RC, RCV
11
Safety bypass valve: All models have an internal safety valve
which, should the impulsion pressure exceed a calibration
value, recirculates the fluid to aspiration. The danger of the
pump and facility being subjected to excessive pressure is
therefore avoided. The maximum pressure value depends on
each facility, and in consequence this valve should be
regulated as necessary in each case. In order to regulate the
valve, it is important to remember that there is generally a
pressure difference from opening until it is capable of
recirculating all the flow (maximum system pressure).
Depending on the fluid, this margin may be greater than 1.5
Kg. /cm
2
.
Regulate the valve in the following manner:
With the pump shut down, remove the protector cap
(piece 750) and release the turnbuckle (piece 757)
until we see that the spring (756) does not exercise
any pressure or the thread is introduced by at least
two threads, in such a manner as it does not shoot
out when starting up the pump. Replace the protector
cap (750). If this cap is not returned, incoming air
may invalidate the process when starting up the
pump.
If not done already, correctly prime the pump.
If necessary, place a pressure gauge (of suitable
scale) in the pump impulsion.
Start up the pump and proceed to gradually close the
impulsion valve to the full. In this manner the
impulsion gauge will show the pressure necessary to
recirculate all the pumped flow.
Replace the protector cap (750) and gradually tighten
the turnbuckle (757) until the pressure gauge shows
the maximum value permitted in the facility.
Shut down the pump and set the position of the
turnbuckle (757) with the counternut (piece 920.3) or
with the protector cap (piece 750).
If the regulation of the valve is unduly altered, there is
a danger of excess pressure (breakage of pipes
and/or pumps) and/or destruction of the motor
through excess required power. The bypass valve is a
SAFETY valve and should not be used to regulate the flow or
the discharge pressure. Doing this may jeopardise the entire
facility.
6.1.5
Shutdown
Close the discharge pipe valve.
If there is anti-return in impulsion with counterpressure, leave
the impulsion valve open.
-
Shutdown the motor. Check that shutdown is normal.
-
In prolonged periods of non-operation, close the suction
pipe valve and the auxiliary connection valves.
-
In suction pumps using a low vacuum tank, the supply of
liquid must also be maintained at the shaft seal whilst the
pump remains shutdown.
-
The pump must be protected from freezing whenever this
risk exists, and must be emptied in prolonged periods of
non-operation.
If, whilst the pump is shutdown, it must remain on standby for
service, start up at regular intervals for around 5 minutes (see
also
-
Fire pumps: 1x/month, at minimum.
-
Drink-safe water pumps: 1x/48 hours, at minimum.
-
Reserve pumps: 1x/week, at minimum.
(It is best to change the operating pump every day).
The seal tightness and function of the auxiliary connections
must be examined during these start-ups.
6.2
Service limits
6.2.1
Switching frequency
In order to prevent abnormally high temperatures and
overloading of the motor, pump, coupling, seals, etc, the
switching frequencies indicated below must not be exceeded:
MOTOR POWER
MAX. SWITCHING/HOUR
Up to 3 kW
20
From 4 to 11 kW
15
From 11 to 45 kW
10
From 45 kW
5
6.2.2
Temperature of the liquid to be pumped
The permitted operation temperature is indicated in
the datasheet and in the ATEX conformity declaration.
If the pump is to work at a higher temperature or you do not
have the data sheet, please ask KSB ITUR.
6.2.3
Viscosity of the liquid to be pumped
The power absorbed by the pump increases with the
viscosity of the impelled liquid. In order to prevent
overloading in the motor, pump and coupling, this viscosity
must not exceed that shown in the order and in the ATEX
declaration of conformity.
6.2.4
Maximum pump speed
In order to protect the pump from over speed, the maximum
rotation speed shall be that shown on the name plate
engraved in the pump- If the speed shall not be indicated in
the name plate it is necessary to consult with KSB ITUR.
If eventually it would be wished to perform the pump at higher
speed, it is necessary to consult with KSB ITUR.
6.3
Starting up after storage
If the storage and/or shutting down of the pump has been for
a prolonged period of time (over 6 months), it is necessary to:
-
Check the state of the joints.
-
Check the levelling.
-
Check all the auxiliary connections.
-
Renew the lubrication of the bearings (where fitted).
-
Change the gasket (when fitted).
-
After a short storage period, simply turn the pump shaft
manually to unlock the rotor equipment.
-
Follow the specific post-short storage instructions in the
motor manuals and other items.
-
Observe all the steps shown in the "Start-up" section.
If the equipment is to be shutdown for a
certain period of time and there is the
possibility of freezing temperatures, it is necessary to
completely drain the pump in order to prevent any
deterioration from the freezing of the contained fluid.
Note
