protection contre la pollution par retour Sicherungseinrichtungen zum Schutz des Trinkwassers
de l'eau potable - Disconnecteur mécanique à action gegen Verschmutzung durch Rückfließen -
directe - Famille G, Type A Rohrtrenner, nicht durchflussgesteuert - Familie G, Typ
A
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 164.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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 CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 13433:2020 E
worldwide for CEN national Members.

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Contents Page
European foreword . 3
Introduction . 4
7.2.1 Dezincification resistant copper alloy . 9
7.3.1 General. 9
7.3.2 Epoxy Coating . 10
7.3.3 Polyamide Powder based Coating . 10
8.2.1 General. 10
8.2.2 Mechanical Disconnector Family G, Type A . 11
9.2.1 Tolerance of set parameters . 11
9.2.2 Accuracy of measuring instruments . 11
9.3.1 Connections . 11
9.3.2 Pressure taps . 11
9.4.1 General. 12
9.4.2 Mechanical resistance of the body under pressure . 12
9.4.3 Endurance . 13
9.4.4 Torque test of Captive rotating Nuts and Bending Strength – Tightness of the Body . 14
9.5.1 Verification of the leak tightness of the downstream check valve in closing direction . 15
9.5.2 Verification of the leak tightness of check valve device (opening direction) . 15
9.5.3 Verification of the leak tightness of the upstream spring loaded obturator in drain
position at low pressure (in the opening direction) . 16
9.6.1 Test rig – General circuit . 17
9.6.2 Verification of the pressure loss as a function of flow rate . 18
9.6.3 Verification of the opening and closing pressures of relief valve . 19
9.6.4 Verification of the relief valve flow rate . 19
9.6.5 Compatibility with the products used for disinfection of water distribution systems . 20
9.6.6 Acoustic tests . 20
Annex A (informative) Examples of presentation of test results . 24
Bibliography . 27

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European foreword
This document (prEN 13433:2020) has been prepared by Technical Committee CEN/TC 164 “Water
supply”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 13433:2006.
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Introduction
In respect of potential adverse effects on the quality of water intended for human consumption caused
by the product covered by this document:
1) this document provides no information as to whether the product can be used without restriction
in any of the member states of the EU or EFTA;
2) 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.
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1 Scope
This document specifies the dimensional, physical-chemical, design, hydraulic, mechanical and acoustic
characteristics of mechanical disconnectors, direct actuated Family G, type A.
This document is applicable to mechanical disconnectors in nominal sizes DN 8 up to DN 250, intended
to prevent the return of water having lost its original sanitary and drinking qualities (called “polluted
water” in this document), into the potable water distribution system whenever the pressure of the
latter is temporarily lower than in the polluted circuit.
This document covers the mechanical disconnector of PN 10 that are capable of working without
modification or adjustment:
— at any pressure up to 1,0 MPa (10 bar);
— with any pressure variation up to 1,0 MPa (10 bar);
— in permanent duty at a limit temperature of 65 °C and 90 °C for 1 h maximum.
It specifies also the test methods and requirements for verifying these characteristics, the marking and
the presentation at delivery.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 806-1, Specifications for installations inside buildings conveying water for human consumption - Part
1: General
EN 1329-1, Plastics piping systems for soil and waste discharge (low and high temperature) within the
building structure - Unplasticized poly(vinyl chloride) (PVC-U) - Part 1: Specifications for pipes, fittings
and the systems
EN 1453-1, Plastics piping systems with structured-wall pipes for soil and waste discharge (low and high
temperature) inside buildings - Unplasticized poly(vinyl chloride) (PVC-U) - Part 1: Specifications for pipes
and the system
EN 1717:2000, Protection against pollution of potable water in water installations and general
requirements of devices to prevent pollution by backflow
EN 10310, Steel tubes and fittings for onshore and offshore pipelines - Internal and external polyamide
powder based coatings
EN 13959, Anti-pollution check valves - DN 6 to DN 250 inclusive family E, type A, B, C and D
EN 14901-1:2014+A1:2019, Ductile iron pipes, fittings and accessories - Requirements and test methods
for organic coatings of ductile iron fittings and accessories - Part 1: Epoxy coating (heavy duty)
EN ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads - Part 1: Dimensions,
tolerances and designation (ISO 228-1)
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)
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EN ISO 3822-3:2018, 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 3822-3:2018)
EN ISO 6509-1, Corrosion of metals and alloys - Determination of dezincification resistance of copper
alloys with zinc - Part 1: Test method (ISO 6509-1)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 1717, EN 806-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
mechanical disconnector, direct actuated — Family G, type A
device, also referred to as "GA", the characteristics of which are as follows:
— two pressure zones in flow position: upstream (zone 1) and downstream (zone 2);
— two pressure zones in zero flow position (static): upstream (zone 1) and downstream (zone 2),
check valve closed;
— three pressure zones in drain position: upstream (zone 1) and downstream (zone 2) and
intermediate zone (zone 3) at atmospheric pressure;
— the upstream spring loaded obturator with discharge system and the downstream (zone 2) check
valve separate the intermediate zone (zone 3) from the upstream (zone 1) and downstream zone
(zone 2);
— flow position is achieved at a pressure p ≥ p + 50 kPa (0,5 bar);
f s
— the relief valve starts opening at the set pressure p ≥ p + 50 kPa (0,5 bar);
s stat
— drain position is achieved at a pressure p ≥ p − 36 kPa (0,36 bar);
0 s
— a determined relief flow rate;
— a drain position visible directly or by a position indicator
Note 1 to entry: See Figure 1.
