Festo CRDNG Series, Repair Instructions, Page: 13 / 26

13 / 26 Festo 7CRDNGb_en
4.3.3 Replacing the piston components
• Pull the piston rod out of the cylinder barrel.
• Check the cylinder barrel and piston rod for damage.
The entire cylinder must be replaced if the cylinder barrel (particularly the
bearing surface) is showing significant damage.
• Unscrew the threaded coupling (the rear part of the piston rod on cylinders
with through piston rod (S2)) from the piston rod.
• Remove the piston components from the piston rod, noting the order and
orientation.
• Remove any residue of the screw locking agent from the threads of
the piston rod and threaded coupling (the thread on the rear part of
the piston rod on cylinders with through piston rod (S2 )).
• Replace the components with those included in the set of wearing parts and
reassemble the piston components on the piston rod in the correct order.
• Apply the screw locking agent included in the set of wearing parts to
the inside of the threaded coupling (the rear part of the piston rod on
cylinders with through piston rod (S2)) and screw it onto the piston rod with
the corresponding torque (see table).
Type Torque
CRDNG(S)-32 / CRDNG-32-…-S2 10 Nm
CRDNG(S)-40 / CRDNG-40-…-S2 20 Nm
CRDNG(S)-50 / CRDNG-50-…-S2 30 Nm
CRDNG(S)-63 / CRDNG-63-…-S2 30 Nm
CRDNG(S)-80 / CRDNG-80-…-S2 40 Nm
CRDNG(S)-100 / CRDNG-100-…-S2 60 Nm
CRDNG(S)-125 / CRDNG-125-…-S2 160 Nm
4.3.4 Inserting the piston rod into the cylinder barrel
• Clean the inner surface of the cylinder barrel as described in
chapter
5.1 "Cleaning" .
• Apply the grease included in the set of wearing parts to the following parts:
Component Greasing
Inner surface of cylinder barrel Thin film
1)
Surface of piston rod Thin film
1)
Piston seal lip rings Thin film
1)
on
outside
Piston surface between lip rings
(grease reservoir
2)
)
Fill 2/3 with grease
Cushioning boss Thin film
1)
on
outside
1)
See chapter 5.2.2 "Thin grease film"
2) See chapter 5.2.3 "Grease reservoir"