Xylem 8100 Series Centrifugal Pumps AC2515 REV.C User Manual
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the anchors and supports are not adequate or
set properly and should be corrected.
STARTING
1. Close drain valves and valve in discharge
line.
2. Open fully all valves in the suction line.
3. Slowly turn on seal water to the stuffing
box. (If pumped fluid is dirty or if leakage
of air is to be prevented, these lines
should be always left open.)
4. Prime the pump.
NOTE: If the pump does not prime properly,
or loses prime during start-up, it should be
shutdown and the condition corrected before
the procedure is repeated.
5. Start the pump driver (turbines and
engines may require warming up; consult
the manufacturer’s instructions).
6. When the pump is operating at full speed,
open the discharge valve slowly. This
should be done promptly after start-up to
prevent damage to pump by operating at
zero flow.
7. Adjust the liquid seal valves to produce
the recommended pressure for either the
mechanical seal or packed stuff box.
OPTIONAL CHECKLIST
1. Driver/Pump Rotation: Check rotation
each time the motor leads have been
disconnected. Be sure that the driver
operates in the direction indicated by the
arrow on the pump casing. Rough
operation and extreme vibration can result
if the pump is operated in the wrong
direction.
2. Flow: An accurate measurement of flow
rate (volume/time) is difficult in the field.
Venturi meters, flow nozzles, orifice
plates, or timing the draw down in the wet
well are all possible methods. Record any
reading for future reference.
3. Pressure: Check and record both suction
and discharge pressure gauge readings
for future reference. Also record voltage,
amperage per phase, kilowatts if an
indicating wattmeter is available, and
pump speed.
4. Temperature: Check and record bearing
temperatures using a thermometer.
Temperature should not exceed 180°F.
5. Vibration and Sound: The acceptable
vibration level of a centrifugal pump
depends on the rigidity of the pump and
the supporting structure. Recommended
values for vibration can vary between .20
ips (inches per second) velocity to .60 ips
velocity depending on the operating
characteristics and the structure. Refer to
the Centrifugal Pump section of the
Hydraulic Institute Standards for a
complete description and charts on
various pumps.
Field sound levels are difficult to measure because
of background noise from piping, valves, drivers,
gears, etc. Follow recommendations in the
Hydraulic Institute Standards.
SHUTDOWN
The following steps will take care of most normal
shutdowns of the pump, i.e. maintenance. Make
any further adjustments of process piping, valves,
etc., as required. If the pump is to be removed
from service for an extended period of time, refer
to the sections on storage and freeze protection.
1. Shut down the driver. (Consult
manufacturer’s instructions for special
operations.)
2. Close suction and discharge valves.
3. Close seal liquid valves. (If pumped liquid
is dirty, or if inleakage is to be prevented,
these lines should always be left open,
except when the pump is completely
drained.)
4. Open drain valves as required.
FREEZE PROTECTION
Pumps that are shut down during freezing
conditions should be protected by one of the
following methods.
1. Drain the pump; remove all liquid from the
casing.
2. Keep fluid moving in the pump and
insulate or heat the pump to prevent
freezing.
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