Definition Of Static Pull To Apply On Belts; Transmission Of Power From The Second Pto; Start-Up And Operation; Preliminary Checks - Interpump Group SS70 Série Manuel D'utilisation Et D'entretien

9.12

Definition of static pull to apply on belts

Static pull depends on:
a) The wheelbase between the two pulleys (belt length).
b) The load due to static pull of the belt.
c) The number of belts.
d) The winding angle of the smallest pulley.
e) Average speed.
f ) Etc.
The diagram in Fig. 11 for belts with an XPB profile in relation
to the wheelbase indicates the correct tensioning Tc (belt sag
with a dynamometer load of 71 N).
Lf= Wheelbase mm
Conclusion: with a wheelbase of 400 mm and with a
dynamometer, loading the belt branch with 75 N as indicated
in Fig. 12, a "te" bend of approximately 8.4 mm is obtained.
Lf = Wheelbase
te = Belt bend
Fe = 75 N Dynamometer load
Note . Unless otherwise stated by the supplier of the belts,
1
control of proper pull and its relative re-tensioning should be
performed after no less than 30 minutes of motion necessary
for the normal adjustment of the belts. Best performance and
durability will be achieved with proper tensioning.
Note . In case of necessity or for routine maintenance, never
2
replace a single belt but the complete set.
9.13

Transmission of power from the second PTO

Upon request, the SS70 and SN70 series pumps can be
supplied with auxiliary PTO on the side opposite of the drive
(Transmission of power from the second PTO).
Transmission can be carried out:
• By means of the V-belts.
• By means of the joint.
By means of the V-Belts, withdrawable Max Torque is:
20 Nm which corresponds to:
2.3 HP at 800 rpm;
4.1 HP at 1450 rpm.
By means of the joint, withdrawable Max Torque is:
40 Nm which corresponds to:
4.6 HP at 800 rpm;
8.2 HP at 1450 rpm.
By means of the V-belt, the transmission is considered
suitable if: belt pull is applied at a max distance
of 18 mm with from the bend shaft shoulder (see
Fig. 11
Fig. 13). Min diameter of pulley to be used = Ø
100 mm.
With transmission by means of the joint, pay
particular attention to perfect alignment so that no
transverse forces are generated on the pump shaft.
For applications differing from those specified
above, contact our Technical or Customer Service
Departments.
10

START-UP AND OPERATION

10.1

Preliminary checks

Before start-up, ensure that:
The suction line is connected and pressurised
(see par. 9.4 - 9.5 - 9.6) the pump must never run
dry.
1. The suction line ensures a hermetic seal over time.
2. Any shut-off valves between the supply source and
the pump are fully open. The outlet line during is free
discharge, to permit air present in the pump head to come
out quickly and therefore favour fast priming.
3. All suction and outlet fittings and connections are
properly tightened.
Fig. 12
4. The coupling tolerances on the pump/transmission axis
(half-joint misalignment, Cardan joint tilt, belt pulling,
etc.) remain within limits required by the transmission
manufacturer.
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Fig. 13