PIETRO FIORENTINI APERFLUX 851 Guide

PRESSURE REGULATOR
APERFLUX 851
TECHNICAL MANUAL MT049
INSTALLATION, COMMISSIONING AND MAINTENANCE INSTRUCTIONS
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TECHNICAL MANUAL MT049
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APERFLUX 851
INLET PRESSURE OUTLET PRESSURECONTROL PRESSURE
AR 73
304/A
302/A
Issue October 2002
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TECHNICAL MANUAL MT049
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The PIETRO FIORENTINI SPA with registered office in Milan (Italy) – via Rosellini, 1, declares under its sole
responsibility that the apparatus series Aperflux 851 bearing the CE marking showed in this manual are designed,
manufactured, tested and inspected in accordance with the provisions of Pressure Equipment Directive 97/23/EC
(PED).
Following conformity assessment procedure has been carried out:
➤EC type-examination (module B) by DVGW Forschungsstelle Richard –Wilstätter –Allee 5, 76131 Karlsruhe
–report 02/140a/4301/855 issued 3rd May 2002. In this report both the versions incorporating the safety
shut-off devices series SB/82 or HB/97 when controlling overpressure and the monitor PM/819, are
classified as safety accessories according to clause 2.1.3 of art. 1 of PED.
➤Production quality assurance (module D) by BUREAU VERITAS (ID n°0062) –Attestation d’Approbation
du Système QualitéN°CE-PED-D-FIO001-02-ITA Rev. A issued 15th May 2002.
Further we declare that the classification of the performances characteristics has been verified by DVGW
according to the procedures given by European standard EN 334 and/or by standard DIN 3381 and, only for the safety
device HB/97, also according to the procedure given by prEN 14382. The classification is detailed in the aforesaid
DVGW report.
Arcugnano 25/9/2002 The Pietro Fiorentini SpA
DECLARATION OF CONFORMITY
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TECHNICAL MANUAL MT049
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GENERAL PRECAUTIONS
- The apparatus described in this manual is a device subject to pressure installed in systems under pressure;
- the apparatus in question is normally installed in systems for transporting flammable gases (natural gas, for
example).
PRECAUTIONS FOR THE OPERATORS
Before proceeding with installation, commissioning or maintenance, operators must:
- examine the safety provisions applicable to the installation in which they must work;
- obtain the authorisations necessary for working when so required;
- use the necessary means of individual protection (helmet, goggles, etc.);
- ensure that the area in which they operate is fitted with the means of collective protection envisaged and with
the necessary safety indications.
HANDLING
The handling of the apparatus and of its components must only be carried out after ensuring that the lifting gear
is adequate for the loads to lift (lifting capacity and functionality). The apparatus must be handled using the lifting
points provided on the apparatus itself.
Motorised means must only be used by the persons in charge of them.
PACKING
The packing for trasportation of equipment and of relevant spare parts are designed and shaped to avoid damage to any
part during transportation, warehousing and handling activities. Therefore the equipment and spare parts shall be kept
into their packing until their installation in the final site. After packing is open, check that no damage occured to any
goods. If damage occured inform the supplier and keep packing for any verification.
INSTALLATION
If the installation of the apparatus requires the application of compression fittings in the field, these must be
installed following the instructions of the manufacturer of the fittings themselves. The choice of the fitting must
be compatible with the use specified for the apparatus and with the specifications of the system when envisaged.
PRECAUTIONS
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TECHNICAL MANUAL MT049
COMMISSIONING
Commissioning must be carried out by adequately trained personnel.
During the commissioning activities, the personnel not strictly necessary must be ordered away and the no-go
area must be properly signalled (signs, barriers, etc.).
Check that the settings of the apparatus are those requested; if necessary, reset them to the required values in
accordance with the procedures indicated in the manual.
When commissioning, the risks associated with any discharges into the atmosphere of flammable or noxious
gases must be assessed.
In installations in natural gas distribution networks, the risk of the formation of explosive mixtures (gas/air) inside
the piping must be considered.
CONFORMITY TO DIRECTIVE 97/23/EC (PED)
Pressure regulator Aperflux 851 are classified as fail open regulators according to the standard EN 334 therefore
they are pressure accessory according to directive 97/23/EC (PED).
