Samson 3241-1-Gas Service manual

Translation of original instructions
EB 8020 EN
Automatic Shut-off Valves for Gases
Type3241-1-Gas and Type3241-7-Gas
Valve classD
Edition February 2020
Type3241‑7‑Gas with Type3963 Solenoid Valve and Type3730 Positioner

Note on these mounting and operating instructions
These mounting and operating instructions assist you in mounting and operating the device
safely. The instructions are binding for handling SAMSON devices. The images shown in
these instructions are for illustration purposes only. The actual product may vary.
ÎFor the safe and proper use of these instructions, read them carefully and keep them for
later reference.
ÎIf you have any questions about these instructions, contact SAMSON‘s After‑sales Service
Department ([e-mail]).
The mounting and operating instructions for the devices are included in
the scope of delivery. The latest documentation is available on our web‑
site at www.samsongroup.com > Service & Support > Downloads > Doc-
umentation.
Definition of signal words
Hazardous situations which, if not avoided,
will result in death or serious injury
Hazardous situations which, if not avoided,
could result in death or serious injury
Property damage message or malfunction
Additional information
Recommended action
DANGER
!
WARNING
!
NOTICE
!
Note
Tip
EB 8020 EN

Contents
EB 8020 EN
1 Safety instructions and measures ................................................................1-1
1.1 Notes on possible severe personal injury ......................................................1‑5
1.2 Notes on possible personal injury ................................................................1‑5
1.3 Notes on possible property damage.............................................................1‑7
1.4 Warnings on the device...............................................................................1‑8
2 Markings on the device ..............................................................................2-1
2.1 Nameplate for gas version of the control valve ..............................................2‑1
2.2 Valve nameplate .........................................................................................2‑2
2.3 Actuator nameplate.....................................................................................2‑3
2.4 DVGW register number...............................................................................2‑3
2.5 Material numbers........................................................................................2‑3
3 Design and principle of operation ...............................................................3-1
3.1 Versions .....................................................................................................3‑4
3.2 Additional ttings........................................................................................3‑4
3.3 Valve accessories ........................................................................................3‑5
3.4 Technical data ............................................................................................3‑5
4 Shipment and on-site transport ...................................................................4-1
4.1 Accepting the delivered goods .....................................................................4‑1
4.2 Removing the packaging from the valve........................................................4‑1
4.3 Transporting and lifting the valve..................................................................4‑1
4.3.1 Transporting the valve .................................................................................4‑2
4.3.2 Lifting the valve...........................................................................................4‑3
4.4 Storing the valve.........................................................................................4‑4
5 Installation.................................................................................................5-1
5.1 Installation conditions..................................................................................5‑1
5.2 Preparation for installation...........................................................................5‑2
5.3 Mounting the valve......................................................................................5‑3
5.3.1 Installing the valve into the pipeline ..............................................................5‑3
5.4 Testing the installed valve.............................................................................5‑4
5.4.1 Vent holes ..................................................................................................5‑5
5.4.2 Leak test.....................................................................................................5‑5
5.4.3 Travel motion..............................................................................................5‑5
5.4.4 Fail‑safe position.........................................................................................5‑5
5.4.5 Pressure test................................................................................................5‑6
6 Start-up .....................................................................................................6-1

Contents
EB 8020 EN
7 Operation..................................................................................................7-1
8 Malfunctions ..............................................................................................8-1
8.1 Troubleshooting ..........................................................................................8‑1
8.2 Emergency action .......................................................................................8‑2
9 Servicing....................................................................................................9-1
9.1 Periodic testing ...........................................................................................9‑3
9.2 Preparing the valve for service work .............................................................9‑6
9.3 Completing service work .............................................................................9‑6
9.4 Service work...............................................................................................9‑8
9.4.1 Replacing the gasket ...................................................................................9‑8
9.4.2 Cleaning the strainer...................................................................................9‑8
9.5 Ordering spare parts and operating supplies ................................................9‑9
10 Decommissioning .....................................................................................10-1
11 Removal ..................................................................................................11-1
11.1 Removing the valve from the pipeline..........................................................11‑1
11.2 Removing the actuator from the valve .........................................................11‑2
12 Repairs ....................................................................................................12-1
12.1 Returning devices to SAMSON ..................................................................12‑1
13 Disposal...................................................................................................13-1
14 Certicates...............................................................................................14-1
15 Annex......................................................................................................15-1
15.1 Tightening torques, lubricants and tools ......................................................15‑1
15.2 Spare parts ..............................................................................................15‑1
15.3 After‑sales service.....................................................................................15‑4

