Samson 2335 Service manual

Translation of original instructions
EB 2552-2 EN
Type2335 Excess Pressure Valve with Pilot Valve
Self-operated Regulators
Edition July 2021

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 2552-2 EN
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
([e-mail]).
Documents relating to the device, such as the mounting and operating
instructions, are available on our website at www.samsongroup.com >
Service & Support > Downloads > Documentation.

Contents
EB 2552-2 EN
1 General safety instructions.............................................................................4
2 Process medium and scope of application.......................................................5
2.1 Transportation and storage.............................................................................5
3 Design and principle of operation ..................................................................6
4 Installation....................................................................................................9
4.1 Notes on installation ......................................................................................9
4.2 Strainers .....................................................................................................10
4.3 Shut-off valve...............................................................................................10
4.4 Pressure gauge ............................................................................................10
5 Operation...................................................................................................12
5.1 Start-up.......................................................................................................12
5.2 Pressure test.................................................................................................12
5.3 Steam applications.......................................................................................13
5.4 Adjusting the set point..................................................................................13
5.5 Decommissioning.........................................................................................13
6 Maintenance ...............................................................................................14
7 Nameplate..................................................................................................18
8 Technical data .............................................................................................19
9 Dimensions .................................................................................................21
10 After-sales service .......................................................................................23

4 EB 2552-2 EN
General safety instructions
1 General safety instructions
− The device must be mounted, started up or serviced by fully trained and
qualiedpersonnelonly;theacceptedindustrycodesandpracticesareto
be observed. Make sure employees or third parties are not exposed to any
danger.
− All safety instructions and warnings given in these mounting and operating
instructions, particularly those concerning installation, start-up, and mainte-
nance, must be strictly observed.
− According 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 dangers due to their specialized training, their
knowledge and experience as well as their knowledge of the applicable
standards.
− The devices comply with the requirements of the European Pressure
Equipment Directive 2014/68/EU. Devices with a CE marking have an EU
declaration of conformity, which includes information about the applied
conformity assessment procedure. This EU declaration of conformity can be
provided on request.
− To ensure appropriate use, only use the regulator in applications where the
operatingpressureandtemperaturesdonotexceedthespecicationsused
for sizing the regulator at the ordering stage.
− The manufacturer does not assume any responsibility for damage caused by
external forces or any other external factors.
− Any hazards that could be caused in the valve by the process medium, op-
erating pressure or by moving parts are to be prevented by taking appropri-
ate precautions.
− Proper transport, storage, installation, operation and maintenance are as-
sumed.
!

EB 2552-2 EN 5
Process medium and scope of application
2 Process medium and scope of
application
Pressure regulators for set points from 2 to
28bar·ValvesizesDN65to400·Pressure
ratingPN16to40·Suitableforliquids,
gasesandvaporsupto350°C
The differential pressure across the regulator
is used as auxiliary energy to operate the
valve. To open the regulator, this pressure
must be at least as high as the minimum dif-
ferentialpressure∆pminspeciedinTable1.
The attached pilot valve (acting as an excess
pressure valve) determines the function of the
regulator.
Risk of uncontrolled excess pressure in the
plant.
Risk of bursting
If necessary, a suitable overpressure
protection must be installed on site in the
plant section.
WARNING
!
2.1 Transportation and storage
The device must be carefully handled, trans-
ported and stored. Protect the regulator
againstadverseinuences,suchasdirt,
moisture or temperature outside the ambient
temperature range.
Do not remove the protective caps from the
valve ports until immediately before install-
ing the valve into the pipeline.
When regulators are too heavy to be lifted
by hand, fasten the lifting equipment to a
suitable place on the valve body.
Do not attach lifting slings or lifting equip-
ment to mounting parts, such as control
line, pilot valve etc.
The valve can fall or mounting parts may be
damaged.
Securely fasten slings or lifting equipment to
the valve body and secure against slipping.
WARNING
!

