Samson 42-37 Service manual

Translation of original instructions
EB 3017 EN
Type42-37 Flow and Differential Pressure Regulator
Type42-39 Flow and Differential Pressure or Pressure Regulator
Self-operated Regulators
Edition August 2020

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 3017 EN
Note on this excerpt from the mounting and operating instructions
This document contains an excerpt from the mounting and operating instructions named on
the front cover. The structure of the overall document is based on the categories dened in
VDI 2770 Directive and serves to classify the documentation. The contents of this part docu-
ment apply to the category specied after the number of the mounting and operating instruc-
tions (e.g. EB xxxx followed by ‘-03-0x‘ indicating the category). The part document only
covers a restricted part of the manufacturer information available for this product.
To ensure a safe use of the product, all persons handling the product must read and under-
stand the following parts of the mounting and operating instructions before performing any
work on it:
−Section on safety instructions and measures
−Sections describing the work to be performed
ÎRefer to the overall document for any information not included in this part document.
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 3017 EN
1 Safety instructions and measures ................................................................1-1
1.1 Notes on possible severe personal injury ......................................................1-4
1.2 Notes on possible personal injury ................................................................1-5
1.3 Notes on possible property damage.............................................................1-7
2 Markings on the device ..............................................................................2-1
2.1 Nameplates................................................................................................2-1
2.2 Location of the nameplates ..........................................................................2-2
2.3 Material markings.......................................................................................2-2
2.3.1 Type 2423 Valve.........................................................................................2-2
2.3.2 Type2427 and Type2429 Actuators............................................................2-2
3 Design and principle of operation ...............................................................3-1
3.1 Additional ttings........................................................................................3-5
3.2 Technical data ............................................................................................3-7
4 Shipment and on-site transport ...................................................................4-1
4.1 Accepting the delivered goods .....................................................................4-1
4.2 Removing the packaging from the regulator ..................................................4-1
4.3 Transporting and lifting the regulator............................................................4-2
4.3.1 Transporting the regulator............................................................................4-2
4.3.2 Lifting the regulator .....................................................................................4-3
4.4 Storing the regulator ...................................................................................4-4
5 Installation.................................................................................................5-1
5.1 Installation conditions..................................................................................5-1
5.2 Preparation for installation...........................................................................5-6
5.3 Final installation..........................................................................................5-8
5.3.1 Installing the regulator.................................................................................5-8
5.3.2 Cleaning the pipeline ..................................................................................5-9
5.4 Testing the regulator ..................................................................................5-10
5.4.1 Leak test...................................................................................................5-11
5.4.2 Pressure test..............................................................................................5-11
5.5 Insulation .................................................................................................5-12
6 Start-up .....................................................................................................6-1
6.1 Start-up and putting the device back into operation .......................................6-1
6.2 Starting up the plant....................................................................................6-2
6.2.1 Regulation of liquids....................................................................................6-2
6.2.2 Regulation of steam.....................................................................................6-2

Contents
EB 3017 EN
7 Operation..................................................................................................7-1
7.1 Adjusting the set point.................................................................................7-1
7.2 Adjusting the ow set point..........................................................................7-2
7.3 Adjusting the differential pressure set point of the Type2427 Actuator
(Type42-37) ..............................................................................................7-6
7.4 Adjusting the pressure set point of the Type2429 Actuator (Type42-39).........7-6
8 Malfunctions ..............................................................................................8-1
8.1 Troubleshooting ..........................................................................................8-1
8.2 Emergency action .......................................................................................8-3
9 Servicing....................................................................................................9-1
9.1 Preparation for service work ........................................................................9-6
9.2 Installing the regulator after service work ......................................................9-6
9.3 Service work...............................................................................................9-6
9.3.1 Replacing the actuator.................................................................................9-7
9.3.2 Replacing the seat and plug.........................................................................9-7
9.3.3 Replacing the actuator's operating diaphragm ..............................................9-7
9.4 Ordering spare parts and operating supplies ................................................9-8
10 Decommissioning .....................................................................................10-1
11 Removal ..................................................................................................11-1
11.1 Removing the regulator from the pipeline....................................................11-1
11.2 Removing the actuator from the valve .........................................................11-1
12 Repairs ....................................................................................................12-1
12.1 Returning devices to SAMSON ..................................................................12-1
13 Disposal...................................................................................................13-1
14 Certicates...............................................................................................14-1
15 Annex......................................................................................................15-1
15.1 Tightening torques.....................................................................................15-1
15.2 Lubricant..................................................................................................15-1
15.3 Tools ........................................................................................................15-1
15.4 Accessories ..............................................................................................15-1
15.5 Spare parts ..............................................................................................15-2
15.6 After-sales service.....................................................................................15-8

