Festo DZF - Repairing the Bearing and End Caps

15 / 24Festo 7DZF / DZHb_en
• Push the piston far enough into the cylinder barrel so that the  rst piston
seal protrudes slightly at the other end of the cylinder barrel.
• Pull the piston rod back again until the piston is sitting fully in the cylinder
barrel.
Note
This approach ensures that the lips of the two piston seals sit correctly in the
cylinder barrel.
4.3.5 Repairing the bearing and end caps
• Remove the seal 3 from the slot of the bearing cap 2 and end cap
(the rear bearing cap on cylinders with through piston rod (S2 / S20)).
• Remove the piston rod seal 1 from the bearing cap 2 (the front and
rear bearing caps on cylinders with through piston rod (S2 / S20)).
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Warning
Check the plain bearing in the bearing cap (the front and rear bearing caps
on cylinders with through piston rod (S2 / S20)) for visible damage that
might impair its function, such as deposits and scoring. The entire bearing
cap must be replaced if the plain bearing is showing signi cant damage.
• Clean the seat of the piston rod seal 1 and seal 2.
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• Grease the new piston rod seal (one per bearing cap on cylinders with
through piston rod (S2 / S20)) as follows:
Component Greasing
1 Grease reservoir
2)
for piston rod Fill 2/3 with grease
2 External surface for bearing cap Thin  lm
1)
3 Grease reservoir
2)
for bearing Fill 2/3 with grease
1)
See chapter 5.2.2 "Thin grease  lm"
2)
See chapter 5.2.3 "Grease reservoir"
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