Festo VZXA-K Operation and maintenance manual

Translation of the original instructions
1 About this document
This document describes the use of the above-mentioned product. It contains
additional information for use of the product in safety-related systems (safety
handbook in accordance with IEC61508).
1.1 Further applicable documents
All available documents for the product èwww.festo.com/pk.
1.2 Specified standards
Version
IEC61508:2010 Part 1,2,4…7 IEC61511:2016
Tab. 1 Standards specified in the document
2 Safety
2.1 General safety instructions
– Only use the product in original status without unauthorised modifications.
– Only use the product if it is in perfect technical condition.
– Use the valve only in the flow direction indicated.
– Take into consideration the ambient conditions at the location of use.
Media
– Only use media in accordance with the specifications è 16 Technical data.
– Use only media that will not cause dangerous reactions if mixed.
– Do not operate the product with chemically unstable gases, abrasive mediaor
solid materials.
– If water is used: up to approx.1000 ppm of chloride content is permitted.
Avoid tensile stresses.
– If aggressive media are used: limit temperature of medium to 65°C.
Actuator
– Do not open the actuator (pressure in the actuator or loaded spring).
– Avoid mechanical stresses on the valve. Do not use the actuator as a lever.
Return to Festo
Hazardous substances can endanger the health and safety of personnel and
cause damage to the environment. To prevent hazards, the product should only
be returned upon explicit request by Festo.
– Consult your regional Festo contact.
– Complete the declaration of contamination and attach it to the outside of the
packaging.
– Comply with all legal requirements for the handling of hazardous substances
and the transport of dangerous goods.
2.2 Intended use
The angle seat valve VZXA-...-K is intended to shut-off gaseous or liquid media in
piping systems.
– To control liquid media, use only the product variant VZXA-B-... Use (media
flow under valve seat).
2.3 Training of qualified personnel
Work on the product should only be conducted by qualified personnel. The quali-
fied personnel must be familiar with installation of process automation systems.
3 Information on functional safety
3.1 Operating conditions
– General information on safe operation è 2 Safety.
– Periodic tests (performance test) è 11 General.
– Ambient conditions and additional technical specifications
è 16 Technical data.
3.2 Achievable safety rating
The product is suitable for use as an element in a safety-related system in accord-
ance with IEC 61511.
– In low-demand mode up to SIL 2
– In high-demand mode up to SIL 2.
Taking into account the necessary minimum hardware fault tolerance of HFT = 1,
the product can also be used up to SIL 3 with a redundant execution of the entire
system.
NOTICE!
It is only possible to determine whether the product is suitable for specific applic-
ations by also assessing further components of the subsystem.
3.3 Safety function
Single-acting valves
The safety function comprises acceptance of the initial position on request. The
request is implemented by removal of the operating pressure.
– Valves with NO control function: the valve opens completely and remains
open until operating pressure is applied.
– Valves with NC control function: the valve closes completely and remains
closed until operating pressure is applied.
Double-acting valves
The safety function comprises acceptance of the required position on request.
This requires an external power supply.
3.4 Characteristic values
Safety standards (in accordance with IEC 61508) Value
Assessment path (Route of assessment) 2H / 1S
Type of subsystem (Type of Sub System) Type A
Operating mode (Mode of Operation) Low Demand and
High Demand
Test interval (Assumed Test Interval) Ti1 a
Confidence level (Confidence Level) 1-á 95 %
Hardware fault tolerance (Hardware Fault Tolerance) HFT 0
Failure rate for dangerous errors (Lambda Dangerous) ëD1.36 * 10-7/h
Failure rate for dangerous errors not detected (Lambda Dan-
gerous Undetected)
ëDU 1.36 * 10-7 /h
Mean time to dangerous failure (Mean Time To Dangerous Fail-
ure)
MTTFD7.37 * 106 h
Degree of coverage of dangerous errors through the proof test
(Proof Test Coverage)
PTC 95 %
Low Demand Mode
Assumed demands per year (Assumed Demands per Year) nop 1 / a
Mean probability of dangerous failure on demand (Average
Probability of Failure on Demand)
PFDavg 5.95 * 10-4
High Demand Mode
Assumed demands per year (Assumed Demands per Year) nop 1/h
(8760/a)
Mean frequency of a dangerous failure per hour (Probability of
dangerous Failure per Hour)
PFH 1.36 * 10-7/h
Tab. 2 Safety standards (in accordance with IEC 61508)
4 Further information
– Accessories èwww.festo.com/catalogue.
