Samson 45-6 Service manual

Differential Pressure Regulator
Type 45-6
Mounting and
Operating Instructions
EB 3226 EN
Edition March 2008
Type 45-6 (0.1 to 1 bar, DN 15)

Contents Page
1 Design and principle of operation . . . . . . . . . . . . . . . . . . . 4
2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 Mounting position . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Strainer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Shut-off valves, gauges . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2 Set point adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4 Maintenance – Replacing parts . . . . . . . . . . . . . . . . . . . . . 7
4.1 Cleaning and replacing the plug . . . . . . . . . . . . . . . . . . . . 7
4.2 Replacing the diaphragm . . . . . . . . . . . . . . . . . . . . . . . . 8
5 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6 Nameplate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
7 Customer inquiries . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8 Dimensions and weights . . . . . . . . . . . . . . . . . . . . . . . 11
2EB 3226 EN
Contents
Note!
These Mounting and Operating Instructions EB 3226 EN refer to the Type 45-6 Differential
Pressure Regulator manufactured from July 2005 onward (0075, see nameplate).

EB 3226 EN 3
Safety instructions
General safety instructions
4
The differential pressure regulator must be installed, started up and serviced
by skilled or semi-skilled staff in accordance with good engineering practice
so that employees and third persons are not exposed to danger.
All safety instructions and warnings given in these mounting and operating
instructions, particularly those concerning installation, start-up, and
maintenance, must be strictly observed.
4
The regulator complies with the requirements of the European Pressure
Equipment Directive 97/23/EC. The declaration of conformity issued for a
regulator bearing the CE marking includes information on the applied
conformity assessment procedure and is provided on request.
4
To ensure appropriate use, only use the regulator in applications where the
operating pressure and temperatures do not exceed the operating values
specified in the order.
Note that the manufacturer does not assume any responsibility for damage
caused by external forces or any other external factors. Take appropriate
safety precautions to prevent hazards that may be caused by the process
medium, the operating pressure, or moving parts in the regulator.
4
Make sure the regulator is shipped and stored properly.
Important!
4
Depending on the field of application, allow the regulator to cool down or
warm up to reach ambient temperature prior to starting any work on the
regulator. Always depressurize the relevant section of the plant and, if
necessary, also drain the pipeline prior to removing the regulator from the
pipeline.
4
When carrying out a pressure test on the section of the plant equipped with
a pressure regulator, prevent the actuator from being damaged by the test
pressure.
4
Protect the regulator against frost if it is used to control freezing media.
Note! Non-electrical control valves, whose valve bodies are not lined with
an insulating material coating, do not have their own potential ignition
source according to the ignition risk assessment stipulated in EN 13463-1:
2001, section 5.2, even in the rare incident of an operating fault. Therefore,
such valve versions do not fall within the scope of Directive 94/9/EC.

1 Design and principle of
operation
The differential pressure regulator consists of
a valve with a balanced plug and of an
opening actuator with an operating dia-
phragm and a spring assembly.
The differential pressure regulator is de-
signed to maintain the differential pressure
at the adjusted set point. The valve opens as
the differential pressure rises.
The differential pressure to be controlled is
transmitted to the operating diaphragm
(6.1), where it is converted into a force. For
this purpose, the downstream pressure (low
pressure) is directed through the hole in the
valve body (11.1) to the top (low-pressure)
diaphragm chamber of the actuator. The
4EB 3226 EN
Design and principle of operation
Fig. 1 · Sectional drawing
1 Valve body
1.1 Connection nut
1.2 Stopper (version for DN 32 to 50)
2 Seat
3 Valve plug (pressure balanced)
3.1 Plug nut
3.2 Guide nipple of plug
3.3 Screw ferrule (DN 32 to 50)
3.4 Plug stem
4 Nut of diaphragm plate
5 Diaphragm plate
6 Actuator
6.1 Operating diaphragm
7 Screws
8 Positioning spring(s)
9 Spring plate
10 Set point adjuster
11 Control line1)
11.1 Hole in the valve body
12 Manual adjuster
Tightening torques
Item DN Nm
1.2 Stopper 15 to 25
32 to 50 70 110
3.1 Valve plug 15 to 25
32 to 50 4 8
3.3 Screw ferrule 32 to 50 110
7 Screw 15 to 32
40 to 50 8 18
p1p2
1.2
1
1.1
2
3.4
4
11.1
3.1
3
3.2
3.3
5
11
6
6.1
7
8
9
10
Type 45-6 with screwed ends
(DN 40/50)
12
Manual adjuster
(0.1 to 1 bar, DN 15 to 32)
1) Control line turned into plane of projection.
It is routed in front of the valve and connected to the high-pressure chamber (p1).

