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Festo 7CRHDb_en
4
Repair steps
4.1
Preparation
•
Before starting the repair, remove any attachments (clamping device, end-position lock, etc.) in accordance with
the instructions in the accompanying operating instructions.
•
Keep your working environment tidy.
•
Only use the spare parts and assembly aids (grease, locking agent, etc.) provided in the set of wearing parts.
Warning
Make sure that the bearing cap cannot suddenly come fl ying off.
•
Remove the non-return valves and tubing connection from the cylinder and depressurise the cylinder completely
so that any pressure present is not suddenly released when the cylinder is opened.
To prevent damage to sealing rims or guide surfaces, do not use pointed or sharp-edged assembly aids.
4.2
Visual inspection
Check the cylinder for visible damage that might impair its function (e.g. warping of the piston rod) as well as deposits
and scoring. The entire cylinder must be replaced if the cylinder barrel is showing signifi cant damage.
4.3
Repairing the cylinder CRHD-…
The description in this chapter can be used to repair cylinders of the type CRHD-… with the following features:
Code Description
Code Description
PPV
Adjustable pneumatic cushioning
MQ
Bearing cap with male thread
A
External position sensing
MC
End cap with clevis
ms
End cap with lug
4.3.1
Structure of the bearing cap
1
4
3
2
5
1
Bearing cap
2
O-ring
3
Cushioning seal
4
Bearing
5
Piston rod seal