Samson Valve Series Service manual

Mounting and
Operating Instructions
EB 8135/8136 EN
Edition August 2011
Valve Series V2001
Three-way Valve for Heat Transfer Oil
Type 3535
Fig. 1 · Type 3535 Three-Way Valve with bellows seal and rod-type yoke (partial view)

2EB EB 8135/8136 EN
Safety instructions
General safety instructions
4
The valve is to be mounted, started up or serviced only by fully trained and
qualified personnel, observing the accepted industry codes and practices.
Make sure employees or third persons are not exposed to any danger.
All safety instructions and warnings in these mounting and operating
instructions, particularly those concerning assembly, start-up and
maintenance, must be observed.
4
The valves fulfill the requirements of the European Pressure Equipment
Directive 97/23/EC. Valves with a CE marking have a declaration of
conformity that includes information about the applied conformity assessment
procedure. The declaration of conformity is available on request.
4
For appropriate operation, make sure that the control valve is only used in
areas where the operating pressure and temperatures do not exceed the
operating values which are based on the valve sizing data submitted in the
order. The manufacturer does not assume any responsibility for damage
caused by external forces or any other external influence!
Any hazards which could be caused in the control valve by the process
medium, operating pressure, signal pressure or by moving parts are to be
prevented by means of the appropriate measures.
4
Proper shipping and appropriate storage are assumed.
NOTICE
4
For installation and maintenance work on the valve, make sure the relevant
section of the pipeline is depressurized and, depending on the process
medium, drained as well. If necessary, allow the control valve to cool down
or warm up to reach ambient temperature prior to starting any work on the
valve.
4
Prior to performing any work on the valve, make sure the supply air and
control signal are disconnected or blocked to prevent any hazards that could
be caused by moving parts.
4
Special care is needed when the actuator springs are pretensioned. These
actuators are labeled correspondingly and can also be identified by three
long bolts at the bottom of the actuator. Prior to starting any work on the
valve, you must relieve the compression from the pretensioned springs.

Contents
1 Design and principle of operation. . . . . . . . . . . . . . . . . . . . 4
1.1 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Mounting position. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Arrangement of control valve . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Strainer and bypass. . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 Maintenance–replacing parts . . . . . . . . . . . . . . . . . . . . . . 8
4.1 Replacing the bellows seal . . . . . . . . . . . . . . . . . . . . . . . 10
4.1.1 Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.1.2 Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2 Replacing the seat and plug . . . . . . . . . . . . . . . . . . . . . . 12
4.2.1 Mixing valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2.2 Diverting valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.3 Tools and tightening torques . . . . . . . . . . . . . . . . . . . . . . 20
5 Nameplate descriptions . . . . . . . . . . . . . . . . . . . . . . . . 21
5.1 DIN version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.2 ANSI version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6 Dimensions in mm and inches . . . . . . . . . . . . . . . . . . . . . 22
7 Customer inquiries . . . . . . . . . . . . . . . . . . . . . . . . . . 23
EB 8135/8136 EN 3
Contents

1 Design and principle of
operation
The Type 3535 Three-way Valve is con-
structed on the modular assembly principle
and can be combined with a pneumatic or
electric actuator as follows:
Valve Actuator
3535-P Pneumatic 3371-01xx
3535-IP Electropneumatic 3372-03xx
3535-E1 Electric 5824-30
3535-E3 3374
Design and principle of operation
4EB 8135/8136 EN
AB A AB A
BB
2.2
12.2
12
12.1
2.1
1
1.1
6
6.1
6.2
9
5.3
5
5.2
X
10.1
10.2
10.3
5.4
1.2
8.1
8.2
7
4
4.1
4.2
4.3
5.1
3.2
3.1
10.3
10.2
10.1
3.1
X
3.2
12
12.1
12.2
Fig. 2 · Sectional drawing (DN 32 bis 50), plug arrangement for mixing valve (left) and diverting valve (right)
5.3 Seal
5.4 Flange
6 Plug stem
6.1 Stem connector nut
6.2 Lock nut
7 Stem connector
8.1 Actuator stem
8.2 Rod-type yoke
9 Nut
10.1 Sleeve
10.2 Sleeve (short)
10.3 Sleeve
12 Nut
12.1 Washer
12.2 Lock washers
X Position for open-end
wrench
1 Valve body
1.1 Nuts
1.2 Body gasket
2.1 Top seat
2.2 Bottom seat
3.1 Top plug
3.2 Bottom plug
4 Threaded bushing
4.1 Bushing
4.2 Packing (spring-
loaded in DN 65
and higher)
4.3 Washer
5 Bellows seal with
plug stem
5.1 Coupling nut
5.2 Bellows housing

