SMC Networks VOA325 Series User manual

Doc. no.VT325∗∗-OMF0002-B
PRODUCT NAME
3 Port Air Operated Valve
MODEL / Series / Product Number
VTA/VOA325 Series

Contents
Safety Instructions --------------------------------------------------------------------------------- 2,3
Design/Selection ----------------------------------------------------------------------------------- 4
Mounting --------------------------------------------------------------------------------------------- 4
Piping ------------------------------------------------------------------------------------------------- 4,5
Lubrication ------------------------------------------------------------------------------------------- 5
Air Supply -------------------------------------------------------------------------------------------- 5
Operating Environment --------------------------------------------------------------------------- 5,6
Maintenance ---------------------------------------------------------------------------------------- 6
Specific Product Precautions -------------------------------------------------------------------- 7
Troubleshooting ------------------------------------------------------------------------------------ 8
- 1 - No.VT325∗∗-OMF0002-B

Safety Instructions
These safety instructions are intended to prevent hazardous situations and/or equipment damage.
These instructions indicate the level of potential hazard with the labels of “Caution,” “Warning” or “Danger.”
They are all important notes for safety and must be followed in addition to International Standards
(ISO/IEC)*1) , and other safety regulations.
*1) ISO 4414: Pneumatic fluid power -- General rules relating to systems.
ISO 4413: Hydraulic fluid power -- General rules relating to systems.
IEC 60204-1: Safety of machinery -- Electrical equipment of machines .(Part 1: General requirements)
ISO 10218: Manipulating industrial robots -Safety.
etc.
Caution
Caution indicates a hazard with a low level of risk which, if not avoided, could result
in minor or moderate injury.
Warning
Warning
indicates a hazard with a medium level of risk which, if not avoided, could
result in death or serious injury.
Danger
Danger
indicates a hazard with a high level of risk which, if not avoided, will result
in death or serious injury.
Warning
1. The compatibility of the product is the responsibility of the person who designs the equipment or
decides its specifications.
Since the product specified here is used under various operating conditions, its compatibility with specific
equipment must be decided by the person who designs the equipment or decides its specifications based on
necessary analysis and test results.
The expected performance and safety assurance of the equipment will be the responsibility of the person who
has determined its compatibility with the product.
This person should also continuously review all specifications of the product referring to its latest catalog
information, with a view to giving due consideration to any possibility of equipment failure when configuring the
equipment.
2. Only personnel with appropriate training should operate machinery and equipment.
The product specified here may become unsafe if handled incorrectly.
The assembly, operation and maintenance of machines or equipment including our products must be
performed by an operator who is appropriately trained and experienced.
3. Do not service or attempt to remove product and machinery/equipment until safety is confirmed.
1.The inspection and maintenance of machinery/equipment should only be performed after measures to
prevent falling or runaway of the driven objects have been confirmed.
2.When the product is to be removed, confirm that the safety measures as mentioned above are implemented
and the power from any appropriate source is cut, and read and understand the specific product precautions
of all relevant products carefully.
3. Before machinery/equipment is restarted, take measures to prevent unexpected operation and malfunction.
4. Contact SMC beforehand and take special consideration of safety measures if the product is to
be used in any of the following conditions.
1. Conditions and environments outside of the given specifications, or use outdoors or in a place exposed to
direct sunlight.
2. Installation on equipment in conjunction with atomic energy, railways, air navigation, space, shipping,
vehicles, military, medical treatment, combustion and recreation, or equipment in contact with food and
beverages, emergency stop circuits, clutch and brake circuits in press applications, safety equipment or
other applications unsuitable for the standard specifications described in the product catalog.
3. An application which could have negative effects on people, property, or animals requiring special safety
analysis.
4.Use in an interlock circuit, which requires the provision of double interlock for possible failure by using a
mechanical protective function, and periodical checks to confirm proper operation.
- 2 - No.VT325∗∗-OMF0002-B