Note 2 to entry: For the purposes of this standard “Mechanical disconnector, direct actuated — Family G,
type A” are hereafter referred to as “device”.
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Key
1, 2, 3 pressure zones
D disconnection distance
Figure 1 — Design principle of Mechanical disconnector, direct actuated – Family G, type A
3.2
inlet pressure
p
1
pressure on upstream (inlet side, zone 1) of the device
3.3
intermediate pressure
p
i
pressure in the intermediate chamber of the device (in drain position p = p and under flow
i atm.
condition p = p (zone 3))
i 1
3.4
outlet pressure
p
2
pressure on the downstream (outlet side, zone 2) of the device
3.5
differential pressure
Δp
differential pressure between the inlet pressure p and the outlet pressure p
1 2
3.6
static pressure
p
stat
pressure equivalent to the height of the water column between the highest draw-off point and the
horizontal axis of the installed disconnector
3.7
set pressure
p
s
pressure at which the relief valve starts to open
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3.8
opening pressure
p
o
pressure at which the disconnection distance of ≤ 20 mm is reached
3.9
closing pressure
p
f
pressure at which the relief valve is fully closed
3.10
disconnection distance
D
minimal vertical distance between the seat 1 of the relief valve and the seat 2 (see Figure 1) of the
upstream zone
4 Denomination
For the purpose of this document for the devices the nominal sizes DN is a function of the minimum
flow rate given in Table 5.
5 Designation
Mechanical disconnectors direct actuated family G, type A are designated by:
— name;
— reference to this document, EN 13433;
— family and type;
— nominal size;
— connection type;
— material of its body;
— surface finish (possible coatings);
— acoustic group (if applicable).
EXAMPLE Mechanical disconnector direct actuated family G type A, DN 32, G 1 1/4 × G 1 1/4, brass, I,
EN 13433.
6 Symbolization
The graphic representation of the mechanical disconnector direct actuated, Family G, Type A is as
follows (see Figure 2):
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Figure 2 — Graphic symbol design principle of mechanical disconnector
7 Physical-chemical characteristics
7.1 General
The selection of materials is the responsibility of the manufacturer, provided they satisfy the following
requirements:
a) materials and coatings shall not contaminate the potable water;
b) in a technical document, the manufacturer shall state the nature of the materials and coatings used;
c) materials with inadequate corrosion resistance shall have additional protection;
d) the materials used shall be suitable for the temperatures specified in the tests in this Standard;
e) The materials, and in particular copper alloys, for which recommendations or international
standards exist, shall comply with the relevant European standards.
7.2 Materials
7.2.1 General
All materials coming into contact with water intended for human consumption shall present no health
risk nor cause any change to the water in terms of quality, appearance, smell or taste.
NOTE While awaiting the adoption of verifiable European criteria for testing materials in contact with water
intended for human consumption, existing national regulations concerning the use and/or the characteristics of
these products remain in force.
7.2.2 Dezincification resistant copper alloy
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 materials used shall guarantee a dezincification depth less than
200 μm in any direction. For this purpose materials shall be tested in accordance with the standard
EN ISO 6509-1 and the product shall be marked in compliance with the indications according to
Clause 11.
7.3 Surface of the body
7.3.1 General
The outside and inside surfaces of the device may or may not contain a coating. Such coating shall not
impair the functional characteristics of the device.
The coating for protection of the basic material against corrosion can be either realized by epoxy
coating or by polyamide powder based coating.
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7.3.2 Epoxy Coating
Epoxy Coating shall fulfil the requirements of and be tested in accordance with
EN 14901-1:2014+A1:2019 (see Table A.1 in Annex A).
7.3.3 Polyamide Powder based Coating
Polyamide powder shall fulfil the requirements of and be tested in accordance with EN 10310 (see
Table A.1 in Annex A).
