SMC Networks AKP Series User manual

PRODUCT NAME
Pilot Check Valve Compact Type
MODEL/ Series/ Product Number
AKP- ＊＊＊＊ - ＊
Doc. no. DOC1013639-2
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Contents
1. Safety Instructions 2 ～ 3
2. Specific Product Precautions 4 ～ 10
3. Application 11
4. Specifications 11
5. Malfunctions and Countermeasures 11
6. Construction 12 ～ 14
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Pilot Check Valve Compact Type
AKP Series
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 and safety requirements for systems and their components
ISO 4413: Hydraulic fluid power - General rules and safety requirements for systems and their components
IEC 60204-1: Safety of machinery - Electrical equipment of machines - Part 1: General requirements
ISO 10218-1: Robots and robotic devices - Safety requirements for industrial robots - Part 1:Robots
etc.
Danger
Danger
indicates a hazard with a high level of risk which, if not avoided, will result
in death or serious injury.
Warning
Warning
indicates a hazard with a medium level of risk which, if not avoided, could
result in death or serious injury.
Caution
Caution
indicates a hazard with a low level of risk which, if not avoided, could result
in minor or moderate 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. Our products cannot be used beyond their specifications.
Our products are not developed,
designed, and manufactured to be used under the following conditions or
environments. Use
under such conditions or environments is not covered.
1. Conditions and environments outside of the given specifications, or use outdoors or in a place exposed to
direct sunlight.
2. Use for nuclear power, railways, aviation, space equipment, ships, vehicles, military application, equipment
affecting human life, body, and property, fuel equipment, entertainment equipment, emergency shut-
off
circuits, press clutches, brake circuits, safety equipment, etc., and use for applications that do
not conform
to standard specifications such as catalogs and operation manuals.
3. Use for interlock circuits, except for use with double interlock such as installing a mechanical protection
function in case of failure. Please periodically inspect the
product to confirm that the product is operating
properly.
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Pilot Check Valve Compact Type
AKP Series
Safety Instructions
Caution
We develop, design, and manufacture our products to be used for automatic control equipment, and
provide them for peaceful use in manufacturing business.
Use in non-manufacturing business is not covered.
Products we manufacture and sell cannot be used for the purpose of transactions or certification specified
in the Measurement Act.
The new Measureme
nt Act prohibits use of any unit other than SI units in Japan.
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.
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.
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 securit
y 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 followed.
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2. Specific Product Precautions
Warning
(1) Confirm the specifications.
The products are designed to be used in
compressed air systems (including vacuum)
only.
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 (including vacuum).
We do not guarantee against any damage if the
product is used outside of the specifications
range.
(2) Do not disassemble the product or make any
modifications, including additional
machining.
Doing so may cause human injury and/or an
accident.
(3) Sonic conductance (C) and critical pressure
ratio (b) values for products are
representative values.
(4) Check if PTFE can be used in 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 effect on the system.
Please contact SMC if the Safety Data Sheet
(SDS) is required.
(5) The pilot check valve is a product aimed at
the control of the actuator via a temporary
intermediate stop.
The pilot check valve is used for temporarily
stopping the actuator. Until a pilot signal is input,
the valve shuts off the flow path from 2 to 1 and
the actuator stops. When a pilot signal is input,
the flow path from 2 to 1 is opened. When the
residual pressure exhaust button is operated, all
flow paths (2 to 1, 21, and exhaust port) are
opened.
Warning
(6) The product cannot be used for accurate and
precise intermediate stop of the actuator.
Due to the compressibility of air as a fluid, the
actuator will continue to move until it reaches a
position of pressure balance, even though the
pilot check valve closes with an intermediate
stop signal.
(7) The product cannot be used for retention of
the stop position for long hours.
Pilot check valve and actuators are not
guaranteed for zero air leakage. Therefore, it is
sometimes not possible to hold a stop position
for extended period of time. In the event that
holding for an extended time is necessary, a
mechanical means for holding should be
devised.
(8) When “AKP-*-M5” or “AKP-*-U10” is used,
pay attention to the residual pressure on the
port 1 side.
Due to the residual pressure on the port 1 side,
the responsiveness of the intermediate stop of
the actuator may become slower. Use “AKP-*-
M5” or “AKP-*-U10” in a circuit in which an
exhaust center valve is used so that no residual
pressure is generated on the port 1 side.
(9) Pay attention to the residual pressure within
the actuator at the time of intermediate stop.
