Burkert 2933 User manual

Operating Instructions
Bedienungsanleitung
Manuel d‘utilisation
Type 2933, 2934, 2935, 2973, 2974, 2975
Manually operated diaphragm valves

We reserve the right to make technical changes without notice.
Technische Änderungen vorbehalten.
Sous réserve de modifications techniques.
© Bürkert Werke GmbH & Co. KG, 2023
Operating Instructions 2304/00_EU-ML_00815442 / Original DE

3
Table of contents
1 OPERATING INSTRUCTIONS............................................... 4
1.1 Symbols....................................................................... 4
1.2 Denitionofterms ....................................................... 4
2 INTENDED USE .................................................................... 5
3 BASIC SAFETY INSTRUCTIONS.......................................... 5
4 GENERAL NOTES................................................................. 7
4.1 Contact addresses ...................................................... 7
4.2 Warranty ...................................................................... 7
4.3 InformationontheInternet.......................................... 7
5 PRODUCT DESCRIPTION .................................................... 7
5.1 Structure and description............................................ 7
5.2 Variants........................................................................ 7
5.3 Function....................................................................... 8
5.4 Productidentication .................................................. 9
6 TECHNICAL DATA............................................................... 11
6.1 Standards and directives........................................... 11
6.2 Mechanical data ........................................................ 11
6.3 Port connections valve body..................................... 12
6.4 Operating conditions ................................................. 12
6.5 Flow values................................................................ 14
7 INSTALLATION .................................................................... 16
7.1 Informationforthecorrectinstallationposition......... 17
7.2 Preparatory work ....................................................... 18
7.3 Install device.............................................................. 19
7.4 Set stroke limit........................................................... 20
7.5 Lock handwheel ........................................................ 21
8 MAINTENANCE................................................................... 22
8.1 Cleaning .................................................................... 22
8.2 Maintenance work ..................................................... 23
8.3 Replacing the diaphragm .......................................... 23
9 REPLACEMENT PARTS, ACCESSORIES .......................... 25
9.1 Replacement diaphragms ......................................... 26
10 TRANSPORTATION, STORAGE, DISPOSAL ...................... 27
english
Type 2933, 2934, 2935, 2973,
2974, 2975

4
Operating instructions
1 OPERATING INSTRUCTIONS
Theoperatinginstructionsdescribetheentirelifecycleofthedevice.
Keep these instructions ready to hand at the operating site.
Important safety information.
▶Readtheseinstructionscarefully.
▶Aboveall,observethesafetyinstructions, intendeduseand
operating conditions.
▶Persons who work on the device must read and understand
these instructions.
1.1 Symbols
DANGER
Warning of an immediate danger.
▶Failure to comply will result in death or serious injury.
WARNING
Warns of a potential danger.
▶Failure to observe these warnings may result in serious injuries
or death.
CAUTION
Warns of a potential hazard.
▶Failure to comply with these instructions may result in moderate
or minor injury.
NOTE
Warns of damage.
Important tips and recommendations.
Referstoinformationintheseoperatinginstructionsorin
other documentation.
▶Highlights instructions to avoid a danger.
→Designates a procedure which you must carry out.
1.2 Denition of terms
Term Denition for these instructions
Device Diaphragm valve type 2933, 2934, 2935,
2973, 2974 and 2975
Ex area Potentially explosive atmosphere
Explosion protection
approval
Approval in potentially explosive
atmosphere
english
Type 2933, 2934, 2935, 2973,
2974, 2975