The plug arrangement determines whether
the three-way valve operates as mixing or
diverting valve.
In mixing valves, the media to be mixed en-
ter the valve at the ports A and B. The mixed
flow leaves through the port AB.
1.1 Technical data
The amount of flow from A or B to AB and
vice versa is determined by the cross-sec-
tional area between the seats and plugs.
The position of the plugs (3, 3.1, 3.2)
changes in response to changes of the con-
trol signal acting on the actuator.
The plug stem is sealed by a bellows and an
additional packing (4.2) and connected to
the actuator stem (8.1) by the stem connec-
tor (7).
EB 8135/8136 EN 5
Design and principle of operation
Nominal size DN 15 to 80 NPS ½ to 3
Material Sph. gra-
phite iron
EN-JS1049
Cast steel
1.0619
Stainless
steel
1.4408
Spheriodal
graphite
iron A 395
Cast steel
A 216
WCC
Stainl. steel
A 351
CF8M
Nominal pressure PN 16 · PN 25 Class 150 · Class 300
End
connections Flanges EN 1092-1 Form B1,
Ra 3.2 to 12.5 µm
EN 1092-1, groove Form D Raised face
Seat and plug sealing Metal sealing
Characteristic Linear
Rangeability 30:1 up to DN 25/NPS 1 · 50:1 for DN 32/NPS 1½ or larger
Temperature range –10 to 350 °C 14 to 660 °F
Leakage rate DIN EN 1349:
0.05 % of KVS coefficient ANSI/FCI 70-2:
0.05 % of CVcoefficient
Materials
Nominal size DN 15 to 80 NPS ½ to 3
Valve body Spheriodal
graphite iron
EN-JS1049
Cast steel
1.0619
Stainless
steel
1.4408
Spheriodal
graphite iron
A 395
Cast steel
A 216
WCC
Stainl. steel
A 351
CF8M
Valve bonnet Cast steel S235JR (St 37) 1.4408 Cast steel S235JR (St 37) 1.4408
Seat and plug Seat £DN 25: 1.4305 · ³DN 32: 1.4104 £NPS 1: 1.4305 · ³NPS 1½: 1.4104
Plug 1.4305
Bellows seal 1.4541 · 1.4301
Packing PTFE
Body gasket Graphite on metal core