– Spare parts èwww.festo.com/spareparts.
5 Service
Contact your regional Festo contact person if you have technical questions
èwww.festo.com.
8119907
VZXA-K
Angle seat valve with piston actuator
8119907
2019-08b
[8119909]
Instructions| Operation
Festo AG & Co. KG
Ruiter Straße 82
73734 Esslingen
Germany
[phone]
www.festo.com

6 Product overview
6.1 Configuration
6.1.1 Product design
1Position indicator
2Pneumatic port (2)
3Drive housing
4Pipe connection; feed or forward-
ing (depending on flow direction)
5Leakage hole
6Arrow for flow direction
7Valve housing
8Drive interface / valve with span-
ner flat
9Pneumatic port (4)
Fig. 1 Product design
Position indicator
The pneumatic position indication shows the position of the actuator stem.
Indicator cylinder above Indicator cylinder below
Actuator stem retracted, valve opened Actuator stem extended, valve closed
Tab. 3 Position indicator
6.1.2 Product variants and type code
The following section explains selected product characteristics that are necessary
to understand the instruction manual. Description of the complete type code
èwww.festo.com/catalogue.
Feature Value Description
Type VZXA Angle seat valve
A above valve seat, closing in the direction of media flow
(for gaseous media)
Media flow
B under valve seat, closing against the direction of media
flow (for gaseous and liquid media)
Connection type TS6, TS7,
TS13
Line connection and connection standard
è 16.1 Technical data, general
M2 z10…+180 °C Temperature of medium
M3 z30…+200 °C
V13 Stainless steel 1.4409Valve housing material
V14 Stainless steel ASTM A351-CF3M
TP PTFE modifiedSeat seal material
T PTFE
Medium pressure 4 to 30 0…4 bar to 0…30 bar
(product versions suitable for vacuum application
è Tab. 14 Limit values of media pressure and
operating pressure VZXA-B-...-K-46,
è Tab. 15 Limit values of media pressure and
operating pressure VZXA-B-...-K-75)
Actuator K Piston drive
Actuator size 46, 75 46 mm, 75 mm
closed via spring force, NC
D double-acting
S opened by spring force, NO
Control function
PR closed by reduced spring force, NC
Tab. 4 Description of key features
6.2 Function
The angle seat valve VZXA-...-K is an externally controlled 2/2-directional control
valve with piston drive. The valve seat is slanted approx. 40° toward the media
flow. To close the valve, the valve actuator using the piston rod presses the valve
disc into the valve seat in a force fit.
The supply of the operating medium is controlled by an external valve (usually
electrically actuated) that must also be integrated into the supply cable for the
drive.
The actuator can be rotated 360° around the valve body.
Flow over valve seat
– The valve is closed by spring force with the medium flow.
– Media pressure assists the closing of the valve.
– The valve is opened by operating pressure.
– Only suitable for gaseous media, because use of incompressible media
causes pressure surges in the piping.
Flow under valve seat
The valve is closed by spring force or by operating pressure against the media
flow.
– Media pressure assists the opening of the valve.
– In some designs media pressure that is too high or operating pressure that is
too low can result in the valve not closing completely.
Control function
Single-acting Double-acting
Closed by spring force or by
reduced spring force (normally
closed - NC)
Opened by spring force (nor-
mally open- NO)
Opening and closing by two-
way pressurising with operating
medium (compressed air)
Tab. 5 Control function
7 Transport and storage
• For delivery of used products: Comply with all legal requirements for the
handling of hazardous substances and the transport of dangerous goods. For
returns to Festo è 2 Safety.
