Danfoss APP 1.0 Installation, Operation And Maintenance Manual page 45

Instruction
3. Appendix 1
Recommended service intervals for APP pumps
Pistons:
The pistons are the heart of the pump regarding
service.
If the pistons break down, the pump will suffer a
breakdown.
Cavitation of the piston shoes.
New inspection is required in 3,000-4,000 hours.
Cavitation of the piston shoes.
All pistons must be replaced within the next
100-200 hours.
Abrasive wear of the piston shoes.
All pistons must be replaced immediately.
180R9262 / IOM APP 0.6-1.0 Appendices - v02 / 12.2012
In case of doubt - the pistons must be replaced.
The pictures below is ment as a guideline for
evaluating the wear of the sliding surface.
Cavitation of the piston shoes.
All pistons must be replaced within the next
500-1,000 hours.
Cavitation of the piston shoes.
All pistons must be replaced immediately.
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