Festo AG & Co. KG
Ruiter Straße 82
73734 Esslingen
Germany
+49 711 347-0
www.festo.com
Instructions| Operation
8119907
2019-08b
[8119909]
8119907
Translation of the original instructions
1About 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 IEC61508).
1.1Further applicable documents
All available documents for the product èwww.festo.com/pk.
1.2Specified standards
Version
IEC61508:2010 Part 1,2,4…7IEC61511:2016
Tab. 1 Standards specified in the document
2Safety
2.1General 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.
2.2Intended 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).
2.3Training of qualified personnel
Work on the product should only be conducted by qualified personnel. The qualified personnel must be familiar with installation of process automation systems.
3.2Achievable safety rating
The product is suitable for use as an element in a safety-related system in accordance 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 applications by also assessing further components of the subsystem.
3.3Safety 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.
3.4Characteristic values
Safety standards (in accordance with IEC 61508)Value
Failure rate for dangerous errors (Lambda Dangerous)ë
Failure rate for dangerous errors not detected (Lambda Dangerous Undetected)
Mean time to dangerous failure (Mean Time To Dangerous Failure)
Degree of coverage of dangerous errors through the proof test
(Proof Test Coverage)
Low Demand Mode
Assumed demands per year (Assumed Demands per Year)n
Mean probability of dangerous failure on demand (Average
Probability of Failure on Demand)
High Demand Mode
Assumed demands per year (Assumed Demands per Year)n
Mean frequency of a dangerous failure per hour (Probability of
dangerous Failure per Hour)
i
D
ë
DU
MTTF
PTC95 %
op
PFD
avg
op
PFH1.36 * 10-7/h
D
High Demand
1 a
1.36 * 10-7/h
1.36 * 10-7 /h
7.37 * 106 h
1 / a
-4
5.95 * 10
1/h
(8760/a)
Tab. 2 Safety standards (in accordance with IEC 61508)
4Further information
–Accessories èwww.festo.com/catalogue.
–Spare parts èwww.festo.com/spareparts.
5Service
Contact your regional Festo contact person if you have technical questions
èwww.festo.com.
3Information on functional safety
3.1Operating 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.
6Product overview
6.1Configuration
6.1.1Product design
Position indicator
1
Pneumatic port (2)
2
Drive housing
3
Pipe connection; feed or forward-
4
ing (depending on flow direction)
Leakage hole
5
Arrow for flow direction
6
Valve housing
7
Drive interface / valve with span-
8
ner flat
Pneumatic port (4)
9
Fig. 1 Product design
Position indicator
The pneumatic position indication shows the position of the actuator stem.
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.
The following section explains selected product characteristics that are necessary
to understand the instruction manual. Description of the complete type code
èwww.festo.com/catalogue.
FeatureValueDescription
TypeVZXAAngle seat valve
Media flow
Connection typeTS6, TS7,
Medium pressure4 to 300…4 bar to 0…30 bar
ActuatorKPiston drive
Actuator size46, 7546 mm, 75 mm
Control function
Aabove valve seat, closing in the direction of media flow
Bunder valve seat, closing against the direction of media
TS13
M2z10…+180 °C Temperature of medium
M3z30…+200 °C
V13Stainless steel 1.4409Valve housing material
V14Stainless steel ASTM A351-CF3M
TPPTFE modifiedSeat seal material
TPTFE
Ddouble-acting
Sopened by spring force, NO
PRclosed by reduced spring force, NC
(for gaseous media)
flow (for gaseous and liquid media)
Line connection and connection standard
è 16.1 Technical data, general
(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)
closed via spring force, NC
Tab. 4 Description of key features
6.2Function
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.
Closed by spring force or by
reduced spring force (normally
closed - NC)
Opened by spring force (normally open- NO)
Opening and closing by twoway pressurising with operating
medium (compressed air)
Tab. 5 Control function
7Transport 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 environment. Ensure that storage times are kept to a minimum.
8Assembly 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["]
Max. pipe connection tightening torque
[Nm]105200350450540620
½¾
11¼1½2
Tab. 6 Pipe connection tightening torque
9Commissioning
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 (consider 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.
10Operation
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.
11General
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.
11.1Proof 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.
The test is successful if the safe state is reached within the specified
Ä
time. For assessment of the safe state è 3.3 Safety function.
3. Slowly apply operating pressure to the valve.
The test will be successful if the valve returns to its original position.
Ä
4. Check the valve externally (visual inspection).
The test is successful if no defect or leakage is detected.
Ä
5. Document test results.
Fault descriptionCauseRemedy
Medium cannot be shut off.Seat seal is defective.Replace seat seal èSpare
parts documentation.
Tab. 7
13Modification
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.
Spanner flat for counter holding
1
Interface screw SW46
2
Fig. 2 Demounting actuator
13.1Removing 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 slipping.
3. Extend the actuator stem.
–With double-acting valves: pressurise port (4) (3bar).
–With valves with NO control function: pressurise connection (2) (3bar).
–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.
13.2Removing actuator from the valve housing – in removed position
1. Extend the actuator stem.
–With double-acting valves: pressurise port (4) (3bar).
–With valves with NO control function: pressurise connection (2) (3bar).
–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.
13.3Mounting actuator on the valve housing
1. Extend the actuator stem.
–With double-acting valves: pressurise connection (4) slowly (3bar).
–For valves with NO control function: pressurise connection (2) slowly
(3bar).
–For valves with NC control function: exhaust the actuator.
2. Push valve body spindle completely into the valve body.