EB 3017 EN 1-1
Safety instructions and measures
1 Safety instructions and measures
Intended use
The SAMSON Type42-37 Regulator is a ow and differential pressure regulator.
The SAMSON Type42-39 Regulator is a ow and differential pressure or pressure regulator.
They consist of a Type2423 Valve and a Type2427 Actuator (Type42-37) or a Type2429
Actuator (Type42-39). The valve and actuator (except for tested regulators) are delivered
separately and must be assembled together according to these instructions.
The self-operated regulators are used to control the ow rate and the differential pressure or
pressure in pipelines. Liquids, gases and vapors in processing and industrial plants can be
controlled by the regulator.
The regulators are designed to operate under exactly dened conditions (e.g. operating pres-
sure, process medium, temperature). Therefore, operators must ensure that the regulators are
only used in operating conditions that meet the specications used for sizing the devices at
the ordering stage. In case operators intend to use the regulators in other applications or
conditions than specied, contact SAMSON.
SAMSON does not assume any liability for damage resulting from the failure to use the de-
vice for its intended purpose or for damage caused by external forces or any other external
factors.
ÎRefer to the technical data and nameplate for limits and elds of application as well as
possible uses.
Reasonably foreseeable misuse
The regulators are not suitable for the following applications:
−Use outside the limits dened during sizing and by the technical data
−Use outside the limits dened by the additional ttings mounted on the regulator
Furthermore, the following activities do not comply with the intended use:
−Use of non-original spare parts
−Performing service and repair work not described
Safety features
The Types42-37 and 42-39 Regulators do not have any special safety features. When re-
lieved of pressure, the regulators are opened by the force of the set point springs.

1-2 EB 3017 EN
Safety instructions and measures
Qualications of operating personnel
The regulator must be mounted, started up, serviced and repaired by fully trained and quali-
ed personnel only; the accepted industry codes and practices must be 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 hazards due to their spe-
cialized training, their knowledge and experience as well as their knowledge of the applica-
ble standards.
Personal protective equipment
We recommend checking the hazards posed by the process medium being used (e.g.
uGESTIS (CLP) hazardous substances database). Depending on the process medium and/
or the activity, the protective equipment required includes:
−Protective clothing, safety gloves and eye protection in applications with hot, cold and/or
corrosive media
−Wear hearing protection when working near the valve
−Hard hat
−Safety harness when working at height
−Safety footwear, ESD (electrostatic discharge) footwear, if necessary
ÎCheck with the plant operator for details on further protective equipment.
Revisions and other modications
Revisions, conversions or other modications of the product are not authorized by SAMSON.
They are performed at the user's own risk and may lead to safety hazards, for example. Fur-
thermore, the product may no longer meet the requirements for its intended use.
Responsibilities of the operator
Operators are responsible for proper use and compliance with the safety regulations. Opera-
tors are obliged to provide these mounting and operating instructions as well as the refer-
enced documents to the operating personnel and to instruct them in proper operation. Fur-
thermore, operators must ensure that operating personnel or third parties are not exposed to
any danger.

