SMC Networks SV Series Manual page 4

3/4/5-Port Solenoid Valves
Precautions 4
Be sure to read this before handling products.
Design/Selection
Caution
7. Operation in low temperature conditions
It is possible to operate a valve in extreme temperatures, as
low as –10°C. Take appropriate measures to avoid the
freezing of drainage, moisture, etc., in low temperatures.
8. Operation for air blowing
When using a solenoid valve for air blowing, use an external pilot
type.
Use caution because the pressure drop caused by the air blowing
can have an effect on the internal pilot type valve when internal
pilot type valves and external pilot type valves are used on the
same manifold.
Additionally, when compressed air within the pressure range of the
established specifications is supplied to the external pilot type
valve's port, and a double solenoid valve is used for air blowing, the
solenoids should be energized when air is being blown.
9. Mounting orientation
Rubber seal: Refer to the specifications of each series.
Please consult with SMC for models not indi-
cated in the specification column.
Metal seal: The mounting orientation of a single solenoid is universal.
No specific orientation is necessary. When installing
a double solenoid or a 3-position configuration,
mount the valve so that the spool valve is horizontal.
10. Initial lubrication of main valve
The following initial lubricant has already been applied to the
main valve.
• Rubber seal, spool valve: Grease
Please consult with SMC, as there are some standard
valve products that use fluorine grease for food processing
equipment (NSF H-1).
• Metal seal, spool valve: Turbine oil
Turbine oil is applied to the spool valve of the metal seal type.
Therefore, turbine oil may seep out when a new product is
delivered or while the valve is in storage.
11. For the pilot EXH (PE) port
If the solenoid valve and the manifold's pilot EXH (PE) port is
restricted extremely or blocked, abnormal operation of the
solenoid valve may occur.
Mounting
Warning
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
and inspection.
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 on 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.
Piping
Caution
1. Refer to the Fittings and Tubing Precautions
(pages 52 to 56) for handling One-touch fit-
tings.
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 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.
4. Closed center and double check valve types
For the closed center or double check valve types, check the
piping to prevent air leakage from the piping between the
valve and the cylinder.
5. Connection of piping and fittings
When screwing piping or fittings into the valve, tighten them as
follows.
1) When using SMC's M3, M5, M6, or 10-32UNF fittings,
follow the procedures below to tighten them.
• Connection thread: M3
First, tighten by hand, then use a suitable wrench to tighten
the hexagonal portion of the body an additional 1/4 turn.
The reference value for the tightening torque is 0.4 to 0.5
N·m.
• Connection thread: M5 and 10-32UNF
First, tighten by hand, then use a suitable wrench to tighten
the hexagonal portion of the body an additional 1/6 to 1/4
turn.
The reference value for the tightening torque is 1 to 1.5
N·m.
• M6
First, tighten by hand, then use a suitable wrench to tighten
the hexagonal portion of the body an additional 1/6 to 1/4
turn.
∗ Excessive tightening may damage the thread portion or
deform the gasket and cause air leakage.
Insufficient tightening may loosen the threads or cause
air leakage.
• When using a fitting other than an SMC fitting, follow
the instructions given by the fitting manufacturer.
2) For a fitting with sealant R or NPT, first, tighten it by hand,
then use a suitable wrench to tighten the hexagonal portion
of the body an additional two or three turns. For the tighten-
ing torque, refer to the table below.
Connection thread size (R, NPT)
1 8
1 4
3 8
1 2
3 4
1
1 1 4
1
1 2
2
Winding
direction
Sealant tape
Proper tightening torque (N·m)
3 to 5
8 to 12
15 to 20
20 to 25
28 to 30
36 to 38
40 to 42
48 to 50
48 to 50
6
A