Samson 42-34 Service manual

Translation of original instructions
EB 3013 EN
Differential Pressure Regulator with Flow Limitation
Type42-34·Type42-38
Self-operated Regulators · Closing Actuator
Type 42-34 Differential Pressure Regulator Type 42-38 Differential Pressure Regulator
Edition August 2021

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. The images shown in
these instructions are for illustration purposes only. The actual product may vary.
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
([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 >
Documentation.
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 3013 EN

Contents
EB 3013 EN
1 Safety instructions and measures ................................................................1-1
1.1 Notes on possible severe personal injury ......................................................1-5
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identicationnumber .....................................................................2-2
2.3.1 Type 2423 Valve.........................................................................................2-2
2.3.2 Type2424andType2428Actuators............................................................2-2
3 Design and principle of operation ...............................................................3-1
3.1 Additionalttings........................................................................................3-4
3.1.1 Versions .....................................................................................................3-5
3.2 Technical data ............................................................................................3-6
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...........................................................................5-2
5.3 Installation..................................................................................................5-5
5.3.1 Installing the regulator.................................................................................5-6
5.4 Testing the regulator ....................................................................................5-6
5.4.1 Leak test.....................................................................................................5-7
5.4.2 Pressure test................................................................................................5-8
5.4.3 Filling the plant...........................................................................................5-9
5.4.4 Cleaning the pipeline ..................................................................................5-9
5.5 Insulation .................................................................................................5-10
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

Contents
EB 3013 EN
7 Operation..................................................................................................7-1
7.1 Adjusting the set points................................................................................7-1
7.1.1 Adjusting the differential pressure set point ...................................................7-1
7.1.2 Adjustingtheowlimitation.........................................................................7-3
7.1.3 Based on a known plant pressure drop .........................................................7-4
7.1.4 Based on an unknown plant pressure drop....................................................7-4
7.2 Pressure conditions in the plant and at the regulator.......................................7-5
7.3 Sample application .....................................................................................7-6
8 Malfunctions ..............................................................................................8-1
8.1 Troubleshooting ..........................................................................................8-1
8.2 Emergency action .......................................................................................8-3
9 Servicing....................................................................................................9-1
9.1 Preparing the valve for service work.............................................................9-6
9.2 Installing the regulator after service work ......................................................9-6
9.3 Service work...............................................................................................9-6
9.4 Replacing the actuator.................................................................................9-6
9.5 Replacing the seat and plug.........................................................................9-7
9.6 Exchanging the operating diaphragm unit in the actuator ..............................9-7
9.6.1 Type2428Actuator ....................................................................................9-7
9.6.2 Type2424Actuator ....................................................................................9-7
9.7 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 Lubricants.................................................................................................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 3013 EN 1-1
Safety instructions and measures
1 Safety instructions and measures
Intended use
TheSAMSONType42-34andType42-38Regulatorsaredesignedasdifferentialpressure
regulatorswithowlimitation.TheyconsistofaType2423ValveandaType2424Actuator
(Type42-34)oraType2428Actuator(Type42-38).Theseregulatorcomponentsaredeliv-
ered separately.
Theself-operatedregulatorsareusedtocontrolthedifferentialpressureandlimittheow
rate. They are mainly used in district heating supply networks with indirect connection and in
industrial plants to control liquids.
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
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.

1-2 EB 3013 EN
Safety instructions and measures
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. Follow the instructions given by
the plant operator.
− 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.
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.
These mounting and operating instructions deals with the standard version of the device.
Components of the device that differ to those used for the standard version described in this
documentcanbeexchangedwithothercertainSAMSONcomponents.Theresidualhazards
of these components are described in the associated mounting and operating instructions
(see documents listed under 'Referenced documentation').

