SM-P00077-A/3
2. INSTALLATION
38
2020-04-15
◼
Spatter
In an environment exposed to spatter, use flame-retardant tubes or steel pipes.
◼
Hydraulic hose
When piping is for use in both hydraulic and pneumatic systems, use a hydraulic hose.
When the standard push-in fitting is used with a spiral tube, secure the base or end of the tube with a
hose clamp. Otherwise, the tube will rotate and lose its clamping ability.
In an atmosphere where the temperature is high, use fastening fittings, not push-in fittings.
◼
Commercially available tubes
When using commercially available tubes, check the outside diameter accuracy, wall thickness, and
hardness of such tubes. The hardness of a urethane tube should be 93° or more (as measured by a
rubber hardness meter).
Using a tube with insufficient diameter accuracy and hardness will cause the chucking force to drop,
which makes the tube come off easily or difficult to insert.
Tube dimensions
Outside
diameter (mm)
Inside diameter (mm)
Nylon
Urethane
ø1.8
-
ø1.2
ø4
ø2.5
ø2
ø6
ø4
ø4
ø8
ø5.7
ø5
ø10
ø7.2
ø6.5
◼
Minimum allowable bending radius of tubes
Observe the minimum allowable bending radius of tubes. Neglecting the minimum allowable bending
radius may cause disconnection or leakage.
Outside
diameter (mm)
Minimum allowable bending
radius (mm)
Nylon
Urethane
ø1.8
-
4
ø4
10
10
ø6
20
20
ø8
30
30
ø10
40
40
◼
Tube cutting
To cut a tube, use a tube cutter to cut the tube perpendicularly to the length of the tube. Inserting an
obliquely cut end of a tube may cause air leakage.
◼
Tube connections
From the end of the fitting, secure a straight section as long as the outside diameter of the tube and do
not bend the tube abruptly at the fitting connection point. The tension applied sideways through the tube
should not exceed 40 N (or 5 N for C18, CL18, and CLL18).
◼
Blanking plug to use
For solenoid valves provided with push-in fitting, use blanking plugs specified by CKD:
• Blanking plug (PG-P2-B)
: ø1.8 push-in fitting
• Blanking plug (GWP
□
-
B Series) : ø4 to ø10 push-in fitting
Outside diameter tolerance
Soft or hard nylon
± 0.1 mm
Urethane ø1.8
± 0.1 mm
Urethane ø4, ø6
+0.1 mm
-0.15 mm
Urethane ø8, ø10
+0.1 mm
-0.2 mm
