Samson 2371 Series Service manual

Translation of original instructions
EB 2640 EN
Edition April 2020
Type 2371-11 Pressure Reducing Valve
Manual set point adjustment
Type2371-10 Pressure Reducing Valve
Pneumatic set point adjustment
Type2371-10 Pressure Regulator·Pneumatic set point adjustment
Type2371-11 Pressure Regulator·Manual set point adjustment
Series 2371 Pressure Reducing Valve for the Food and Pharmaceutical
Industries

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.
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 website
at www.samsongroup.com > Service & Support > Downloads > Docu-
mentation.
Denition 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
2 EB 2640 EN

Contents
EB 2640 EN 3
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..................................................................................................10
4.1 Mounting orientation....................................................................................10
4.2 Shut-off valve and pressure gauge.................................................................10
4.3 Safety valve.................................................................................................11
4.4 Leakage line connection ...............................................................................11
5 Operation...................................................................................................11
5.1 Start-up.......................................................................................................11
5.2 Adjusting the set point..................................................................................11
5.2.1 Setpoint·Type2371-11..............................................................................12
5.2.2 Setpoint·Type2371-10..............................................................................14
5.3 Operation ...................................................................................................14
5.4 Decommissioning.........................................................................................14
6 Cleaning and maintenance .........................................................................15
6.1 Cleaning .....................................................................................................15
6.2 Maintenance·Replacingparts......................................................................19
6.3 Replacing the plug .......................................................................................19
6.4 Replacing the diaphragm unit .......................................................................21
6.5 Replacing the two diaphragms......................................................................22
6.5.1 Replacing the set point springs......................................................................24
7 After-sales service .......................................................................................24
8 Nameplate..................................................................................................25
9 Technical data .............................................................................................26
10 Dimensions .................................................................................................27

4 EB 2640 EN
General safety instructions
1 General safety instructions
−The regulator is to 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 persons 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.
−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 regulator by the process medium,
operating pressure or by moving parts are to be prevented by taking appro-
priate precautions.
−Proper transport, storage, installation, operation, and maintenance are as-
sumed.
Non-electric actuators and control valve versions do not have their own potential
ignition source according to the ignition risk assessment stipulated in EN13463-
1: 2009, section 5.2, even in the rare incident of an operating fault. Therefore,
they do not fall within the scope of Directive 94/9/EC. For connection to the equi-
potential bonding system, observe the requirements specied in section 6.3 of
EN60079-14: 2014-10 (VDE0165 Part 1).
Note

EB 2640 EN 5
Process medium and scope of application
2 Process medium and scope
of application
Pressure regulators for the food and pharma-
ceutical industries for liquids and gases in the
temperaturerangefrom0to160°C/32to
320°F·K
VS
0.63to16/C
V
0.75to20·Valve
sizeDN15to50/NPS½to2.
For controlling the output pressure p2to the
adjusted set point. The valve closes when the
downstream pressure rises.
The Type2371-10/-11 Regulators are not
designed as safety valves. Exceeding the
maximum pressure (10bar/150psi) of the
regulator may cause it to burst.
If necessary, a suitable overpressure
protection must be installed on site in the
plant section.
The Type2371-10 and Type2371-11
Regulators are shut-off devices that do not
guarantee absolute tight shut-off. As a result,
they may have leakage when closed
(leakage class according to IEC60534-4 or
ANSI/FCI 70-2, see section9 on
page26). As a result, the output pressure
p2can rise to the same level as the input
pressure p1in a plant which does not have
its own consumption.
WARNING
!
Note
2.1 Transportation and storage
The regulators must be carefully handled,
transported and stored. During storage and
transportation before installation: Protect the
regulatorsagainstadverseinuences,suchas
dirt, moisture or temperatures outside the op-
erating temperature range.

