48
Fixing torque [Nm] for screws A2/A4
(Coefficient of friction = 0,2)
A2/A4,
Hardeness class 70
A2/A4,
Hardeness class 80
DIN912/DIN933
DIN912/DIN933
M6
7 Nm
11,8 Nm
M8
17 Nm
28,7 Nm
M10
33 Nm
58 Nm
M12
57 Nm
100 Nm
M16
140 Nm
245 Nm
M20
273 Nm
494 Nm
6.2. Maintenance
It is imperative to keep a maintenance list to be always informed about the submersible mixer. This list must be
presented to the trade association, the technical inspection agencies and the manufacturer of the system or of the
mixer when requested.
The full warranty requires the annual inspection of the mixer by the manufacturer of the system or of the mixer.
6.2.1. General (Monthly or every 500 operating hours)
Clean the mixer from all attached solids. Check the motor cable for damages. In case of any damages of cable
surface replace cable through mixer manufacturer or authorized repairshop.
Check mixer painting and surface for scratches or damages. Repaint surface or replace damaged parts.
6.2.2. Electric Motor
The current consumption must be checked for all 3 phases monthly. Damages of the motor, transmission and
bearing can be detected via the power consumption.
Lubrication: The bearings are lubricated for life (when noises arise, bearings must be replaced at the manu-
facturer's works).
The oil in the oil chamber should be changed after every 6000 hours of operation.
Oil condition: Place mixer horizontally so that one of the oil chamber screws is at the top. Remove the screw and
extract a small amount of oil. If the oil is milky or cloudy, it indicates a defective shaft seal. In this case, have the
condition of the shaft seals checked by HOMA-workshop or factory service.
Replace shortages
Isolation test: If the insulation resistance is less than 2 megohms, do not turn the submersible mixer on. (Mea-
suring DC voltage 1500 Volts).
6.2.3. Stirring Propeller
Inspection: Inspect the stirring propeller periodically. Remove random wound foreign bodies such as twines,
cords, etc. They can cause uneven running and thus create strong vibrations in the system and can lead to
damage on the mixer components. With uneven running, the stirring propeller must be cleaned.
6.3. Change of oil
Change oil only with motor at operation temperature. Note that the mixer must be in a horizontal
position when changing oil.
When releasing the oil level screws, excess pressure may escape from the oil chamber or the gearbox. Only
remove the screws completely after the pressure was equalized.
The thread and the magnets (on the gearbox) of the screws must be clean before screwing them back on.
The sealing rings must be always replaced with new parts.