The incorporated safety device monitor PM/819 (as well as the in-line monitor REFLUX 819) being classified as
fail close regulators according to the standard EN 334 is as safety accessory according PED, therefore it can be
used both as pressure accessory and safety accessory to PED. The regulator Aperflux 851 when incorporating
slam shut valve SB/82 or HB/97 with pressure switches for overpressure is a safety accessory according to PED,
therefore it can be used both as pressure accessory and safety accessory to PED.
The conformity with Directive PED of pressure regulator and relevant accessory bearing the CE marking requires
installation in systems with minimum requirements according to EN 12286
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TECHNICAL MANUAL MT049
INDEX
1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PAGE 9
1.1 MAIN FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.2 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.3 AR73 REGULATING VALVE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.4 SETTING SPRINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.0 INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.0 ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.1 RELIEF VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.1.1 DIRECT INSTALLATION IN THE LINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.1.2 INSTALLATION WITH ON/OFF VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.2 ACCELERATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.0 MODULARITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.1 INCORPORATED SB/82 SLAM-SHUT VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.2 INCORPORATED SB/82 SLAM-SHUT VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.2.1 SB/82 SLAM-SHUT OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.2.2 SB/82 SLAM-SHUT SETTING SPRINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3 INCORPORATED HB/97 SLAM-SHUT VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.3.1 HB/97 OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.3.2 HB/97 SLAM-SHUT SETTING SPRINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.4 MONITOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.4.1 PM/819 INCORPORATED MONITOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.4.2 IN-LINE MONITOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.5 SETTING SPRINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5.0 START UP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
5.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
5.2 GAS INPUT, CONTROL OF EXTERNAL TIGHTNESS AND SETTING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
5.3 COMISSIONING THE REGULATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
5.4 COMMISSIONING THE REGULATOR WITH INCORPORATED SB/82 SLAM-SHUT . . . . . . . . . . . . . . . . . . . . . . 34
5.5 COMMISSIONING THE REGULATOR WITH INCORPORATED PM/819 MONITOR AND
ACCELERATING VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
5.6 COMMISSIONING THE REGULATOR WITH REFLUX 819 IN-LINE MONITOR WITH INCORPORATED SB/82
SLUM-SHUT AND ACCELERATING VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.7 COMMISSIONING THE REGULATOR PLUS APERFLUX 851 IN-LINE MONITOR WITH INCORPORATED
SB/82 SLAM-SHUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
6.0 TROUBLE-SHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.1 APERFLUX 851 REGULATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.2 PM/819 MONITOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6.3 REGULATOR SB/82 SLAM-SHUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
7.0 MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
7.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
7.2 APERFLUX 851 REGULATOR MAINTENANCE PROCEDURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
7.3 PM/819 MONITOR MAINTENANCE PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
7.4 SLAM-SHUT DEVICE SB/82 MAINTENANCE PROCEDURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
8.0 FINAL OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
8.1 THIGHTNESS AND SETTING CHECKS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
8.2 START UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
9.0 WEIGHT OF THE COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
9.1 WEIGHT OF THE COMPONENTS IN KG. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
10.0 LIST OF RECOMMENDED SPARES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
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TECHNICAL MANUAL MT049
This manual proposes to provide the essential information for the installation, start-up, disassembly, reassembly
and maintenance of the Aperflux 851 regulators.
It is also appropriate, however, to provide a brief illustration of the main features of the regulator and of its
components.
1.1 MAIN FEATURES
The Aperflux 851 pressure regulator is a regulator of the piloted type for medium and high pressures.
The Aperflux 851 is a fail open type regulator and therefore opens in the event of:
- rupture of the main diaphragm;
- rupture of the pilot diaphragm/s;
- rupture of the pilot gasket;
- pilot circuit supply failure.
The main features of this regulator are:
- design pressure: up to 100 bar;
- design temperature: -20 °C to +60 °C;
- environmental temperature: -20 °C to +60 °C;
- range of the inlet pressure bpe: 1 to 80 bar;
- possible regulation range Wh: 0.6 to 74 bar (on the basis of the pilot installed);
- minimum differential pressure: 0.5 bar;
- precision class AC= up to 1.5;
- closing pressure class SG: up to 2.5.