6 EB 2640 EN
Design and principle of operation
3 Design and principle of op-
eration
TheType2371-10andType2371-11Pres-
sure Reducing Valves consist mainly of a sin-
gle-seated angle valve with operating dia-
phragm and actuator housing.
ThesetpointoftheType2371-10isadjusted
pneumatically by an external air supply, e.g.
compressed air.
The set point of Type 2371-11 is adjusted
manually by tensioning the set point spring.
Themediumowsthroughthevalvebody(1)
in the direction indicated by the arrow. The
positionoftheplug(3)determinestheow
rate across the area released between plug
and valve seat (2). The valve closes when the
downstream pressure p2rises above the ad-
justed set point. The resulting output pressure
p2dependsontheowrate.
Any medium escaping from the test connec-
tion (11) indicates that the operating dia-
phragm (4) may be leaking or the diaphragm
has ruptured. The test connection of
Type2371-10isconnectedtoaexiblepipe
elbow to discharge any medium escaping
(leakage line connection).
Type2371-11·Version with manual set
point adjustment (seealsosection5.2on
page11)
In the idle state, the valve is kept open by the
set point springs (7). The valve closes when
the output pressure p2acting on the dia-
phragm (4) and the resulting force exceed the
force of the springs.
The set point is adjusted by an Allen key
(8mm),whichisinsertedthroughtheadjust-
ment opening (6.1) on top of the housing on-
to the set point screw (6). The blanking plug
mustrst beremoved.If necessary,theset
point screw can be secured by the locking
screw (12) in the upper plug section to prevent
the set point screw from loosening due to vi-
brations, causing the set point to change.
The washer (15) serves as a bottom end stop
to protect the diaphragm from overload and
to prevent parts from falling apart inadver-
tently while the regulator is being dismantled.
Turning the set point screw clockwise causes
the spring plate (7.1) to move upwards and
increases the spring force and the set point.
Turning the set point screw counterclockwise
relieves the spring tension and reduces the set
point.
Type2371-10·Version with pneumatic set
point adjustment (seealsosection5.2on
page11)
In the idle state, the valve is kept open by the
set point pressure pc(compressed air) applied
as the control pressure.
When the force created by the output pressure
p
2
acting on the diaphragm exceeds the force
resulting from the set point pressure pc, the
plug (3) moves towards the seat (2), closing
the passage. In this case, the ratio between p
1
and pCis not necessarily 1:1.
As the output pressure p
2
drops, the resulting
force reduces again. The valve is opened
again when the pressure falls below the set
point pressure pc.

EB 2640 EN 7
Design and principle of operation
The two diaphragms (4.1) provide a certain
amount of safety when one of the diaphragms
ruptures and prevents the process medium
and external pressure medium from mixing.
The screw (12) prevents parts from falling
apart inadvertently while the regulator is be-
ing dismantled.
Fig.1: Functional drawings of the regulators
p1
p2
pc
15
3
11
2
4.1
12
6.1
6
8
1
9
5
3
2
12
7.1
7
11
4
15
p1
p2
Type2371-10 Type2371-11
1 Valve body
2 Seat
3 Plug
4Operating
diaphragm
4.1 Two diaphragms
5 Upper plug section
6 Adjustment screw
6.1 Adjustment opening
with blanking plug
7 Set point springs
7.1 Spring plate
8 Actuator housing
9Clamptting
11
Test connection or
leakage line
connection
12 Locking screw
15 Mechanical stop
p1Input pressure
p2Output pressure
pC
Set point pressure
(control pressure),
external