• Store the product in a cool, dry, UV-protected and corrosion-protected envir-
onment. Ensure that storage times are kept to a minimum.
8 Assembly and installation
With angle seat valves VZXA-...-K46-..., use only fittings Gx with max. SW14.
Requirements
– The piping is unpressurised, and no medium flows in it.
– The line ends are mounted.
– Connecting cables and fittings are clean.
Cleaning the valve
• Remove all transport packaging. The material used in the packaging has been
specifically chosen for its recyclability (exception: oil-impregnated paper =
residual waste).
Traces of residual grease may be evident on the product due to the production
process used.
• Clean the valve immediately before installation.
Installing the valve
WARNING!
Risk of injury due to slipping or falling objects.
The valve can weigh up to 5.75 kg, depending on the product version. Body parts
can be crushed. This could cause serious head injury in overhead installations.
• Secure the valve from falling or slipping with suitable equipment.
1. Bring the valve into its mounting position.
– Observe the flow direction. The permitted flow direction is marked by an
arrow on the valve housing è Fig.1, 6.
2. Connect the piping to the valve housing.
– Tightening torque è Tab. 6 Pipe connection tightening torque
3. Connect the operating medium line.
– Pneumatic connection (2): operating medium
– Pneumatic connection (4): exhaust port for single-acting drives or operat-
ing medium for double-acting drives
4. For single-acting drives: mount the silencer in the exhaust port or use a
tubing connection for guided exhaust air.
Connection size ["] ½¾1 1¼1½2
Max. pipe connection tight-
ening torque
[Nm] 105 200 350 450 540 620
Tab. 6 Pipe connection tightening torque

9 Commissioning
WARNING!
Risk of injury from manipulation in the operating area of the angle seat valve.
Limbs can be cut or severed.
• Operate the angle seat valve only if it is fully mounted.
Requirements
– The valve is fully mounted and connected.
Checking operating conditions
1. Check operating conditions and limit values è 16 Technical data.
2. Check connection points for tightness.
3. Check compatibility of the devices in the system for maximum pressure (con-
sider pressure peaks). If necessary, adjust the application parameters.
Commissioning the valve with single-acting drives
1. Supply medium.
2. Slowly apply operating pressure to the valve. The operating pressure required
for reliable switching of the valve depends on the medium pressure
è 16.2 Technical data, pneumatic.
3. Function and direction control of the individual pneumatic drives.
Commissioning the valve with double-acting drives
1. Slowly apply operating pressure to the valve. The operating pressure required
for reliable switching of the valve depends on the medium pressure
è 16.2 Technical data, pneumatic.
2. Supply medium.
3. Function and direction control of the individual pneumatic drives.
10 Operation
WARNING!
Risk of injury from touching hot surfaces.
Valve housing and actuator can become hot at high temperature of medium.
Severe burns are possible.
• Do not touch the angle seat valve during operation or immediately afterward.
• Comply with operating conditions.
• Comply with maintenance conditions è 11 General.
After longer idle times:
• Actuate the valve several times and check for correct function.
11 General
WARNING!
Risk of injury from touching hot surfaces.
Valve housing and actuator can become hot at high temperature of medium.
Severe burns are possible.
• Allow the angle seat valve to cool off before working on it.
• Check product regularly from the outside for leakage and function.
• Check function of the product regularly.
• Clean product regularly with commercial cleaning agents.
11.1 Proof test Proof Test)
The proof test (Proof Test) consists of shutting the operating pressure off and on.
• Run the proof test once a year.
During the proof test, the safety of the application must be ensured.
1. Shut off operating pressure.
2. Check valve position.
ÄThe test is successful if the safe state is reached within the specified
time. For assessment of the safe state è 3.3 Safety function.
3. Slowly apply operating pressure to the valve.
ÄThe test will be successful if the valve returns to its original position.
4. Check the valve externally (visual inspection).
ÄThe test is successful if no defect or leakage is detected.