EB 3017 EN 1-3
Safety instructions and measures
Warning against residual hazards
To avoid personal injury or property damage, plant operators and operating personnel must
prevent hazards that could be caused in the regulator by the process medium, the operating
pressure or by moving parts by taking appropriate precautions. Plant operators and operat-
ing personnel must observe all hazard statements, warning and caution notes in these
mounting and operating instructions.
Hazards resulting from the special working conditions at the installation site of the regulator
must be identied in a risk assessment and prevented through the corresponding safety in-
structions drawn up by the operator.
We also recommend checking the hazards posed by the process medium being used (e.g.
uGESTIS (CLP) hazardous substances database).
ÎObserve safety measures for handling the device as well as re prevention and explosion
protection measures.
Responsibilities of operating personnel
Operating personnel must read and understand these mounting and operating instructions as
well as the referenced documents and observe the specied hazard statements, warnings
and caution notes. Furthermore, operating personnel must be familiar with the applicable
health, safety and accident prevention regulations and comply with them.
Referenced standards and regulations
The regulators comply with the requirements of the European Pressure Equipment Directive
2014/68/EU. Regulators with a CE marking have an EU declaration of conformity, which
includes information about the applied conformity assessment procedure. This EU declaration
of conformity is included in the 'Certicates' section.
According to the ignition risk assessment performed in accordance with EN13463-1:2009,
section 5.2, the non-electrical regulators do not have their own potential ignition source even
in the rare incident of an operating fault. As a result, they do not fall within the scope of Di-
rective 2014/34/EU.
ÎFor connection to the equipotential bonding system, observe the requirements specied in
section6.4 of EN60079-14 (VDE0165-1).

1-4 EB 3017 EN
Safety instructions and measures
Referenced documentation
The following documents apply in addition to these mounting and operating instructions:
−Mounting and operating instructions for
e.g. Type2N/NI Strainer uEB1015
−Data sheets for
e.g. Accessories · Differential pressure and ow regulators uT3095
e.g. Type2N/NI Strainer uT1015
−Mounting and operating instructions as well as data sheets for additional ttings
(e.g. shut-off valves, pressure gauges etc.).
1.1 Notes on possible severe personal injury
DANGER
!
Risk of bursting in pressure equipment.
Regulators and pipelines are pressure equipment. Impermissible pressure or improper
opening can lead to regulator components bursting.
ÎObserve the maximum permissible pressure for regulator and plant.
ÎIf necessary, a suitable overpressure protection must be installed on site in the plant
section.
ÎBefore starting any work on the regulator, depressurize all plant sections affected
as well as the regulator.
ÎDrain the process medium from all the plant sections affected as well as the regula-
tor.
ÎWear personal protective equipment.

EB 3017 EN 1-5
Safety instructions and measures
1.2 Notes on possible personal injury
WARNING
!
Crush hazard arising from moving parts.
The regulator contains moving parts (set point springs), which can injure hands or n-
gers if inserted into the regulator.
ÎDo not insert hands or ngers between the set point springs while the regulator is
in operation.
ÎBefore performing any work on the regulator, depressurize the plant. Disconnect or
shut off the control line.
Risk of personal injury due to pressurized components and process medium being
discharged.
Incorrect opening of pressure equipment or mounting parts may lead to the process
medium escaping to the atmosphere.
ÎDo not loosen the control line while the valve is pressurized.
Risk of personal injury due to loaded springs.
The set point springs of regulators with adjusted set point are preloaded and are under
tension.
ÎBefore starting any work on the springs, relieve the compression from the preload-
ed springs.
Risk of hearing loss or deafness due to loud noise.
The noise emissions depend on the valve version, plant facilities and process medium.
ÎWear hearing protection when working near the valve.
Risk of burn injuries due to hot or cold components and pipelines.
Depending on the process medium, regulator components and pipelines may get very
hot or cold and cause burn injuries.
ÎAllow components and pipelines to cool down or warm up to the ambient tempera-
ture.
ÎWear protective clothing and safety gloves.

1-6 EB 3017 EN
Safety instructions and measures
WARNING
!
Risk of personal injury due to residual process medium in the regulator.
While working on the regulator, residual process medium can escape and, depending
on its properties, may lead to personal injury, e.g. (chemical) burns.
ÎIf possible, drain the process medium from all the plant sections affected and the
regulator.
ÎWear protective clothing, safety gloves and eye protection.
Damage to health relating to the REACH regulation.
If a SAMSON device contains a substance which is listed as being a substance of very
high concern on the candidate list of the REACH regulation, this circumstance is indi-
cated on the SAMSON delivery note.
ÎInformation on safe use of the part affected uwww.samsongroup.com/en/
about-samson/material-compliance/reach-regulation/
Risk of personal injury due to process medium escaping after an operating dia-
phragm/bellows rupture.
When using the Type42-39 Regulator as a pressure regulator, residual process medi-
um can escape after a rupture of the operating diaphragm and, depending on its
properties, lead to personal injury, e.g. (chemical) burns.
ÎDepressurize plant sections concerned.
ÎWear protective clothing, safety gloves and eye protection.
Risk of personal injury through incorrect operation, use or installation as a result of
information on the regulator being illegible.
Over time, markings, labels and nameplates on the regulator may become covered
with dirt or become illegible in some other way. As a result, hazards may go unno-
ticed and the necessary instructions not followed. There is a risk of personal injury.
ÎKeep all relevant markings and inscriptions on the device in a constantly legible
state.
ÎImmediately renew damaged, missing or incorrect nameplates or labels.