2 Installation
Valve and actuator are supplied already as-
sembled by the manufacturer.
For more details on the actuator used,
please refer to the appropriate mounting
and operating instructions.
2.1 Mounting position
The valve can be mounted in any position.
However, the limitations due to the actuator
used must be strictly observed.
CAUTION!
The valve must be installed free of stress and
free of excessive vibrations. If necessary,
support the pipelines near the connections.
Do not install supports on the valve or on the
actuator. Thoroughly flush the pipeline prior
to installation of the valve.
Pipeline routing
To allow the control valve to work properly,
the pipeline upstream and downstream of
the valve must be straight and free of ob-
structions for a length of at least 6 times the
pipe diameter (DN). Contact SAMSON if
this length cannot be met during installation.
Clean out the pipeline thoroughly prior to in-
stalling the valve.
2.2 Arrangement of control valve
Depending on the task to be performed, the
control valve is arranged as illustrated in
Fig. 3.
How the plugs are arranged for mixing or
diverting valves is specified on the label at-
tached to the valve body.
Fail-safe action: Valve shuts off the heating
medium supply or opens the supply of cool-
ing medium.
2.3 Strainer and bypass
We recommend installing a SAMSON
Type 2 N Strainer upstream of the valve,
and upstream of both ports for mixing
valves.
In addition to a bypass line, shut-off valves
should be installed both upstream of the
strainer and downstream of the control valve
so that the plant need not be shut down for
maintenance routines.
Installation
6EB 8135/8136 EN
KVS and CVcoefficients, seat diameters and travel
Nominal size DN 15 20 25 32 40 50 65 80
NPS ½¾1 –1½ 2 2½3
Kvs coefficients 46.381620325080
Cvcoefficients 5 7.5 9.4 – 23 37 60 94
Seat diameter mm/in 24 mm · 0.94” 40 mm · 1.57” 65 mm · 2.56”
Travel mm/in 15 mm · 0.59” 15 mm · 0.59” 15 mm · 0.59”

EB 8135/8136 EN 7
Installation
Mixing service Diverting service
Temperature control Q = constant Flow rate control Q = 0 to 100 %
Fail-safe action: FA = Actuator stem extends, FE = Actuator stem retracts
Heating using a mixing valve (FA) or cooling using a mixing valve (FE)
Installation in flow pipe Installation in return flow pipe
Heating using a diverting valve (FA) or cooling using a diverting valve (FE)
Installation in return flow pipe Installation in flow pipe
AAB
B
Flow
Return flow
A
AB
B
Flow
Return flow
AAB
B
Flow
Return flow
AAB
B
Flow
Return flow
AAB
B
Flow
Return flow
A
AB
B
Flow
Return flow
AAB
B
Flow
Return flow
AB A
B
Flow
Return flow
Fig. 3 · Typical applications

3 Operation
Operating instructions depend on the actua-
tor used. Refer to the mounting and operat-
ing instructions for the appropriate actuator.
4 Maintenance–replacing parts
The valve is subject to wear and tear, espe-
cially at the seat, plug, bellows seal and
packing.
Depending on the application conditions
that prevail, the valve must be inspected at
appropriately scheduled intervals to prevent
any problems before they occur.
If any leaks occur to the atmosphere, the
packing may leak. If the valve does not shut
off properly, this may be because tight
shut-off is prevented by dirt or other impuri-
ties between the seat and plug or because
their facings have been damaged.
Valves in DN 15 to 25 have a one-piece
plug with the same arrangement for both
mixing and diverting valves.
Valves in DN 32 and larger have two V-port
plugs. In mixing valves, the plugs move in-
wards into the seats, whereas the plugs of
the diverting valves move outwards into the
seats.
To keep the exact position of the plug,
spacer sleeves are used to keep the plug on
the plug stem. The different arrangement for
valves in DN 32 to 50 and for valves in
DN 65 and 80 as mixing and diverting
valves is specified in the section on assem-
bly.
We recommend removing the parts, thor-
oughly cleaning them, and replacing them
with new parts, if necessary.
Operation
8EB 8135/8136 EN

CAUTION!
If you intend carrying out mainten-
ance work on the valve, first depres-
surize the relevant plant section and,
depending on the process medium,
drain it as well. Let the plant section
cool down to reach ambient tempe-
rature, if high temperatures prevail.
Prior to starting any work, discon-
nect the electric or pneumatic control
signal for the actuator. On pneuma-
tic actuators, additionally remove the
signal pressure line.
As the process medium cannot drain
completely out of the valve, be awa-
re that some of the process medium
could still be trapped in the valve.
We recommend that you remove the
valve from the pipeline.
Note:
The tightening torques and special tools re-
quired for installing and removing the seat
are listed in the table on page 20.
NOTICE
Prior to carrying out any repairs, always
separate the actuator from the valve by re-
moving screws on the stem connector (7)
and undoing the nut (9). Then lift the actua-
tor off the valve (see Fig. 2).
EB 8135/8136 EN 9
Maintenance–replacing parts