upstream pressure (high pressure) is routed
through the attached control line (11) to act
on the diaphragm in the high-pressure
chamber.
The differential pressure creates a force at
the operating diaphragm (6.1) which is
used to position the plug depending on the
force of the positioning springs (8). The
force of the spring assembly is modified by
turning the set point adjuster (10).
The principle of operation described above
also applies to regulators with a manual ad-
juster (0.1 to 1 bar, DN 15 to 32). The posi-
tioning springs, however, are located in an
enclosed housing. The set point is adjusted
at the manual adjuster (12) using the scale.
Note!
For external connection of the control lines
(special version) observe the following steps:
Connect the high-pressure line of the plant to
the high-pressure connection (+) of the actua-
tor (bottom diaphragm chamber)
Connect the low-pressure line of the plant to
the low-pressure connection (–) of the actua-
tor (top diaphragm chamber) as illustrated
in Fig. 1 (left).
2 Installation
2.1 Mounting position
The differential pressure regulators must be
installed in horizontal bypass or short-circuit
pipes with the actuator suspended down-
ward (see Fig. 2).
Regulators in sizes DN 15 to DN 25 can
also be installed in vertical pipelines. For
medium temperatures above 80 °C, the reg-
ulator must not be installed with the dia-
phragm actuator pointing upward. The me-
dium must flow through the valve in the di-
rection indicated by the arrow on the body.
2.2 Strainer
Since sealing parts, globules, and other im-
purities carried along by the medium may
impair the proper functioning of the valve
and especially the tight shut-off, a strainer
(e.g. SAMSON Type 1NI) must be installed
upstream of the differential pressure regula-
tor.
The strainer must be installed so that the me-
dium flows through it in the direction indi-
cated by the arrow on the strainer body.
The filter element must be suspended down-
ward. Ensure that there is sufficient space
available to remove the filter.
EB 3226 EN 5
Installation
Fig. 2 · Installation examples
_+
+
_
+
_
_
+
1
2
1
2
344
44
3
3
3
1 Strainer
2 Regulator 3 Shut-off valve 4 Pressure gauge
Installation in a short-circuit pipe
Installation in a bypass pipe

2.3 Shut-off valves, gauges
We recommend the installation of hand-op-
erated shut-off valves both upstream of the
strainer and downstream of the regulator.
This allows the plant to be shut down for
cleaning and maintenance routines or when
it is not operated for extended periods. In-
stall pressure gauges upstream and down-
stream of the valve to monitor the pressures
prevailing in the plant.
3 Operation
3.1 Start-up
Fill the plant very slowly on start-up. When
pressure-testing the pipelines with the regu-
lator installed, make sure the test pressure
does not exceed 1.5 times the nominal pres-
sure.
3.2 Set point adjustment
The required differential pressure is adjusted
at the set point adjuster (10) or the manual
adjuster (12) by loading the spring(s).
4Turn the adjuster clockwise to increase
the differential pressure.
4Turn the adjuster counterclockwise to
reduce the differential pressure.
In the case of regulators with set point
ranges from 0.1 to 1 bar in sizes DN 15 to
32, the positioning springs are located in
the actuator housing,
The set point can be adjusted directly at the
manual adjuster (12) on the basis of the
scale value (see Fig. 5).
One turn of the manual adjuster will change
the differential pressure by 0.033 bar.
Note!
Do not adjust the set point to a scale value
smaller than “1”!
Under certain conditions, the set point can-
not be adjusted anymore as a result.
In this case, the following steps are recom-
mended:
– Relieve the process pressure from both
sides of the regulator.
– Turn the manual adjuster counterclockwise
as far as it will go to its lowest position.
– Turn the manual adjuster back clockwise
at least past the scale value “1” to “2”.
– The regulator can now be readjusted.
6EB 3226 EN
Operation
0.2
0.4
0.6
0.8
1.0
1.2
0123456
Δp
Fig. 3 · Set point adjustment according to scale
Division of scale
Fig. 4 · Manual adjuster (0.1 to 1 bar / DN 15 to 32)
12
Set point adjustment
using the
manual adjuster