5
Intended use
2 INTENDED USE
The diaphragm valve type 2933, 2934, 2935, 2973, 2974 and
2975 is designed to control the ow of media. The authorised
media are listed in chapter “Technical data”.
▶Use the device only as intended. Non-intended use of the
device may be dangerous to people, nearby equipment and
the environment.
▶Prerequisites for safe and trouble-free operation are correct
transportation, correct storage, installation, start-up, operation
and maintenance.
▶To use the device, observe the permitted data, operating con-
ditionsandapplicationconditions. Thesespecications can
befoundinthecontractdocuments,theoperatinginstructions
and on the Type label.
▶Use the device only in conjunction with third-party devices and
components recommended or approved by Bürkert.
▶Onlyuseequipmentthatisapprovedforthistypeofpotentially
explosivearea.Thesedevicesareidentiedbyaseparate“Ex”
typelabel.Beforeuse,notetheinformationontheseparateEx
type label and the Ex additional instructions or the separate Ex
operating Instructions.
▶Protectdevicefromenvironmentalinuences(e.g.radiation,
airhumidity,fumes).Ifyouhaveanyquestions,contactyour
Bürkert sales department.
3 BASIC SAFETY INSTRUCTIONS
Thesesafetyinstructionsdonottakeintoaccountanyunforeseen
circumstances or events that occur during installation, operation
and maintenance. The operator is responsible for observing
the location-specic safety regulations, also with reference to
personnel.
Risk of injury due to high pressure and escaping medium.
▶Switchothepressurebeforeworkingonthedeviceorsystem.
Vent or empty the lines.
Electric shock due to installed electrical component.
▶Beforeworkingonthedeviceorsystem,switchothepower
supply. Secure against reactivation.
▶Observe any applicable accident prevention regulations and
safetyregulationsforelectricaldevices.
Danger of bursting in case of overpressure.
Ifthedevicebursts, themediummaycauseinjuries, burnsor
scalds.
▶Do not exceed the maximum medium pressure. Observe spec-
icationsonthetypelabel.
▶Observe allowable temperatures.
Danger of burns and risk of re.
Quicklyswitchingactuatorsorhotmediummaycausethesurface
ofthedevicetobecomehot.
▶Only touch the device when wearing protective gloves.
▶Keepthedeviceawayfromhighlyammablesubstancesand
media.
english
Type 2933, 2934, 2935, 2973,
2974, 2975

6
Basic safety instructions
Medium may leak out if the diaphragm is worn.
▶Inspectreliefboreforanymediumleakages.
▶Changethediaphragmifmediumleaks.
▶Ifthemediumishazardous,securetheareaaroundtheleakage
to prevent risks.
Danger of crushing due to mechanically moving parts.
Thereisariskofcrushingduetotheupanddownmovement
ofthedevicewhenitisactuated.
▶Donotreachintotheopeningsofthevalvebody.
Danger due to loud noises.
Depending on the operating conditions, the device may generate
loudnoises.Moredetailedinformationonthelikelihoodofloud
noisesisavailablefromtherelevantsalesoce.
▶Wearhearingprotectionwheninthevicinityofthedevice.
To avoid injury, observe the following:
▶Do not make any changes to the device and do not subject it
to mechanical stress.
▶Onlytrainedtechniciansmayperforminstallation andmain-
tenance work.
▶Onlyusesuitabletoolstoperforminstallationandmaintenance
work.
▶Heavy equipment must only be transported, assembled and
disassembledwiththehelpofasecondpersonasappropriate
and using suitable apparatus.
▶Only hand-tighten the valve when closing. Too much tightening
may damage the diaphragm.
▶Theprocessmustberestartedinadenedorcontrolledmanner
afteraninterruptioninthepowersupplyorpneumaticsupply.
▶Thedevicemaybeoperatedonlywheninperfectconditionand
inconsiderationoftheoperatinginstructions.
▶Forapplicationsplanningandoperationofthedevice,observe
theplant-specicsafetyregulations.
▶Only the media listed in chapter “Technicaldata”shouldbefed
into the medium ports.
▶Observethegeneralrulesoftechnicalequipment.
▶Theplantownerisresponsibleforthesafeoperationandhan-
dlingoftheplant.
english
Type 2933, 2934, 2935, 2973,
2974, 2975

