SMC Networks ASN2 Series User manual

Doc. no. AS＊-OMP0006-B
PRODUCT NAME
METERING VALVE WITH SILENCER
MODEL / Series / Product Number
ASN2 Series

Contents
1．Safety Instructions 2 ～3
2．Specific Product Precautions 4 ～6
3．Application 7
4．Specifications 7
5．Troubleshooting 7
6．Construction 7
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Metering Valve with Silencer
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" and
"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 location 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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Metering Valve with Silencer
Safety Instructions
Caution
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.
LimitedwarrantyandDisclaimer/ComplianceRequirements
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.
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 SMC 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
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 regulations of the countries involved in the transaction. Prior to the
shipment of a SMC product to another country, assure that all local governing that export are
known and followed.
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.
! 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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2. Specific Product Precautions
Warning
(1) Confirm the specifications.
Products represented in this catalog are 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.(Refer to the specifications.)
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) Products mentioned in this catalog are not
designed for use as stop valves with zero air
leakage.
A certain amount of leakage is allowed in the
products’specifications. Tightening the needle to
reduce leakage to zero may result in equipment
damage.
(3) Do not disassemble the product or make
any modifications, including additional
machining.
Doing so may cause human injury and/or injury an
accident.
(4) The flow rate characteristics for each
product are representative values.
The flow rate characteristics are characteristics of
each individual product. Actual values may differ
depending on the piping, circuitry, pressure
conditions, etc. Also, depending on product
specifications, there may be variations in the zero
needle rotations position of the flow rate
characteristics.
(5) Check if PTFE can be used in the
application.
PTFE powder (Polytetrafluoroethylene resin) is
Included in the seal material of the male thread
type piping taper thread. Confirm that the use of it
will not cause any adverse effects on the system.
Please contact SMC if the Safety Data
Sheet (SDS) is required.
(6) Example of inapplicable circuits
Warning
(1) Operation Manual
Install the product and operate it only after reading
the operation manual carefully and understanding its
contents. Also, keep the manual where is can be
referred to as necessary.
(2) Ensure sufficient space for maintenance
activities.
When installing the products, allow access for
maintenance and inspection.
(3) Confirm that the lock nut is tightened.
A loose lock nut may cause speed changes in the
actuator.
(4) Check the number of opening and closing
rotations of the needle valve.
It is not possible to remove the needle valve
completely, over rotation will cause damage to the
product.
(5) Do not use tools, such as pliers, to rotate
the knob.
This can cause the idle rotation of the knob or
damage.
(6) Tighten threads with the proper tightening
torque.
When installing the products, follow the listed
torque specifications.
(7) Adjust the needle by opening the needle
slowly after having closed it completely.
Loose needle valves may cause unexpected
sudden actuator extension. When a needle valve is
turned clockwise, it is closed and cylinder speed
decreases. When a needle valve is turned
counterclockwise, it is open and cylinder speed
increases.
(8) Do not apply excessive force or shock to the
body with an impact tool.
This can cause damage or air leakage.
(9) To install/remove the flow control equipment,
use an appropriate wrench to tighten/loosen
the supplied nut on body B as close to the
thread as possible.
Do not apply torque at other points, as the product
may be damaged.
(10)
Design/ Selection
Mounting

