VARISCO GS Series, Руководство по эксплуатации и техническому обслуживанию

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Pompa ad ingranaggi - Serie GS, GK
Gear pump - GS, GK Series
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5.4.3 Pump system requirements
In volumetric pumps, pressure is not related to flow rate and/or rotation speed; therefore,
avoid installing shut-off valves on the discharge pipe and, in any case, if not incorporated
with the pump, a relief valve must always be installed between the pump and the stop valve.
5.4.4 Startup/shutdown frequency
Pumps which are expressly requested by the Customer to start frequently and repeatedly do
not show any problems for this kind of operation.
5.4.5 Operation and startup with closed valve
It is forbidden to start the pump with the discharge valve closed: such mistake would
cause an abrupt pressure rise above the limit values with consequent seizing.
5.5 SHUTDOWN
5.5.1 Decommissioning
In case of decommissioning of the pump unit, it is necessary to disconnect the power supply
to make unexpected and accidental startups impossible.
5.5.2 Emptying
A pump or a pump unit which operates with a flammable, toxic, corrosive or, in any way,
hazardous fluid, or with a liquid at a temperature higher than 55 °C, shall be equipped with a
device such as a connection pipe, to be provided by the User, to collect and dispose the
liquid drained or coming from any possible leakage from the shaft seal or discharged by a
pressure relief valve.
6. MAINTENANCE AND INSPECTION
Maintenance operations and pump disassembly must be performed only by author-
ized and specifically trained people.
People with pacemakers must stand at least 2 meters far from magnetic couplings or
from pumps with such couplings. It is a Customer’s responsibility to keep an eye that
this disposal is observed by all people working on pumps or near the pumps.
6.1 USE PRECAUTIONS
Before performing any maintenance operation, please observe the following safety precau-
tions:
- Never execute maintenance operations with the pump running.
- Cut the power supply to the pump unit.
- Wear gloves, glasses, shoes and protective suits adequate to the characteristics of the
liquid being pumped.
- Wait until the pump is cooled.
- Never open the pump unit and/or the relief valve when the pump is pressurized.
- Close suction and discharge pipe valves, if any.
- Disconnect the pump from suction and discharge pipes, by paying attention to put a col-
lecting basin for the pipe liquid.