Definition Of Static Pull To Apply On Belts; Transmission Of Power From The Second Pto; Start-Up And Operation; Preliminary Checks - Pratissoli KT-WK Serie Manual De Uso Y Mantenimiento

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.
Values of the static pull to be applied can be obtained from
the diagram in Fig. 11 for belts with a XPB profile in relation to
the wheelbase.
Lf= Wheelbase mm
Conclusion: with a wheelbase of 600 mm and with a
dynamometer, loading the belt branch with 75 N as indicated
in Fig. 12, a "te" bend of approximately 10.8 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 KT HIGH PRESSURE version 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:
4.1 HP at 1450 rpm;
5.0 HP at 1750 rpm.
By means of the joint, withdrawable Max Torque is:
40 Nm which corresponds to:
8.2 HP at 1450 rpm;
10 HP at 1750 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
Fig. 11
(see 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 pressurized
(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 is free discharge, to
permit rapid expulsion of the air present in the pump
manifold and therefore facilitate fast priming.
3. All suction and outlet fittings and connections are
properly tightened.
Fig. 12
31
Fig. 13