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Caution
(1) First, tighten the fitting by hand, then use a
suitable wrench to tighten the hexagonal
portion of the body a further two or three turns.
For the reference value for the tightening
torque, refer to the table below. Check the
dimensions of each product for the width
across flats.
(2) M5 and 10-32 UNF
First, tighten it by hand, then give it an additional
1/6 turn to 1/4 turn with a wrench. The reference
value for the tightening torque is 1 to 1.5N・m.
※Excessive tightening may damage the thread
portion or deform the gasket and cause air leakage.
If the screw is too shallowly screwed in, it may come
loose or air may leak.
(3)Chamfered female thread size of the
connection thread M5, 10-32UNF
In compliance with ISO16030 Standards (air
pressure fluid dynamics –connection –ports and
stud ends), the chamfered thread sizes shown
below are recommended.
(4) The proper tightening torques for hexagon
lock nuts are shown in the table below. For
standard installation, turn 15 to 30°using a
tool, after fastening by hand.
Pay attention not to over tighten the product for
the width across flats.
Caution
(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.
Caution
(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.
Warning
(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 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 and allow
the condensation to enter the compressed air
lines. This causes 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 Best
Pneumatics No.6 catalog.
(4) Use clean air.
Do not use compressed air that contains
chemicals, synthetic oils that include organic
solvents, salts or corrosive gases, etc., as it can
cause damage or malfunction.
Caution
(1) Install an air filter.
Install an air filter upstream near the valve.
Select an air filter with a filtration size of 5μm 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 the malfunction of
pneumatic equipment, such as flow control
equipment. Therefore, take appropriate
measures to ensure air quality, such as by
providing an aftercooler, air dryer, or water
separator.
(3) Ensure that the fluid and ambient
temperatures air within the specified
range.
If the fluid temperature is 5℃or less, the
moisture in the circuit could freeze, causing
damage to the seals or leading to equipment
malfunction. Therefore, take appropriate
measures to prevent freezing. For compressed
air quality, refer to the Best Pneumatics No.6
catalog.
Female thread size
Chamfered port size ΦD
(Recommended value)
M5
3.1 to 3.4
10-32UNF
5.1 to 5.3
Air Supply
Piping
Mounting
Piping

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Warning
(1) Do not use in an atmosphere containing
corrosive gases, chemicals, sea water, water
steam, or where there is direct contact with
any of these.
Refer to each construction drawing for information
on the materials of flow control equipment.
(2) Do not expose the product to direct sunlight
for an extended period of time.
(3) Do not use in a place subject to heavy
vibration and/or shock.
(4) Do not mount the product in locations where
it is exposed to radiant heat.
Warning
(1) Perform maintenance and inspection
according to the procedures indicated in
the operation manual.
If handled improperly, malfunction or damage of
machinery and equipment may occur.
(2) Maintenance work
If handled improperly, compressed air can be
dangerous. Assembly, handling, repair and
element replacement of pneumatic systems
should be performed by a knowledgeable and
experienced person.
(3) Drain flushing
Remove drainage from air filters regularly.
(4) 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 pressure and electric power, and exhaust
all compressed air from the system using the
residual pressure release function.
When machinery is restarted, proceed with caution
after confirming that appropriate measures are in
place to prevent sudden movement.
Operating environment
Maintenance

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3. Application
This product is designed to control the speed of a pneumatic actuator.
4. Specifications
WORKING FLUID
AIR
WORKING PRESS.RANGE
0～1MPa
PROOF PRESS
1.5MPa
AMBIENI TEMP. AND WORKING FLUID TEMP.
-5～60℃(NO FREEZING)
5．Troubleshooting
Trouble
Possible cause
Countermeasures
The speed (flow
rate) cannot be
controlled.
Dust inside
Fully open the needle and apply air blow
from the screw. If the problem in not
solved even after air blow, install an air
filter to the piping, and replace the
product with a new one.
6．Construction
ASN2-M5,U10/32 ASN2-01～04
ASN2-N01～N04
No. Description Material
1
Handle PBT
2
Needle Brass
3
Lock nut Steel wire
4
Needle guide Brass
5
Washer Steel
6
Cover PE
7
O ring NBR
8
Sponge PVA Sponge
9
Body B Brass
10
Gasket NBR/Stainless
Remarks
Electroless nickel plating
Electroless nickel plating
M5,U10/32
Electroless nickel plating

S
Revision history
4-14-1, Sotokanda, Chiyoda-ku, Tokyo 101-0021 JAPAN
Tel: + 81 3 5207 8249 Fax: [phone]
URL https://www.smcworld.com
Note: Specifications are subject to change without prior notice and any obligation on the part of the manufacturer.
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