8 EB 2640 EN
Design and principle of operation
Stem locking for CIP or SIP
Seesection6.1onpage15.
TheType2371-10andType2371-11Regu-
latorscanbettedwithastemlockingtokeep
the plug in the open position. In this version,
the plug can be locked in the open position to
allow the valve to be cleaned (CIP = Cleaning
In Place or SIP = Sterilization In Place) while it
is open.
The stem can be locked in place pneumatical-
ly by an additional pneumatic unit with com-
pressedair connection(forTypes2371-10
and 2371-11) or manually using a special
pin(forType2371-11only).
The pneumatic and manual stem locking do
not affect the control function of the valve,
provided the stem locking is not engaged.
The pneumatic unit for the pneumatic stem
locking is located on the top of the regulator.
The unit can be mounted in any position since
theaxialxtureoftheunitallowsittoturn
360°.
The pin of the manual stem locking is screwed
into the adjustment opening in place of the
blanking plug.
Pneumatic stem locking·Types2371-10/-11 Manual stem locking·Type2371-11
Stem locking engaged
Fig.2: Stem locking
êpV∙G
1
/
8
connection
Pneumatic unit
Pin
Lock nut

EB 2640 EN 9
Design and principle of operation
Pneumatic stem locking
Type2371-10
To open the valve, apply a pressure pV(=
1bar)tothepneumaticunit.Thiscausesthe
plug stem to move together with the plug out
of the valve seat. A set point pressure pCmust
not be applied to the regulator in this case.
To switch the valve back to its control function,
remove the pressure pV(=1bar).
Type2371-11
To open the valve, apply a pressure pV(=
6bar)tothepneumaticunit.Thiscausesthe
plug stem to move together with the plug out
of the valve seat, opposing the spring force.
To switch the valve back to its control function,
remove the pressure pV(=6bar).
Manual stem locking
Type2371-11 only
To lock the stem into place, screw the pin into
the opening on top of the actuator housing in
place of the blanking plug. The end of the pin
comes to rest on the head of the set point
screw. As the pin is screwed into the valve, it
pushes the plug into the open position over
the set point screw and upper plug section. A
mechanical stop prevents it from being
screwed in any further, protecting the dia-
phragm from overstretching or rupturing. Se-
cure the position using the lock nut.
When the groove of the pin is completely con-
cealed, the stem locking is active, whereas a
visible groove means it is disengaged.

10 EB 2640 EN
Installation
4 Installation
Pay particular attention to correct hygiene
and ensure that regulators for the food and
pharmaceutical industries are kept absolutely
clean.
The tools used must be free of solvents and
grease. Only use a lubricant suitable for
foodstuffs (order no. 8150-9002) for parts
that must be lubricated.
Choose a place of installation that allows you
to freely access the regulator even after the
entire plant has been completed and allows
unobstructed set point adjustment.
Before installing the regulator in the pipeline,
clean the pipeline thoroughly to remove any
foreign particles in the plant which could
affect the regulator's proper functioning.
The plant must be designed and the pipelines
installed in such a way that the regulator can
be mounted and operated without any
tension. If necessary, support the pipeline
near to the connections. Do not attach
supports to the regulator itself.
Select a straight section of pipeline without
any disturbances as the site of installation for
the regulator (to ensure that the control func-
tionisnotaffectedbytheowconditions).
NOTICE
!
4.1 Mounting orientation
The regulator has an angle-style
valve body. The actuator
housing must face upwards. As
a result, the outlet must face to
the side in the installed position.
−Thedirectionofowmustmatchthe
direction indicated by the arrow on the
body (inlet at the bottom and outlet at the
side).
4.2 Shut-off valve and pressure
gauge
Install a manually operated shut-off valve
upstream and downstream of the regulator.
This allows the plant to be depressurized, if
required. In addition, it serves to relieve the
operating diaphragm of pressure when the
plant is not operated for extended periods.
A pressure gauge downstream of the regula-
tor allows the set point (to control the output
pressure p2) to be monitored.
1 Shut-off valve
2 Pressure gauge
3 Safety valve
p1Input pressure
p2Output pressure
Type2371-11
13
1
2
p1
p2
Fig.3: Installation drawing (Type2371-11)