7
General notes
4 GENERAL NOTES
4.1 Contact addresses
Germany
Bürkert Fluid Control Systems
Sales Centre
Christian-Bürkert-Str.13–17
D-74653Ingelngen
Tel.+49(0)7940-1091111
Fax+49(0)7940-1091448
E-mail:[email protected]
International
Thecontactaddressescanbefoundonthebackpagesofthe
printed operating instructions.
They are also available online at: country.burkert.com
4.2 Warranty
Apreconditionforthewarrantyisthatthediaphragmvalveisused
asintendedinconsiderationofthespeciedoperatingconditions.
4.3 Information on the Internet
Operatinginstructionsanddatasheetsfortype2933,2934,
2935,2973,2974,2975canbefoundonlineat:
country.burkert.com
5 PRODUCT DESCRIPTION
5.1 Structure and description
The device is a manually controlled diaphragm valve with diaphragm
seal.Thevalveconsistsofamanualactuatorandavalvebody.
5.2 Variants
Types293xand297xaredierentiatedbytheactuator.
Thexisdierenttothevalvebody.
5.2.1 Type 2933
Handwheel
Diaphragm
Valve body
Attachment with scale
Port connection
Fig. 1: Example of 2/2-way valve, type 2933
english
Type 2933, 2934, 2935, 2973,
2974, 2975

8
Product description
5.2.2 Type 2934 with T-valve body
Handwheel
Attachment with scale
Diaphragm
T-Valve body
Port connection
Fig. 2: Example of valve with T-valve body, type 2934
5.2.3 Type 2935 with tank bottom body
Handwheel
Attachment with scale
Diaphragm
Tank bottom body
Port connection
Fig. 3: Example of valve with tank bottom body, type 2935
5.2.4 Type 2973, 2974, 2975
Handwheel with lock
(optional)
Valve body
Diaphragm
Attachment with scale
Port connection
Fig. 4: Example of 2/2-way valve, type 2973
5.3 Function
Bymanuallyactivatingthehandwheel,theforceistransmittedviaa
spindle and the valve is opened or closed. The medium in the valve
bodyisreleasedorshuto.Turningthehandwheelanticlockwise
opens the valve, turning it clockwise closes the valve.
5.3.1 Position indicator actuator
5.3.1.1 Actuator DN8
When turning the handwheel anticlockwise, a yellow marking
becomes visible between the attachment and the handwheel.
english
Type 2933, 2934, 2935, 2973,
2974, 2975

9
Product description
Thevisibilityoftheyellowmarkingisnotdirectlyrelated
totheclosedpositionofthevalve.Dependingonthecon-
structionofthevalve,themarkingmay:
- not be visible when the valve is open, or
- visible when the valve is closed.
5.3.1.2 Actuator DN15 to DN50
Reproducible stroke scale
Handwheel with scale
Fig. 5: Position indicator
When turning the handwheel anticlockwise, a reproducible
stroke scale becomes visible between the attachment and the
handwheel.
Thevisibilityofthestrokescaleisnotdirectlyrelatedto
theclosedpositionofthevalve.Dependingonthecon-
structionofthevalve,thereproduciblestrokescalemay:
- not be visible when the valve is open, or
- visible when the valve is closed.
Thescaleon the handwheel determinesthe rotationposition of
thehandwheel(type293x:30positions,type297x:50positions).
Thereproduciblestrokescale showstherelativepositionofthe
valve and serves as a xed point for determining the rotational
position.
5.4 Product identication
5.4.1 Type label
Typ 2933 DN15 ER
00123456
S/N: 1001 W22MN
Tmed: -10...+145°C
NO01 NO17
D-74653
Ingelfingen
1
2
5
34
6
7
8
Fig. 6: Description of the type label (example)
Item Description Item Description
1Manufacturer 5 Medium temperature
2 Type 6 Valvebodysurface
roughness
3 Nominal diameter 7 Serial number
4 Seal material 8 Order number
english
Type 2933, 2934, 2935, 2973,
2974, 2975