When the actuator is stopped at the intermediate
position by this product, there may be pressure
contained inside the actuator, therefore the
actuator may suddenly move when the residual
pressure is released. Before operating the
residual pressure exhaust button, confirm that
the surrounding area is secure from any
potential hazards or accidents occurring.
(10) Use this product after checking the
surrounding areas in advance before the
release of residual pressure.
The actuator may move at a speed quicker
than the intended speed from the original circuit
set up when exhausting from the residual
pressure release. Confirm this speed will not
create additional hazards and pay attention to
the air discharged from the exhaust port.
Design/ Selection
Residual pressure
exhaust button (ø2.9)
Exhaust Port
Design/ Selection
Exhaust
Port
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Warning
(11) Pay attention to the motion of the actuator
at the time of release of the residual
pressure.
When operating the residual pressure exhaust
button or conducting maintenance or
inspection, the actuator may start moving due
to the residual pressure. Take appropriate
measures in advance to prevent an actuator
movement from posing a hazard.
Also pay attention to the operation speed and
the movement of the cylinder during exhaust.
When an exhaust center valve is used on the
actuator supply side (Figure A below), the
residual pressure is released from port 1, 21,
and the exhaust port. However, when using a
closed center valve like the example shown in
Figure B below, air is discharged only from port
21 and the exhaust port. Use “AKP-*-M5” or
“AKP-*-U10” in a circuit with an exhaust center
valve.
For the moving direction of the actuator against
the corresponding exhaust side, refer to the
figure below.
*Use “AKP-*-M5” or “AKP-*-U10” in a circuit with an
exhaust center valve.
Warning
* “AKP-*-M5” and “AKP-*-U10” cannot be used in a circuit in
which only a closed center valve is used. When you wish to
use “AKP-*-M5” or “AKP-*-U10” together in a circuit with a
closed center valve, please contact SMC.
(12) Push the residual pressure exhaust button
all the way to the end position by using a
tool.
Push the residual pressure exhaust button all
the way to the end position by using a tool
having a tip diameter of φ2.8 or below. See the
table below for the depth and force to push the
tool. The higher the residual pressure, the more
force is needed to press the override button
completely.
Operating force [N]
(reference value)
AKP-*-M5/U10 5.3 to 8.2 3.5
AKP-*-*01 5.1 to 11.9 3.9
AKP-*-*02 6.7 to 19.5 3.8
AKP-*-*03 10.6 to 34.4 4.7
AKP-*-*04 17.1 to 54.4 5.8
Part number Operating depth
[mm]
(13) After operating the residual pressure
exhaust button, confirm that the button has
returned to the normal position.
Make sure that the residual pressure exhaust
button has returned to the end face of the
product before operating again. If the button
cannot return to the normal position, the
intermediate stop function of the actuator will
not work. Therefore, replace the product with a
new one.
Moves to the
extended end side.
Moves to the
retracted end side.
Exhaust side
Exhaust side
Figure A: Example of piping using exhaust center valve
Figure B: Example of piping using closed center valve
(Recommended example)
Design/ Selection
Moves to the
extended end side.
Moves to the
retracted end side.
Exhaust side
Exhaust side
Design/ Selection
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Warning
(14) Pay attention to the motion of the actuator
at the time of restart after the release of
residual pressure.
When restarting the product after releasing the
residual pressure, check the initial driving
direction, confirm that the work area is secured,
and then restart the product. Failure to follow
this instruction may cause the actuator to
suddenly move.
(15) When the product is used in a balance
control circuit, the check valve may not be
released even when the pilot pressure is
50% of the operating pressure. In this case,
obtain the pilot pressure from a position so
that the pilot pressure is equivalent to the
operating pressure.
When using the product at the minimum
operating pressure, set the pilot pressure to
0.1 MPa or higher. For AKP-*-M5/U10 pilot
check valve, pilot pressure to 0.15 MPa or
higher.
(16) As a reference, we have confirmed through
our durability tests that the check valve has
a durability against 10 million cycles of ON
and OFF operations and the residual
pressure exhaust button has a durability
against 10,000 cycles of operation at the
maximum operating pressure.
However, note that the tests were
conducted under limited conditions.
(17) In the following cases, malfunctioning or
noise due to oscillation may occur.
- When the differential pressure between the
port 1 side and port 2 side is smaller than the
minimum operating pressure
- When the IN side piping of the product or the
effective area of the directional control valve is
smaller than that of the product
- When the pressure drop on the port 1 side is
slower than that of the port 2 side during
operation of the product
- When the supply pressure at the port 21 is
reduced (Refer to the piping diagram below.)