EB 8020 EN 1-1
Safety instructions and measures
1 Safety instructions and measures
Intended use
The SAMSON Type3241G Globe Valve in combination with the Type3271 or Type3277
Pneumatic Actuator and a solenoid valve is designed to regulate the ow rate, pressure or
temperature of fuel gases in gas‑consuming equipment. The valve, actuator and solenoid
valve are designed to operate under exactly dened conditions (e.g. operating pressure, pro‑
cess medium, temperature). Therefore, operators must ensure that the control valve is only
used in applications that meet the specications used for sizing the valve at the ordering
stage. In case operators intend to use the control valve in other applications or conditions
than specied, contact SAMSON.
SAMSON does not assume any liability for damage resulting from the failure to use the de‑
vice for its intended purpose or for damage caused by external forces or any other external
factors.
ÎRefer to the technical data and nameplate for limits and elds of application as well as
possible uses.
Reasonably foreseeable misuse
The control valve is not suitable for the following applications:
−Use outside the limits dened during sizing and by the technical data
−Use outside the limits dened by the valve accessories connected to the valve
Furthermore, the following activities do not comply with the intended use:
−Use of non‑original spare parts
−Performing service and repair work not described in these instructions
Qualications of operating personnel
The control valve must be mounted, started up, serviced and repaired by fully trained and
qualied personnel only; the accepted industry codes and practices are to be observed. Ac‑
cording to these mounting and operating instructions, trained personnel refers to individuals
who are able to judge the work they are assigned to and recognize possible hazards due to
their specialized training, their knowledge and experience as well as their knowledge of the
applicable standards (e.g. Gas Appliances Regulation (EU) 2016/426). Furthermore, the
operating personnel must be specially trained for the correct and safe handling of fuel gases
in gas‑consuming equipment.

1-2 EB 8020 EN
Safety instructions and measures
Explosion‑protected versions of this device must be operated only by personnel who has un‑
dergone special training or instructions or who is authorized to work on explosion‑protected
devices in hazardous areas.
Personal protective equipment
We recommend checking the hazards posed by the process medium being used (e.g.
uGESTIS (CLP) hazardous substances database). Depending on the process medium and/
or the activity, the protective equipment required includes:
−Protective clothing, gloves, eye protection and respiratory protection in applications with
hot, cold and/or corrosive media
−Wear hearing protection when working near the valve
−Hard hat
−Safety harness when working at height
−Safety footwear, ESD (electrostatic discharge) footwear, if necessary
ÎCheck with the plant operator for details on further protective equipment.
Revisions and other modications
Revisions, conversions or other modications of the product are not authorized by SAMSON.
They are performed at the user's own risk and may lead to safety hazards, for example. Fur‑
thermore, the product may no longer meet the requirements for its intended use.
Safety features
−Upon supply air or control signal failure, the valve moves to a certain fail‑safe position
(see 'Design and principle of operation' section). The fail‑safe action of the actuator is the
same as its direction of action and is specied on the nameplate of SAMSON actuators
(see associated actuator documentation).
−Valve classD: the safety control valves are tested according to DINEN161 (2013‑04).
In the event of a malfunction, the valves shut off the gas supply. They meet the strict leak‑
age requirements of Class D.
Warning against residual hazards
To avoid personal injury or property damage, plant operators and operating personnel must
prevent hazards that could be caused in the control valve by the process medium, the operat‑
ing pressure, the signal pressure or by moving parts by taking appropriate precautions. They
must observe all hazard statements, warning and caution notes in these mounting and oper‑
ating instructions.