10
Product description
5.4.2 Labelling on forged steel valve body
XXXXXXXXXX
XX F
1.4435/316L(VS)
PN16/CWP150
XXXXXXXX/XXX
XXXXXX
XXXX
1
2
3
4
5
6
7
8
Fig. 7: Labelling on forged steel valve body
Item Description Item Description
1 Company logo 5 Production number/
serial number
2 Material 6 Self-drainingangle
3 Nominal pressure
class(PN)
7Customer-specictext
(optional)
4 Batch number 8 Nominal diameter and
pipe dimensions
5.4.3 Labelling on cast valve body
5
6
23
4
1
Fig. 8: Labeling on cast valve body
Item Description Item Description
1 Company logo 4 Nominal diameter
(diaphragmsize)
2 Material 5 Batch number
3 Nominal pressure
class(PN)
6 Nominal diameter and
pipe dimensions
english
Type 2933, 2934, 2935, 2973,
2974, 2975

11
Technical data
5.4.4 Labelling on tube valve body
XXXXXXXXXX
PN16 / CWP150
XXXXXXXX / XXX
XXXX / XXXXXX
5
76
4
1.4435
316L(VP)
XXXXXXXX
23
1
Fig. 9: Labelling on tube valve body
Item Description Item Description
1 Company logo 5 Nominal diameter and
pipe dimensions
2 Material 6 Serial number
3 Heat 7 Self-drainingangle
4 Nominal pressure
class(PN)
6 TECHNICAL DATA
6.1 Standards and directives
The device complies with the valid EU harmonisation legislation.
Inaddition,thedevicealsocomplieswiththerequirementsofthe
lawsoftheUnitedKingdom.
Theharmonisedstandardsthathavebeenappliedfortheconformity
assessmentprocedurearelistedinthecurrentversionoftheEU
DeclarationofConformity/UKDeclarationofConformity.
UKCA marking with the importer address.
6.2 Mechanical data
Materials
Valve body type 2933,
2973
PVC, PP, PVDF
Precision-caststainlesssteel(VG),
Forgedsteel(VS),
Stainlesssteeltubevalvebody(VP)
Valve body type 2934,
2935, 2974, 2975
Stainless steel block material
Actuator PPS handwheel and attachment,
PPS handwheel and stainless steel
attachment
Diaphragm EPDM, PTFE/EPDM, advanced PTFE/
EPDM, GYLON®/EPDM laminated,
FKM
english
Type 2933, 2934, 2935, 2973,
2974, 2975

12
Technical data
6.3 Port connections valve body
Stainless steel valve body Welded connection
Clamp connection
Plastic valve body Spigot
True union
6.4 Operating conditions
Media Dirty, aggressive, ultra-pure, sterile
media with higher viscosity
6.4.1 Allowable temperatures
Ambienttemperaturefor
actuators
-10...+130 °C
(short-termupto+150°C)
Medium temperature for valve body
Stainless steel -10...+150 °C
PVC-U(see“Fig.10”) +10...+60 °C
PVDF(see“Fig.10”) -20....+120 °C
PP(see“Fig.10”) +10...+90 °C
Medium temperature for diaphragms
EPDM(AD) -10...+143 °C
Steamsterilisationupto+150°Cfor
60min
FKM(FF) 0...+130 °C
Nosteam/dryheatupto+150°Cfor
60min
PTFE(EA) -10...+130 °C
Steamsterilisationupto+140°Cfor
60min
Advanced PTFE
(EU)
-5...+143 °C
Steamsterilisationupto+150°Cfor
60min
Gylon®(ER) -5...+130 °C
Steamsterilisationupto+140°Cfor
60min
english
Type 2933, 2934, 2935, 2973,
2974, 2975