EB 3013 EN 1-3
Safety instructions and measures
Safety features
TheTypes42-34and42-38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.
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.
Operatorsareadditionallyresponsibleforensuringthatthelimitsfortheproductdenedin
the technical data are observed. This also applies to the start-up and shutdown procedures.
Start-up and shutdown procedures fall within the scope of the operator's duties and, as such,
are not part of these mounting and operating instructions. SAMSON is unable to make any
statements about these procedures since the operative details (e.g. differential pressures and
temperatures) vary in each individual case and are only known to the operator.
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,directives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 3013 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.).

EB 3013 EN 1-5
Safety instructions and measures
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.
1.2 Notesonpossiblepersonalinjury
WARNING
!
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unnoticed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.
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. Follow the instructions given
by the plant operator.

1-6 EB 3013 EN
Safety instructions and measures
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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 preloaded
springs.
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.
ÎDo not start up the regulator until all parts have been mounted.
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.
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 indicat-
ed on the SAMSON delivery note.
ÎInformation on safe use of the part affected uwww.samsongroup.com/en/
about-samson/material-compliance/reach-regulation/.

EB 3013 EN 1-7
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.
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 (see information under
'Lifting the regulator' in the 'Shipment and on-site transport' section).
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thevalve.
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.

1-8 EB 3013 EN
Safety instructions and measures
NOTICE
!
Riskofleakageandregulatordamageduetoexcessivelyhighorlowtightening
torques.
Observethespeciedtorqueswhentighteningregulatorcomponents.Excessivetighten-
ing 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.
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 install 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.
SAMSON's After-sales Service can support you concerning lubricant, tightening torques
and tools approved by SAMSON.
Note

EB 3013 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
separate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
3Material number
4 Order number or date
5 KVS/CV
6 Unassigned
7Valvesize
8 Pressure rating
9 Perm. differential pressure
10 Perm. temperature
11 Body material
NameplateofType2424andType2428Actuators
DIN/ANSIversion
1Actuatorarea(DIN/ANSI)
2 Type
3 Material number and device index
4 ID number
5 Year of manufacture
6.1 Pressure rating in Pperm(DIN/ANSI)
7Valvesize(DIN/ANSI)
9Δpsetpointrange(DIN/ANSI)
DIN/ANSIversion
6.1
2341 511
7910912
10 Diaphragm material
11 CE marking
12 Certicationbodynumber
Fig.2-1: Nameplates of regulator components

2-2 EB 3013 EN
Markingsonthedevice
2.2 Location of the nameplates
Location of the
nameplate on
the regulator
components
Fig.2-2: Nameplates of the Type2423 Valve
and the Type2424 and Type2428
Diaphragm Actuators
2.3 Materialidentication
number
2.3.1 Type2423Valve
Seethenameplate(11forDIN/ANSI
version, body material) for the material
used. For more details on the nameplate, see
section2.1.
2.3.2 Type2424and
Type2428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
detailsonthenameplate,seesection2.1.

