Samson 42-24 Service manual

Mounting and
Operating Instructions
EB 3003 EN
Edition July 2015
Self-operated Pressure Regulators
Differential Pressure Regulators (closing)
Type42-24·Type42-28
Type42-24 Differential Pressure Regulator Type42-28A Differential Pressure Regulator

Denition of signal words
DANGER!
Hazardous situations which, if not
avoided, will result in death or seri-
ous injury
WARNING!
Hazardous situations which, if not
avoided, could result in death or seri-
ous injury
NOTICE
Property damage message or mal-
function
Note:
Additional information
Tip:
Recommended action

2 EB 3003 EN

Contents
EB 3003 EN 3
1 General safety instructions.............................................................................4
2 Process medium and scope of application.......................................................5
3 Transportation and storage............................................................................5
4 Design and principle of operation ..................................................................6
5 Installation....................................................................................................9
5.1 Mounting position..........................................................................................9
5.2 Strainer (lter)..............................................................................................10
5.3 Shut-off valve...............................................................................................10
5.4 Pressure gauge ............................................................................................10
5.5 Control line, compensation chamber and needle valve....................................11
6 Operation...................................................................................................12
6.1 Start-up.......................................................................................................12
6.2 Adjusting the set point..................................................................................12
6.3 Decommissioning.........................................................................................12
7 Maintenance and troubleshooting ................................................................13
7.1 Replacing the operating diaphragm ..............................................................15
8 Customer inquiries ......................................................................................15
9 Nameplate..................................................................................................16
10 Appendix....................................................................................................17
10.1 Technical data .............................................................................................17
10.2 Dimensions..................................................................................................20

4 EB 3003 EN
General safety instructions
1 General safety instructions
−All safety instructions and warnings given in these mounting and operating instructions,
particularly those concerning installation, start-up and maintenance, must be strictly ob-
served.
−The device must be mounted, started up or serviced by fully trained and qualied person-
nel only; the accepted industry codes and practices are to be observed. Make sure em-
ployees or third persons are not exposed to any danger.
−According to these mounting and operating instructions, trained personnel refers to indi-
viduals who are able to judge the work they are assigned to and recognize possible dan-
gers 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 a declaration of conformity, which includes
information about the applied conformity assessment procedure.This declaration of conformi-
ty can be provided on request. This declaration of conformity can be provided on request.
−To ensure appropriate use, only use the device in applications where the operating pres-
sure and temperatures do not exceed the specications used for sizing the device 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 appropriate precautions.
−Proper transport, storage, installation, operation and maintenance are assumed.
Note:
Non-electric valve versions whose bodies are not lined with an insulating material
coating do not have their own potential ignition source according to the risk assess-
ment stipulated in EN13463-1:2009, 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.
For connection to the equipotential bonding system, observe the requirements speci-
ed in section 6.3 of EN60079-14: 2011 (VDE0165 Part 1).


EB 3003 EN 5
Process medium and scope of application
2 Process medium and scope of application
Differential pressure regulators for district heating systems, extended heating systems and in-
dustrial applications
Differential pressure set points Δp from 0.05 to 10bar · Valves DN15 to 250 · Nominal
pressure PN16 to 40 · Suitable for liquids and vapors from 5 to 350°C as well as for air
and non-ammable gases up to 80°C
The valve closes when the differential pressure rises.
3 Transportation and storage
The regulator must be carefully handled, transported and stored. Protect the regulator against
adverse inuences, such as dirt, moisture or frost, during storage and transportation.
Note:
Before installing the regulator, tighten the blanking plug(s) at the side in the valve
body using a suitable box wrench.
Torque: 50Nm for G¼, 70Nm for G
3
/
8
When regulators are too heavy to be lifted by hand, fasten the lifting sling to a suitable place
on the valve body.
WARNING!
Incorrectly attached lifting slings or supports.
Risk of injury and property damage due to valve falling.
Securely fasten slings or supports to the valve body and secure against slipping.
WARNING!
Do not attach lifting slings or supports to mounting parts, such as control line etc.
The valve can fall or mounting parts may be damaged.
Securely fasten slings or supports to the body of the valve and secure against slip-
ping.


6 EB 3003 EN
Design and principle of operation
Regulator congurations
Regulator =Valve +Actuator
Type42-24 Type2422 balanced Type2424 adjustable set point
Type42-28 Type2422 balanced Type2428 xed set point
__
1) Type2422 Valve, balanced by a diaphragm, DN65 to 250 only
4 Design and principle of oper-
ation
See Fig.1 on page7.
The differential pressure regulators are de-
signed to maintain a constant pressure differ-
ence between the high pressure and low
pressure lines to an adjustable set point
(Type42-24) or a xed set point (Type42-
28).
The regulators basically consist of a valve
with seat (2) and plug (3) and a closing ac-
tuator (Type2424 or Type 2428) with an op-
erating diaphragm (13).
Valve and actuator are delivered separately
and must be assembled on site using a cou-
pling nut (11).
The medium ows through the valve between
the plug (3) and the seat (2) in the direction
indicated by the arrow. The position of the
valve plug determines the differential pres-
sure prevailing across the plant.
The Type2422 Valve is balanced. The forces
acting on the valve plug created by the up-
stream and downstream pressures are bal-
anced by a balancing bellows (5) or balanc-
ing diaphragm 1) (5.1).
The principle of operation of the regulator
balanced by a bellows or diaphragm only
differs concerning the pressure balancing.
Valves balanced by a diaphragm have a
balancing diaphragm (5.1) instead of the
balancing bellows (5). The downstream pres-
sure p2 acts on the bottom of the diaphragm
and the upstream pressure p1 on the top of
the diaphragm. As a result, the forces creat-
ed by the upstream and downstream pres-
sures acting on the plug are balanced out.
1Valve body
2 Seat
3Plug
4 Plug stem
5Balancing bellows
5.1 Balancing diaphragm (DN65 to 250)
11 Coupling nut
12 Diaphragm stem
13 Operating diaphragm
14 Diaphragm case
15 Nuts and bolts
16 Set point springs
17 Set point adjuster (set point nut)
18 Nut
19 Diaphragm plate
20 Control line
21 Overload protection (force limiter with
internal excess pressure limiter)

