11. Maintenance
These dosing pumps are produced to the highest quality standards, and have a long service life. Neverthe-
less some parts are subject to wear caused by operation (e.g. piston, valve seats, valve balls). Regular
visual inspections are therefore necessary in order to ensure a long operating life. Regular maintenance will
protect the dosing pump from operation interruptions. The manufacturer recommends maintenance once
per year, provided the local regulations do not specify more frequent maintenance.
11.1 Lubrication
The piston dosing pump FEDOS E/DX requires little maintenance. The dosing pump gear is lubricated
with gear oil of viscosity class ISO-VG460 according to DIN 51519 (corresponds to SAE 140 according to
DIN 51512). The initial filling supplied must be replaced after about 500 operating hours. Subsequent oil
changes should be carried out every 5,000 operating hours. The filling capacity is about 0.25 l for gears.
The actually quantity of gear oil required can be determined by checking the min.-max. markings of the
oil-measuring stick.
ATTENTION!
FEDOS DX: To avoid damaging the proximity switch inside the gear housing, the dosing pump must be
switched off before removing the oil dipstick.
11.2 Maintenance of the bearings
The upper bearing of the pinion shaft is a sealed and permanently lubricated ball bearing. The other rolling
bearings in the gearing, and the plain bearings of the diaphragm rod, are lubricated by the gear oil. The oil
also performs a heat dissipation function.
All bearings must be examined for wear after 5000 hours of operation. The service life of the rolling bear-
ings depends on the applied loads. If the dosing pump is operated at maximum load, bearings must be
replaced after 5,000 hours of operation.
11.3 Maintenance of the ATE servomotor (optional)
The ATE servomotor comes with lifetime lubrication ex factory. Nevertheless, regular inspections are recom-
mended if the drive is operated in tough operating conditions, for example in high ambient temperatures
or continuous operation. To re-lubricate the ATE gear, use molybdenum disulphite, for example "Molykote
BR2plus" or "OKS400".
11.4 Replacing the piston
CAUTION!
Chemical may spray out. This may lead to chemical or other burns. The dosing pump must always be
depressurised and rinsed with water or a suitable medium before starting any work on the dosing pump.
a
Dosing head with discharge and suction
valve
b
Support ring
c
Supporting disk
d
Packing rings
e
Gland
f
Gland connection
g
Piston
Fig. 11.1: Dosing head FEDOS E/DX
1
7
2
3
4
3
5
6
Maintenance | Operating Manual FEDOS E/DX |
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