1.2 OPERATION (FIG. 1)
In the absence of pressure, the main diaphragm 1 is maintained in the closed position by the spring 2 and rests
on the seat of the valve 3 with grill 4. The seal is guaranteed by the contact between the valve seat 3 and the
diaphragm 1.
In normal working conditions, the following forces act on the diaphragm 1:
- downwards: the load of the spring 2, the thrust deriving from the control pressure Pc in the control chamber A
and the weight of the mobile assembly;
- upwards: the thrusts deriving from the upstream pressure Pe and downstream pressure Pa and the remaining
dynamic components.
The control pressure Pc is obtained by drawing gas at the pressure Pe directly upstream from the diaphragm 1;
the gas is filtered by the filter 6 incorporated in the AR73 flow regulating valve. The pressure Pc is governed by
the pilot which regulates its value. Regulation is obtained from the comparison of the load of the setting spring
8 and the thrust on the diaphragm 12 deriving from the downstream pressure.
If during operation, for example, there is a drop in the downstream pressure Pa below the set point (as a result of
an increase in the flow demand or of a reduction of the upstream pressure) a state of imbalance of the mobile
assembly 11 is created and leads to an increase in the opening of the obturator 7 and therefore a reduction of the
control pressure Pc.
As a result, the diaphragm 1 moves upwards increasing the opening of the regulator until the downstream
pressure reaches the set point again.
On the other hand, when the downstream pressure rises beyond the set point (as a result of a reduction in the
demand or with the increase in the upstream pressure), the obturator 7 closes and therefore the pressure Pc
reaches the value of the upstream pressure Pe. In these conditions, the diaphragm 1 goes to the closed position.
In normal working conditions, the obturator 7 is positioned in such a way that the pressure Pc above the
diaphragm 1 is such as to maintain the downstream pressure around the selected value.
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1.0 INTRODUCTION
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TECHNICAL MANUAL MT049
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Fig. 1
Connections to be made
by the customer Ref. No. for the connections
3
7
3
7
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TECHNICAL MANUAL MT049
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302/A PILOT
Fig. 2A
vent
vent
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TECHNICAL MANUAL MT049
12
304/A PILOT
Fig. 2B
vent
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TECHNICAL MANUAL MT049
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1.3 AR73 REGULATING VALVE
The AR73 regulating valve is an adjustable flow regulation device. Its function is to adjust and differentiate the
regulator's response times so as to optimize its operation.
Small openings of the valve result in a greater regulating precision of the regulator, but also in a greater sensitivity
to instability phenomena (pumping); the opposite is true in the case of larger openings.
The opening is varied by turning the pin 4 with the reference mark which can be read on the graduated scale on
the front of the valve (fig. 3).
The positions 0 and 8 on the scale indicate the minimum and maximum valve openings respectively. To pass from
one valve opening position to another, the pin can be turned clockwise or anticlockwise indifferently; the two
graduated scales on the plate are in fact perfectly equivalent.
Fig. 3
Fig. 3a)
Complete opening
Reference notch
Fig. 3b)
Partial opening
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TECHNICAL MANUAL MT049
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1.4 SETTING SPRINGS
The Aperflux 851 regulator uses the 302/A, 304/A, 305/A and 307/A pilots. The regulation range of the different
pilots is given in the tables below.
Tab. 2 304/A Pilot setting springs
Code Colour De Lo d i it Setting range in bar
2702290 RED 5.5 8.5 10.5 7 ÷12
2702460 GREEN 6 8.25 10.25 10 ÷17
2702660 BLACK 35 100 6.5 8.25 10.25 15 ÷25
2702820 BLUE 7 7 9 20 ÷35
2703045 BROWN 7.5 7.5 9.5 30 ÷43
Tab. 3 305/A Pilot setting springs
Code Colour De Lo d i it Setting range in bar
2702820 BLUE 7 7 9 20 ÷35
2703045 BROWN 7.5 7.5 9.5 30 ÷43
2703224 GREY
35 100
8 7.5 9.5 40 ÷60
Tab. 4 307/A Pilot setting springs
Code Colour De Lo d i it Setting range in bar
2703224 GREY 35 100 8 7.5 9.5 41 ÷74
The operating principle of the pilot has already been briefly illustrated in par. 1.2. Variation of the setting is obtained
by turning the adjustment screw 10 (fig. 1). Clockwise rotation leads to an increase in the regulated pressure while
anticlockwise rotation leads to a decrease. When the desired setting has been reached, the adjustment screw can
be blocked by means of the provided nut 9.