4 Maintenance – Replacing
parts
The regulator is maintenance-free, but is
subject to wear and tear, especially at the
seat, plug and operating diaphragm.
Depending on the application conditions
that prevail, the regulator must be inspected
at appropriately scheduled intervals to pre-
vent any problems before they occur.
Details on faults and the recommended
action can be found in the table on page 8.
If a problem cannot be solved with the help
of the information specified in the table,
contact SAMSON. In order to replace the
plug and operating diaphragm, proceed as
described in sections 4.1 and 4.2.
Caution!
To carry out any work on the differ-
ential pressure regulator, you have
to remove the device from the pipe-
line. For this purpose, first allow the
relevant section of the plant to cool
down in the case of high tempera-
tures. Then, depressurize and drain
this section prior to removing the regu-
lator.
4.1 Cleaning and replacing the
plug
– Refer to Fig. 1 on page 4 –
Caution!
The positioning springs are pre-loaded.
Take appropriate precautionary measures: if
necessary, make a disassembly tool or use
SAMSON’s disassembly tool 9129-2747.
1. Remove regulator from the pipeline.
Unscrew control line (11).
2. Disassemble positioning springs (8).
3. Unscrew stopper (1.2).
4. Loosen body screws (7) and remove ac-
tuator.
5. Unscrew plug nut (3.1) and remove
valve plug (3) from plug stem.
6. For valve sizes DN 15 to 25, unscrew
and remove the guide nipple of the plug
(3.2) using a socket wrench (order no.
1280-3001).
For valve sizes DN 32 to 50, first re-
move screw ferrule (3.3) and then pull
out guide nipple (3.2).
7. Clean seat and plug assembly thor-
oughly. Check control line, screw con-
nections, and hole (11.1) for any block-
ages.
Should the plug be damaged, replace
the entire plug assembly.
Replace the seat if it is damaged.
To reassemble the regulator, proceed in re-
verse order.
Make sure that the diaphragm is inserted
properly in the body groove before fasten-
ing the components.
Refer to tightening torques listed in the table
in Fig. 1.
EB 3226 EN 7
Maintenance – Replacing parts

4.2 Replacing the diaphragm
– Refer to Fig. 1 on page 4 –
Caution!
The positioning springs are pre-loaded.
Take appropriate precautionary measures: if
necessary, make a disassembly tool or use
SAMSON’s disassembly tool 9129-2747.
1. Disassemble positioning springs (8).
2. Unscrew control line (11).
3. Loosen screws (7) and lift off actuator.
4. Unscrew nut (4) sealed with paint while
holding lower nut stationary.
5. Lift off diaphragm plate (5) and replace
operating diaphragm (6.1).
To reassemble, proceed in reverse order.
Make sure that the diaphragm is inserted
properly in the body groove before fasten-
ing the components.
Refer to tightening torques listed in the table
in Fig. 1.
8EB 3226 EN
Maintenance – Replacing parts

5 Troubleshooting
EB 3226 EN 9
Troubleshooting
Fault Possible cause Solution
Differential
pressure set
point is
exceeded
Valve too large for con-
trol task Recalculate the valve sizing flow coefficient, KVS, and contact SAMSON.
Seat and plug untight Remove valve, clean seat and plug. If neces-
sary, replace plug (section 4.1). Otherwise,
return the device to SAMSON for repair.
Operating diaphragm
defective Replace diaphragm (section 4.2) or return the device to SAMSON for repair.
Control line blocked Remove control line and clean it.
Differential
pressure set
point is not
reached
Valve too small for con-
trol task Check set point range and contact SAMSON.
Safety device, e.g. pres-
sure limiter, has been
triggered
Check plant, unlock safety device.
Insufficient pressure drop
across the plant Compare existing differential pressure across the plant with the plant’s drag.
Strainer blocked Drain and clean filter of the strainer.
Wrong installation of
valve Reinstall the valve in such a way that the medium flows through the valve in the direc-
tion indicated by the arrow.
Control loop
hunts Valve too large for control task Recalculate the valve sizing flow coefficient, KVS, and contact SAMSON.

6 Nameplate 7 Customer inquiries
In case of inquiries, please submit the fol-
lowing details:
4Regulator type and nominal size
4Thread or flange connection
4Model number
4Upstream and downstream pressures
4Flow rate in m3/h
4Has a strainer been installed?
4Installation diagram
10 EB 3226 EN
Nameplate
Fig. 5 · Nameplate
12
4
67
810 9
5
3
1 Model number
2 Configuration ID
3 Year of manufacture
4 Type designation
5 Nominal pressure PN or ANSI Class
6 Flow coefficient KVS or CV
7 Max. perm. temperature °C or °F
8 Set point range,
differential pressure in bar or psi
9 Max. perm. differential pressure Δp
10 Arrow indicating direction of flow