EB 8020 EN 1-3
Safety instructions and measures
Hazards resulting from the special working conditions at the installation site of the valve must
be identied in a risk assessment and prevented through the corresponding safety instruc‑
tions drawn up by the operator.
ÎObserve safety measures for handling the device as well as re prevention and explosion
protection measures.
Responsibilities of the operator
The operator is responsible for proper operation and compliance with the safety regulations.
Operators are obliged to provide these mounting and operating instructions as well as the
referenced documents to the operating personnel and to instruct them in proper operation.
Furthermore, the operator must ensure that operating personnel or third persons are not ex‑
posed to any danger.
Responsibilities of operating personnel
Operating personnel must read and understand these mounting and operating instructions as
well as the referenced documents and observe the specied hazard statements, warnings
and caution notes. Furthermore, the operating personnel must be familiar with the applicable
health, safety and accident prevention regulations and comply with them.
Referenced standards and regulations
−The control valves comply with the requirements of the European Pressure Equipment Di‑
rective 2014/68/EU and the Machinery Directive 2006/42/EC. Valves with a CE mark‑
ing have a declaration of conformity which includes information about the applied con‑
formity assessment procedure. The 'Certicates' section contains this declaration of con‑
formity.
−Valve classD: the control valves meet the requirements of the previously valid European
Gas Appliance Directive 2009/142/EC and the currently valid Gas Appliances
Regulation (EU) 2016/426. The EC type examination certicate and EU declaration of
conformity are included in the 'Certicates' section.

1-4 EB 8020 EN
Safety instructions and measures
−The control valves meet the safety, construction and function requirements for automatic
shut‑off valves with gas burners, gas equipment and similar applications according to
DINEN161.
−According to the ignition risk assessment performed in accordance with EN13463‑
1:2009, section 5.2, the non‑electrical control valves do not have their own potential ig‑
nition source even in the rare incident of an operating fault. As a result, they do not fall
within the scope of Directive 2014/34/EU.
ÎFor connection to the equipotential bonding system, observe the requirements specied in
section6.4 of EN60079‑14 (VDE0165‑1).
Referenced documentation
The following documents apply in addition to these mounting and operating instructions:
−Mounting and operating instructions for the mounted actuator, e.g. uEB8310‑X for
Type3271 or Type3277 Pneumatic Actuator
−Mounting and operating instructions for mounted valve accessories (positioner, solenoid
valve etc.)
−uAB0100 for tools, tightening torques and lubricant

EB 8020 EN 1-5
Safety instructions and measures
1.1 Notes on possible severe personal injury
DANGER
!
Risk of bursting in pressure equipment.
Valves and pipelines are pressure equipment. Impermissible pressure or improper
opening can lead to valve components bursting.
ÎObserve the maximum permissible pressure for valve and plant.
ÎBefore starting any work on the control valve, depressurize all plant sections affect‑
ed as well as the valve.
ÎDrain the process medium from all the plant sections concerned as well as the
valve.
1.2 Notes on possible personal injury
WARNING
!
Risk of burn injuries due to hot or cold components and pipelines.
Depending on the process medium, valve components and pipelines may get very hot
or cold and cause burn injuries.
ÎAllow components and pipelines to cool down or heat up.
ÎWear protective clothing and safety gloves.
Risk of hearing loss or deafness due to loud noise.
The noise emissions depend on the valve version, plant facilities and process medium.
ÎWear hearing protection when working near the valve.
Risk of personal injury due to exhaust air being vented.
While the valve is operating, the actuator or valve accessories may vent during closed‑
loop control or when the valve opens or closes.
ÎInstall the control valve in such a way that vent holes are not located at eye level and
the actuator does not vent at eye level in the work position.
ÎUse suitable silencers and vent plugs.
ÎWear eye protection when working in close proximity to the control valve.

1-6 EB 8020 EN
Safety instructions and measures
WARNING
!
Crush hazard arising from moving parts.
The control valve contains moving parts (actuator and plug stem), which can injure
hands or ngers if inserted into the valve.
ÎDo not insert hands or nger into the yoke while the air supply is connected to the
actuator.
ÎBefore working on the control valve, disconnect and lock the pneumatic air supply
as well as the control signal.
ÎDo not impede the movement of the actuator and plug stem by inserting objects into
the yoke.
ÎBefore unblocking the actuator and plug stem after they have become blocked (e.g.
due to seizing up after remaining in the same position for a long time), release any
stored energy in the actuator (e.g. spring compression). See associated actuator
documentation.
Risk of personal injury due to preloaded springs.
Valves in combination with pneumatic actuators with preloaded springs are under ten‑
sion. These control valves with SAMSON pneumatic actuators can be identied by the
long bolts protruding from the bottom of the actuator.
ÎBefore starting any work on the actuator, relieve the compression from the preload‑
ed springs (see associated actuator documentation).
Risk of personal injury due to residual process medium in the valve.
While working on the valve, residual process medium can escape and, depending on
its properties, may lead to personal injury, e.g. (chemical) burns.
ÎIf possible, drain the process medium from all the plant sections affected and the
valve.
ÎWear protective clothing, safety gloves, respiratory protection and eye protection.