De = Øexternal diameter d=Øwire diameter i = active coils Lo = Lenght it = total coils
Tab. 1 302/A Pilot setting springs
Code Colour De Lo d i it Setting range in bar
2701541 WHITE 4 7.75 9.75 0.8 ÷1.3
2701800 YELLOW 4.5 8.25 10.25 1.2 ÷2.1
2702080 ORANGE 35 100 5 8.75 10.75 2 ÷3.3
2702290 RED 5.5 8.5 10.5 3 ÷4.8
2702460 GREEN 6 8.25 10.25 4.5 ÷7
2702660 BLACK 6.5 8.5 10.25 6 ÷9.5
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TECHNICAL MANUAL MT049
2.1 GENERAL
Pressure regulator does not require any supplementary upstream safety accessory for protection against
overpressure compared with its design pressure PS, when upstream reducing station is sized for a max
downstream incidental pressure MIPd ≤1,1 PS.
Before installing the regulator it is necessary to ensure that:
- the regulator can be inserted in the space provided and that subsequent maintenance operations will be
sufficiently practicable;
- the upstream and downstream piping is at the same level and capable of supporting the weight of the regulator;
- the inlet/outlet flanges of the piping are parallel;
- the inlet/outlet flanges of the regulator are clean and the regulator itself has not been subject to damage during
transport;
- the piping upstream has been cleaned to expel residual impurities such as welding scale, sand, paint residues,
water, etc.
The normally raccomended set-up is:
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2.0 INSTALLATION
Fig. 4 (Standard regulator)
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TECHNICAL MANUAL MT049
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Regulator
Regulator
Pilot discharge
Control pressure gauge
Control pressure gauge
Pilot discharge
Bleed cock
Sensing line
Sensing line
Bleed chock
On/Off valve
On/Off valve
TAB. 5 CONNECTING THE APPARATUSES
The connections between the apparatus and the main piping must be made using stainless steel pipe with
minimum internal diameter of 8 mm.
IN-LINE INSTALLATION
INSTALLATION AT RIGHT ANGELS
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TECHNICAL MANUAL MT049
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1and 2Connect to regulators heads
3and 4Connect to pilots
5and 6Connect to accelerator and slam-shut
The regulator must be installed in the line with the arrow on the body pointing in the gas flow direction.
It is indispensable for good regulation that the position of the downstream pressure take-offs and the speed of the
gas at the take-off point respect the values given in tables 5 and 6 (positioning) and 7 (speed).
The pressure regulator, when installed on a reducing station, shall be installed at least according to the
requirements of standard EN 12186.
All venting connections shall be connected as required by above mentioned standard.
The following is recommended so as to prevent the accumulation of impurities and condensate in the lines
of the pressure take-offs:
a) the lines themselves must slope down towards the downstream piping connectors with a slope of about 5-10%;
b) the connectors on the piping must always be welded on the top of the piping itself and there must be no burr
or inward protrusions in the hole in the piping.
NB.WE RECOMMEND NOT TO PUT ON/OFF VALVES ON THE IMPULSE TAKE-OFFS
TAB. 6 DETAIL OF MULTIPLE TAKE - OFF WITH OF THE IMPULSE TAKE - OFF REFERENCE NUMBERS
TAB. 7
The speed of the gas must not exceed the following values in the piping downstream from the regulator:
Vmax= 30 m/s for Pa > 5 bar
Vmax= 25 m/s for 0,5 < Pa < 5 bar
3.0 ACCESSORIES
3.1 RELIEF VALVE
The relief valve is a safety device which releases a certain quantity of gas to the exterior when the pressure at the
control point exceeds the set-point as a result of short-lasting events such as, for example, the very fast closing
of the on/off valves and/or overheating of the gas with zero flow rate demand. The release of the gas to the exterior
can, for example, delay or block intervention of the slam-shut valve for transitory reasons deriving from damage
to the regulator.