EB 3017 EN 1-7
Safety instructions and measures
1.3 Notes on possible property damage
NOTICE
!
Risk of regulator damage due to incorrectly attached slings.
ÎDo not attach load-bearing slings to the actuator housing.
Risk of regulator damage due to unsuitable medium properties.
The regulator is designed for a process medium with dened properties.
ÎOnly use the process medium specied for sizing.
Risk of regulator damage due to contamination (e.g. solid particles) in the pipeline.
The plant operator is responsible for cleaning the pipelines in the plant.
ÎFlush the pipelines before start-up.
Risk of regulator damage due to the use of unsuitable lubricants.
The lubricants to be used depend on the regulator material. Unsuitable lubricants may
corrode and damage surfaces.
ÎOnly use lubricants approved by SAMSON.
When in doubt, consult SAMSON.
Risk of leakage and regulator damage due to excessively high or low tightening
torques.
Observe the specied torques when tightening regulator components. Excessive tight-
ening torques lead to parts wearing out more quickly. Parts that are too loose may
cause leakage.
ÎObserve the specied tightening torques (see 'Tightening torques' in Annex).
Risk of regulator damage due to the use of unsuitable tools.
Certain tools are required to work on the regulator.
ÎOnly use tools approved by SAMSON.
When in doubt, consult SAMSON.

1-8 EB 3017 EN
Safety instructions and measures
NOTICE
!
Risk of the process medium being contaminated through the use of unsuitable lubri-
cants and/or contaminated tools and components.
ÎKeep the regulator and the tools used free from solvents and grease.
ÎMake sure that only suitable lubricants are used.
Risk of excess pressure damaging plant sections due to construction-related seat
leakage through the regulator.
ÎAlways t a safety device (e.g. safety excess pressure valve or safety relief valve) in
the plant.
Incorrect control due to the formation of ice on the regulator.
Medium temperatures below 0°C may cause ice to form on the regulator, depending
on the air humidity. This may affect, in particular, the functioning of the plug or dia-
phragm stem guide.
ÎPrevent the formation of ice by taking appropriate precautions (e.g. enclosure,
trace heater etc.). The plant operator is responsible for selecting and implementing
appropriate precautions. See the 'Installation' section.
Risk of damage due to process medium escaping after an operating diaphragm rup-
ture.
When using the Type42-39 Regulator as a pressure regulator, residual process medi-
um can escape after a rupture of the operating diaphragm and, depending on its
properties, lead to device damage or peripheral damage.
ÎWhen a regulator is tted with a leakage line connection, discharge any vapors or
gases that escape through a leakage line to the atmosphere and in a safe place.
ÎCatch any liquids or gases that escape and may be harmful to the environment in
a tank. Dispose of them in accordance with the applicable regulations.
SAMSON's After-sales Service can support you concerning lubricant, tightening torques
and tools approved by SAMSON.
Note

EB 3017 EN 2-1
Markings on the device
2 Markings on the device
Several nameplates are afxed to the device. The nameplates are used to identify the sepa-
rate regulator components (see section2.1).
2.1 Nameplates
Nameplates of Type2423 Valve
DIN version ANSI version
2314 5
11109876
2314 5
11109876
ANSI version · DIN version
1 Valve type
2 Model number with index
3 Material number
4Order number or date
5 KVS/CV
6Set point range or spring
range
7Valve size
8 Pressure rating
9Perm. differential pressure
10 Perm. temperature
11 Body material
Nameplate of Type2427 Actuator
DIN/ANSI version
1Actuator area (DIN/ANSI)
2 Type
3 Material number and device index
4 ID number
5Year when the CE certication was
issued
6.1 Pressure rating in PN/Class (DIN/
ANSI)
7Valve size (DIN/ANSI)
9Differential pressure across the
restriction (DIN/ANSI)
10 Diaphragm material
11 CE marking
12 Certication body number
DIN/ANSI version
6.1
2341 511
7910912
Fig.2-1: Nameplates of regulator components