5. Document test results.
12 Malfunctions
Fault description Cause Remedy
VZXA-B: media pressure is too
high or operating pressure too
low.
Set required differential pres-
sure or adjust operating pres-
sure è 16 Technical data.
Valve does not close or closes
too slowly.
Medium contains too many or
too large contaminants.
Comply with operating condi-
tions.
VZXA-A: operating pressure is
too low or media pressure is
too high.
Adjust operating pressure or
media pressure.
Valve does not open or opens
too slowly.
VZXA-B: operating pressure is
too low.
Adjust operating pressure.
Medium leaks out of leakage
hole.
Seal cartridge is defective. Replace seal cartridge èSpare
parts documentation.
Fault description Cause Remedy
Medium cannot be shut off. Seat seal is defective. Replace seat seal èSpare
parts documentation.
Tab. 7
13 Modification
DANGER!
Risk of injury from flying objects.
Unsecured parts under pressure can fly around and injure people.
• Before replacing wearing parts, depressurise the valve and piping.
1Spanner flat for counter holding
2Interface screw SW46
Fig. 2 Demounting actuator
13.1 Removing actuator from the valve housing – in installed position
The actuator can be removed from the valve housing without having to remove
the valve from the piping.
1. Depressurise the piping and allow valve to cool to room temperature.
2. Secure the actuator with suitable equipment to prevent it from falling or slip-
ping.
3. Extend the actuator stem.
– With double-acting valves: pressurise port (4) (3bar).
– With valves with NO control function: pressurise connection (2) (3bar).
– For valves with NC control function: exhaust the actuator.
4. Loosen interface screw 2.
5. Remove actuator from the valve housing.
6. Shut off operating pressure.
13.2 Removing actuator from the valve housing – in removed position
1. Extend the actuator stem.
– With double-acting valves: pressurise port (4) (3bar).
– With valves with NO control function: pressurise connection (2) (3bar).
– For valves with NC control function: exhaust the actuator.
2. Loosen interface screw 2.
3. Remove actuator from the valve housing.
4. Shut off operating pressure.
13.3 Mounting actuator on the valve housing
1. Extend the actuator stem.
– With double-acting valves: pressurise connection (4) slowly (3bar).
– For valves with NO control function: pressurise connection (2) slowly
(3bar).
– For valves with NC control function: exhaust the actuator.
2. Push valve body spindle completely into the valve body.
3. Place actuator on valve housing.
4. Tighten interface screw 2.
– Tightening torque: 50 Nm
5. Shut off operating pressure.
13.4 Turning actuator
1. Loosen interface screw 2 (max. ½ turn).
2. Rotate actuator to desired position.
3. Tighten interface screw 2.
– Tightening torque: 50Nm

14 Disassembly
DANGER!
Risk of injury due to movement of pressurised parts.
The valve can switch if there is a drop in pressure. Limbs can be cut or severed.
• Before removal, move the valve to the closed position.
• Before removal, depressurise the valve and the piping.
WARNING!
Risk of injury from touching hot surfaces.
Valve housing and actuator can become hot at high temperature of medium.
Severe burns are possible.
• Allow the angle seat valve to cool off before working on it.
WARNING!
Risk of injury due to slipping or falling objects.
The angle seat valve can weigh up to 5.75kg, depending on the product version.
Body parts can be crushed.
• Secure angle seat valve against falling or slipping using appropriate means of
securing.
1. Depressurise the piping and the connecting cable of the operating medium.
Allow the valve and piping to cool.
2. Empty the piping and valve completely.
– Make sure no one is located in front of the outlet opening.
– Catch draining media in a suitable container.
3. Disconnect the connecting cable of the operating medium from the valve.
4. Disconnect the piping connections and remove the valve.
15 Disposal
– Dispose of the product in an environmentally friendly manner. In doing so,
take the remaining media into account (use of problematic materials if applic-
able)
– Observe the local regulations for environmentally friendly disposal.