EB 8020 EN 1-7
Safety instructions and measures
WARNING
!
Risk of personal injury through incorrect operation, use or installation as a result of
information on the valve being illegible.
Over time, markings, labels and nameplates on the valve may become covered with dirt
or become illegible in some other way. As a result, hazards may go unnoticed and the
necessary instructions not followed. There is a risk of personal injury.
ÎKeep all relevant markings and inscriptions on the device in a constantly legible
state.
ÎImmediately renew damaged, missing or incorrect nameplates or labels.
1.3 Notes on possible property damage
NOTICE
!
Risk of valve damage due to contamination (e.g. solid particles) in the pipeline.
The plant operator is responsible for cleaning the pipelines in the plant.
ÎFlush the pipelines before start‑up.
Risk of valve damage due to unsuitable medium properties.
The valve is sized according to Gas Appliances Regulation (EU) 2016/426 (valve
classD) for fuel gases.
ÎOnly use the process medium specied for sizing the valve.
Risk of leakage and valve damage due to excessively high or low tightening
torques.
Observe the specied torques on tightening control valve components. Excessively
tightened torques lead to parts wearing out quicker. Parts that are too loose may cause
leakage.
ÎObserve the specied tightening torques (uAB0100).
Risk of valve damage due to the use of unsuitable tools.
Certain tools are required to work on the valve.
ÎOnly use tools approved by SAMSON (uAB0100).

1-8 EB 8020 EN
Safety instructions and measures
NOTICE
!
Risk of valve damage due to the use of unsuitable lubricants.
The lubricants to be used depend on the valve material. Unsuitable lubricants may cor‑
rode and damage the surface.
ÎOnly use lubricants approved by SAMSON (uAB0100).
Risk of contamination of the process medium through the use of unsuitable lubricants
and/or contaminated tools and components.
ÎKeep the valve and the tools used free from solvents and grease.
ÎMake sure that only suitable lubricants are used.
1.4 Warnings on the device
Warning Meaning of the warning Location on the device
Warning against moving parts
There is a risk of injury to hands or ngers through the
stroking movement of the actuator and plug stem if they
are inserted into the yoke while the air supply is con‑
nected to the actuator.

EB 8020 EN 2-1
Markings on the device
2 Markings on the device
2.1 Nameplate for gas version of the control valve
SAMSON AG
Weismüllerstraße 3
D-60314 Frankfurt/M
Vanne de réglage
Meßstelle
Repère
TAG No.
Auftrags-Nr.
Order No.
NOde commande
Control ValveStellventil
Type
DN Material Kvs
Cv Characteristic
Isolierteil
mm Insulating section
Pièce d‘isolement
lin. on-off
Mischventil
Vanne Mélangeuse
Mixing Valve
%
Verteilventil
Diverting Valve
Vanne de Distribution
Strömungsteiler
Flow divider
Répartiteur de flux
Hub
Travel
Course
stellitiert
stellited
stellité
weich dichtend
soft seated
PTFE élanchéité
PTFE
Graphite
Balg
Soufflet
Bellows
entlastet
balanced
équilibré
PTFE
Graphite
Sitz/Kegel
Seat/Plug
Siège/Clapet
Presse-étoupe
Stopfbuchse
Stuffing box
Stellantrieb
Actuator
Servo-moteur cm²
Federbereich
Spring range
Gamme du ressort
Feder schließt
Spring closes
Ressort ferme
öffnet
opensopens
ouvre
Max. Stelldruck 6 bar
Max. signal pressure 87 psi
Pression de commande max.
Stelldruckbereich
Signal pressure range
Plage de pression de commande bar Δp max. = bar p2 = 0
Made in Germany
Medium
Fluid
Fluide
°C
Betriebstemp. t1
Operating temp.
Temp. de service
bar
Betriebsdruck p1abs
Operating pressure
Pression de service
PN
bar
1234 5
6 7 89 10
10 10
1211 13
11 11
14
14
15
15 16
16 17 18
19 20 20 21
22 23 24
25 26 27 28
Fig.2-1: Nameplate for gas version
Item Inscription meaning
1Type
2Conguration ID
3 (empty)
4 Order number
5 Tag no.
6 Valve size:
DIN: DN · ANSI: NPS
7 Pressure rating:
DIN: PN · ANSI: CL
8 Material
9 Flow coefcient:
DIN: KVS · ANSI: CV
10 Characteristic:
%: equal percentage ·
lin: linear · on‑off: on/
off service
Item Inscription meaning
11 Seat‑plug seal:
Material
Stellite® facing
Soft seal with PTFE
12 Valve travel in mm
13 Insulating section
14 Mixing or diverting
valve
15 Packing:
PTFE
Graphite
16 Pressure balancing:
PTFE
Graphite
17 Bellows material
18 Flow divider
19 Actuator area in cm²
Item Inscription meaning
20 Direction of action
Fail‑close
Fail‑open
21 Max. signal pressure in
bar
22 Bench range in bar
23 Signal pressure range in
bar
24 Max. differential
pressure in bar
25 Operating pressure in
bar
26 Operating temperature
in °C
27 Process medium
28 (empty)
The nameplate for the gas version (210) is afxed to the actuator (see Fig.2‑4).