4.1 Replacing the bellows seal
If the packing leaks, this is due to a dam-
aged bellows seal.
The entire bellows assembly together with
the packing (4.2) must be replaced.
We recommend renewing the top seal (5.3)
and the bottom body gasket (1.2) of the bel-
lows housing as well.
Mixing and diverting valves in nominal sizes
DN 32 to 80 differ from one another in the
arrangement of their plugs and sleeves (see
Fig. 4), where as mixing and diverting
valves in nominal sizes DN 15 to 25 have
the same plug and sleeve arrangement.
4.1.1 Disassembly
1. Unscrew the stem connector nut (6.1)
and lock nut (6.2) from the plug stem of
valves in DN 50 or smaller.
2. Unscrew the coupling nut (5.1) from the
bellows housing. Remove the nuts (1.1)
and lift off the flange (5.4).
3. Pull the bellows housing (5.2) with the
bellows assembly out of the body as far
as they will go. Place an open-end
wrench (SW 10 for £DN 50 or SW 13
for ³DN 65) at the side on the hexagon
(X) or at the flattened area of the plug
stem to hold it stationary. Undo nut (12)
and remove wrench.
4. Unthread nut (12). Remove the two lock
washers (12.2) and washer (12.1).
5. DN 15 to 25:
Carefully pull the plug stem (6) together
with the bellows assembly (5) and bel-
lows housing (5.2) from the top out of
the valve body.
DN 32 to 80:
Keep the bottom plug of diverting valves
or the bottom sleeve of mixing valves on
the plug stem. Use a long screw (M8 for
nominal sizes DN 32 to 50 and M12 for
DN 65 and 80) to keep the plugs (3.x)
and sleeves (10.x) in the right order.
Carefully lift the plug stem together with
the bellows assembly (5) and bellows
Maintenance–replacing parts
10 EB 8135/8136 EN
AB A
B
12.2
12
12.1
1.1
6.1
6.2
5.3
5
5.2
X
5.4
1.2
4.2
4.3
5.1
3.2
Fig. 4 · Mixing valve DN 32 to 50

housing (5.2) upwards out of the body.
Guide the screw (to hold the plugs and
sleeves) into the body and push up-
wards, allowing the plugs and sleeves to
slide onto the screw.
6. Clean all parts thoroughly and check
them for damage.
Replace the plug stem together with the
bellows seal and packing.
4.1.2 Reassembly
1. Apply lubricant (order no. 8150-0119)
to the seal (5.3) and the threaded part
of the bellows housing. Place seal (5.3)
on the bellows housing (5.2).
Insert the bellows assembly (5) together
with plug stem into the bellows housing.
Finger-tighten the coupling nut (5.1) at
first.
Insert body gasket (1.2) into the body.
2. DN 15 to 25:
Place ready-assembled bellows assem-
bly on the valve body, while guiding the
plug stem through the holes in the plug.
DN 32 to 80:
Gradually insert the plug stem of the
ready-assembly bellows assembly (5)
into the valve body, allowing the plugs
and sleeves to slide from the screw (used
to hold the plugs and sleeves) onto the
plug stem.
3. First place the washer (12.1) and then
the pair of serrated lock washers (12.2)
onto the plug stem, making sure the
coarsely serrated surfaces of the lock
washers face each other and the radial
ribs face outwards.
Screw the nut (12) onto the plug stem by
hand.
Note: For nominal sizes DN 15 to 50, a
special tool designed to hold the washers
(12.1 and 12.2) can be ordered from
SAMSON (see table).
Especially on valves in nominal sizes DN 15
to 25, it is difficult to install the washers on
the plug stem due to insufficient clearance.
Maintenance–replacing parts
EB 8135/8136 EN 11
2.2
2.1
12.1
12.2
12 3
Fig. 5 · Mixing valve DN 15 to 25
2.2
3.2
3.1
2.1
10.2
10.3
10.1
Fig. 6 · Mixing valve DN 32 to 50

