Lenntech Danfoss PAHF Series User manual

521B1121 DKCFN.PI.011.D1.02 11-2009
INSTRUCTION
Servicing PAHF 20-40
180R9180 180R9180
DISASSEMBLY
1. Tools required for dismantling PAHF 20-40
2. Loosen and remove 6 screws
3. Remove mounting ange
4. Remove O-ring
5. Remove 2 guide pins
6. Remove shaft sealing
7. Remove spring
NOTE: Disassembly of the pump within the warranty period
will void the warranty.
Lenntech
[e-mail] Tel. [phone]
www.lenntech.com Fax. [phone]
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www.lenntech.com Fax. [phone]
Lenntech

2 DKCFN.PI.012.D1.02 521B1121
12. Remove cover
13. Remove pin
14. Remove pistons and retainer plate
15. Remove retainer ball
8. Remove washer for shaft seal
9. Loosen ange (2 screws). Don’t remove yet.
10. Turn pump upside down
11. Loosen and remove 8 screws

521B1121 DKCFN.PI.012.D1.02 3
20. Remove pump housing from rest of the pump
21. Raise pump to vertical position and remove 1 guide pin
22. Remove cylinder barrel
23. Remove valve plate
16. Remove bush
17. Remove spring
18. Place pump horizontally
19. Remove 2 screws

4 DKCFN.PI.012.D1.02 521B1121
24. Remove 1 guide pin
25. Remove O-ring from port ange
26. Loosen thrust plate from cylinder barrel
27. Remove thrust plate
28. Remove O-rings from thrust plate
29. Remove back-up rings from thrust plate
30. Remove O-ring from end cover plate

521B1121 DKCFN.PI.012.D1.02 5
31. Remove shaft sealing from mounting ange
32.
33. Pump disassembled

6 DKCFN.PI.012.D1.02 521B1121
INSPECTION:
Valve and thrust plate
1. Neither valve plate nor thrust plate must show any sign of wear.
2. Hold a ruler against surface of plate and check tightness against a
light source.
3. Check that both O-rings and back-up rings are not broken and do
not show severe wear.
Swash plate:
1. Check that surface of swash plate is smooth and without any large
scratches (depth more than 0.1 mm).
Bearings
1. Check bearing in swash plate for wear and scratches
2. Check bearing in port ange for wear and scratches
Retainer cone:
1. Check the retainer cone for scratches

521B1121 DKCFN.PI.012.D1.02 7
Pistons
1. Clearance in ball and socket joint must not exceed 0.1 mm.
2. Thickness of piston shoes must be at least 4.1 mm.
3. Hold a ruler against surfaces of piston shoes to check that the
surfaces are even and smooth and without any scratches.
4. Check bushes in cylinder barrel for wear and scratches

8 DKCFN.PI.012.D1.02 521B1121
5. Place the port ange on a support (eg. a coupling housing)
6. Mount valve plate. Be aware of orientation/guide pin
7. Mount back-up rings on thrust plate
8. Mount O-rings on thrust plate
ASSEMBLY
1. Tools required for assembly of PAHF 20-40
2. Parts needed for assembly of PAHF 20-40
3. Mount O-ring in port ange
4. Mount 1 guide pin in port ange

521B1121 DKCFN.PI.012.D1.02 9
9. Spray water on cylinder barrel and thrust plate
10. Mount thrust plate on cylinder barrel
11. Press thrust plate into cylinder barrel
12. Spray water on valve plate
13. Mount cylinder in ange
14. Mount pump housing
15. Mount 2 x screws in the bottom
16. Tighten with tool

10 DKCFN.PI.012.D1.02 521B1121
17. Mount spring
18. Mount bushing
19. Mount retainer ball on top of the spring
20. Spray with water
21. Take out 2 pistons as showed
22. Mount pistons in housing
23. Mount the 2 last pistons
24. Mount 1 guide pin in pump housing