13
Technical data
6.4.2 Permitted medium pressure
Permittedmediumpressureforplasticvalvebodiesdependingon
medium temperature:
Temperature [°C]
PVC-U PP
PVDF
Medium pressure [bar]
Fig. 10: Pressure temperature diagram for plastic valve body as per
DIN EN ISO 16138
Theinformationisimportantforthematerialselection.
Observe the permitted operating pressure, depending on
the medium temperature.
Maximum permitted medium pressure
Thevaluesarevalidforvalvebodiesmadefrom:
• Plastic,
• Stainlesssteel:blockmaterial,forgedorcastedandtube
valve body.
Nominal
diameter
DN
(diaphragm
size)
Maximum permitted medium pressure
[bar]
EPDM/FKM PTFE/advanced
PTFE/Gylon®
8 10 10
15 10 10
20 10 10
25 10 10
32 10 10
40 10 10
50 7*/10 7*/10
Tab. 1: Maximum permitted medium pressure
* for handwheel and attachment made of PPS
english
Type 2933, 2934, 2935, 2973,
2974, 2975

14
Technical data
6.5 Flow values
6.5.1 Flow values for forged steel valve
bodies
Kv values [m3/h] for forged steel valve bodies VS
Diaph-
ragm
size
Nominal
diameter port
connection
(DN)
Seal
material
DIN ISO ASME BS SMS
8 6 EPDM 1.1
PTFE 1.1
8 / 1/4"EPDM 1.7 1.5 0.7 0.5
PTFE 1.9 2.0 0.7 0.5
10 / 3/8"EPDM 1.5 1.5 1.6 1.4
PTFE 1.9 2.0 1.8 1.6
15 / 1/2"EPDM 1.5
PTFE 1.9
15 10 / 3/8"EPDM 3.5 5.5
PTFE 3.4 5.2
15 / 1/2"EPDM 6.5 6.5 3.1 3.7
PTFE 6.0 6.0 3.1 3.6
20 / 3/4"EPDM 6.5
PTFE 6.0
20 20 / 3/4"EPDM 12.4 12.5 8.4 8.9
PTFE 12.0 12.0 8.5 8.8
25 25 / 1"EPDM 20.0 18.0 15.5 16.0
PTFE 17.0 16.0 14.5 14.8
40 32 EPDM 34.0
PTFE 34.0
40 / 1 1/2"EPDM 40.0 41.0 37.0 38.0
PTFE 40.0 40.0 37.5 38.0
50 50 / 2"EPDM 66.0 66.0 66.0 66.0
PTFE 66.0 67.0 66.0 66.0
2 1/2"EPDM 66.0
PTFE 66.0
Tab. 2: Kv values for forged steel valve bodies
english
Type 2933, 2934, 2935, 2973,
2974, 2975

15
Technical data
6.5.2 Flow values for cast valve bodies
Kv values [m3/h] for cast valve bodies VG
Diaphragm
size
Nominal
diameter port
connection
(DN)
Seal material Cast valve body
VG (all standards)
8 8 EPDM 0.95
PTFE 1.5
15 15 EPDM 5.6
PTFE 5.3
20 20 EPDM 10.7
PTFE 10.5
25 25 EPDM 14.6
PTFE 13.6
32 32 EPDM -
PTFE -
40 40 EPDM 35.0
PTFE 35.0
50 50 EPDM 47.0
PTFE 48.0
Tab. 3: Kv values for cast valve bodies
6.5.3 Flow values for tube valve bodies
Kv values [m3/h] for tube valve body VP (IHU2) TVB3G
Diaphragm
size
Nominal
diameter
port con-
nection (DN)
Seal
material
DIN ISO ASME
8 8 / 1/4"EPDM 1.9
PTFE 2.4
10 / 3/8"EPDM 1.9
PTFE 2.4
15 / 1/2"EPDM
PTFE 2.2
15 15 / 1/2"EPDM 7.2 7
PTFE 6.7 6.6
20 / 3/4"EPDM 6.9
PTFE 5.5 6.5
20 20 / 3/4"EPDM 13.5
PTFE 12.1
25 / 1"EPDM 14.9
PTFE 13.7 12.7
english
Type 2933, 2934, 2935, 2973,
2974, 2975