8 Design
8.1 General
a) The internal components of the device shall be accessible for inspection, repair or replacement. By
design, the components shall be able to be refitted at their initial place, without ambiguity
(impossibility of reversal, interchange of obturators, diaphragms, and springs). A visible mark is
not sufficient.
b) The settings of the springs shall be fixed and not adjustable.
c) The device shall comprise one pressure tapping and a visible indication on the device when the
obturator is in the drain position. The pressure tapping is located on the inlet of the device.
d) Only the pressure of the water of the supply system at the inlet can operate the control of the
internal components of the device.
8.2 Relief valve/Obturator
8.2.1 General
Any water retention shall not be possible within the intermediate zone.
An air break to drain shall exist between any waste drain and any means of collecting the discharged
water (floor, tundish, curb, sink).
The device with an air break to drain fitted shall evacuate the full relief flow rate as defined in 9.6.4.
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 adhesive, welding or
interlocking.
If applicable on the dimension “G” of the outlet of the air break to drain (see in EN 1717:2000, Clause 9),
it shall be possible to fit a standardized drain pipe (Standard EN 1329-1 PVC compact and EN 1453-1
PVC with structured walls).
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8.2.2 Mechanical Disconnector Family G, Type A
Under normal service conditions at p > p the relief valve is closed. At an inlet pressure of p ≤ p the
1 s 1 s
relief valve starts opening and at a pressure of p ≤ p the relief valve is in drain position. There shall be
1 o
a visible indication on the device, when the obturator is in the drain position, any water retention shall
not be possible within the intermediate zone.
8.3 Disconnection distance
In drain position the obturator shall close the opening from upstream zone to the intermediate zone.
The disconnection distance D shall be at least 20 mm (see Figure 1).
The relief valve shall be closed, before flow condition is achieved. The passage orifice of the relief
valve shall be at least equal to the minimum cross-section of the outlet water way (downstream).
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.
If not specified all tests shall be performed with water at ambient temperature.
9.2 General tolerances
9.2.1 Tolerance of set parameters
In the absence of any particular specifications given in this document:
— 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
Instruments for measuring temperature shall be accurate to 1 °C. All other measuring instruments shall
have an error limit of ± 2 % of the measured value.
9.3 Dimensional characteristics
9.3.1 Connections
The connections shall be in accordance with the relevant European Standards.
9.3.2 Pressure taps
The device shall have a pressure tapping orifice in the upstream zone according to the indications as
shown in Figure 3 and Table 1.
The bores for pressure tapping shall have over their full depth a minimum cross-section area of
2
12,56 mm . Their smallest dimension shall be 4 mm.
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Table 1 — Dimension of thread and test parts
Thread
a
DN
(designation in accordance with
mm
EN ISO 228-1)
≤ 10 G 1/8 > 6,5
10 ≤ DN ≤ 50 G 1/4 > 6,5
> 50 G 1/2 > 13

Key
G thread
a minimum thread length of test par
Figure 3 — Pressure tapping orifice
These pressure tappings shall be fitted with isolating valves:
— DN 6 (G 1/8 connection) female outlet for devices DN ≤ 10;
— DN 8 (G 1/4 connection) female outlet for devices 10 < DN ≤ 50;
— DN 15 (G 1/2 connection) female outlet for device DN > 50;
or other technical means for the verification of the device e.g. fast couplings or removable plugs.
9.4 Mechanical characteristics
9.4.1 General
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.
If there is no other specification all tests shall be performed with potable water at maximum
temperature 30 °C.
9.4.2 Mechanical resistance of the body under pressure
9.4.2.1 Requirement
There shall be no visual permanent deformation or rupture of the body or the internal parts of the
device. Procedure
— 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 rating, the value that equals 2,5 MPa (25 bar).
— Hold this pressure for 5 min. and observe the device and note any observations.
Verify that the device satisfies the requirement of 9.4.2.1.
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9.4.3 Endurance
9.4.3.1 Requirement
a) The endurance test shall be done with the same sample that has been tested according to the
clauses 9.5.1, 9.5.2, 9.5.3., 9.6.3 and 9.6.5. After performing the test according to Clause 9.4.3.2. The
sample shall fulfil the requirements according to clauses 9.5.1, 9.5.2, 9.5.3 and 9.6.3.
b) There shall be no visible damages or deformation of the coating, and of components.
9.4.3.2 Procedures
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 ± 10) %.
Test 2 — Thermal shock.
Following the preceding test, put the complete device at the flow rate as given in the Table 4, 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.