16 Technical data
16.1 Technical data, general
Type VZXA-...-K
Constructive design Poppet valve with piston drive
Actuation type Pneumatic
Sealing principle Soft
Mounting position Any
Type of mounting In-line installation
Valve function 2/2
Flow direction Non-reversible
Product weight èwww.festo.com/catalogue
CE marking in accordance with declaration of conformity
èwww.festo.com/sp
Medium
Medium VZXA-A-... Compressed air grade of filtration 200ìm, inert gases,
vapour1)
Medium VZXA-B-... Compressed air grade of filtration 200ìm, inert gases,
water, neutral liquid media, petroleum, petroleum
based hydraulic fluid, vapour
Medium pressure [bar] –0.9…30, in accordance with information on product
labelling
Viscosity [mm2/s] £ 600
Operating medium
Operating medium Compressed air to ISO8573-1:2010 [7:4:4]
Operating pressure [bar] max. 10 è 16.2 Technical data, pneumatic
Ambient conditions
Temperature of medium
(modified PTFE seat seal
material)
[°C] –30…+200
Temperature of medium
(PTFE seat seal material)
[°C] –10…+180
Permissible min./max. tem-
perature (TS) (modified PTFE
seat seal material)
[°C] –30…+200
Permissible min./max. tem-
perature (TS) (PTFE seat seal
material)
[°C] –10…+180
Ambient temperature [°C] 0…+60
Actuator degree of protection IP65, IP67, IP67K (with guided exhaust air)
Valve housing connection
VZXA-...-TS6 Threaded collar in accordance with DIN ISO 228
VZXA-...-TS7 Threaded collar in accordance with ANSI/ASME B 1.20.1
VZXA-...-TS13 Threaded collar in accordance with DIN ISO 10226
Operating medium port GÁ
Type VZXA-...-K
Note on materials
Valve housing VZXA-...-V13 Stainless steel casting (1.4409)
Valve housing VZXA-...-V14 Stainless steel casting (ASTM A351-CF3M)
Seat seal VZXA-...-TP PTFE modified
Seat seal VZXA-...-T PTFE
Drive housing Stainless steel casting (1.4408)
Piston drive seals FPM
Actuator stem High-alloy stainless steel
Actuator cover Stainless steel casting (1.4408)
1) other media on request
Tab. 8 Technical data, general, VZXA
16.2 Technical data, pneumatic
Nominal pressure, burst pressure and flow rate of valve body VZXA-...-TS
Connection size ["] ½ ¾ 1 1¼1½2
Nominal width DN 13 20 25 32 40 50
Nominal pressure of fitting
PN
(up to 200°C temperature of
medium)
[bar] 40 25
Burst pressure
(up to 200°C temperature of
medium)
[bar] 200 125
Flow rate Kv1)
VZXA-B-...-46 [m3/h 6.0 13.3 20.3 27.9 -
VZXA-A-...-46 [m3/h 6.6 13.3 20.0 29.8 -
VZXA-B-...-75 [m3/h 5.9 13.5 22.6 30.3 41.4 50.1
VZXA-A-...-75 [m3/h 6.6 14.5 21.5 33.0 44.9 54.6
1) water, at +20°C, media pressure 1bar at valve inlet, free discharge
Tab. 9 Technical data, pneumatic, VZXA- -TS
Media pressure and operating pressure VZKA-B-...-K-46-...-S (media flow under
valve seat, NO)
Nominal width
DN
13 20 25
Max. media pressure [bar] 16 13.5 8.3
Min. operating pres-
sure
[bar] 3.4 5
Tab. 10 Limit values of media pressure and operating pressure VZKA-B-...-
M-46-...-S
DN13
DN20
DN25
p1 Medium pressure p2 Operating pressure
Fig. 3 Media pressure and operating pressure VZKA-B-...-K-46-...-S

Media pressure and operating pressure VZXA-B-...-K-75-...-S (media flow under
valve seat, NO)
Nominal width
DN
20 25 32 40 50
Max. media pressure [bar] 16 10 6.2
