8
It is important that a pump should never be subjected to thermal or
pressure shock. The liquid should therefore be allowed to flow into
the casing slowly. A centrifugal pump should never be started until
all the parts are up to the temperature of the liquid to be pumped.
FILLING
WARNING:
Before filling the pump with liquid, check to see that all possible
leak locations are sealed. See that all of the connections into the
pressure containing cavity are sealed or connected to a related
piping system that also has all possible leak paths sealed. Do not
plug unused cavities, as this could develop dangerous pressure
build-up. Use a wrench on all bolted joints to apply torque to assure
that all gaskets are sealed in a tight joint. Check to see that all
threaded pipe connections are also tight enough to seal the Liquid
pressure that will be applied when the system is started.
WARNING:
Filling directions below refer to venting of “air” to the atmosphere,
but dependent upon the physical properties of the liquid intended
to be pumped, temperature, pressure, and other variables related
to the system and its operational requirements, this may not be
allowed by federal or local regulations, or may not be acceptable
for whatever other reasons. Consult your plant or corporate safety
engineer for instruction on possible required procedures for the
specific liquid, operating conditions and legal requirements.
When the source of the liquid to be pumped is below atmospheric
pressure or located below the pump, the filling may be ac -
complished in any of several ways, three of which are listed below:
1) An exhauster may be connected to the discharge piping
between the pump and the discharge isolation valve. With the
discharge isolation valve closed and the suction valve open,
the air can be exhausted from the pump and the suction pip-
ing. When all the air has been removed, close the suction
valve, remove the exhauster, plug the access port where the
exhauster was connected, and then open the discharge valve.
Remove the seal vent plug from the top of the bearing housing,
refer to the drawings on page 6. Allow the air to flow from this
port until the pumpage starts to flow. This could take consider-
able time dependent upon the viscosity of the pumpage.
Fifteen to twenty minutes is not unusual, however some liquids
may vent out in less than a minute. If the pump is a “RA2096”
use a funnel and fill the seal cavity, through this connection
with clean pumpage.
2) With a foot valve installed in the suction piping, the pump may
be filled with pumpage introduced somewhere above the
pump in the discharge piping. A foot valve may create exten-
sive losses and therefore must be allowed for in calculating the
available NPSH. When the pump is filled, plug the port
through which you were filling. Remove the seal vent plug from
the top of the bearing housing, refer to the drawings on page
6. Allow the air to flow from this port until the pumpage starts
to flow. This could take considerable time dependent upon the
viscosity of the pumpage. Fifteen to twenty minutes is not
unusual, however some liquids may vent out in less than a
minute. If the pump is a “RA2096”, use a funnel and fill the
seal cavity, through this connection with clean pumpage.
3) A vacuum pump (preferably a wet vacuum pump) may be
used for evacuating air from the pump and piping. The vacu-
um pump should be connected as is the exhauster covered in
No. 1 above and the procedure is the same.
When the source of the liquid to be pumped is above atmospheric
pressure or above the pumps discharge flange, the pump may be
filled by venting through a bleed-off line to atmosphere. When the
source of the liquid is above the pumps discharge flange the vent-
ing could be back to the suction source, instead of to atmosphere.
When all of the air has been expelled through the bleed-off, seal it.
Remove the seal vent plug from the top of the bearing housing, refer
to the drawings on page 6. Allow the air to flow from this connec-
tion until the pumpage starts to flow. This could take a considerable
amount of time, dependent upon the viscosity of the pumpage.
Fifteen to twenty minutes is not unusual, however some liquids may
vent out in less than a minute. If the pump is a “RA2096”, use a fun-
nel to fill seal cavity, through this connection with clean pumpage.
It is most important to check the direction of rotation of the pump
before allowing the pump to come up to speed. The pump was
shipped with the coupling spacer not installed to allow alignment
and motor rotation direction check. If, however, someone installed
this spacer assembly, remove it at this time. To check rotation direc-
tion, push the starting button and instantly push the stop button. This
will allow the motor to turn over a few revolutions and the direction
of rotation to be observed. A direction of rotation arrow is shown
on the front of the pump casing. If rotation is incorrect, change the
wiring connections and recheck rotation. Operating the pump in
reverse rotation may cause extensive damage.
WARNING:
Lock-out the power to the driver (motor, turbine, engine, etc.) install
the shaft coupling spacer. Be sure that you install all the retaining
devices and bolts and that they are tight. Read and comply with the
coupling manufacturer’s instructions. Personal injury, death, and/or
equipment damage could occur if the coupling spacer is not prop-
erly installed. Remove all debris and tools from the area near the
shafts and the shaft coupling. Do this to assure that nothing is
caught and thrown by the rotating parts when the pump is started.
Bolt the coupling guard securely to the baseplate, checking to
assure that it is not contacting any parts that will rotate when the
pump is started.
OPERATING
WARNING:
Before starting the unit, see that all personnel are a safe distance
away from all possible hazards, that all sub-systems are connected
and operating, that all debris has been removed, that the shaft cou-
pling guard is securely in place, and that the pump is full of
liquid.
Do not operate this pump at shut-off (no flow) as an explosion may
result. This can occur with any liquid, even “cold water”. Personal
injury, death, equipment damage, and/or loss of product
(pumpage) is Likely to occur. If your system is operated where it is
possible for all outlets of the discharge from the pump to be closed
while the pump is still operating, a modification of the system needs
to be made to assure a continual flow of pumpage through the
pump. NOTE: Some people have a belief that a bypass line from the
discharge side of the pump to the suction side of the pump will
relieve this problem, this is “NOT TRUE”; DO NOT ATTEMPT THIS.
WARNING:
Do not operate a pump at a low flow condition, unless provision has
been made to prevent dangerous heat build up within the pump
casing. The liquid in the pump will heat up and this may result in
high pressure in the pump in a short time. Such pressure may result
in a rupture of the pressure-containing parts and cause severe haz-
ard to personnel and/or damage to the system.
STARTING THE PUMP
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