Lutz B70V, Translation Of The Original Instructions

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20
GB
4.6 Mechanical loads on the pump tube
The pump tube’s functioning and service life are impaired
when deformed by mechanical loads. For this reason, the
outlet must not be subjected to compressive or tensile forces
(see Fig. 5)
.
The bending moment M
B
at the outlet must not exceed 50
Nm.
4.7 Maximum immersion depth
Care must be taken to ensure that the pump is not submerged
further than its discharge port
(see Fig. 6)
.
5. Operation
5.1 Dry running
The pump is said to run dry if it continues to operate without
pumping any liquid whatsoever. Dry running must be avoided
(see Fig. 7)
. This can be ensured by remaining in attendance or
with the aid of such technical means as a flow monitor, etc.
5.2 Suction funnel
At least the intake port must be completely covered with me-
dium in order to prevent the infiltration of air while pumping.
When pumping highly viscous products, care must also be
taken to prevent the formation of suction funnels.
5.3 Operation with closed discharge
The eccentric screw pump B70V/B70V-SR is a positive
displacement pump and must not be operated with
closed shutoff elements, such as the nozzle, valves, etc.
for the excessive pressure build-up may result in dam-
age.
Following max. pressure must not be exceeded:
Pump tube B70V
12.1
B70V
25.1
B70V
25.2
B70V
50.1
B70V
75.1
Max. pressure 6 bar 8 bar 10 bar 8 bar 8 bar
The use of a bypass valve with return line is strongly recom-
mended. The maximum pressure is then limited by the bypass
valve.
6. Maintenance
6.1 Cleaning
It is advisable to empty, flush and clean the pump tube after
pumping aggressive, tacky, crystallizing or contaminated liq-
uids. The pump must be switched off and repaired immediately
if liquid leaks out below the pump motor
(see Fig. 8)
.
(Packing gland: retighten or replace packing; mechanical seal:
repair or replace.)

Small amounts of liquid leak from the packing glands
in particular; this liquid is required to lubricate the
packing.
6.2 Mechanical seal
The single-action mechanical seal is dependent on the direction
of rotation and must therefore never be operated in the direction
opposite to that indicated by the manufacturer’s arrow.
Single-action mechanical seals do not normally require any ad-
ditional parts and need only be inspected and possibly replaced
if major leaks occur.
6.3 Packing gland
If the liquid being pumped emerges through the openings in the
lantern, the round nut with holes in the packing gland must be
adjusted by turning clockwise with the aid of a round pin.