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On the variator
Always check the oil level before putting the agitator into operation. Variators are supplied without oil;
in this caseseeto the lling with the issuedoil until reachingthe maximum level visible from the special
indicator.
Sometypes of variators are supplied with un-drilled capsand are supplied with a vent plug, which must
be replacedwhen installing at the place of the cap,situated in the highest position, in order to avoid leaks
of lubricant causedby the variation of the general internal pressureduring the operation. The Variators
supplied with permanentlubricant with lifelong greaselack the load, level anddrain plugs.
- Continuous speed variator is achievedby turning hand wheel.
N.B.: the motovariator must berunning before the adjustment canbe made.
On the impeller
Do not start the agitator if the impeller is immersed in silt, unless this method of operation has been
conditioned in the design phase.
On the entire unit
Check the tightening of all the bolts and nuts. (repeatthe operation after two weeksof operation).
After having carried out above-mentionedinspections, you may proceed with starting the agitator with
the pre-arrangedcontrol devices.
At the beginning of the operation, just as any machine running in, an agitator – causedby the greater
friction’s – can lead to overheating and a higher absorption of current of the motor; these problems
gradually disappearduring the operation.
When a gearbox – cycle converter – is installed, it is generally advisable in time to gradually increasethe
transmitted power, starting from the minimum values,or limiting it (50-70% of the maximum power) for
the rst hours of the operation.
Should an excessive unforeseen absorption occur, disconnect the motor from the power grid, check the
perfect eciency of the contact of the connectionsand check that the working conditions correspondto
those established, especially with regard to the density and viscosity of the liquid; in casethe overload
persists, contact our technical department.
If there are vibrations, stop the agitator immediately and determine the causesthat provoke it.
All the agitators aresuitable for the operation with a maximum and constantlevel; if not foreseenin the
testingphase,avoid the operation in tanks at variable or insucient levels.
On the seals
- Packing type: tighten the stung box before putting the tank under pressure.In caseof lateral
agitators, where the sealis under the level of the liquid, an initial dripping is considered normal,
which thenmust bedeletedby adjusting the tightening of the stufng box.
Single mechanical type: it is not necessaryto carry out any preliminary operation since the seal
is already readyfor duty after the installation on the control unit of the agitator.
Check if the seal model is suitable for rotating in one or both rotation directions. In case of
lateral agitators where the seal is under the level of the liquid, make sure that it is always in
contactwith the liquid. Take carethat in the operationsof emptying following lling of the tank
zonesof accumulated air (air bubbles) around the seal are not created.
Even a few secondsof running dry can create localised overheating, which seriously damages
the mechanical seal. The damagesderiving from having run dry are easily recognisable the seal
shows evident signs of burning and the counter face (if in aluminium) may be cracked due to
thermal shock. The failures causedby running dry are never repaired under the guarantee.
- Double mechanical type: must be usedwith a coolant; this liquid must circulate in the housing
of the seals before starting the agitator. The liquid in circulation between the seals must
generally be maintained at a pressure exceeding 1 Atm of that in the vessel. If the pressure of
the coolant doesnot exceed 2 Atm, the external sealcan be carried out with oil sealring.