EB 3003 EN 7
Design and principle of operation
Fig.1: Functional diagrams of Type42-24 and Type42-28
Type42-24 Type42-28
2
3
4
5.1
P1P2
2
1
3
4
5
11
21
13
15
16
17
20
20
19
18
14
12
+
_
P1P2
4
16
13
21
20
20
+
_
12
15
11
19
18
Type42-24
Type2428 Actuator
Type2424 Actuator
Type2422 Valve, balanced by a diaphragm
(DN65 to 250)
Type2424 Actuator
Type2422 Valve, balanced by a bellows
(DN15 to 250)

8 EB 3003 EN
Design and principle of operation
The differential pressure across the plant is
transmitted over the high pressure and low
pressure lines to the operating diaphragm
(13) where it is converted into a positioning
force. This force moves the plug according to
the force of the set point springs (16).
The set point springs are mounted inside the
actuator for a xed set point (Type42-28).
These springs can be adjusted externally for
an adjustable set point (Type42-24).
Control lines (20) mounted on site transfer
the high pressure and low pressure in all ver-
sions.
Type2424 and Type2428 Actuators are
equipped with an overload protection (21). It
prevents a rise in differential pressure during
extreme operating conditions (e.g. vacuum
at the heat exchanger) by opening an inter-
nal excess pressure limiter. As a result, plants
and the regulator itself are protected against
excessively high differential pressures.

EB 3003 EN 9
Installation
5 Installation
The Type42-24 and Type42-28 Regulators
are designed for installation in the high
pressure (ow) line of the plant.
The Type42-24 and Type42-28 Regulators
are designed for installation in the low pres-
sure (return ow) line of the plant.
ÎChoose a place of installation that allows
you to freely access the regulator even af-
ter the entire plant has been completed.
ÎInstall a strainer (e.g. SAMSON
Type2N) upstream of the regulator (see
section5.2).
ÎFlush the pipeline thoroughly before in-
stalling the regulator to ensure that any
sealing parts, weld spatter and other im-
purities carried along by the process me-
dium do not impair the proper function-
ing of the valve, above all the tight shut-
off.
ÎThe direction of ow must match the di-
rection indicated by the arrow on the
body.
NOTICE
Incorrectly installed regulator
The pressure regulator can be dam-
aged.
−Make sure the regulator is installed
free of stress.
−Do not attach supports (if required)
directly to the valve or actuator. At-
tach the supports near to the con-
necting anges.
−Observe permissible mounting po-
sition.
5.1 Mounting position
See Fig.1 on page7.
See Fig.2 for permissible mounting positions.
Standard mounting position · Install valve
without actuator in a horizontal pipeline with
the connection for the actuator facing down-
wards. Make sure the medium ows through
the valve in the direction indicated by the ar-
row.
Fig.2: Permissible mounting positions
Connect the actuator to the valve bottom sec-
tion using the coupling nut (11).
Balanced by a bellows or
diaphragm
−Standard mounting position
All versions
Balanced by a bellows
−Above 80°C
−Steam applications
Balanced by a bellows
−All versions DN15 to 80
plus up to max. 80°C
Balanced by a diaphragm
−All versions up to max. 80°C
Balanced by a bellows
−Versions with xed plug
guide

10 EB 3003 EN
Installation
SW 13
Valve bottom
section
Screw plug
Do not remove!
Plug stem
DN125 to 250 only
Fig.3: Valve bottom section with plug stem
5.2 Strainer (lter)
Install the strainer upstream of the regulator.
The direction of ow must correspond to the
arrow on the body. The lter element must
be installed to hang downwards or sideways
for applications with steam. Remember to
leave enough space to remove the lter ele-
ment.
5.3 Shut-off valve
Install a hand-operated shut-off valve both
upstream of the strainer and at the outlet of
the return ow pipe (see Fig.4). This allows
the plant to be shut down for cleaning and
maintenance, and when the plant is not used
for longer periods of time.
5.4 Pressure gauge
Install a pressure gauge both upstream and
downstream of the regulator to monitor the
pressures prevailing in the plant. Install the
pressure gauge on the downstream side be-
hind the downstream pressure tapping point
(not between the tapping point and the
valve).
Fig.4: Typical installations (control lines to be installed on site are represented by a dashed line)
1
1
2237
M
7
M
4
5
6
651
1
3
6
6
4
5
5
(+) (+)
(–)
(–)
Type42-24/42-28 in a ow pipe Type42-24/42-28 in a return ow pipe
1Shut-off valve
2 Strainer
3Differential pressure regulator
4 Compensation chamber (e.g. for steam applications)
5Pressure gauge
6Needle valve (optional)
7Motorized valve