4. Slightly pull out the bellows housing
(5.2) together with the bellows assem-
bly. Place an open-end wrench at the
side on the hexagon or the flattened part
(X) of the plug stem to hold the stem sta-
tionary and to prevent the bellows from
turning.
CAUTION!
Do not turn the bellows seal.
Firmly tighten the nut (12) to secure the
plugs and the sleeves:
Valve DN 15 to 50 DN 65 to 80
Nut (12) 15 Nm 25 Nm
Remove the open-end wrench.
5. Align flange (5.4) to the bellows housing
(5.2), making sure the body gasket (1.2)
is correctly positioned. Tighten nuts
(1.1):
Valve DN 15 to
25 DN 32 to 50 DN 65 to 80
Nuts (1.1) M10
10 Nm M12 30 Nm M16 90 Nm
Firmly tighten the coupling nut (5.1) with
80 Nm.
6. DN 15 to 50:
Thread the lock nut (6.2) and stem con-
nector nut (6.1) onto the top end of the
plug stem.
Adjust the stem connector nut (6.1) to
keep the dimension of 50 mm between
the top of the bellows assembly (5) and
the top of the stem connector nut (6.1)
when the plug stem is completely in-
serted in the valve. Refer to the dimen-
sional diagram on page 23.
Mount the actuator following the instructions
in the corresponding mounting and operat-
ing instructions.
4.2 Replacing the seat and plug
When replacing the seat and/or plug, we
recommend replacing the seal (5.3) at the
top and the body gasket (1.2) at the bottom
of the bellows housing as well.
Maintenance–replacing parts
12 EB 8135/8136 EN
AB A
B
12.2
12
12.1
1.1
6.1
6.2
5.3
5
5.2
X
5.4
1.2
4.2
4.3
5.1
3.2
Fig. 7 · Mixing valve DN 32 to 50

4.2.1 Mixing valve
Disassembly
1. Unthread stem connector nut (6.1) and
lock nut (6.2) from the plug stem of
valves in DN 50 and smaller.
2. Unthread coupling nut (5.1) from the
bellows housing. Remove nuts (1.1) and
lift off flange (5.4).
3. Pull out bellows housing (5.2) and bel-
lows assembly as far as they will go.
Place an open-end wrench (SW 10 for
valves £DN 50 or SW 13 for valves
³DN 65) at the side on the hexagon (X)
or at the flattened area of the plug stem
to hold the stem stationary. Undo nut
(12) and remove wrench.
4. Unthread nut (12). Remove the two lock
washers (12.2) and washer (12.1).
For valves in DN 32 to 80, pull bottom
sleeve (10.3 or 11.4) off the plug stem.
5. Lift bellows housing (5.2) together with
the bellows assembly (5) and carefully
pull the plug stem (6) out of the valve
body.
Pull the bellows assembly (5) out of the
bellows housing and remove the body
gasket (1.2).
Carefully clean all parts and check them
for damage.
Replace defective parts with new ones.
6. For valves in DN 32 and larger, remove
sleeve (10.1 or 11.1).
Unscrew the top seat (2.1)usingasuit
-
able seat wrench (see table on page 20).
7. DN 15 to 25
Lift plug (3) out of the body.
DN 32 to 50
Lift top plug (3.1), sleeve (10.2) and bot-
tom plug (3.2) out of the body.
DN 65 and 80
Lift top plug (3.1), sleeves (11.2 and
11.3) and bottom plug (3.2) out of the
body.
8. Unscrew the bottom seat (2.2) from of
the body.
Clean all parts. Check them and, if nec-
essary, machine them or replace them
with new parts.
EB 8135/8136 EN 13
Maintenance–replacing parts
2.2
2.1
12.1
12.2
12 3
Fig. 8 · Mixing valve DN 15 to 25
12.1
12.2
12
11.1
11.2
11.3
11.4
3.1
3.2
Fig. 9 · Mixing valve DN 65 and 80

