SMC Networks VPA31 5 Series User manual

Doc. no. VP3145-OMH0005-D
PRODUCT NAME
3 Port Air Operated Valve
MODEL/ Series/ Product Number
Series: VPA31∗5

Contents
Safety Instructions ---------------------------------------------------------------------------------- 2,3
Design -------------------------------------------------------------------------------------------------- 4
Selection ----------------------------------------------------------------------------------------------- 4
Mounting ----------------------------------------------------------------------------------------------- 4
Piping --------------------------------------------------------------------------------------------------- 5
Lubrication --------------------------------------------------------------------------------------------- 5
Air Supply --------------------------------------------------------------------------------------------- 5
Operating Environment ----------------------------------------------------------------------------- 5
Maintenance ------------------------------------------------------------------------------------------- 5
Specific Product Precautions ---------------------------------------------------------------------- 6,7
Trouble shooting -------------------------------------------------------------------------------------- 8
Remedy ------------------------------------------------------------------------------------------------- 9
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VP3145−OMH0005−D

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.
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VP3145-OMH0005-D

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.
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VP3145-OMH0005-D

Warning
Warning
Design / Selection
1. Confirm the specifications.
Products represented in this manual are designed only for use
in compressed air systems (including vacuum).
Do not operate at pressures or temperatures, etc., beyond the
range of specifications, as this can cause damage or
malfunction. (Refer to the specifications.)
Please contact SMC when using a fluid other than compressed
air (including vacuum).
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 (cover installation or
approach prohibition) to prevent potential danger caused by
actuator operation.
3. Holding pressure (including vacuum)
Since the valves are subject to air leakage, they cannot be
used for applications such as holding pressure (including
vacuum) in a pressure vessel.
4. Not suitable for use as an emergency shutoff
valve, etc.
The valves listed in this manual are not designed for safety
applications such as an emergency shutoff valve. If the valves
are used for the mentioned applications, additional safety
measures should be adopted.
5. Release of residual pressure
For maintenance purposes install a system for releasing
residual pressure.
6. Operation in a vacuum condition
When a valve is used for switching a vacuum, take measures
to install a suction filter or similar to prevent external dust or
other foreign matter from entering inside the valve. In addition,
at the time of vacuum adsorption, be sure to vacuum at all
times. Failure to do so may result in foreign matter sticking to
the adsorption pad, or air leakage causing the workpiece to
drop.
7. Regarding a vacuum switch valve and a
vacuum release valve
If a non-vacuum valve is installed in the middle of piping
system having a vacuum, the vacuum condition will not be
maintained. Use a valve designed for use under vacuum
condition.
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.
9 .Do not disassemble the product or make any
modifications, including additional machining.
Doing so may cause human injury and/or an accident.
When the product is disassembled for maintenance, refer to
“Overhaul / Cleaning / Addition of grease (VPA31*5V series:
Vacuum Specification)”.
Selection
1. Use in low temperature environments
Valve use is possible to temperature to 0oC. Take appropriate
measures to avoid freezing or congealing of drain, water, etc.
2. Pilot air
The pilot port should be pressurized by a compressed air at
the specified pressure.
3. Mounting orientation
Mounting orientation is free.
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.
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 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.
VPA31
∗
5 Series
Precautions for 3 Port Air Operated Valve
①
Be sure to read before handling.
Caution
- 4 - VP3145-OMH0005-D