EB 3013 EN 3-1
Design and principle of operation
3 Design and principle of oper-
ation
ÎSeeFig.3-1andFig.3-2
Thedifferentialpressureregulatorswithow
limitation are designed to maintain the differ-
ential pressure between the high-pressure
andlow-pressurelinestoadenedsetpoint.
Theowratecanbelimitedbytherestriction
integrated in the valve body.
Type42-34·Thesetpointcanbeadjusted
as required within the set point range.
Type42-38·Thesetpointisxed.
The regulators basically consist of the
Type2423Valvewithseat(2),plug(3)and
restriction (1.4) as well as a closing actuator
(Type2424orType2428)withanoperating
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inthe
direction indicated by the arrow. The areas
released by the restriction (1.4) and the
valveplug(3)determinetheowrateand
thedifferentialpressure∆pplant across the
plant. See 'Pressure conditions in the plant
and at the regulator' in the 'Operation' sec-
tion.
In fully balanced valves, the forces acting on
the valve plug created by the upstream and
downstream pressures are balanced by a
balancing bellows (5) or balancing dia-
phragm (5.1). Regulators balanced by a bel-
lows or a diaphragm only differ in the pres-
sure balancing principle applied. Valves bal-
ancedbyadiaphragm(DN65to250only)
have a balancing diaphragm (5.1) instead
of the balancing bellows (5). The down-
stream pressure p2acts on the bottom of the
diaphragm and the upstream pressure p1on
the top of the diaphragm. As a result, the
forces created by the upstream and down-
stream pressures acting on the plug are bal-
anced out.
TheregulatorsinDN15to100aretted
with a connecting piece (10) for the
low-pressure control line between the valve
and actuator.
To control the differential pressure, the high
pressure(ow)oftheplantistransmitted
over the high-pressure control line to the bot-
tom diaphragm chamber of the actuator. The
pressure downstream of the restriction (1.4)
is transmitted through the hollow plug stem
and the attached low-pressure control line to
the top diaphragm chamber of the actuator.
The differential pressure is converted into a
set point force at the operating diaphragm
(13) and used to move the plug according to
the force of the set point springs (16). De-
pending on the actuator version, the set
point springs installed in the actuator
(Type42-38)denethesetpointorthe
springs are mounted externally to allow the
setpointtobeadjusted(Type42-34).
Theowsetpointscrew(1.1)withthead-
justed restriction (1.4) is used to change the
cross-sectionalareaofowtoadjustthe
maximumowrate.
The force limiter (20) and internal excess
pressure limiter (21) protect the seat and
plug from overload during exceptional oper-
ating conditions.

3-2 EB 3013 EN
Design and principle of operation
Type2423Valve,DN15to250 · Balanced by a
bellows
Type 2423 Valve
DN15to100 · Balanced by a bellows
16
17
14.2
13
15
18
19
11
12.1
10
9
8
5
7
20
21
4
1
3
2
1.2
1.4
1.1
1.3
+
_
9.1
22
14.1
12.2
24
+
_
21
18
19
16, 20
12.1
11
13
Type2424Actuator
Type42-34
Type2428Actuator
Type42-38
Fig.3-1: Functional diagram for regulators, DN15 to 250 with balancing bellows

EB 3013 EN 3-3
Design and principle of operation
Type2423Valve,DN65to100 · Balanced by a
diaphragm
Type2423Valve,DN125to250 · Balanced by a
diaphragm
1
2
3
p
1
5.1
4
1.3
1.1
1.2
1.4
p2
1
2
3
p
1
5.1
4
1.3
1.1
1.2
1.4
p2
Type2424Actuator
Type42-34
Type2428Actuator
Type42-38
Type2424Actuator
Type42-34
Type2428Actuator
Type42-38
Fig.3-2: Functional diagram for regulators, DN65 to 250 with balancing diaphragm
LegendforFig.3-1andFig.3-2
1 Valve body
1.1
Flow set point
adjustment
(set point screw)
1.2 Lock nut
1.3 Cap
1.4 Restriction
2 Seat
3 Plug
4 Plug stem
5 Balancing bellows
5.1 Balancing diaphragm
7 Spring
8
Screw plug (balanced
byabellows,DN125
and larger)
9Low-pressure control
line(uptoDN100)
9.1
Low-pressure
connection(DN125
and larger)
10 Connecting piece (up
toDN100)
11 Coupling nut
12.1 Diaphragm stem
12.2 Diaphragm stem
13 Operating diaphragm
14.1 Top diaphragm case
(valve on top)
14.2 Bottom diaphragm
case (valve on top)
15 Nuts and bolts
16 Set point springs
17
Set point adjustment
for differential
pressure (set point
adjuster)
18 Nut
19 Diaphragm plate
20 Force limiter
21 Internal excess pres-
sure valve
22 Blanking plug at side
24 Diaphragm stem