Reassembly
1. Apply lubricant (order no. 8150-0119)
to the seal (5.3) and the threaded part
of the bellows housing.
Place seal (5.3) on the bellows housing
(5.2).
Insert the bellows assembly (5) with plug
stem into the bellows housing.
Finger-tighten the coupling nut (5.1) at
first.
2. Apply lubricant (order no. 8150-0119)
to the thread and sealing cone of the
new or machined seats.
3. Use the seat wrench to screw in the bot-
tom seat (2.2), observing the correct
tightening torques:
Valve DN 15 to
25 DN 32 to 50 DN 65 and 80
Seat thread M32x1.5 M58x1.5 M90x1.5
Tightening
torque 120 Nm 500 Nm 1050 Nm
4. DN 15 to 25
Insert plug (3) into bottom seat (2.2).
DN 32 to 50
Insert bottom plug (3.2) into bottom seat
(2.2).
Place the short sleeve (10.2) and top
plug (3.1) one after the other onto the
bottom plug. To keep them in order, in-
sert a long M8 screw through the bottom
plug.
DN 65 and 80
Insert bottom plug (3.2) into bottom seat
(2.2).
Place two short sleeves (11.3 and 11.2)
and the top plug one after the other onto
the bottom plug. To keep them in order,
insert a long M8 screw through the bot-
tom plug.
5. Screw top seat (2.1) into the body, en-
suring that the top plug can easily slide
into the seat. Use tightening torque listed
in the table for step 3.
Insert body gasket (1.2) into top valve
flange.
Maintenance–replacing parts
14 EB 8135/8136 EN
AB A
B
12.2
12
12.1
1.1
6.1
6.2
5.3
5
5.2
X
5.4
1.2
4.2
4.3
5.1
3.2
Fig. 10 · Mixing valve DN 32 to 50

6. DN 15 to 25
Carefully place the bonnet onto the
valve, while guiding the plug stem into
the plug (3).
DN 32 to 50
Slide sleeve (10.1) over the plug stem.
Carefully place on the bonnet, while
guiding the plug stem through the top
plug (3.1), sleeve (10.2) and bottom
plug (3.2) and at the same time remove
the M8 screw.
Slide sleeve (10.3) from underneath
onto the plug stem.
DN 65 and 80
Slide sleeve (11.1) over the plug stem.
Carefully place on the bonnet, while
guiding the plug stem through the top
plug (3.1), two sleeves (11.2 and 11.3)
and bottom plug (3.2) into the body and
at the same time remove the M12 screw.
Slide sleeve (11.4) from underneath
onto the plug stem.
7. First place the washer (12.1) and then
the pair of serrated lock washers (12.2)
onto the plug stem, making sure the
coarsely serrated surfaces of the lock
washers face each other and the radial
ribs face outwards.
Finger-tighten the nut (12) onto the plug
stem.
Note: For nominal sizes DN 15 to 50, a
special tool designed to hold the washers
(12.1 and 12.2) can be ordered from
SAMSON (see table).
Especially on valves in nominal sizes DN 15
to 25, it is difficult to install the washers on
the plug stem due to insufficient clearance.
8. Slightly pull out the bellows housing
(5.2) together with the bellows assem-
bly. Place an open-end wrench at the
side on the hexagon or the flattened part
(X) of the plug stem to hold the stem sta-
tionary and to prevent the bellows from
turning.
CAUTION!
Do not turn the bellows seal.
EB 8135/8136 EN 15
Maintenance–replacing parts
2.2
2.1
12.1
12.2
12 3
Fig. 11 · Mixing valve DN 15 to 25
12.1
12.2
12
11.1
11.2
11.3
11.4
3.1
3.2
Fig. 12 · Mixing valve DN 65 and 80