EB 2640 EN 11
Operation
4.3 Safety valve
TheType2371-10andType2371-11Pres-
sure Reducing Valves are shut-off devices that
do not guarantee absolute tight shut-off.
When closed, these regulators can have a
leakagerate(seesection9onpage26).
As a result, the output pressure p
2
can rise to
the same level as the input pressure p1in a
plant which does not have its own consump-
tion.
The pressure in the entire system must not
exceed the maximum permissible pressure.
Corresponding safety equipment (e.g. safety
valve) must be installed downstream of the
regulator. Ensure that the pressure reducing
valve itself cannot exceed the specied
maximum pressure of 10bar/150psi.
The permissible temperature and pressure lim-
itsarespeciedontheregulator.
4.4 Leakage line connection
A leakage line can be connected to the
regulator when toxic or dangerous media are
used. In the event of a defective diaphragm
(e.g. diaphragm rupture), any process
medium that escapes can be fed through a
pipe to a safe location.
Adapt the pipe diameter to the connection at
the regulator.
WARNING
!
5 Operation
5.1 Start-up
First start up the regulator after mounting all
parts.
Fill the plant slowly with the process medium.
Avoid pressure surges. Open the shut-off
valves rst on the upstream pressure side.
Afterwards, open all the valves on the
consumer side (downstream of the regulator).
For optimal control, the required pressure set
point must be within the top end of the setting
range.
5.2 Adjusting the set point
The set point must be adjusted on starting up
the plant running under normal operating
conditions.
The pressure gauge located on the down-
stream (output) pressure side allows the ad-
justed set point to be monitored.
−ThesetpointadjustmentinType2371-
10 is pneumatic 1).
−ThesetpointofType2371-11isadjust-
ed manually by tensioning the set point
spring.
___
1) External supply air (e.g. compressed air,
pmax=8bar/115psi)required
Tip

12 EB 2640 EN
Operation
5.2.1 Set point·Type2371-
11
Manualsetpointadjustment∙SeeFig.1on
page7.
The set point is adjusted for the lowest output
pressure in the delivered state. The locking
screw (12) is not tightened.
The set point screw screwed in too far.
The regulator is blocked and the medium
ow through it is restricted. Pressure regula-
tion is no longer possible.
Only screw the set point screw up to the
point where the spring tension can still be
felt.
How to proceed:
1.
Remove the stopper. Use an Allen key
(3mm)toundothelockingscrew(12)ifit
is tightened (two turns counterclockwise).
2.
UseanAllenkey(8mm)toremovethe
blanking plug (6.1).
3.
Place the key through the opening to
reach the set point screw (6).
4.
Turn the set point screw (to tension the set
point spring) to adjust the set point:
−Turn clockwise : Increases the pressure
set point (the output pressure rises).
−Turn counterclockwise : Reduces the
pressure set point (the output pressure
drops).
Monitor the downstream pressure at a pres-
suregauge(seeFig.3onpage10).
NOTICE
!
The valve closes when the output pressure p
2
exceeds the pressure adjusted set point.
5.
Retighten the locking screw (12) to prevent
the set point screw (6) from being turned.
−Reinsert the stopper.

EB 2640 EN 13
Operation
1.
Position of the locking screw (12) with stopper
Fig.4: Set point adjustment of Type2371-11
3.
4.
Stopper∙Lockingscrew
(12) concealed
6.1
6
2.
5.

14 EB 2640 EN
Operation
5.2.2 Set point·Type2371-
10
Pneumaticsetpointadjustment∙SeeFig.1on
page7.
How to proceed:
1.
Connect the external set point pressure
lineattheG¼connection.Max.pressure
pC=8bar.
2.
Adjust the set point pressure pCto obtain
and keep the required pressure constant.
Monitor the downstream pressure at a pres-
suregauge(seeFig.3onpage10).
The valve closes when the output pressure p
2
exceeds the pressure adjusted set point.
5.3 Operation
AcorrectlysizedType2371-10/-11Pressure
Reducing Valve works automatically within its
control range.
We recommend after every start-up to check
that the regulator functions properly and to
adapt it to new operating conditions, if neces-
sary.
Fig.5: Pneumatic set point adjustment
5.4 Decommissioning
Close the shut-off valve upstream of the valve
and then close the shut-off valve downstream
of the valve.
Before performing any work on the regulator,
make sure the relevant plant section has been
depressurized and, depending on the process
medium, drained as well.
G¼connectionforthesetpointpressure
line at the side on the pressure unit
Note

