SMC Networks KF Series Operation Manual page 8

2. Specific Product Precautions (4)
Maintenance
Warning
(1) Perform maintenance inspections according to the
procedures indicated in the operation manual.
If handled improperly, malfunction and damage of
machinery of equipment may occur.
(2) Maintenance work
If handled improperly, compressed air can be
dangerous. The 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
When 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 the equipment is restarted, proceed with
caution after confirming that appropriate measures
are in place to prevent cylinders from sudden
movement.
Caution
(1) Be certain to wear safety glasses at all times during
periodical inspections.
(2) During regular maintenance, check for the following
and replace any components as necessary.
a) Scratches, gouges, abrasion, corrosion
b) Leakage
c) Flattening or distortion of tubing
d) Hardening, deterioration or softness of tubing
(3) Do not repair the fittings or patch the tubing for
reuse.
(4) Using this product for extended periods of time
can result in leaks due to the material change. In
such cases, tighten the union nut additionally.
A guide for the additional tightening is 1/6 to 1/4
turns. But in case of the brass sleeve, the limit for
additional tightening is 1/2 turns.
When there is a leak even after additional
tightening, replace the sleeve with new one.
(5) Sleeve is not recyclable. Replace it every time
piping is performed.
Connection Thread Tightening Method
(1)
Fittings with sealant: R
1) First, tighten the fitting by hand, then use a
wrench appropriate for the hexagon flats of the
body to tighten it a further two or three turns. For a
tightening torque guide, see the table below.
Connection thread size
R1/8
R1/4
R3/8
R1/2
2) If the fitting is tightened with excessive torque, a
large amount of sealant will seep out. Remove the
excess sealant.
3) Insufficient tightening may cause seal failure, or
loosen the threads.
4) 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.
8
Tightening torque [N・m]
3 to 5
8 to 12
15 to 20
20 to 25