Tighten nut (12) to fasten the plug and
sleeves:
Valve DN 15 to 50 DN 65 to 80
Nut (12) 15 Nm 25 Nm
Remove the open-end wrench.
9. Align flange (5.4) to the bellows housing
(5.2), making sure the body gasket (1.2)
is correctly positioned.
Tighten nuts (1.1):
Valve DN 15 to
25 DN 32 to 50 DN 65 to 80
Nuts (1.1) M10
10 Nm M12 30 Nm M16 90 Nm
Firmly tighten the coupling nut (5.1) with
80 Nm.
10. DN 15 to 50:
Thread the lock nut (6.2) and stem con-
nector nut (6.1) onto the top end of the
plug stem.
Adjust the stem connector nut (6.1) to
keep the dimension of 50 mm between
the top of the bellows assembly (5) and
the top of the stem connector nut (6.1)
when the plug stem is completely in-
serted into the valve. Refer to the dimen-
sional diagram on page 23.
Mount the actuator following the instructions
in the corresponding mounting and operat-
ing instructions.
4.2.2 Diverting valve
Disassembly
1. Unscrew the stem connector nut (6.1)
and lock nut (6.2) from the plug stem of
valves in DN 50 or smaller.
2. Unscrew the coupling nut (5.1) from the
bellows housing. Remove the nuts (1.1)
and lift off the flange (5.4).
3. Pull the bellows housing (5.2) with the
bellows assembly out of the body as far
as they will go. Place an open-end
wrench (SW 10 for £DN 50 or SW 13
for ³DN 65) at the side on the hexagon
(X) or at the flattened area of the plug
stem to hold it stationary. Undo nut (12)
and remove wrench.
4. Unthread nut (12). Remove two lock
washers (12.2) and washer (12.1).
Maintenance–replacing parts
16 EB 8135/8136 EN
1.1
6.1
6.2
5.3
5
5.2
X
5.4
1.2
4.2
4.3
5.1
Fig. 13 · Valve bonnet with bellows seal

5. Pull the bellows assembly (5) from the
bellows housing and remove body gas-
ket (1.2).
Clean all parts thoroughly and check
them for damage.
Replace defective parts.
6. DN 15 to 25
Unscrew top seat (2.1). Take plug (3)
out of the body and remove bottom seat
(2.2).
DN 32 to 50
Remove top seat (3.1) together with the
three sleeves (10.1, 10.2, 10.3) from
the body.
DN 65 and 80
Remove top seat (3.1) together with the
four sleeves (11.1, 11.2, 11.3, 11.4)
from the body.
7. DN 32 to 80
Use a suitable seat wrench (see
page 20) to unscrew the top and bottom
seat (2.1, 2.2) out of the body.
Remove bottom plug (3.2) from the
body.
Carefully clean all parts and check them
for damage. If necessary, machine or
replace any defective parts.
Reassembly
1. Apply lubricant (order no. 8150-0119)
to the seal (5.3) and the threaded part
of the bellows housing.
Place seal (5.3) on the bellows housing
(5.2).
Insert the bellows assembly (5) with plug
stem into the bellows housing.
Finger-tighten the coupling nut (5.1) at
first.
2. Apply lubricant (order no. 8150-0119)
to the thread and sealing cone of the
new or machined seats.
3. DN 15 to 25
Screw in bottom seat (2.2) and tighten:
Valve DN 15 to 25
Seat thread M32 x 1.5
Tightening torque 120 Nm
Place plug (3) in bottom seat. Screw in
top seat (2.1) allowing the plug to slide
into the seat from underneath. Tighten
top seat with the same tightening torque.
DN 32 to 50
Insert bottom seat (3.2) into the body.
Use the seat wrench to screw in the bot-
tom seat (2.2) and top seat (2.1) one af-
ter the other:
Valve DN 32 to 50
Seat thread M58 x 1.5
Tightening torque 500 Nm
EB 8135/8136 EN 17
Maintenance–replacing parts
2.2
2.1
10.1
10.2
10.3
3.2
3.1
Fig. 14 · Diverting valve DN 32 to 50