Test 3 — Mechanical endurance
A Supply pressure: (0,3 ± 0,03) MPa (3 ± 0,3) bar
B Supply pressure: (1 ± 0,05) MPa (10 ± 0,5) bar

Key
1, 2, 3, 4 valve with time control of opening and closing
5 adjusting valve
Figure 4 — Endurance testing equipment
Following the preceding test 1 and test 2 submit the device placed in the test equipment (see Figure 4 to
+ 50
5 000 cycles cycles at a temperature of 40 °C with a flow rate given in Table 2 ± 5 % (adjust with
0
valve 5), each cycle comprising:
— stage 1: open valves 1 and 4; flow condition;
— stage 2: close valves 1 and 4;
— stage 3: open valve 1, static pressure of 0,3 MPa (3 bar) for (6 ± 2) s; static condition at 3 bar;
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— stage 4: close valve 1, open valve 3; Upstream drain for 2 s; Disconnection;
— stage 5: close valve 3;
— stage 6: open valve 4; downstream drain to atmospheric pressure;
— stage 7: open valve 1; circulation at a flow rate given in Table 2 at the value ± 5 % for (6 ± 2) s;
— stage 8: close valve 4 and 1;
— stage 9: open valve 2, static pressure of 1 MPa (10 bar) for (6 ± 2) s;
— stage 10: close valve 2 and open valve 3, Upstream drain for 2 s; Disconnection;
— stage 11: close valve 3, open valve 4
+50
— continue with stage 1 until 5 000 cycles are achieved.
Table 2 — Nominal size versus endurance test flow rate
Type DN 8 10 15 20 25 32 40 50 65 80 100 125 150 200 250
Flow
GA rate 0,4 0,6 1,3 2,2 3,5 5,8 9 14 24 35 56 56 56 56 56
3
m /h
At the end of test 3, verify that the device satisfies the requirements of 9.4.3.1.
9.4.4 Torque test of Captive rotating Nuts and Bending Strength – Tightness of the Body
9.4.4.1 Requirement
a) After unscrewing, no visual damage of the nut shall be detected.
b) 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 9.4.4.2.
9.4.4.2 Test method
The device shall be fixed to the test rig, into operating orientation, as shown in Figure 5, captive rotating
nut connection shall be tightened with the torque specified in Table 3. Gradually apply torque to the
captive rotating nut/backnut until the tightening torque is reached and maintain it for a period of at
least 1 min.
Once it is in water under pressure and without bending stress, the fitting shall be leaktight. In case it is
not leaktight, the tightening torque can be increased.
Apply a load W as shown in Figure 5 corresponding to the bending moment shown in Table 4. Apply
pressure up to 1,6 MPa (16 bar) with increments of 0,1 MPa (1 bar) per 5 s.
Maintain bending moment and 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.
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Table 3 — Tightening torque
Nominal size DN 15 20 25 32 40 50
Tightening torque (Nm) 60 75 100 125 150 150

Key
W load
Figure 5 — Bending moment testing equipment
Table 4 — Nominal size versus bending moment
Nominal
8 10 15 20 25 32 40 50 65 80 100 125 150 200 250
size DN
Bending
1 30 1 80 2 40 3 80 5 50
Moment 30 40 70 110 150 250 300 500 750 950
0 0 0 0 0
(Nm)
Verify that the device satisfies the requirements of 9.4.4.
9.5 Leak tightness characteristics
9.5.1 Verification of the leak tightness of the downstream check valve in closing direction
9.5.1.1 Requirement
Under the test conditions described in 9.5.1.2, the device shall show no leakage, nor permanent
deformation or deterioration.
9.5.1.2 Procedure
Downstream of the device, apply a pressure of 1,6 MPa (16 bar) with water at maximum 30 °C, the
upstream zone and intermediate zone being at atmospheric pressure. The pressure is to be applied in
increments of 0,1 MPa (1 bar) per 5 s until 1,6 MPa (16 bar) is reached.
Isolate the device from the supply system and hold the pressure for 10 min.
Verify that the device satisfies the requirements of 9.5.1.1.
9.5.2 Verification of the leak tightness of check valve device (opening direction)
9.5.2.1 Requirement
The closing pressure of the check valve shall be greater than 7 kPa (70 mbar). If a check valve EB
conforming to EN 13959 is incorporated, the closing pressure shall be greater than 0,5 kPa (5 mbar).
The differential pressure shall be constant for minimum of 5 min.
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a) b)
Figure 6 — Test equipment for verifying closing pressure
9.5.2.2 Procedure
The verification is made with the device fixed in the flow position by measuring the differential
pressure between the upstream and downstream zone (Figure 6).
Keep the obturator in flow position.
Admit water to the device and fix it in flow position.
Isolate the device for 5 min + 30 s from water
...