EB 2640 EN 15
Cleaning and maintenance
6 Cleaning and maintenance
The pressure reducing valves do not require
any maintenance. Nevertheless, they are sub-
ject to natural wear, particularly at the seat,
plug and operating diaphragm.
Depending on the operating conditions, check
the regulator at regular intervals to avoid pos-
sible malfunctions.
Be aware of the risks on performing work on
pressurized or hot plant sections.
Hot process medium can escape uncontrol-
led on dismantling the regulator. Risk of scal-
ding.
Allow the regulator to cool down before de-
pressurizing and draining it and remove it
from the pipeline.
Check the seat and plug for wear. Check that
thePTFElayerofthediaphragm(seeFig.1,
Fig.12andFig.13)isnotdamaged(e.g.
cracks, milky coloring at the bends). This is
necessary for compliance with
EU1935/2004.
If leakage still occurs and there is no visible
signs of damage on the diaphragm, check the
connection between the plug support and
plug stem or the clamped connection between
thevalvebodyandbonnet(seesection6.2on
page19).
Tighten the connection to achieve a leak-proof
joint.
WARNING
!
6.1 Cleaning
To clean inside the regulator, the plug can be
kept in the open position in the version with
stem locking. This allows the entire plant with
the regulator installed to be cleaned (CIP =
Cleaning In Place or SIP = Sterilization In
Place) while the regulator is open (see ‘Stem
lockingforCIPorSIP’onpage8).
Stem locking:PneumaticforType2371-10/-
11·ManualforType2371-11
The disengaged stem locking does not affect
the regulator's control function.

16 EB 2640 EN
Cleaning and maintenance
Manual stem locking
Type2371-11
See ‘Stem locking for CIP or SIP’ on page
8.
How to proceed:
1.
Remove the blanking plug and screw the
pin (13) of the stem locking with the lock
nut (14) into the adjustment opening.
−The end of the pin comes to rest on the
head of the set point screw and keeps the
plug in the open position. A mechanical
stop prevents it from being screwed in
any further, protecting the diaphragm
from being overloaded.
2. Use the lock nut (14) to keep this position.
−When the groove of the pin is completely
concealed, the stem locking is active.
−A visible groove means it is disengaged.
−The control function of the valve is not
affected when the stem locking is
disengaged.
14
13
6
8
7
Manualstemlocking·Type2371-11
6 Set point screw
7 Set point springs
8ActuatorhousingofType2371-11
1 3 Pin
14 Lock nut
Fig.6: Manual stem locking

EB 2640 EN 17
Cleaning and maintenance
Pneumatic stem locking
Type2371-10 and Type2371-11
See section ‘Stem locking for CIP or SIP’ on
page 8.
Type2371-11
The pressure p
V
=6bar applied to the pneu-
matic unit opens the valve. This causes the
plug stem to move together with the plug out
of the valve seat and opens the valve.
How to proceed:
1. Connectthepressurelinewithmin.6mm
diametertotheG
1
/
8
connection.
2.
Apply a pressure pv = 6 bar to the
pneumatic unit. This causes the set point
screw (6) to move and the plug to move
out of the valve seat and opens the valve.
3.
To switch the valve back to its control
function, remove the pressure pV=6bar
to return the pressure back to atmospheric
pressure.
4.
The spring (16) pulls the actuating unit
(18) back. The plug stem can move again
for the control task.
Pneumaticstemlocking·Type2371-11
6 Set point screw
7 Set point springs
8ActuatorhousingofType2371-11
16 Spring
17 Actuatingunit/diaphragm
pVPressure for stem locking
Fig.7: Pneumatic stem locking
pV
17
16
8
6
7
Stem locking engaged
pV=6bar
Actuator housing
Stem locking
G
1
/
8
connection