Min. operating pres-
sure
[bar] 3.4 4 5
Tab. 11 Limit values of media pressure and operating pressure VZXA-B-...-K-75-...-
S
DN20 DN25
DN32 DN40
DN50
p1 Medium pressure p2 Operating pressure
Fig. 4 Media pressure and operating pressure VZXA-B-...-K-75-...-S
Media pressure and operating pressure VZKA-B-...-K-46-...-D (media flow under
valve seat, double-acting)
Nominal width
DN
13 20 25 32
Max. media pressure [bar] 16 6
Min. operating pres-
sure
[bar] 2.8 3.1 4.8 5
Tab. 12 Limit values of media pressure and operating pressure VZKA-B-...-K-46-...-
D
DN13 DN20
DN25
DN32
p1 Medium pressure p2 Operating pressure
Fig. 5 Media pressure and operating pressure VZKA-B-...-K-46-...-D
Media pressure and operating pressure VZXA-B-...-75-...-D (media flow under
valve seat, double-acting)
Nominal width
DN
20 25 32 40 50
Max. media pressure [bar] 16 10
Min. operating pres-
sure
[bar] 2.8 3.8 5
Tab. 13 Limit values of media pressure and operating pressure VZXA-B-...-75-...-D
DN20 DN25 DN32
DN40
DN50
p1 Medium pressure p2 Operating pressure
Fig. 6 Media pressure and operating pressure VZXA-B-...-75-...-D
Media pressure and operating pressure VZXA-B-...-K-46 (media flow under valve
seat, NC)
Nominal width
DN
13 20 25 32
Medium pressure [bar] –0.9…30 –0.9…12.8 –0.9…8.3 –0.9…4.4
Min. operating pres-
sure
[bar] 4.8
Tab. 14 Limit values of media pressure and operating pressure VZXA-B-...-K-46
Media pressure and operating pressure VZXA-B-...-K-75 (media flow under valve
seat, NC)
Nominal width
DN
20 25 32 40 50
Medium pressure [bar] 0…30 0…23 0…13.5 –0.9…9.3 –0.9…5.6
Min. operating pres-
sure
[bar] 4.6
Tab. 15 Limit values of media pressure and operating pressure VZXA-B-...-K-75
Media pressure and operating pressure VZXA-B-...-K-46-...-PR (media flow
under valve seat, NC with reduced spring force)
Nominal width
DN
13 20
Max. media pressure [bar] 11.5 6
Min. operating pres-
sure
[bar] 2.6
Tab. 16 Limit values of media pressure and operating pressure VZXA-B-...-K-46-...-
PR
Media pressure and operating pressure VZXA-B-...-K-75-...-PR (media flow
under valve seat, NC with reduced spring force)
Nominal width
DN
20 25 32 40
Max. media pressure [bar] 16 9.3 4.8 4
Min. operating pres-
sure
[bar] 2.2
Tab. 17 Limit values of media pressure and operating pressure VZXA-B-...-K-75-...-
PR

Media pressure and operating pressure VZXA-A-...-K-46-...-PR (media flow
under valve seat, NC with reduced spring force)
Nominal width
DN
13 20 25 32
Max. media pressure [bar] 16 10 6.8
Min. operating pres-
sure
[bar] 2.6 4.1 5
Tab. 18 Limit values of media pressure and operating pressure VZXA-A-...-K-46-...-
PR
DN13
DN20
DN25
DN32
p1 Medium pressure p2 Operating pressure
Fig. 7 Media pressure and operating pressure VZXA-A-...-K-46-...-PR
Media pressure and operating pressure VZXA-A-...-K-75-...-PR (media flow
under valve seat, NC with reduced spring force)
Nominal width
DN
20 25 32 40 50
Max. media pressure [bar] 16 15.5 8
Min. operating pres-
sure
[bar] 2.4 3.1 4.2 5
Tab. 19 Limit values of media pressure and operating pressure VZXA-A-...-K-75-...-
PR
DN20 DN25
DN32 DN40
DN50
p1 Medium pressure p2 Operating pressure
Fig. 8 Media pressure and operating pressure VZXA-A-...-K-75-...-PR