2-2 EB 8020 EN
Markings on the device
2.2 Valve nameplate
22
21
20 19
1817
16
151413121110
8
7
6
5
4
2
1
Fig.2-2: Inscriptions on the valve nameplate
Fig.2-1 and the inscription table list all pos-
sible characteristics and options that may
appear on a valve nameplate. Only the in-
scriptions relevant to the ordered
Type3241G Valve actually appear on the
nameplate.
Note
Item Inscription meaning
1 Data Matrix code
2Type designation
4 Material
5 Month and year of manufacture
6 Valve size:
DIN: DN · ANSI: NPS · JIS: DN
7 Pressure rating:
DIN: PN · ANSI: CL · JIS: K
8 Order number/item
10 Flow coefcient:
DIN: KVS · ANSI: CV
11 Characteristic:
%: equal percentage · LIN: linear
mod-lin: modied linear
NO/NC: on/off service
12 Seat‑plug seal:
ME: metal · HA: carbide metal ·
ST: metal base material with Stellite® facing
KE: ceramic · PT: PTFE soft seal · PK: PEEK
soft seal
13 Seat code (trim material): on request
14 Pressure balancing:
DIN: D · ANSI/JIS: B
Version:
M: mixing valve · V: ow‑diverting valve
Item Inscription meaning
15 Noise reduction:
1:ow divider(ST)1 · 2:ST2 · 3:ST3
1/PSA:ST1 standard and integrated in
seat for PSA valve
AC-1/AC-2/AC-3/AC-5:AC trim, versions
1 to 5 · LK: perforated plug · LK1/LK2/
LK3:perforated plug with ow divider ST1
to ST3 · MHC1:multi‑hole cage
CC1:Combi Cage · ZT1:Zero Travel
16 Country of origin
17 PSA version:
PSA
18 Cage/seat style:
CC: clamped cage, clamped seat
SF: suspended cage, anged seat
19 CE marking
20 ID of the notied body
PED: Pressure Equipment Directive
G1/G2: gases and vapors
Fluid group1= hazardous
Fluid group2= other
L1: liquids
Fluid group1= hazardous
Fluid group2= other
I/II/III: Category 1 to 3
21 Serial number
22 NE53 (NAMUR Recommendation)

EB 8020 EN 2-3
Markings on the device
The valve nameplate (80) is afxed to the
ange (see Fig.2‑4).
2.3 Actuator nameplate
See associated actuator documentation.
The actuator nameplate (A100) is stuck on
the diaphragm casing (see Fig.2‑4).
2.4 DVGW register number
Typ 3241-G
DVGW-PIN
Klasse D, p zul.
Zul. Außentemp. –29…+60°C
0085
Fig.2-3: DVGW register number
The plate with the DVGW register number
(212) is afxed to the bellows seal (see
Fig.2‑4).
2.5 Material numbers
The seat and plug of the valves have an item
number written on them. Specifying this item
number, you can contact us to nd out which
material is used. Additionally, a seat code is
used to identify the trim material. This seat
code is specied on the valve nameplate.
210
80
A100
212
Fig.2-4: Markings on the control valve