16
Installation
25 25 / 1"EPDM 17.3
PTFE 14.1
32 EPDM 18.6
PTFE 14.2
25 / 1"EPDM 19.1
PTFE 15.6
32 EPDM 20.0
PTFE 15.8
32 32 EPDM 36.0
PTFE 36.0
40 / 1 1/2"EPDM 35.0
PTFE 34.5 32.0
40 40 / 1 1/2"EPDM 48.0
PTFE 47.0
50 / 2"EPDM 46.0
PTFE 43.5 45.0
50 50 / 2"EPDM 70.0
PTFE 70.0
Tab. 4: Kv values for tube valve bodies
7 INSTALLATION
DANGER
Risk of injury due to high pressure and escaping medium.
▶Switchothepressurebeforeworkingonthedeviceorsystem.
Vent or empty the lines.
WARNING
Risk of injury due to improper installation.
▶Assembly may be carried out by authorised technicians only
and with the appropriate tools.
▶Observe tightening torques.
Risk of injury from unintentional activation of the system and
uncontrolled restart.
▶Secure the system against unintentional activation.
▶Following installation, ensure a controlled restart.
CAUTION
Risk of injury due to heavy device.
During transportation or installation work, a heavy device may
falldownandcauseinjuries.
▶Transport,installandremoveheavydevicewiththeaidofa
second person only.
▶Use suitable tools.
english
Type 2933, 2934, 2935, 2973,
2974, 2975

17
Installation
7.1 Information for the correct
installation position
Dependingonthevalvebody,theinstallationpositionofthedia-
phragmvalveisdierent.
Installation for leakage detection:
Oneofthereliefboresinthediaphragmsocketformoni-
toring leakages must be at the lowest position.
7.1.1 Installation position of 2/2-way valve
body
Installationposition:any,preferablyactuatorfacingup.
Ensuring self-draining:
Itistheresponsibilityoftheinstallerandtheoperatorto
ensureself-draining.
Self-drainingmustbeconsideredduringtheinstallation:
1.Angleofinclinationofthepipeline:
• Theangleofinclinationshouldcorrespondtotheangleof
inclinationofthepipeline.Forthepipeline,werecommendthe
inclination angles according to the valid ASME BPE.
2.Self-drainingangleforvalvebody:
• Theself-drainingangle(α)dependsonthevalvebodysize(dia-
phragmsize)andtheinnerdiameteroftheportconnection(DN).
• Theself-drainingangleisspeciedasavalueonforgedsteel
valvebodies(VS)andtubevalvebodies(VP)(see“Fig.7” and
“Fig.9”).
• Themarkingontheportconnectionofvalvebodiesservesas
an orientation aid. The marking must point upwards.
• Theactualself-draininganglemustbesetwithasuitable
measuring tool.
• Forvalvebodieswithoutangleinformation,youcanndthe
self-drainingangleontheInternet:
www.burkert.com
Type/Manuals/Supplementaryinformation
“Angleinformationforself-drainageofdiaphragmvalves”.
α
Inclinationangleofthepipeline
Markfor
self-draining
upwards
Fig. 11: Installation position for self-draining of the valve body
english
Type 2933, 2934, 2935, 2973,
2974, 2975

18
Installation
7.1.2 Installation position of T-valve body
Thefollowinginstallationpositionsarerecommendedfortheinstal-
lationoftheT-valveincircularpipelines:
Whenmediumisfed: When medium is removed:
Fig. 12: Installation position of type 2934/2974
7.2 Preparatory work
→Clearimpuritiesfrompipelines(sealmaterial,metalchips,etc.).
→Support and align pipelines.
Devices with bonded or adhesive bodies:
Theactuatoranddiaphragmmustbedismantledbefore
welding or bonding the valve body.
7.2.1 Welding tank bottom body
DANGER
Risk of injury due to high pressure and escaping medium.
▶Switchothepressurebeforeworkingonthedeviceorsystem.
Vent or empty the lines.
Recommendations
Observe the sequence:
1. Weld the tank bottom body to the container base
beforethecontainerisassembled. Itispossibletoweld
ontoaready-assembledcontainerbutitismoredicult.
Note:weldthetankbottombodyinthemiddleofthecon-
tainer base so that the container can be optimally drained.
2. Weld the tank bottom body into the pipeline.
→Ensure that pipelines are in alignment.
→Supportandalignpipelines.Toensurethatthepipelineisself-
draining, we recommend the inclination angles according to the
valid ASME BPE.
english
Type 2933, 2934, 2935, 2973,
2974, 2975