Warning
Warning
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. Wrapping of pipe 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 pipe tape is
used, leave 1 thread ridges
exposed at the end of the
threads.
3. Connection of fittings
When screwing fittings into valves, tighten as follows.
Tightening Torque for Piping
Connection thread size (R, NPT)
Proper tightening torque (N·m)
1/8
3～5
3/8
15～20
1/2
20～25
3/4
28～30
1
36～38
1 1/4
40～42
1 1/2
48～50
2
48～50
Follow the procedure of the manufacturer when fittings other than
SMC is used.
1) If the fitting is tightened with excessive torque, a large amount
of sealant will seep out. Remove the excess sealant.
2) Insufficient tightening may cause seal failure or loosen the
threads.
3) For reuse
(1) Normally, fittings with a sealant can be reused up to 2 to 3
times.
(2) To prevent air leakage through the sealant, remove any
loose sealant stuck to the fitting by blowing air over the
threaded portion.
(3) If the sealant no longer provides effective sealing, wind
sealing tape over the sealant before reusing. Do not use any
form of sealant other than the tape type of sealant.
(4) Once the fitting has been tightened, backing it out to its
original position often causes the sealant to become
defective. Air leakage will occur.
4. Uni thread fittings
1) First, tighten the threaded portion by hand, then use a suitable
wrench to tighten the hexagonal portion of the body further at
wrench tightening angle shown below. For the reference value
for the tightening torque, refer to the table below.
Connection Female Thread: Rc, NPT, NPTF
Uni thread size
Wrench tightening angle
after tightened by hand
(deg)
Tightening torque
(N·m)
1/8
30 to 60
3 to 5
3/8
15 to 45
14 to 16
1/2
15 to 30
20 to 22
Connection Female Thread: G
Uni thread size
Wrench tightening angle
after tightened by hand
(deg)
Tightening torque
(N·m)
1/8
30 to 45
3 to 4
3/8
15 to 30
8 to 9
1/2
15 to 30
14 to 15
2) The gasket can be reused up to 6 to 10 times. It can be
replaced easily when it has sustained damage. Abroken gasket
can be removed by holding it and then turning it in the same
direction as loosening the thread. If the gasket is difficult to
remove, cut it with nippers, etc. In such a case, use caution not
to scratch the seat face because the seat face of the fitting’s
45° gasket is the sealing face.
5. Piping to products
When piping to a product, refer to the operation manual to
avoid mistakes regarding the supply port, etc.
Lubrication
This is a valve which requires lubrication. Be
sure to lubricate it for operation.
It may cause problems such as damage and
malfunction of the valve if it is not lubricated.
A valve of vacuum specification needs overhaul
for cleaning and addition of grease because it
cannot be lubricated without it. (Refer to page 8.)
1) If a lubricant is used in the system, use class 1 turbine oil (no
additive), ISO VG32.
2) Please contact SMC regarding class 2 turbine oil (with
additives), ISO VG32.
Lubrication amount
If too much oil is supplied, the oil will be accumulated in the
product, causing malfunction or response delay.
Air Supply
1. Use clean air.
Do not use compressed air that contains chemicals, synthetic
oils including organic solvents, salt or corrosive gases, etc., as
it can cause damage or malfunction.
1. Install an air filter.
Install an air filter upstream near the valve. Select an air filter
with a filtration size of 5 ㎛or smaller.
2. 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 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.
VPA31
∗
5 Series
Precautions for 3 Port Air Operated Valve
②
Be sure to read before handling.
Caution
Caution
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Warning
Warning
Air Supply
3. If excessive carbon powder is seen, 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 SMC’s Best Pneumatics
catalog.
Operating Environment
1. Do not use in an atmosphere having 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.
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 a waterdrop, 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
If the humidity rises, take measures to prevent the adhesion
of water droplets on the valve.
Maintenance
1. Perform maintenance inspection according to
the procedures indicated in the operation
manual.
If handled improperly, malfunction and damage of machinery
or equipment may occur.
2. Removal of equipment, and supply/exhaust of
compressed air
When components are removed, first confirm that measures
are in place to prevent workpieces from dropping, run-away
equipment, etc. Then, cut off the supply pressure and electric
power, and exhaust all compressed air 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 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.
Caution
Caution
Caution
VPA31
∗
5 Series
Precautions for 3 Port Air Operated Valve
③
Be sure to read before handling.
- 6 - VP3145-OMH0005-D