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TECHNICAL MANUAL MT049
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Fig. 5
Obviously the quantity of gas released depends on the extent of the overpressure with respect to the set-point. The
different models of relief valve available are all based on the same operating principle which is illustrated below with
reference to the valve VS/AM 56 (fig. 5).
It is based on the contrast between the thrust on the diaphragm 24 deriving from the pressure of the gas to being
controlled and the thrust from the setting spring 20. The weight of the mobile assembly, the static thrust and the
residual dynamic thrust on the obturator 4 also contribute to this contrast.
When the thrust deriving from the pressure of the gas exceeds that of the setting spring, the obturator 4 is raised
and a certain quantity of gas is released as a result.
As soon as the pressure drops below the set-point, the obturator returns to the closed position. Proceed as
indicated below to control and adjust intervention of the relief valve.
3.1.1 DIRECT INSTALLATION IN THE LINE (FIG. 6)
When the relief valve is fitted directly in the line, that is without inserting an on-off valve, proceed as follows:
1) Ensure that the downstream on-off valve V2 and the bleed cock 6 are closed.
2) Increase the pressure in the downstream section up to the value envisaged for intervention in one of the
following ways:
- if the spring fitted on the pilot permits it (see tables 1-2-3-4), increase the setting of the pilot itself until the
desired value is obtained;
- connect a controlled auxiliary pressure to the cock 6 and stabilize it at the desired value;
3) Check the intervention of the relief valve and adjust it if necessary by turning the adjustament plug 13
appropriately (clockwise to increase and anticlockwise to decrease).
Fig. 6
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TECHNICAL MANUAL MT049
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3.1.2 INSTALLATION WITH ON/OFF VALVE (FIG. 7)
1) Close the on-off valve 16.
2) Connect a controlled auxiliary pressure to the nipple 17 and increase it slowly up to the value envisaged for
intervention.
3) Check the intervention of the relief valve and adjust if necessary by turning the adjustament plug 13
appropriately (clockwise to increase and anticlockwise to decrease).
3.2 ACCELERATOR
An accelerator (fig. 8) is installed on the PM/819 icorporated monitor and on the REFLUX 819 regulator (use as
in-line monitor) to speed up their intervention in the event of failure of the active regulator (racommended when
used safety accessory according to Directive 97/23/EC “PED”).
On the basis of a pressure signal from downstream this device discharges the gas into the monitor's motorization
chamber into the atmosphere, thereby permitting rapid intervention. The set point of the accelerator must
obviously be higher than that of the monitor.
Setting is made by turning the adjustment screw 17, clockwise to increase the value, anticlockwise to reduce it.
M/A range of intervention Who: 0,3 to 43 bar
Fig. 8
vent
vent
Accelerator M/A
Fig. 7
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0
1
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8
7
6
5
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4.0 MODULARITY
The modular-type design of APERFLUX 851 series regulators means that it is also possible to feitner the
emergency monitor regulator PM/819 or it the slam-shut incorporated with the body itself even after the
installation of the regulator without any modifications.
4.1 INCORPORATED SB/82 SLAM-SHUT VALVE
When closing the slam shut incorporated into pressure regulator to be considered as safety accessory according
to Directive PED, cuts off the feeding of gas both to pressure regulator and to its pilot.
4.2 INCORPORATED SB/82 SLAM-SHUT VALVE
This is a device (fig. 9) which immediately blocks the gas flow if, following some kind of failure, the downstream
pressure reaches the set-point for its intervention, or is operated manually.
On the APERFLUX 851 regulator, it is possible to have the SB/82 slam-shut incorporated both with the service
regulator and on the one functioning as in-line monitor.
The main characteristics of the slam-shut device are:
•intervention with pressure increase and/or decrease;
•design pressure: 100 bar for all the components;
•intervention accuracy (AG): ± 1% of the pressure set-point for pressure increases; ± 5% for pressure drops;
•manual resetting with internal by-pass operated by the resetting lever.
Fig. 9
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