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VN-OMA0013-D
Warning
Warning
Warning
Design
1. Cannot be used as an emergency shutoff
valve, etc.
The valves presented in this catalog are not designee 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. Ensure sufficient space for maintenance ac-
tivities.
When installing the products, allow access for maintenance.
3. Liquid rings
In cases with a flowing liquid, provide a by-pass 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 leakage
is entailed in a valve.
6. When an impact, such as water hammer, etc.,
caused by the rapid pressure fluctuation is
applied, the valve may be damaged. Give an
attention to it.
Selection
1. Confirm the specifications.
Give careful consideration to the operating conditions such as
the application, fluid and environment, and use within the
specified operating ranges in this catalog.
2. Fluids
1) Type of fluids
Before using a fluid, confirm whether it is compatible with the
materials from each model by referring to the fluids listed in
the catalog.
If there is something you do not know, please contact SMC.
2) Corrosive gas
Cannot be used since it will lead to cracks by stress corrosion
or result in other incidents.
3)
When a bronze body is used, then depending on water quality,
corrosion and internal leakage may occur. If such abnormali-
ties occur, exchange the product for a stainless steel body.
3. Fluid quality
The use of a fluid that contains foreign matter can cause prob-
lems such as malfunction and seal failure by promoting wear of
the valve seat, and by transformation of valve element, etc.
Install a suitable filter (strainer) immediately upstream from the
valve. As a general rule, use 80 to 100 mesh.
When used to supply water to boilers, substances such as
calcium and magnesium which generate hard scale and sludge
are included. Since this scale and sludge can cause the valve to
malfunction, install water softening equipment, and a filter
(strainer) directly upstream from the valve to remove these
substances.
4. Air quality
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 air filters.
Install air filters close to valves at their upstream side. A
filtration degree of 5
μ
m 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 mist separators at the upstream side of valves.
If excessive carbon powder is generated by the compressor,
it may adhere to the inside of the valves and cause
malfunction.
Refer to SMC’s Best Pneumatics catalog for further details on
compressed air quality.
5. Ambient environment
Use within the operable ambient temperature range. Confirm
the compatibility between the product’s composition materials
and the ambient atmosphere. Be certain that the fluid used does
not touch the external surface of the product.
6. Low temperature operation
1) The valve can be used in an ambient temperature of -5
o
C.
However, take measures to prevent freezing or solidification
of impurities, etc.
2) When using valves for water application in cold climates, take
appropriate countermeasures to prevent the water from free-
zing in tubing after cutting the water supply from the pump, by
draining the water, etc. Installation of a dryer, heat retaining of
the body is recommended to prevent a freezing condition in
which the dew point temperature is high and the ambient
temperature is low, and the high flow runs.
7. Do not disassemble the product or make any
modifications, including additional machining.
It may cause human injury and/or an accident.
Mounting
1. If air leakage increases or equipment does not
operated properly, stop operation.
After mounting is completed, confirm that it has been done
correctly by performing a suitable function test.
body only. They can cause the coil to burn out.
2. Secure with brackets, except in the case of
steel piping and copper fittings.
3. Avoid sources of vibration, or adjust the arm
from the body to the minimum length so that
resonance will not occur.
4. Painting and coating
Warnings or specifications printed or labeled on the product
should not be erased, removed or covered up.
VND Series
Valves for Fluid Control
Precautions 1
Be sure to read this before handling.