18
GB
6. Maintenance
6.1 Cleaning
The pump must be emptied, flushed and if necessary cleaned
after pumping adhesive, crystallizing or contaminated liquids
especially before longer downtimes. Function of mechanical
seal and joint seals must be controlled.
Proceed as follows:
• Close the pump discharge and the circulation pipeline by
means of a valve.
• The B70V-HD-D pump can be emptied by changing the
direction of rotation.
• Position the pump into a container with cleaning agent.
• Open the circulation line.
• Start the pump with the direction of rotation necessary
for operation and let the cleaning agent circulate
(Fig. 9)
.
These steps are sufficient to guarantee operational reliability
of the pump. If the pump shall be used for another liquid, we
recommend to open and to clean the pump as follows:
• Remove the wing nut above the pump discharge
(Fig. 10 – Item 1)
.
• Remove the pump tube downwards until the mechanical seal
is accessible
(Fig. 10 – Item 2)
.
• Any residues of the liquid being pumped now can be
removed.
• Inspect the mechanical seal
(Fig. 10 – Item 2)
and the hinge
seals
(Fig. 10 – Item 3)
for damage and leak tightness (e.g.
broken parts, cracks or grooves).
• The pump now can be reassembled for further use.
6.2 Lubrication
No parts of the Lutz eccentric screw pump need be lubricated
at short intervals. The flanged-on drive units should be serviced
as follows:
B70V-HD-D
The rolling bearings of the motor and the pump should be
replaced after 8000 hours or 2 years of operation.
B70V-HD-SR
Planetary gears
Refer to the operating instructions for the gear.
Universal motors
Refer to the operating instructions for the motor.
Compressed air motors
Refer to the operating instructions for the motor
6.3 Changing the stator
Only use PTFE stators and stator sleeves marked
with PTB-No. for flammable liquids.
Stator and rotor are wear parts. Their service life largely
depends on the prevailing conditions.
• The residual liquid in the pump tube must be emptied through
the outrun piece before disassembly.
• Release the clamp screw at the stator sleeve for
disassembly.
• Release and remove the pump foot.
• Force the stator out of the pump foot (stator sleeve).
• Soiled threads on the pump tube and the stator sleeve must
be cleaned and lightly lubricated.
• For assembly insert the first thrust ring into the stator
sleeve.
• Press the new stator into the stator sleeve.
• Put the second thrust ring onto the stator. Note the nose
and notch on the sleeve and stator when replacing solid
stators.
• Screw the stator sleeve onto the pump tube.
• Fasten the stator sleeve hand-tight and clamp with the clamp
screw.
