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5. After the pump is operating at full speed, slowly
open discharge valve. If driver overheats or there is
excessive vibration, stop the pump, determine the
causes and correct them.
Improper impeller adjustment could cause
contact between the rotating and stationary
parts, resulting in a spark and heat generation.
6. If the air release valve is manually operated, close it.
7. For open lineshaft pumps, with the pump in
operation, there should be some leakage at the
stuffing box packing. The correct leakage rate is
approximately one drop per second. Check the
temperature of the leakage as well as the discharge
head. If the pump runs hot and the leakage begins
to choke off, stop the pump and allow it to cool
down. A few light taps with a hammer on the gland
will upset the packing sufficiently to resume leakage.
After pump has cooled, restart pump and follow
preceding procedure. Run pump 15 minutes, check
leakage. If it exceeds two drops per second, adjust
packing as described in "Packing Adjustment and
Replacement".
8. For pump with mechanical seal, if seal leaks slightly
at startup, allow a reasonable amount of time for
seal to adjust itself. Liquids with good lubricating
qualities normally take longer to wear in the seal
than liquid with lesser qualities. When a seal starts
out with a slight leak and gets progressively less
while running, it is indicative of leakage across the
seal faces. Continued running will eliminate this.
Where leakage occurs immediately and remains
constant, unaffected by running, it usually indicates
secondary seal (Shaft packing) damage, or seal faces
are warped out of flat.
Maintenance – SECTION 5
PREVENTIVE MAINTENANCE
Before initiating maintenance procedures,
WARNING
disconnect (utilizing proper logout/
tagout procedures) all energy sources to the equipment
and accessories and completely discharge all parts and
accessories which retain electric charge. Failure to
comply may result in severe personnel injury or death.
Preventive maintenance includes periodic inspection
of oil level in the oil reservoir (for pump with oil lube
column), re-lubrication of electric motors, gear drives
and prime mover. Systematic inspection of the pump
and its components shall be made at regular intervals.
The frequency required depends upon the operating
conditions of the pump and its environment. See
following Preventive Maintenance Schedule. Consult
the applicable manufacturer's instructions for detailed
information on maintenance for the prime mover,
driveshaft, electric motors and gear drives. Any deviation
in performance or operations from what is expected can
be traced to some specific cause. Variances from initial
performance will indicate changing system conditions,
wear, or impending breakdown of the unit.
PREVENTIVE MAINTENANCE SCHEDULE
PROCEDURE
Clean dirt, oil and grease from
driver and discharge head.
Clean driver ventilation passage to
prevent overheating.
Change lubrication in gear drive.
Tighten all loose bolts and check
for excessive vibration.
If packing is grease lubricated,
add as required.
Check that there is some leakage
through stuffing box while pump is
in operation. Do not tighten gland
nuts unless necessary.
Maintain a liquid film of lubrication
between the seal rubbing faces.
Re-grease the motor bearings:
1800 RPM and above
Below 1800 RPM
PACKING ADJUSTMENT AND REPLACEMENT
Pumps equipped with packing, shall be adjusted
whenever the leakage rate exceeds two drops per second.
If there is no leakage or the stuffing box overheats, do
not back off gland nuts while the pump is running. This
will allow the entire set of rings to move away from the
bottom of the box, without relieving pressure of the
packing on the shaft. Stop the pump and allow packing
to cool then restart the pump.
Be sure to reinstall the coupling guard
WARNING
before restarting the pump.
It may be necessary to repeat this procedure several
times before proper amount of liquid comes through to
efficiently prevent overheating. If leakage is excessive,
adjust the stuffing box as follows:
1. With the pump in operation, tighten the gland nuts
one-quarter turn for each adjustment. Allow packing
to equalize against the increased pressure and
leakage to gradually decrease to a steady rate, before
making another adjustment.
Do not over tighten the stuffing box.
CAUTION
Excessive pressure can wear out packing
prematurely and seriously damage the shaft.
2. With the pump shut down and when packing has
been compressed to the point that the gland is about
to contact the upper face of stuffing box, remove the
split gland, add one extra packing ring and readjust.
If this fails to reduce leakage to two drops per
second, remove all packing rings and replace with
new rings.
3. Remove the packing with the aid of a packing hook.
If a lantern ring is provided, remove it by inserting
a wire hook in the slots of the ring and pull it from
the packing box. Thoroughly clean the stuffing box
of all foreign matter.
TIME INTERVAL
(in operating hours)
As required
As required
2,000 or once a year
As required
100
As required
As required
Refer to Motor IOM
Refer to Motor IOM
21
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