- When the port 1 side piping (tube) is bent or
crushed
Warning
Warning
(1) Operation Manual
Install the products and operate it 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
proper torque.
(4) Use R external threads with Rc internal
threads and NPT external threads with NPT
internal threads and G external threads with
G internal threads.
(5) Check piping directions before mounting.
Connect the inlet to the directional control valve
and the outlet to the actuator.
(6) Do not apply excessive force or shock to the
body or fittings with an impact tool.
It can cause damage or air leakage.
(7) For handling One-touch fittings, refer to the
Fittings and Tubing Precautions.
Mounting
Recommended
NG
Design/ SelectionDesign/ Selection
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Warning
(8) Pay attention to the method of mounting on
the cylinder.
For the horizontal type, a hexagon wrench
needs to be used. The product cannot be
mounted with an open-end wrench. For the
mounting of the vertical type, an open-end
wrench needs to be used. Note that the
mounting method differs between the vertical
type and the horizontal type.
(9) Conduct mounting and removal of the
vertical type by holding the width across
flats of the body B and turning it by using an
appropriate wrench.
Do not apply torque at other points as the
product may be damaged. Rotate Body A
manually for positioning after installation.
(10) To install and remove the product with
hexagonal hole, use an appropriate hex key
and push it into the hexagon hole of the
stud.
Do not apply torque at other points as the
product may be damaged. Rotate Body A or B
manually for positioning after installation. Refer
to the applicable dimension of the hexagon
wrench.
Metric [mm] Imperial [Inch]
M5, 10-32UNF 2.5 -
R1/8, G1/8 6 -
NPT1/8 - 7/32"
R1/4, G1/4 8 -
NPT1/4 - 5/16"
R3/8, G3/8 10 -
NPT3/8 - 3/8"
R1/2, G1/2 10 -
NPT1/2 - 3/8"
Connection
Thread
Hex Key (Nominal)
(11) Do not use the product in application that
involves continuous rotation. Do not use
the product in a manner that applies a
moment load.
Failure to follow these instructions may cause
the fitting or product to be damaged.
Caution
(1) For M5, 10-32UNF
① Tightening method
First, tighten it by hand, then give it an additional
1/6 turn to 1/4 turn with a wrench. A reference
value for the tightening torque is 1 to 1.5 N·m.
Note) 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.
② Chamfered area for female thread
Conforming to ISO 16030 (air pressure fluid
dynamics –connection –ports and stud ends),
the chamfered dimensions shown in the table
below are recommended.
M5
10-32UNF
Female thread
size
Chamfered port size φD
（
Recommended value
）
5.1 to 5.4
5.0 to 5.3
(2) For R, NPT, G thread
① Tightening method
To tighten a screw on the vertical type, first
tighten it by hand and then hold the width across
flats of the body B and turn it by using an
appropriate wrench. To tighten a screw on the
horizontal type, tighten it by hand and then insert
an appropriate hexagon wrench to the
hexagonal socket of the stud and turn it.
Refer to the reference values in the table below
for the tightening torque.
1/8 3 to 5
1/4 8 to 12
3/8 15 to 20
1/2 20 to 25
Connection thread
size
Tightening Torque
(N
・
m)
② Chamfered area for female thread
By chamfering as shown in the following table,
machining of threads is easier and effective for
burr prevention.
Rc NPT G Face seal
1/8 10.2 to 10.4 10.5 to 10.7 9.8 to 10.2
1/4 13.6 to 13.8 14.1 to 14.3 13.3 to 13.7
3/8 17.1~17.3 17.4~17.6 16.8~17.2
1/2 21.4~21.6 21.7~21.9 21.0~21.4
Chamfered port size φD
（
Recommended value
）
Connection
Thread size
*G thread (face seal) complies with ISO16030-
2001.
Mounting
Body B
Body A
Stud
End Body
*Illustrations of vertical type (left)
and horizontal type (right) products
Mounting
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Caution
(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 loosen the
threads, or cause air leakage.
(3) Reuse
① Normally, fittings with a sealant can be reused
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, wrap sealing tape over the sealant
before reusing. Do not use the sealant in any
form other than a tape type.
(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
(5) Use R external threads with Rc internal
threads and NPT external threads with NPT
internal threads.
Caution
(1) Refer to the Fittings & Tubing Precautions for
handing One-touch fittings.
(2) 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.
