Datasheet

Series VX21/22/23
Specific Product Precautions 1
Be sure to read before handling.
Refer to back cover for Safety Instructions, “Handling Precautions for SMC Products”
(M-E03-3) and the Operation Manual for 2 Port Solenoid Valves for Fluid Control
Precautions. Please download it via our website, http://www.smcworld.com
Design
Design
Selection
Warning
1. Cannot be used as an emergency shutoff valve, etc.
The valves presented in this catalogue are not designed for
safety applications such as an emergency shutoff valve. If the
valves are used in this type of system, other reliable safety
assurance measures should also be adopted.
2. Extended periods of continuous energization
The solenoid coil will generate heat when continuously
energized. Avoid using in a tightly shut container. Install it in a
well-ventilated area. Furthermore, do not touch it while it is
being energized or right after it is energized.
3. Liquid rings
In cases with a flowing liquid, provide a bypass valve in the
system to prevent the liquid from entering the liquid seal circuit.
4. Actuator drive
When an actuator, such as a cylinder, is to be driven using a
valve, take appropriate measures to prevent potential danger
caused by actuator operation.
5. Pressure (including vacuum) holding
It is not usable for an application such as holding the pressure
(including vacuum) inside of a pressure vessel because air
leakage is entailed in a valve.
6. When the conduit type is used as equivalent to an
IP65 enclosure, install a wiring conduit, etc.
7.
When an impact, such as water hammer, etc., caused
by the rapid pressure fluctuation is applied, the
solenoid valve may be damaged. Give an attention to it.
Selection
Warning
1. Fluid
1) Type of fluid
Before using a fluid, check whether it is compatible with the
materials of each model by referring to the fluids listed in this
catalogue. Use a fluid with a kinematic viscosity of 50 mm
2
/s
or less. If there is something you do not know, please contact
SMC.
2) Flammable oil, Gas
Check the specifications for leakage in the interior and/or
exterior area.
3) Corrosive gas
Cannot be used since it will lead to cracks by stress corrosion
or result in other incidents.
4) Depending on water quality, a brass body can cause
corrosion and internal leakage may occur. If such abnormali-
ties occur, exchange the product for a stainless steel body.
5) Use an oil-free specification when any oily particle must not
enter the passage.
6) Applicable fluid on the list may not be used depending on the
operating condition. Give adequate confirmation, and then
determine a model, just because the compatibility list shows
the general case.
2. Fluid quality
<Air>
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.
2) Install an air filter.
Install an air filter close to the valve on the upstream side. A
filtration degree of 5 μm or less should be selected.
3) Install an aftercooler or air dryer, etc.
Compressed air that contains excessive drainage may cause
malfunction of valves and other pneumatic equipment. To
prevent this, install an aftercooler or air dryer, etc.
4) If excessive carbon powder is generated, eliminate it by
installing a mist separator on the upstream side of
valves.
If excessive carbon powder is generated by the compressor,
it may adhere to the inside of the valves and canse a
malfunction.
<Vacuum>
Please be aware that there is a range of pressure that can be
used.
Vacuum piping direction: if the system uses a vacuum pump,
we ask that you install the vacuum pump on the secondary side.
Also, install a filter on the primary side, and be careful that no
foreign material is picked up.
Please replace the valve after operating the device
approximately 300,000 times.
Atmospheric pressure
Air pressure
Hydraulic pressure
Low
vacuum
Medium
vacuum
High
vacuum
Ultra high
vacuum
Extreme
high
vacuum
10
-12
10
-11
10
-10
10
-9
10
-8
10
-7
10
-6
10
-5
10
-4
10
-3
10
-2
10
-1
11010
2
10
-12
10
-11
10
-10
10
-9
10
-8
10
-7
10
-6
10
-5
10
-4
10
-3
10
-2
10
-1
110
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
Pa
Torr
(mmHg)
Differential
pressure
Drying
Discharge/Plasma
Vapor
deposition
<Accelerator, Electron microscope>
Surface
physics
Charged
particle beam
<Suction filtration, Vacuum bottle set, Suction cup>
Neon tube/Fluorescent light
37