2-4 EB 8020 EN

EB 8020 EN 3-1
Design and principle of operation
3 Design and principle of oper-
ation
See Fig.3‑1
The seat (4) and plug with plug stem (5) are
installed in the body (1). The plug stem is
screwed to the plug stem with bellows seal
(37). The plug stem is sealed by the metal
bellows and the packing (15). The stem con‑
nector clamps (A26/27) connect the actua‑
tor stem (A7) of the mounted actuator.
The bellows seal (22) is tted with a test con‑
nection (42). It can be used to monitor the
sealing ability of the bellows.
A strainer installed upstream of the valve
body. It prevents solid particles in the pro‑
cess medium from damaging the valve. The
strainer is not required when a central strain‑
er facility is installed.
The springs in the pneumatic actuator are lo‑
cated either above or below the diaphragm
depending on the selected fail‑safe action. A
change in the signal pressure acting on the
diaphragm causes the plug to move. The ac‑
tuator size is determined by the diaphragm
area.
The process medium ows through the strain‑
er and the valve in the direction indicated by
the arrow. A rise in signal pressure causes
the force acting on the diaphragm in the ac‑
tuator to increase. The springs are com‑
pressed. Depending on the selected direction
of action, the actuator stem retracts or ex‑
tends. As a result, the plug position in the
seat changes and determines the ow rate
through the valve.
The signal pressure pst is applied to the pilot
valve whose coil is connected to the safety
interlock circuit (switch 14, Fig.3‑2 and
Fig.3‑3). During operation, the coil is ener‑
gized and the signal pressure pst acts on the
diaphragm. In the event of a malfunction,
the pilot valve is activated and the pressure
acting on the diaphragm is relieved, causing
the control valve to quickly close.

3-2 EB 8020 EN
Design and principle of operation
Pst
4
5
1
22
37
14
2
10
9
842
15
17
A26/27
A7 Pilot valve
Strainer
1 Body
2Flange
4 Seat
5 Plug (with plug stem)
8 Threaded bushing (packing nut)
9 Stem connector nut
10 Lock nut
14 Body nut
15 Packing
17 Body gasket
22 Bellows seal
37 Plug stem with metal bellows
42 Test connection
A7 Actuator stem
A26/27 Stem connector clamps
Fig.3-1: Type3241-1-Gas Automatic Shut-off Valve

EB 8020 EN 3-3
Design and principle of operation
Voltage
Pst
2
13
11
14
11 Pilot valve
13 Positioner
14 Switch for safety
interlock circuit
Fig.3-2: Functional diagram showing version without positioner
Voltage
Pst
2
1
13
3
11
14
Fig.3-3: Functional diagram showing version with positioner

3-4 EB 8020 EN
Design and principle of operation
Fail-safe action
The fail‑safe position depends on the actua‑
tor used. See associated actuator documen‑
tation.
Depending on how the compression springs
are arranged in the SAMSON Type3271
and Type3277 Pneumatic Actuator, the
valve has one of two different fail‑safe posi‑
tions:
−Actuator stem extends (FA)
When the signal pressure is reduced or
the air supply fails, the springs move the
actuator stem downward and close the
valve. The valve opens when the signal
pressure is increased enough to over‑
come the force exerted by the springs.
−Actuator stem retracts (FE)
When the signal pressure is reduced or
the air supply fails, the springs move the
actuator stem upwards and open the
valve. The valve closes when the signal
pressure is increased enough to over‑
come the force exerted by the springs.
The "actuator stem extends" direction of ac-
tion is only permitted for the Type3241G
Valve in valve classD (see Table 3-3).
3.1 Versions
Actuators
ÎTo select a suitable actuator, see Table
3‑3 (valve classD).
3.2 Additional ttings
Strainer
Install a strainer or a central strainer facility
upstream of the valve body. It prevents solid
particles in the process medium from dam‑
aging the valve.
For special versions made of A216WCC or
A351CF8M in Class300: as a DIN version
of the Type2NI Strainer is only available, a
central strainer facility must be installed
when an ANSI version is used.
Insulation
Control valves can be insulated to reduce
heat energy transfer.
Refer to the instructions in the 'Installation'
section.
Test connection
Versions with bellows seal tted with a test
connection (G
1
/
8
) at the top ange allow the
sealing ability of the bellows to be moni‑
tored.
Safety guard
For operating conditions that require in‑
creased safety (e.g. in cases where the valve
is freely accessible to untrained staff), a safe‑
ty guard must be installed to rule out a crush
hazard arising from moving parts (actuator
and plug stem). Plant operators are responsi‑
ble for deciding whether a guard is to be
used. The decision is based on the risk posed
by the plant and its operating conditions.
Note
Note