(3) Winding of sealant tape
When screwing together pipes and fittings, etc.,
be certain that chips from the pipe threads and
sealing material do not get inside the pipe.
Also, when the sealant tape is used, leave
approx. 1 thread ridges exposed at the end of
the threads.
Caution
(1) Connection and disconnection of tube from
one-touch fitting
① Installation of tube
1) Cut the tube perpendicularly, being careful not
to damage the external surface. Use an SMC
tube cutter TK-1, 2, 3 or 6. Do not cut the tubing
with pliers, nippers, scissors, etc., otherwise
the tubing will be deformed and problems may
result.
2) The outside diameter of the polyurethane
tubing swells when internal pressure is applied
to it. Therefore, it may be impossible to re-
insert the tubing into One-touch fittings. Check
the tubing outside diameter, and when the
accuracy of the outside diameter is +0.07mm
or larger for φ2, and +0.15mm or larger for
other sizes, re-insert it into the One-touch
fitting without cutting the tube. When the
tubing is re-inserted into the One-touch fitting,
confirm that the tubing goes through the
release button smoothly.
3) Grasp the tubing, and slowly push it straight (0
to 5°) into the One-touch fitting until it comes to
a stop.
4) Pull the tubing back gently to make sure it has
a positive seal. Insufficient installation may
cause air to leak or the tubing to release.
As a guide for checking if the tubing is pulled
out or not, refer to the following table.
② Removal of the tube
1) Push the release button flange evenly and
sufficiently to release the tube. Do not push
in the tubing before pressing the release button.
2) Pull out the tubing while keeping the release
button depressed. If the release button is not
held down sufficiently, the tubing cannot be
withdrawn.
3) To reuse the tubing, remove the previously
lodged portion of the tubing. If the lodged
portion is left on without being removed, it may
result in air leakage and make the removal of
the tubing difficult.
Piping Threads with Sealant
Piping
Precautions for One-Touch Tube Fittings
Piping
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Caution
(2) Connection of the metal rod accessories
Do not use tube, resin plug, reducer, etc. after
connecting a fitting with a metal rod (KC series,
etc.) to a One-touch fitting. This can cause the
disconnection of tube.
(3) When mounting the tube, resin plug or metal
rod, do not press the release button.
Do not press the release button unnecessarily
before mounting tubing, resin plugs and metal
rods. This can cause the disconnection of tube.
(4) When using a tubing other than from SMC,
confirm that the tube material and the O.D.
accuracy satisfy the following specifications.
1) Nylon tube ±0.1 mm max.
2) Soft nylon tube ±0.1 mm max.
3) Polyurethane tube +0.15 mm at max.
Within -0.2 mm
Do not use the tubing which does not satisfy the
specified tubing O.D. accuracy, or if the tubing
has a different I.D., material, hardness, or
surface roughness from those of SMC's tubing.
If you have any questions, please consult SMC.
Failure to satisfy the specifications may lead to
difficulty in connecting the tubing, leakage,
disconnection of the tubing, or fitting damage.
(1) When connecting piping to the One-touch
fitting, use a pipe length with sufficient
margin, in accordance with the piping
conditions shown in Figure 1.
Also, when using a tying band, etc., to bind the
piping together, make sure that external force
does not come to bear on the fitting.
(see Figure 2)
Unit:mm
φ4, φ5/32"
56 or more 44 or more 26 or more 20 or more
φ6
84 or more 66 or more 39 or more 30 or more
φ1/4"
89 or more 70 or more 57 or more 32 or more
φ8, φ5/16”
112 or more 88 or more 52 or more 40 or more
φ10
140 or more 110 or more 69 or more 50 or more
φ12
168 or more 132 or more 88 or more 60 or more
Tubing size Straight-line
length
Mounting pitch A
Nylon
tube
Soft nylon
tube
Polyurethane
tube
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 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 and
allow the condensation to enter the compressed
air lines. This causes 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 SMC catalog
"Compressed Air Purification System".
(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.
Caution
(1) Install an air filter.
Install an air filter upstream near the valve.
For the filtration rating, select 5 μm or below, or
select a rating equivalent to or lower than ISO
8573-1:2010 [6:4:4]
*
.
*This is equivalent to the filtration performance
achieved when an air filter is attached for inlet
side compressed air with purity class of [7:4:4].
(2) Ensure that the fluid and ambient
temperatures are 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 SMC catalog
"Compressed Air Purification System".
Recommended Piping Conditions
Piping
Air Supply
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