Festo VZXA-K, Instructions, Operation

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6 Product overview
6.1 Configuration
6.1.1 Product design
1 Position indicator
2 Pneumatic port (2)
3 Drive housing
4 Pipe connection; feed or forward-
ing (depending on flow direction)
5 Leakage hole
6 Arrow for flow direction
7 Valve housing
8 Drive interface / valve with span-
ner flat
9 Pneumatic 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 z 10 … +180 °C Temperature of medium
M3 z 30 … +200 °C
V13 Stainless steel 1.4409 Valve housing material
V14 Stainless steel ASTM A351-CF3M
TP PTFE modified Seat 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 G x 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 ["] ½ ¾ 1 1 ¼ 1 ½ 2
Max. pipe connection tight-
ening torque [Nm] 105 200 350 450 540 620
Tab. 6 Pipe connection tightening torque