SMC Networks KR-W2 Series Operation Manual page 9

2. Specific Product Precautions (5)
Connection Thread Tightening Method
Caution
(5)Uni thread fittings
a) First, tighten the threaded portion by hand,
then use a proper wrench, which could be
suitable for the width across flats of the
hexagon body, to tighten it further at a wrench
tightening angle shown below. As a reference
value for the tightening torque, refer to the table
below.
Connection Female Thread: Rc, NPT, NPTF
Wrench tightening
Uni thread
angle after
size
hand-tightening [deg]
1/8 30 to 60
1/4 30 to 60
3/8 15 to 45
1/2 15 to 30
Connection Female Thread: G
Wrench tightening
Uni thread
angle after
size
hand-tightening [deg]
1/8 30 to 45
1/4 15 to 30
3/8 15 to 30
1/2 15 to 30
b) The gasket can be reused up to 6 to 10 times. It can
be replaced easily when it has sustained damage. A
broken gasket can be removed by holding it and then
turning it in the same direction as loosening the
thread. If gasket is difficult to remove, cut it with
nippers, etc. In such a case, use caution not to
scratch the seat face because the seat face of 45
gasket of fitting is the sealing face.
(6)G thread fittings
Tighten fittings with sealant using the proper
tightening torques in the table below.
If tightened using a torque exceeding the proper
torque level, this may cause the fitting to break.
Connection thread size
G1/8
G1/4
G3/8
G1/2
Tightening
torque
[N･m]
3 to 5
8 to 12
14 to 16
20 to 22
Tightening
torque
[N･m]
3 to 4
4 to 5
8 to 9
14 to 15
o
Tightening torque
[N･m]
2 to 4
5 to 7
9 to 11
14 to 16
- 8 -
Tightening tool
Caution
Use a wrench appropriate for the hexagon flats of the
body to tighten the fitting.
Affix the wrench at the base of the thread. If the size
of hexagonal face and wrench do not match, or
tightening takes place near the tube side, it may
cause collapse or deformation of the hexagonal face,
or damage to the equipment.
After installing, confirm that there is no damage to the
fitting, etc.
Recommended
Recommended
NG
NG
NG