Safety Instructions
Caution
1. The product is provided for use in manufacturing industries.
The product herein described is basically provided for peaceful use in manufacturing industries.
If considering using the product in other industries, consult SMC
beforehand and exchange
specifications or a contract if necessary.
If anything is unclear, contact your nearest sales branch.
Limited warranty and Disclaimer/Compliance Requirements
The product used is subject to the following “Limited warranty and Disclaimer” and “Compliance
Requirements”.
Read and accept them before using the product.
Limited warranty and Disclaimer
1.The warranty period of the product is 1 year in service or 1.5 years after the product is
delivered,whichever is first.
∗
2)
Also, the product may have specified durability, running distance or replacement parts. Please
consult your nearest sales branch.
2. For any failure or damage reported within the warranty period which is clearly our responsibility,
a replacement product or necessary parts will be provided.
This limited warranty applies only to our product independently, and not to any other damage
incurred due to the failure of the product.
3. Prior to using SMC products, please read and understand the warranty terms and disclaimers
noted in the specified catalog for the particular products.
∗
2) Vacuum pads are excluded from this 1 year warranty.
A vacuum pad is a consumable part, so it is warranted for a year after it is delivered.
Also, even within the warranty period, the wear of a product due to the use of the vacuum
pad or failure due to the deterioration of rubber material are not covered by the limited
warranty.
Compliance Requirements
1.
The use of SMC products with production equipment for the manufacture of weapons of mass
destruction(WMD) or any other weapon is strictly prohibited.
2. The exports of SMC products or technology from one country to another are governed by the
relevant
security laws and regulation of the countries involved in the transaction. Prior to the
shipment of a SMC product to another country, assure that all local rules governing that export
are known and f
ollowed.
Caution
SMC products are not intended for use as instruments for legal metrology.
Measurement instruments that SMC manufactures or sells have not been qualified by type approval tests
relevant to the metrology (measurement) laws of each country.
Therefore, SMC products cannot be used for business or certification ordained
by the metrology
(measurement) laws of each country.
- 3 - No.VT325∗∗-OMF0002-B

VTA/VOA325 Series
3 Port Air Operated Valve
Precautions 1
Be sure to read this before handling products.
Design/Selection
1. Confirm the specifications.
This product is designed only for use in compressed air
systems. Do not operate at pressures, temperatures, etc.,
beyond the range of specifications, as this can cause damage
or malfunction.
Please contact SMC when using a fluid other than
compressed air.
We do not guarantee against any damage if the product is
used outside of the specification range.
2. Actuator drive
When an actuator, such as a cylinder, is to be driven using a
valve, take appropriate measures (such as the installation of a
cover or the restricting of access to the product) to prevent
potential danger caused by actuator operation.
3. Intermediate stops
Due to the compressibility of air, it is difficult for this product to
make a piston stop at the required intermediate position
accurately and precisely.
Furthermore, since valves and cylinders are not guaranteed
for zero air leakage, it may not be possible to hold a stopped
position for an extended period of time.
Please contact SMC if it is necessary to hold a stopped
position for an extended period of time.
4. Effects of back pressure when using a
manifold
Use caution when valves are used on a manifold because
actuators may malfunction due to back pressure.
When a single acting cylinder is operated, take appropriate
rmeasures to prevent malfunction by using an individual EXH
manifold.
5. Holding pressure
Since valves are subject to air leakage, they cannot be used
for applications such as holding pressure in a pressure vessel.
6. Not suitable for use as an emergency shutoff
valve, etc.
The valves presented in this catalog are not designed for
safety applications (e.g. emergency shutoff valve). If the valves
are used in such applications, additional safety measures
should be adopted.
7. Release of residual pressure
For maintenance and inspection purposes install a system for
releasing residual pressure.
8. Ventilation
Provide ventilation when using a valve in a confined area,
such as in a closed control panel. For example, install a
ventilation opening, etc., in order to prevent pressure from
increasing inside of the confined area and to release the heat
generated by the valve.
9. Do not disassemble the product or make any
modifications, including additional machining.
Doing so may cause human injury and/or an accident.
1. Operation in low temperature conditions
It is possible to operate the valve in extreme temperatures, as
low as 5oC. Take appropriate measures to avoid the freezing
of drainage, moisture, etc. in low temperatures.
2. Mounting orientation
Mounting orientation is not specified.
3. Initial lubrication of main valve
Grease has been applied to the main valve as initial lubricant.
Mounting
1. Operation manual
Install the products and operate them only after reading the
operation manual carefully and understanding its contents.
Also, keep the manual where it can be referred to as
necessary.
2. Ensure sufficient space for maintenance
activities.
When installing the products, allow access for maintenance
and inspection.
3. Tighten threads with the proper tightening
torque.
When installing the products, follow the listed torque
specifications.
4. If air leakage increases or equipment does not
operate properly, stop operation.
Check mounting conditions when air and power supplies are
connected. Initial function and leakage tests should be
performed after installation.
5. Painting and coating
Warnings or specifications printed on or affixed to the product
should not be erased, removed, or covered up.
Please consult with SMC before applying paint to resinous
parts, as this may have an adverse effect due to the solvent in
the paint.
Piping
1. Preparation before piping
Before piping is connected, it should be thoroughly blown out
with air (flushing) or washed to remove chips, cutting oil, and
other debris from inside the pipe.
2. Winding of sealant tape
When screwing piping or fittings
into ports, ensure that chips
from the pipe threads or sealing
material do not enter the piping.
Also, if sealant tape is used,
leave 1 thread ridge exposed at
the end of the threads.
- 4 -No.VT325∗∗-OMF0002-B