6 EB 2552-2 EN
Design and principle of operation
3 Design and principle of oper-
ation
See Fig.1 and Fig.2.
Themediumowsthroughtheglobevalve
(1) in the direction indicated by the arrow.
Thepositionoftheplugdeterminestheow
rate across the area released between plug
(3) and seat (2). The travel position of the pi-
lot valve (5) determines the pressure condi-
tions across the valve.
The forces created by the upstream pressure
p1acting on the plug surface and by the
control pressure pSacting on the balancing
bellows (4) or balancing diaphragm (11)
and the force of set point spring (3.1) are
compared.
IntheType2335ExcessPressureValve,the
rising upstream pressure p1causes the main
valve to open. Together with the pilot valve,
theVenturinozzle(8)(thexedrestriction
(6) and needle valve (9) in the version for
steam) create the control pressure pS.
When the pilot valve is closed, the valve is
fully balanced. The control pressure pSbe-
tweenthepilotvalveandVenturinozzleact-
ing on the outside of the balancing bellows
(4) or balancing diaphragm (11) and the
upstream pressure p1balance each other out
(pS= p1). The set point spring below the plug
closes the valve.
When the pilot valve opens, the control pres-
sure pSfalls, causing the differential pressure
at the balancing bellows or balancing dia-
phragm to increase. The force acting on the
plug surface opposes the force of the springs
and the valve opens.
To ensure proper functioning, the minimum
differentialpressure∆pmin must be available
asspecieddependingontheeldofappli-
cation.
The regulator version for steam is only avail-
able with valves balanced by a bellows. This
version has a compensation chamber (10)
alreadyttedinthecontrolline.Theneedle
valve (9) is open and lead-sealed.
Beforestart-up,llthecompensationcham-
berwithwateratthetoplleropening.
Table1: Minimum differential pressure ∆pmin
Valve size DN65 DN80 DN100 DN125 DN150 DN200 DN250 DN300 DN400
Minimum differential
pressure∆pmin
Valvebalancedby
a bellows for steam
applications 0.2bar(640cm²actuator)
0.4bar(320cm²actuator)
1.9bar 2.0bar 1.4bar 1.4bar – –
Valvebalancedby
a bellows for air/
water
1.0bar 1.0bar 0.7bar 0.7bar – –
Valvebalancedby
a diaphragm –0.8bar 0.8bar 0.4bar 0.4bar 0.5bar 0.3bar

EB 2552-2 EN 7
Design and principle of operation
Type2335ExcessPressureValve·Type2422Valvebalanced by a bellows·DN125 to 250
1
2
3
3.1
4
5
7
10
p1p2
8
9
5.1
Type 2422 as main valve balanced by a bellows
Bottom section
with bellows
Pilot valve
pS
Versionsuitableforvapors
7
8
5.1
1
2
3
4
5
Pilot valve
Bottom section
with bellows
pS
Versionsuitableforliquidsandgases
1 Globe valve (main valve)
2 Seat
3 Plug with plug stem
3.1 Set point spring
4 Balancing bellows
5 Pilot valve
5.1 Control line for pilot valve
6Venturinozzle(forgasesand
liquids)
7 Strainer
8 Fixed restriction (version for steam)
9 Needle valve (version for steam)
10 Compensation chamber (only for steam or
mediumtemperaturesabove150°C)
pSControl pressure
p1Upstream pressure
p2Downstream pressure
Fig.1: Functional diagram of valve balanced by a bellows

8 EB 2552-2 EN
Design and principle of operation
Type2335ExcessPressureValve·Type2422Valve,balanced by a diaphragm·DN125to400
6
7
1233.1 11
p1p
2
5.1
5
Diaphragm section
Type2422 as main valve, balanced by a diaphragm
pS
Pilot valve
1Valvebody(mainvalve)
2 Seat
3 Plug with plug stem
3.1 Set point spring
5 Pilot valve
5.1 Control line for pilot valve
6Venturinozzle
7 Strainer
11 Balancing diaphragm
pSControl pressure
p1Upstream pressure
p2Downstream pressure
Fig.2: Functional diagram of valve balanced by a diaphragm