2-2 EB 3017 EN
Markings on the device
2.2 Location of the nameplates
Location of the
nameplate on the
regulator
components
Fig.2-2: Sample nameplates of the Type2423
Valve and the Type2427 Diaphragm
Actuator
2.3 Material markings
2.3.1 Type 2423 Valve
See the nameplate (11 for DIN/ANSI ver-
sion, body material). For more details on the
nameplate, see section2.1.
2.3.2 Type2427 and
Type2429 Actuators
Specifying the material number, you can
contact us to nd out which material is used.
This is specied on the nameplate in the
'MNo.' eld (3 for DIN/ANSI). For more de-
tails on the nameplate, see section2.1.

EB 3017 EN 3-1
Design and principle of operation
3 Design and principle of oper-
ation
ÎSee Fig.3-1 to Fig.3-3
The regulators restrict the ow rate in the
pipeline to a set point adjusted at the restric-
tion. The set point for the differential pressure
or downstream pressure is adjusted at the di-
aphragm actuator. The largest signal is al-
ways used to control the regulator.
The regulators basically consist of a
Type2423 Valve with seat, plug and restric-
tion as well as a closing actuator (Type2427
or Type 2429) with an operating dia-
phragm. Valve and actuator are delivered
separately and must be assembled on site
using a coupling nut.
The medium ows through the valve in the
direction indicated by the arrow. The areas
released by the restriction (1.1) and the plug
(3) determine the ow rate and the differen-
tial pressure ∆p across the plant.
In balanced valves, the forces acting on the
plug created by the upstream and down-
stream pressures are balanced by a balanc-
ing bellows (5) or balancing diaphragm (5.1,
balanced by a diaphragm, DN65 to 250).
Regulators balanced by a bellows or a dia-
phragm only differ in the pressure balancing
principle applied. Valves balanced by a dia-
phragm have a balancing diaphragm (5.1)
instead of the balancing bellows (5). The
downstream pressure p2acts on the bottom
of the diaphragm and the upstream pressure
p1on the top of the diaphragm. In both cas-
es, the forces created by the upstream and
downstream pressures that act on the plug
are balanced out.
Type42-37: The high pressure of ∆p acts on
the bottom diaphragm chamber Dover the
control line (18). The high pressure of the
ow rate upstream of the restriction (1.1) is
transferred over the control line (19) to the
middle diaphragm chamber Band C. It is the
same as the low pressure of ∆p. The low
pressure of
V
downstream of the restriction is
transferred over holes in the plug and dia-
phragm stems to the top diaphragm chamber
A.
For example, if the differential pressure rises,
the resulting positioning force at the bottom
operating diaphragm (13.2) rises as well.
The diaphragm stems (12.1 and 12.2) push
the plug stem with plug in the closing direc-
tion until the ow rate reaches the set point
adjusted at the set point spring (16).
If the ow rate increases, the differential pres-
sure at the restriction (1.1) and the resulting
positioning force at the top operating dia-
phragm (13.1) increase. The top diaphragm
stem (12.1) pushes the plug stem with plug in
the closing direction until the ow rate reach-
es the adjusted ow set point. The largest sig-
nal is always used to move the plug.
An overload protection (force limiter with in-
ternal excess pressure limiter) (15) protects
the seat (2), plug (3) and plant from over-
load during exceptional operating condi-
tions.
Type42-37: The principle of operation is al-
most the same as for Type42-37. However,
in the Type2429 Actuator, the high pressure
of the ow rate is separate from the low
pressure of the differential pressure ∆p. The
diaphragm chambers have their own control
line connections.