Place top plug (3.1) and three sleeves
(10.1, 10.2, 10.3) onto the plug stem
one after the other.
DN 65 and 80
Insert bottom plug (3.2) into the body.
Use the seat wrench to screw in the bot-
tom seat (2.2) and top seat (2.1) one af-
ter the other:
Valve DN 65 and 80
Seat thread M90 x 1.5
Tightening torque 1050 Nm
Place top plug (3.1) and four sleeves
(11.1, 11.2, 11.3, 11.4) onto the plug
stem one after the other.
4. For valves in DN 32 and larger, insert
bottom plug into bottom seat.
Insert body gasket (1.2) into body
flange.
Carefully place the bellows housing
(5.2) onto the body, while guiding the
plug stem (6).
Hold the plug in the seat to push the
plug stem in the middle through the plug
bore.
5. First place the washer (12.1) and then
the pair of serrated lock washers (12.2)
onto the plug stem, making sure the
coarsely serrated surfaces of the lock
washers face each other and the radial
ribs face outwards.
Finger-tighten the nut (12) onto the plug
stem.
Note: For nominal sizes DN 15 to 50, a
special tool designed to hold the washers
(12.1 and 12.2) can be ordered from
SAMSON (see table).
Especially on valves in nominal sizes DN 15
to 25, it is difficult to install the washers on
the plug stem due to insufficient clearance.
6. Slightly pull out the bellows housing
(5.2) together with the bellows assem-
bly. Place an open-end wrench at the
side on the hexagon or the flattened part
Maintenance–replacing parts
18 EB 8135/8136 EN
12.1
12.2
12
11.1
11.2
11.3
11.4
2.1
3.1
3.2
2.2
Fig. 15 · Diverting valve DN 65 and 80
12.1
12.2
12
11.1
11.2
11.3
11.4
3.1
3.2
Fig. 16 · Diverting valve DN 32 and 50

(X) of the plug stem to hold the stem
stationary and to prevent the bellows
from turning.
CAUTION!
Do not turn the bellows seal.
Tighten nut (12) to fasten the plug and
sleeves:
Valve DN 15 to 50 DN 65 to 80
Nut (12) 15 Nm 25 Nm
Remove the open-end wrench.
7. Align flange (5.4) to the bellows housing
(5.2), making sure the body gasket (1.2)
is correctly positioned.
Tighten nuts (1.1):
Valve DN 15to
25 DN 32 to 50 DN 65 to 80
Nuts (1.1) M10
10 Nm M12 30 Nm M16 90 Nm
Firmly tighten the coupling nut (5.1) with
80 Nm.
8. DN 15 to 50:
Thread the lock nut (6.2) and stem con-
nector nut (6.1) onto the top end of the
plug stem.
Adjust the stem connector nut (6.1) to
keep the dimension of 50 mm between
the top of the bellows assembly (5) and
the top of the stem connector nut (6.1)
when the plug stem is inserted com-
pletely into the valve. Refer to the dimen-
sional diagram on page 23.
Mount the actuator following the instructions
in the corresponding mounting and operat-
ing instructions.
EB 8135/8136 EN 19
Maintenance–replacing parts

4.3 Tools and tightening torques
Maintenance–replacing parts
20 EB 8135/8136 EN
Valve nominal size DN 15 to 25
NPS ½ to 1 DN 32 to 50 NPS 1½ to 2 DN 65 to 80 NPS 2½ to 3
Seat wrench 1280-3010 1280-3011 1280-0305
Tool to retain 1280-3059 for washer (12.1) and lock washer (12.2)
Tightening torque (±10 %)
Valve seat 120 Nm (M32x1.5) 500 Nm (M58x1.5) 1050 Nm (M90x1.5)
Nut (12) 15 Nm 25 Nm
Body nut (1.1) 10 Nm (M10) 30 Nm (M12) 90 Nm (M16)
Coupling nut (5.1) 80 Nm