Maintenance of flood damaged pumps, Lubrication – Goulds Pumps 3409 - IOM User Manual

Page 32

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clean industrial solvent and replace the grease with the proper
type as recommended.

EVERY 6 MONTHS

Check the packing and replace if necessary. Use the grade
recommended. Be sure the seal cages are centered in the
stuffing box at the entrance of the stuffing box piping
connection.

Take vibration readings on the bearing housings. Compare the
readings with the last set of readings to check for possible
pump component failure (e.g. bearings).

Check shaft or shaft sleeve for scoring. Scoring accelerates
packing wear.

Check alignment of pump and driver. Shim up units if
necessary. If misalignment reoccurs frequently, inspect the
entire piping system. Unbolt piping at suction and discharge
flanges to see if it springs away, thereby indicating strain on
the casing. Inspect all piping supports for soundness and
effective support of load. Correct as necessary.

EVERY YEAR

Remove the upper half of the casing. Inspect the pump
thoroughly for wear, and order replacement parts if
necessary.

Check wear ring clearances. Replace when clearances
become three (3) times their normal clearance or when a
significant decrease in discharge pressure for the same flow
rate is observed.

See Engineering Data Section in the Appendix for standard
clearances.

Remove any deposit or scaling. Clean out stuffing box
piping.

Measure total dynamic suction and discharge head as a test of
pump performance and pipe condition. Record the figures and
compare them with the figures of the last test. This is important,
especially where the fluid being pumped tends to form a deposit
on internal surfaces. Inspect foot valves and check valves,
especially the check valve which safeguards against water
hammer when the pump stops. A faulty foot or check valve will
reflect also in poor performance of the pump while in operation.

NOTE: The above timetable is based on the assumption that
after startup, the unit has been constantly monitored and
such a schedule was found to be consistent with operation, as
shown by stable readings. Extreme or unusual applications
or conditions should be taken into consideration when
establishing the maintenance intervals.

MAINTENANCE OF FLOOD DAMAGED PUMPS

The servicing of centrifugal pumps after a flooded
condition is a comparatively simple matter under normal
conditions.

Bearings are a primary concern on pumping units. First,
dismantle the frame, clean and inspect the bearings for any
rusted or badly worn surfaces. If bearings are free from rust
and wear, reassemble and relubricate them with one of the
recommended lubricants. Depending on the length of time
the pump has remained in the flooded area, it is unlikely
that bearing replacement is necessary; however, in the
event that rust or worn surfaces appear, it may be necessary
to replace the bearings.

Next, inspect the stuffing box, and clean out any foreign matter
that might clog the box. Packing that appears to be worn, or no
longer regulates leakage properly should be replaced.
Mechanical seals should be cleaned and thoroughly flushed.

Couplings should be dismantled and thoroughly cleaned.
Lubricate the coupling with one of the coupling manufacturer’s
recommended lubricants where required.

Any pump that is properly sealed at all joints and connected to
both the suction and discharge should exclude outside liquid.
Therefore, it should not be necessary to go beyond the bearings,
stuffing box, and coupling when servicing the pump after flood
damage.

LUBRICATION

!

Bearings must be lubricated properly in order to prevent
excess heat generation, sparks, and premature failure.

GREASE LUBRICATIONOF
BEARINGS

Grease lubricated ball bearings are packed with grease at the
factory and ordinarily will require no attention before starting,

provided the pump has been stored in a clean, dry place prior to
its first operation. The bearings should be watched the first hour
or so after the pump has been started to see that they are operating
properly.

A lithium based NLGI-2 grade grease should be used for
lubricating bearings where the ambient temperature is above -20°
F. Grease lubricated bearings are packed at the factory with
Mobilux EP No. 2 grease. Other recommended greases are

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3409 IOM 11/04

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