3-2 EB 3017 EN
Design and principle of operation
1
1.2
1.3
1.1
2
3
4
19
18
21
B
A
C
D
V{
{
{
{
8
5
7
12.1
9
13.1
13.2
15
12.2
16
17
11
1.4
Type2423 Valve
balanced by a bellows
Type2427
Actuator
Fig.3-1: Functional diagram of Type42-37 Regulator, DN15 to 250 with balancing bellows

EB 3017 EN 3-3
Design and principle of operation
19 20
18
B
A
C
D
V
21
{
{
{
{
22
Type2423 Valve
balanced by a bellows
Type2429
Actuator
Fig.3-2: Functional diagram of Type42-39 Regulator, DN15 to 250 with balancing bellows

3-4 EB 3017 EN
Design and principle of operation
1.3
1.4
p1
18
p
2
1.2
1
4
5.1
3
2
1.1
Type2423 Valve
balanced by a diaphragm
Type2427 Actuator for Type42-37 or
Type2429 Actuator for Type42-39
Fig.3-3: Functional diagram of Type2423 Valve, DN65 to 250 with balancing diaphragm
Legend for Fig.3-1 to Fig.3-3
1 Valve body
1.1 Restriction
1.2 Lock nut
1.3 Cap
1.4 Set point adjuster (ow rate)
2 Seat
3 Plug
4 Plug stem
5 Balancing bellows
5.1 Balancing diaphragm
7 Spring
8Vent plug (DN125 and larger)
9Differential pressure spring
11 Coupling nut
12.1 Top diaphragm stem
12.2 Bottom diaphragm stem
13.1 Top operating diaphragm
13.2 Bottom operating diaphragm
15 Overload protection
16 Set point spring
17 Set point adjuster (differential
pressure)
18 Control line (to be provided on
site)
19 Control line (+) V
20 Control line (+) ∆p
21 Restriction to dampen signal
22 Set point adjuster (pressure)
.

EB 3017 EN 3-5
Design and principle of operation
3.1 Additional ttings
ÎSee Fig.3-4
Pressure gauges
Install a pressure gauge (3 and 6) at a suit-
able point to monitor the pressures prevail-
ing in the plant.
Bypass and shut-off valves
We recommend installing a shut-off valve (1
and 9) both upstream of the strainer and
downstream of the regulator to ensure that
the entire plant does not need to be shut
down for service or repair work. An optional
bypass (7) can be used to achieve the maxi-
mum ow rate during regulator start-up
when adjusting the ow set point.
Strainers
We recommend installing a SAMSON
strainer (2) upstream of the valve. It prevents
solid particles in the process medium from
damaging the regulator.
ÎDo not use the strainer to permanently
lter the process medium.
ÎSelect a strainer (mesh size) suitable for
the process medium.
Any impurities carried along by the process
medium may impair the proper functioning
of the regulator. We recommend installing a
strainer (e.g. SAMSON Type2NI) upstream
of the regulator (uEB1015).
Note
Insulation
Regulators can be insulated to reduce heat
energy transfer.
Refer to the instructions in the 'Installation'
section.
The Type42-37 and Type42-39 Regulators
are not safety valves. If necessary, a suitable
overpressure protection must be installed on
site in the plant section.
Note

3-6 EB 3017 EN
Design and principle of operation
Sample application (Type42-37):
1 Shut-off valve
2 Strainer
3 Pressure gauge
4Flow and differential pressure or pressure
regulator
5 Needle valve
6 Pressure gauge
7 Bypass with capped valve (recommended)
8 Shut-off valve
9Shut-off valve
10 Motorized valve
18 Compensation chamber (optional)
9
V–
+
–
+
584 6
31 2 18
.
7
10
Type42-37 in the return ow pipe
Differential pressure and ow
control:
Type42-39 in the ow pipe
Differential pressure and ow
control:
Type42-39 in the ow
pipe
Flow and pressure control:
V–
+
–
+
3
.
7
V–
+
–
+
3
.
7
V–
++
4
.
7
∆pmin Minimum differential pressure across the valve in bar
∆prestriction Differential pressure created at the restriction for measuring the ow rate in the regulator
V Adjusted ow rate in m³/h
KVS Valve ow coefcient in m³/h
·
The minimum required plant differential pressure
∆pmin across the valve is calculated as follows: Δpmin = Δprestriction +
(
V
)
2
KVS
·
Fig.3-4: Installation example: Type42-37 and Type42-39 installed in the ow or return ow pipe