VTA/VOA325 Series
3 Port Air Operated Valve
Precautions 2
Be sure to read this before handling products.
Piping
3. Connection of fittings
For a fitting with sealant R or NPT, first, tighten it by hand,
then use a suitable wrench for the hexagon flats of the
body to tighten it a further two or three turns.
For the tightening torque, refer to the table below.
Connection thread size
(R, NPT)
Proper tightening torque
(N·m)
1/4
8 to 12
3/8
15 to 20
4. Piping to products
When piping to a product, refer to the drawing to avoid
mistakes regarding the supply port, etc.
Note) Pilot port size of this product is 1/8.
This product is universal porting type. N.C type, N.O. type,
divider type and selector type can be used.
Lubrication
1. Lubrication
The valve has been lubricated for life by the factory and does
not require any further lubrication.
If a lubricant is used in the system, use class 1 turbine oil (no
additives), ISO VG32.
Once lubricant is utilized within the system, since the original
lubricant applied within the product during manufacturing will
be washed away, please continue to supply lubrication to the
system. Without continued lubrication, malfunctions could
occur.
If turbine oil is used, refer to the Safety Data Sheet (SDS) of
the oil.
2. Lubrication amount
If too much oil is applied, it may accumulate inside the valve,
causing malfunction or response delay. So, do not apply a
large amount of oil.
Air Supply
1. Type of fluids
Please consult with SMC when using the product in
applications other than compressed air.
2. When there is a large amount of drainage
Compressed air containing a large amount of drainage can
cause the malfunction of pneumatic equipment. An air dryer or
water separator should be installed upstream from filters.
3. Drain flushing
If condensation in the drain bowl is not emptied on a regular
basis, the bowl will overflow. This may cause the malfunction
of pneumatic equipment. If the drain bowl is difficult to check
and remove, the installation of a drain bowl with an auto drain
option is recommended.
For compressed air quality, refer to the SMC Best Pneumatics
catalog No. 6.
4. Use clean air
Do not use compressed air that contains chemicals, synthetic
oils that include organic solvents, salt, corrosive gases, etc.,
as it can cause damage or malfunction.
1. When extremely dry air is used as the fluid,
degradation of the lubrication properties
inside the equipment may occur, resulting in
reduced reliability (or reduced service life) of
the equipment. Please consult with SMC.
2. Install an air filter.
Install an air filter upstream near the valve. Select an air filter
with a filtration size of 5 μm or smaller.
3. Take measures to ensure air quality, such as
by installing an aftercooler, air dryer, or water
separator.
Compressed air that contains a large amount of drainage can
cause the malfunction of pneumatic equipment, such as
valves. Therefore, take appropriate measures to ensure air
quality, such as by providing an aftercooler, air dryer, or water
separator.
4. If an excessive amount of carbon powder is
present, install a mist separator on the
upstream side of the valve.
If excessive carbon dust is generated by the compressor, it
may adhere to the inside of a valve and cause it to
malfunction.
For compressed air quality, refer to the SMC Best Pneumatics
catalog No. 6.
Operating Environment
1. Do not use in an atmosphere containing
corrosive gases, chemicals, sea water, water,
water steam, or where there is direct contact
with any of these.
2. Do not use in an environment where
flammable gas or explosive gas exists. Usage
may cause a fire or explosion. The products
do not have an explosion proof construction.
3. Do not use in a place subject to heavy
vibration and/or shock.
- 5 -No.VT325∗∗-OMF0002-B

VTA/VOA325 Series
3 Port Air Operated Valve
Precautions 3
Be sure to read this before handling products.
Operating Environment
4. The valve should not be exposed to prolonged
sunlight. Use a protective cover. Note that the
valve is not for outdoor use.
5. Remove any sources of excessive heat.
6. If it is used in an environment where there is
possible contact with oil, weld spatter, etc.,
exercise preventive measures.
1. Temperature of ambient environment
Use the valve within the range of the ambient temperature
specification of each valve. In addition, pay attention when
using the valve in environments where the temperature
changes drastically.
2. Humidity of ambient environment
• When using the valve in environments with low humidity,
take measures to prevent static.
• If the humidity rises, take measures to prevent the adhesion
of water droplets on the valve.
Maintenance
1. Perform maintenance and inspection
according to the procedures indicated in the
operation manual.
If handled improperly, human injury and/or malfunction or
damage of machinery and equipment may occur.
2. Removal of equipment, and supply/exhaust of
compressed air
Before components are removed, first confirm that measures
are in place to prevent workpieces from dropping, run-away
equipment, etc. Then, cut off the supply air and electric power,
and exhaust all air pressure from the system using the
residual pressure release function.
When the equipment is operated after remounting or
replacement, first confirm that measures are in place to
prevent the lurching of actuators, etc. Then, confirm that the
equipment is operating normally.
3. Low-frequency operation
Valves should be operated at least once every 30 days to
prevent malfunction. (Use caution regarding the air supply.)
4. If the volume of air leakage increases or the
valve does not operate normally, do not use
the valve.
Perform periodic maintenance on the valve to
confirm the operating condition and check for
any air leakage.
1. Drain flushing
Remove drainage from the air filters regularly.
2. Lubrication
Once lubrication has been started, it must be continued.
Use class 1 turbine oil (with no additives), VG32. If other
lubricant oil is used, it may cause a malfunction.
Please contact SMC for suggested class 2 turbine oil (without
additives), ISO VG32.
- 6 -No.VT325∗∗-OMF0002-B