Other Precautions
1. Pressure balance among each port
This valve is pressure-unbalanced type. Operate it within
this pressure range: IN ≧OUT ≧EXH. If not operated in
the range, the valve will malfunction.
2. Use as 2 port valve
1) Plug EXH port in case of pressure-in and plug IN port in
case of vacuum use.
2) This valve has slight air leakage and can not be used for
such purposes as holding air pressure (including vacuum)
in the pressure container.
3. Piping (Vacuum Use)
1) Piping in general:
Vacuum pump/
Blower
Vacuum pad/
Tank
Plug (2 port valve)
IN port = Air releasing
Air pressure-in
EXH port = (Suction side)
OUT port = (Load side)
VPA31
∗
5 Series
Specific Product Precautions
Be sure to read before handling
.
Caution
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1) How to overhaul (Remove air supply before starting disassembly.)
Remove the four hexagon socket head cap screws○
11E
A and take the housing.
The guide ringA○
9E
Acan be found on the body, and take it away with a flat head screw driver to take the internal parts away.
2) How to add grease
Take the parts off and wipe off the dust adhered on them.
Wipe off the dust inside the bodyA○
1E
A, too.
Take the O-rings A○
5E
Aand A○
7E
Ain the sliding part off of the spool valveA○
6E
A, wipe them to clean and apply grease.
Apply grease to the portion A of the spool valveA○
6E
A, internal surface of the guide ring and portions B, C, D of the bodyA○
1E
A, too.
Note 1) Do not wash the O-ring and the spool valve with organic solvent or such.
Note 2) It is suggested to use the silicone grease “G-40M” made by Shin-Etsu Chemical Co., Ltd.
3) Overhaul
1. Insert the elementA○
2E
Aand the spring washerA○
3E
Ain the direction that the figure shows.
2. Insert the spool valveA○
6E
Aand the guide ringA○
9E
Atogether into the bodyA○
1E
A.
*Be sure to have a performance inspection and an air leakage test after overhaul of the valve.
Performance deterioration, damage and such caused by overhaul for cleaning are out of SMC’s guarantee.
(Contact SMC for repair if it needs to be guaranteed.)
Overhaul, Cleaning, Addition of Grease (VPA31
∗
5V Series: Vacuum Specification)
VPA31
∗
5 Series
Specific Product Precautions
②
Be sure to read before handling
.
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Trouble shooting
Remedy
（Next page）
Foreign matter caught in
sliding area
①
Seal failure
Leakage from
Intrusion of foreign matter
⑤
exhaust port
According to the failure, check the cause of the failure from which seems to effect the
failure more than the other and devise a countermeasure.
Failure
Cause
Operation failure
Valve would not
be switched.
Seal failure at
⑥
actuator (such as cylinder)
Inefficient supply pressure
④
Inflow of drain
②
Inefficient lubrication
③
- 9 - VP3145-OMH0005-D

Remedy
No. Remedy
①Replace the valve.
- If the lubrication oil was incorrect, remove the oil by air blow and replace the valve.
Lubricate turbine oil class 1 (ISO VG32) surely after replacing the valve.
③Check the lubrication amount is correct or not.
Check the pressure is within the specified pressure range. Check the pressure is
dropped or not when the valve is worked.
⑤Replace the valve after removing foreign matter in the pipe by such as air blow.
⑥Fix or replace the actuator.
1. Oil other than the specified one has been lubricated.
2. Lubrication has been stopped intermediately, or lubrication was suspended temporary.
3. Water splashed directely.
4. Strong impact was given.
5. Foreign matter such as drain and particle invaded.
∗Return us the failure valve in just the state when the failure occurred to the valve.
②
④
If no improvement is achieved in spite of the above countermeasure, inside of the valve may have some
failure. In this case, stop using the valve immediately.
If any of followings are carried out, inside of the valve may have some failure. In this case, stop using
the valve immediately.
6. Prohibited way of using the valve which is written at ''Precautions'' section in this operation
manual was carried out excluding above-mentioned.
- When a large quantity of drain is given and cannot carry out drain omission surely,
install either an auto-drain or a dryer.The valve should be replaced.
- 10 - VP3145-OMH0005-D

Revision history
□
DE ARenewal 2018.8
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.
© 2018 SMC Corporation All Rights Reserved
VP3145−OMH0005−D