3-4 EB 3013 EN
Design and principle of operation
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 pressure reducing valve (uEB1015).
Note
3.1 Additionalttings
ÎSeeFig.3-3
Pressure gauges
Install a pressure gauge (3 and 5) at suitable
points to monitor the pressures prevailing in
the plant.
Bypassandshut-offvalves
We recommend installing a shut-off valve (1,
6) both upstream of the strainer and down-
stream of the regulator and installing a by-
pass line (18). The bypass ensures that the
plant does not need to be shut down for ser-
vice and repair work on the regulator.
M
46 95
3 721
+
–
8
18
1 Shut-off valve
2 Strainer
3Pressuregauge(ow
pipe)
4
Type42-38Differential
Pressure Regulator with Flow
Limitation
5Pressuregauge(returnow
pipe)
6 Shut-off valve
7Motorizedvalve
8 Needle valve (optional)
9 Shut-off valve (optional)
18 Bypass with capped valve
(optional)
Fig.3-3: Installation example: Type42-38 installed in the return ow pipe

EB 3013 EN 3-5
Design and principle of operation
3.1.1 Versions
Type42-34andType42-38Differential
Pressure Regulators with Flow Limitation are
designedforinstallationinthereturnow
pipe, e.g. a district heating station with indi-
rect connection.
− Type42-34 · With adjustable differential
pressureandowlimitation·Withinter-
nal overload protection (excess pressure
limiter) in the actuator
− Type42-38·Withxeddifferentialpres-
sureandadjustableowlimitation·
With internal overload protection (excess
pressure limiter) in the actuator
Regulatorcongurations
The regulators consist of a valve and an ac-
tuator with adjustable restriction. They con-
trol the differential pressure to the set point
adjustedattheactuatorandlimittheow
rate to the value adjusted at the restriction.
Type42-34withconnectingpiece(DN15to
100)
Consisting of:
Valve —Type2423,balanced
Actuator —Type2424adjustablesetpoint
Type42-38 with connecting piece
Consisting of:
Valve —Type2423,balanced
Actuator —Type2428xedsetpoint
Insulation
Regulators can be insulated to reduce heat
energy transfer.
Refer to the instructions in the 'Installation'
section.
The Type42-34 and Type42-38 Regulators
are not safety valves. If necessary, a suitable
overpressure protection must be installed on
site in the plant section.
Note

3-6 EB 3013 EN
Design and principle of operation
3.2 Technical data
The valve and actuator nameplates provide
information on the valve and actuator ver-
sions (see the 'Markings on the device' sec-
tion).
More information is available in Data Sheet
uT3013.
Conformity
TheType42-34andType42-38Regulators
bear both the CE and EAC marks of confor-
mity.
Process medium and scope of application
Thedifferentialpressureregulatorswithow
limitation are designed to maintain the dif-
ferential pressure between the high-pressure
andlow-pressurelinestoadenedsetpoint
andtolimittheowrate.
− Suitable for liquids from 5to150°C
− Max. temperature 150°C
− Differential pressure set points from 0.1
to2.5bar
− Adjustableowraterangefrom0.05 to
520m³/h
− ValvesizeDN15to250
− Pressure ratings from PN16to40
The regulator is open when relieved of pres-
sure. The valve closes when the differential
pressureorowraterises.
Note
The materials used in the regulator are also
resistant to high concentrations of glycol.
Nevertheless, glycol reacts when it comes in-
to contact with metals and causes acids to
form. We cannot prevent this reaction.
Therefore, prevent it through the use of suit-
able inhibitors.
Leakageclass
The metal-seated regulator has the leakage
classIaccordingtoIEC60534-4.
The soft-seated regulator has the leakage
classIVaccordingtoIEC60534-4.
Temperature range
Dependingonhowtheregulatoriscong-
ured, it can be used up to temperatures of
150°C/300°F(seeTable3-1).Themini-
mum temperature is limited by the accesso-
ries used and the actuator's diaphragm ma-
terial (uT3013).
Noise emissions
SAMSON is unable to make general state-
ments about noise emissions. The noise emis-
sions depend on the regulator version, plant
facilities, process medium and operating
conditions.
Dimensions and weights
Table 3-6 to Table 3-7 provide an overview
of the dimensions and weights. The lengths
and heights in the dimensional drawings are
shownonpages3-10and3-11.
Note