VTA/VOA325 Series
Specific Product Precautions (1)
Be sure to read this before handling the products.
Breathing hole
1. The bottom of the solenoid valve has a breather hole for the
main valve. Take proper measures to prevent this hole from
being blocked as this will lead to a malfunction.
∗Ordinarily, when the solenoid valve is mounted on a metal
surface, it can breathe through the breather hole, via the
breather groove. However, in particular, if the surface to be
mounted is made of the rubber, the rubber could deform and
block the hole.
2. Make sure that dust and/or other foreign materials do not enter
the valve from the unused port (e.g. exhaust port).
Manifold specification
Manifold
For more than 4 stations, supply air from both P ports on . For
common exhaust type, exhaust from both R ports.
Mounting
When mounting valves on the manifold base, the mounting
orientation is decided. If it is mounted in the wrong direction,
connected equipment may malfunction.
Changing from N.C. to N.O.
The valves are assembled as N.C. valves at the time of shipment.
By removing the two retaining screws from the desired valves,
and rotating each valve body 180° and reassembling it on the
manifold base, it is possible to reassemble an N.C. valve as an
N.O. valve. (When doing so, make sure that a gasket is attached
to the mounting surface of the valve.) Properly tighten the screws.
The tightening torque of the retaining screws is 3 N·m.
A single valve unit port location
Bottom of the valve
Breathing hole of the main valve
Breathing hole
- 7 -
No.VT325∗∗-OMF0002-B

Troubleshooting
Countermeasures
If the countermeasures above are not effective, there may be aproblem with the valve. Stop using the valve
immediately.
If any of the examples below are applicable, there may be an internal problem with the valve. Stop using the
valve immediately.
5. Foreign matter such as condensate or dust has entered the product.
6. Other than those specified, if precautions on the operation manual apply.
* If the product has failed, then please return the valve as it is.
1. The oil supplied was not the specified type.
2. Lubrication was stopped during operation or lubrication was interrupted temporarily.
3. The product was directly exposed to water.
4. Severe impact was applied.
Stop the air and ensure that the bolts are correctly tighten
(6)
Replace the valve.
・If incorrect oil has been used for lubrication, remove the oil with air blow, and replace the valve with
a new one.
If alubricant is used in the system after replacing the valve, use turbine oil Class 1(with no additive)
ISO VG32.
・If there is alarge amount of condensate or condensate cannot be removed completely, mount an
auto drain or install a dryer and replace the valve.
(3)
(4)
Reduce the amount of lubrication to the amount at which the oil does not splash from the exhaust port
(R port).
(7)
(5)
No.
(1)
Countermeasures
Adjust the pressure so that pilot pressure is within the specified range during operation.
If air leakage is caused by foreign matter, remove foreign matter in the piping by air blow and replace
the valve.
Repair or replace the actuators.
(2)
(7)
Insufficient tightening of the bolt
Air leakage from the gasket
(2)
Sealing failure of actuators (such as
cylinder)
(5)
Worn spool valve
(2)
(6)
Sealing failure
Incomplete switch of spool valve
Lodging of foreign matter
Foreign matter caught in the spool valve
Excessive oil supply
The valve does not perform
the switching operation. Or,
switching is delayed.
Leakage from the
connecting port
(3)
(4)
Swollen spool valve
Operation failure
Decrease in pilot pressure
(1)
Perform troubleshooting with higher possibility based on the failure phenomenon.
Failure phenomenon
Possible causes
(2)
Countermeasures
- 8 - No.VT325∗∗-OMF0002-B

Revision history
□
AE A Renewal PT
A□ BE A Renewal WQ
1st printing: FT
4-14-1, Sotokanda, Chiyoda-ku, Tokyo 101-0021 JAPAN
Tel: + 81 3 5207 8249 Fax: [phone]
URL http://www.smcworld.com
Note: Specifications are subject to change without prior notice and any obligation on the part of the manufacturer.
© 2017 SMC Corporation All Rights Reserved
No.VT325∗∗-OMF0002-B