Datasheet
1. During installation, secure the rod cover and tighten 
by applying an appropriate tightening force to the 
retaining nut or to the rod cover body.
If the head cover is secured or the head cover is tightened, the 
cover could rotate, leading to the deviation.
2. Tighten the retaining screws to an appropriate 
tightening torque within the range given below.
ø10: 5.9 to 6.4 N·m, ø16: 10.8 to 11.8 N·m
3. To remove and install the retaining ring for the 
knuckle pin or the clevis pin, use an appropriate 
pair of pliers (tool for installing a type C retaining 
ring). In particular, use a pair of ultra-mini pliers for 
removing and installing the retaining ring on the 
ø10 cylinder.
4. In the case of auto switch rail mounting type, do not 
remove the rail that is mounted. Because retaining 
screws extend into the cylinder, this could lead to 
an air leak.
5. Please contact SMC when the stroke exceeds 100 
mm for the axial foot mounting style.
<Precautions on the single acting cylinder>
1) Do not operate it in such a way that a load would be applied during 
the retraction of the piston rod of the spring return style, or during 
the extension of the piston rod of the spring extend style. The 
spring that is built into the cylinder provides only enough force to 
retract the piton rod. Thus, if a load is applied, the piston rod will 
not be able to retract to the end of the stroke.
2) A breather hole is provided in the cover surface. Make sure not to 
block this hole during installation, as this could lead to a 
malfunction.
<Precautions on the non-rotating cylinder>
1) Tighten the retaining screws to an appropriate tightening torque 
within the range given below.
ø10: 10.8 to 11.8 N·m, ø16: 20 to 21 N·m
2) Do not operate it in such a way that rotational torque would be 
applied to the piston rod. If rotational torque is applied, the non-
rotating guide will become deformed, thus affecting the non-
rotating accuracy.
Allowable rotational torque (N·m)
ø10 ø16
0.02 0.04
3) To screw a bracket onto the threaded portion at the tip of the piston 
rod, make sure to retract the piston rod entirely, and place a 
wrench over the fl at portion of the rod that protrudes. To tighten, 
take precautions to prevent the tightening torque from being 
applied to the non-rotating guide.
Caution
Be sure to read before handling. Refer to back cover for Safety Instructions. For Actuator 
and Auto Switch Precautions, refer to “Handling Precaution for SMC Products” and the 
Operation Manual on SMC website, http://www.smcworld.com
Series CJ2
Specifi c Product Precautions
1. Use within the specifi ed cylinder speed and kinetic 
energy ranges.
Otherwise, cylinder and seal damage may occur.
2. Do not apply excessive lateral load to the piston 
rod.
Easy checking method
Minimum operating pressure after the cylinder is mounted to 
the equipment (MPa) = Minimum operating pressure of 
cylinder (MPa) + {Load weight (kg) x Friction coefficient of 
guide/Sectional area of cylinder (mm
2
)}
If smooth operation is confi rmed within the above value, the 
load on the cylinder is the resistance of the thrust only and it 
can be judged as having no lateral load.
Warning
Mounting
96
CJ2CJ2WCJ2CJ2KCJ2KCJ2ZCJ2ZWCJ2RCJ2RCJ2RKCJ2RK
StandardBuilt-in Speed ControllerDirect Mount
Double Acting, Single Rod
Double Acting, Double Rod
Single Acting, Spring Return/Extend
Double Acting, Single Rod
Single Acting, Spring Return/Extend
Double Acting, Single Rod
Double Acting, Double Rod
Double Acting, Single Rod
Single Acting, Spring Return/Extend
Double Acting, Single Rod
Auto Switch
Made to Order
Single Acting, Spring Return/Extend
Non-rotating RodDirect Mount, Non-rotating Rod