18 EB 2640 EN
Cleaning and maintenance
Type2371-10
To open the valve, apply a pressure pV=
1bartothepneumaticunit.Thiscausesthe
plug stem to move together with the plug out
of the valve seat. A set point pressure pCmust
not be applied to the regulator in this case.
How to proceed:
1. Connectthepressurehosewithmin.6mm
diametertotheG
1
/
8
connection.
2.
Apply a pressure pv = 1 bar to the pneu-
matic stem locking. This causes the actuat-
ing unit (17) to move the plug stem togeth-
er with the plug out of the valve seat and
open the valve.
3.
To switch the valve back to its control func-
tion, remove the pressure pV(=1bar)to
return the pressure back to atmospheric
pressure.
4.
The spring (16) pulls the actuating unit
(18) back. The plug stem can move again
for the control task.
Pneumaticstemlocking·Type2371-10
8ActuatorhousingofType2371-10
15 Upper plug section with mechanical stop
16 Spring
17 Actuatingunit/diaphragm
pVPressure for stem locking
Fig.8: Pneumatic stem locking
pV
17
16
15
8
G
1
/
8
connection
Stem locking disengaged
pV=Atmosphericpressure
Actuator housing
Stem locking

EB 2640 EN 19
Cleaning and maintenance
6.2 Maintenance · Replacing
parts
SeeFig.1onpage7.
The regulator is subject to natural wear. De-
pending on the operating conditions and du-
ration of operation, regularly check the regu-
lator's ability to function.
In case the output pressure rises, for example
when all the consumers are closed and the
valve does not shut off tightly enough. This
may happen when the tight shut-off is im-
paired by either dirt or natural wear on the
seat and plug. However, it is important to take
into account that a maximum leakage of
0.05%oftheKVS or CVcoefcientinthecase
ofmetal-seatedplugsand0.01%inthecase
of soft-seated plugs is still permissible (see
section9onpage26).
6.3 Replacing the plug
Types2371-10/-11·Replacing the plug
The plug (3) is screwed into the plug support
(3.1). It can only be removed through the in-
let port. In this case, use the appropriate sock-
et wrench to unscrew the plug.
How to proceed:
1. Loosen the plug using the socket wrench
−DN15to25(NPS½to1):width across
ats 10
DN32to50(NPS1¼to2):width
across ats 13
2. Unscrew the plug (3) through the inlet port
p1. Remove the two washers and the seal.
3.
Prior to installing a new plug: Check the
seat and seat facing, so far as it is possi-
ble, for damage. In case of damage, the
regulator must be replaced or repaired.
Cutawaymodel·Unscrewingorscrewingintheplug
with a socket wrench
Screwed-in plug (3), plug support (3.1) seal
and washers
Fig.9: Replacing the plug of Type2371-11
We recommend also checking the diaphragm
for cracks and damage as a preventive mea-
sure.Refertosection6.4onpage21.
Assemble the new plug (3) in the reverse or-
der described for the disassembly. Insert the
two washers into the threaded hole with the
3
3.1
3
3.1
Input p1
Socket wrench

20 EB 2640 EN
Cleaning and maintenance
concave sides facing away from each other
(as shown in the drawing).
−Do not forget the PEEK seal!
Tightening torque
−DN15to25:5Nm
(NPS½to1)
−DN32to50:20Nm
(NPS1¼to2)
Insert washers as shown in the diagram.
Type2371-11∙Insertingthewashers
Fig.10: Soft-seated plug with plug support
PEEKseal
O-ring
V-port plug with EPDM soft seal
Retaining
washers