EB 2552-2 EN 9
Installation
4 Installation
See Fig.3.
Select the installation location making sure
that the regulator is installed at a distance of
at least six times the valve size (DN) away
frompipettingsorinstrumentsthatcause
owturbulence(e.g.pipebends,manifolds,
pressure measuring points or other valves).
Theycanchangetheowconditionswhich
may lead to an instable control process es-
pecially in applications with gases, air or
steam.
Contact SAMSON to obtain the
TV-SK17041documentationwhichcontains
more details on installation requirements.
4.1 Notes on installation
Install the ready-assembled regulator in hori-
zontal pipelines.
− Flush and clean the pipeline thoroughly
before installing the regulator.
Otherwise, impurities in the pipeline may
impair the proper functioning of the
valve, above all the tight shut-off.
− Thedirectionofowmustmatchthedi-
rection indicated by the arrow on the
body.
− Install the regulator free of stress. If nec-
essary, support the pipeline near to the
connectinganges.Donotattachsup-
ports directly to the valve or actuator.
− Install a strainer upstream of the regula-
tor.
− Protect the regulator from icing up when
controlling media that can freeze. If nec-
essary, depressurize and drain the regu-
lator and remove it from the pipeline
while the plant is shut down.
The side on which the operating elements
(hook-up of the pilot valve) are located var-
ies depending on whether a valve balanced
by a bellows or a diaphragm is used.
Mounting orientation
Observetheowdirection.
Valve balanced by a bellows
− Bellows including housing
suspended downward.
Valve balanced by a diaphragm
− Balancing diaphragm (diaphragm sec-
tion) pointing upward
Insulation ·Toinsulatecoldsystems,we
recommendrstllingtheplantandcarefully
rinsingit(seesection5.1).Theregulator
must not be insulated until the set point is
adjusted.
− Start up the plant and adjust the set
point. Shut down the plant again and let
it heat up until the condensation water
has dried off.
− Afterwards, insulate the regulator and
pipes conveying the process medium us-
ing insulation material with a water va-
por barrier. If the pilot valve has a
spring, it must must be protected by a
sleeve to allow it to move. The
spring-loaded actuator stem must not
touch the insulation.
Note


10 EB 2552-2 EN
Installation
Thermal insulation
Do not insulate the pilot valve as well in ap-
plications with medium temperatures above
80°C.
Pipeline routing
The inlet and outlet lengths vary depending
on several variables and process conditions
and are intended as recommendations. Con-
tactSAMSONifthelengthsaresignicantly
shorter than the recommended lengths.
To ensure that the regulator functions proper-
ly, proceed as follows:
ÎObserve the inlet and outlet lengths (see
Table2).ContactSAMSONiftheregula-
tor conditions or state of the medium
process deviate.
ÎInstall the regulator free of stress and
with the least amount of vibrations as
possible.
ÎFor media with a tendency to conden-
sate, install the pipeline with a slight
downward slope on both sides so that
the condensate can drain properly. If the
pipeline upstream and downstream of
the regulator run vertically upwards, an
automatic drainage is required.
ÎInstalltheregulatorallowingsufcient
space to remove the actuator and valve
or to perform service work on them.
Pressure testing of the plant·Thepressure
must not exceed the maximum permissible
pressure of the regulator and plant on testing
Note
the pressure of the plant when the regulator
is already installed. An excessive test pres-
sure can damage the balancing bellows or
diaphragm. If necessary, remove the regula-
tor from the pipeline or isolate the regulator
in the pipeline and install a bypass.
4.2 Strainers
Installastrainer(e.g.SAMSONType1/
Type2)upstreamoftheexcesspressure
valve.
− Thedirectionofowmustcorrespondto
the arrow on the body.
− Do not use the strainer to permanently
ltertheprocessmedium.
− Thelterelementmustbeinstalledto
hang downwards or sideways for appli-
cations with steam.
Remember to leave enough space to remove
the lter element.
4.3 Shut-off valve
Install a hand-operated shut-off valve both
upstream of the strainer and downstream of
the regulator. This allows the plant to be shut
down for cleaning and maintenance, and
when the plant is not used for longer periods
of time.
4.4 Pressure gauge
Install a pressure gauge both upstream and
downstream of the regulator to monitor the
pressures prevailing in the plant.
Tip