19
Installation
Forinformationoncontainersandinstructionsforwelding,
refertotheASMEVIIIDivisionIstandard.Checkthebatch
number indicated on the manufacturer’s certicate 3.1
suppliedbeforestartingweldingwork.
Observetheapplicablelawsofthecountrywithregardto
thequalicationofweldersandtheexecutionofwelding
work.
→Welding the tank bottom body to the container.
NOTE
Note when welding:
▶Onlyuseweldingmaterialsthataresuitableforthetankbot-
tom body.
▶The tank bottom valve must not collide with any other instal-
lation part. The actuator must be easy to install and remove.
→Weld the tank bottom body into the pipeline.
Ensure that there is no voltage present and minimal vibration
during installation.
→Installdiaphragmandactuatorafterwelding.
7.3 Install device
NOTE
The following must be heeded when installing the device in
the system:
▶Thedeviceandreliefboremustbeaccessibleforinspections
and maintenance work.
7.3.1 Device with welded connection or
bond connection
NOTE
To prevent damage.
▶Dismantle the actuator and diaphragm before welding or
bonding the valve body.
→Rotate the handwheel anticlockwise until it comes to a stop
(UPposition).
→Loosenthefasteningscrewscrosswiseandremovetheactuator
withdiaphragmfromthevalvebody.
→Weld or bond the valve body into the pipeline.
→After welding or bonding the valve body, smooth the body
surface(ifnecessary)bysanding.
→Cleanvalvebodycarefully.
→Place the actuator together with diaphragm on the valve body.
→Slightlytightenthefasteningscrewscrosswiseuntilthedia-
phragm rests between the valve body and the actuator.
→Close and open the diaphragm valve twice to ensure that the
diaphragm is properly seated.
→Closethediaphragmvalveagainandopenitapprox.20%.
english
Type 2933, 2934, 2935, 2973,
2974, 2975

20
Installation
NOTE
Damage to the device when failing to observe tightening torque.
▶Observe tightening torques.
→Tighteneachfasteningscrewin3stages(approx.1/3,approx.
2/3,3/3ofthetighteningtorqueinaccordancewith“Tab.5”)
crosswise. The diaphragm should be positioned and pressed
evenly around the actuator and valve body.
7.3.2 Tightening torques
Nominal diameter
DN
(diaphragm size)
Tightening torques [Nm]*
Diaphragm
EPDM/FKM
Diaphragm
PTFE/advanced
PTFE/Gylon®
8 2 2.5
15 3.5 4
20 4 4.5
25 5 6
32 6 8
40 8 10
50 12 15
Tab. 5: Tightening torques depending on diaphragm
* A tolerance of +10% of the respective tightening torque applies to all values
7.4 Set stroke limit
7.4.1 Set stroke limit, type 293x
Minimumstrokelimitisavailablefortype2933,2934and2935.
Ahexagonnutisusedforthispurpose.
→Turn the handwheel clockwise to move the valve to the closed
position.
→Loosen the screw on the handwheel (hexagon socket, width
acrossats2)andremovehandwheel.
Hexagon nut
Square
Screw on handwheel
Fig. 13: Set stroke limit type 293x
→Screwhexagonnutdownasfarasitwillgo.
Minimum stroke is set.
→Mount handwheel on actuator. The square on the spindle and
thehexagonofthenutmustbeincorrectalignmentwiththe
geometryinthehandwheelsothattheytintoeachother.
english
Type 2933, 2934, 2935, 2973,
2974, 2975