GE GEK-95352 User Manual
Instructions
Vertical Induction Motors
GEK-95352
GE Industrial Systems
High Thrust
Hollow and Solid-Shaft
In-Line Solid-Shaft
Frames 444-5011 NEMA Type P Base
Weather Protected Type I and Type II
GEK-95352
CONTENTS
Subject Page
Safety Precautions......................................................................................................................................3
Introduction................................................................................................................................................4
Cross-Sectional Drawings..............................................................................................................24, 25, 26
Receiving, Handling and Storage................................................................................................................5
Unpacking...............................................................................................................................................5
Installation..................................................................................................................................................6
Location and Mounting............................................................................................................................6
Pump and System Precautions..................................................................................................................6
Alignment of Solid-Shaft Motors.............................................................................................................7
Couplings for Hollow-Shaft Motors.........................................................................................................7
General.................................................................................................................................................7
Self-Release Couplings.........................................................................................................................7
Bolted Couplings ..................................................................................................................................9
Non-Reverse Couplings ........................................................................................................................9
Power Supply and Connections..............................................................................................................10
Wiring and Grounding........................................................................................................................ 10
Allowable Voltage and Frequency.......................................................................................................10
Position of Conduit Box ...................................................................................................................... 11
Lubrication............................................................................................................................................11
Water Cooling.......................................................................................................................................11
General...............................................................................................................................................11
Oil Cooling Coil Connections ............................................................................................................. 11
Connection Fitting Drawing................................................................................................................12
Operation..................................................................................................................................................12
Safety Warnings .................................................................................................................................... 12
Steps Prior to Initial Start-Up................................................................................................................. 12
Initial Start.............................................................................................................................................14
Jogging and Repeat Starts......................................................................................................................14
Maintenance............................................................................................................................................. 15
Safety Warning......................................................................................................................................15
General..................................................................................................................................................15
General Cleanliness ............................................................................................................................... 15
Coupling Maintenance........................................................................................................................... 15
Relubrication.........................................................................................................................................16
Oil Viscosity (Table II).......................................................................................................................... 17
End-Play Adjustment............................................................................................................................. 17
General...............................................................................................................................................17
Ball Thrust Bearings........................................................................................................................... 17
Spherical Roller Thrust Bearings......................................................................................................... 18
Bearing Replacement............................................................................................................................. 19
Oil Cooling Coil Maintenance................................................................................................................19
Insulation and Windings ........................................................................................................................20
General...............................................................................................................................................20
Vacuum and Compressed Air Cleaning............................................................................................... 21
Cleaning with Water and Detergent..................................................................................................... 21
Cleaning with Solvents .......................................................................................................................21
Revarnishing Windings.......................................................................................................................22
Renewal Parts........................................................................................................................................... 22
Trouble-Shooting Chart............................................................................................................................23
2
Safety Precautions
GEK-95352
High voltage and ro tating p arts
can cause serious or fatal injury. Installation, operation
and maintenance of electric
machinery should be performed by q ualified personnel.
Familiarizat io n wit h NEM A
Publication MG-2, Safety Standard for Construction and Guide for Selection, Installation and
Use of Electric Motors and Gen erators, the National Electri cal Code and sound local practices
is recommended.
For equipment covered b y t hi s instruction boo k,
it is important to observe saf ety precautions t o
protect personnel from possible injury. Among
the many considerations, personnel should be
instructed to:
•
Avoid contact with energized circuit s or rotating parts,
•
Avoid by-passing or rendering inoperative
any safeguards or protective devices,
•
Avoid use of automatic-reset thermal protection where unexpected starting of
equipment might be hazardous to personnel.
•
Avoid contact with capacitors until safe discharge procedu res have b een foll ow ed.
•
Be sure that the shaft key is fully captive
before the motor is energized.
•
Avoid extended exposure in close proximity
to machinery with high noise levels.
•
Use proper care and procedures in handling, lifting, installing, operating and maintaining the equipment.
•
Do not lift anything but the motor with the
motor lifting means.
Safe maintenance practices with qualified personnel are imperative. Before starting maintenance procedures, be positive that:
•
Equipment connected to the shaft will not
cause mechanical ro t ati on ,
•
Main machine windings and all accessory
devices associated with the work area are
disconnected from electrical power sources.
If a high potential insulation test is required,
procedures and precautions outlined in NEMA
Standards MG-1 and MG-2 should be followed.
Failure to properly ground the frame of the machine can cause serious injury to personnel.
Grounding should be in accordance with the
National Electrical Code and consistent with
sound local practice.
These instructions do not purport to cover all of the details or variations in equipment nor to provide for every possible
contingency to be met in connection with installation, operation or maintenance. Should further information be desired or
should particular probl ems arise which are not covered sufficiently for the purchaser’s purposes, the matter should be referred to the General Electric Company.
1988, 1999 General Electric Company
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GEK-95352
I. INTRODUCTION
General Electric high-thrust vertical motors covered by these instructions are
carefully constructed of high-quality materials and are designed to give long and
trouble-free service when properly installed and ma intained. These motors are
generally used to drive pumps.
Both HOLLOW-SHAFT and SOLIDSHAFT motors are described in this instruction book. Figure 1 shows a typical
ho llow-shaft high- thru s t mot or. T he solid shaft construction is similar except that
the top half-coupling is omitted, and the
motor shaft extends out the bottom of the
motor. See Figure 2. Solid-shaft highthrust motors are not suitable for driving
loads that impose significant radial load
on the motor shaft; they should not, for
example, be used for belt-drive applications.
thrust and one or two oriented to carry
down-thrust. If greater down-thrust capacity is required, motors may use one or
two standard angular-contact ball bearings and one split-race bearing which
gives the capacity of two or three bearings down and one bearing up. This does,
however, give more end-play than normal.
IN-LINE motors (designed to be mounted
on pumps which are directly in the p ipeline, and hence called IN-LINE motors)
are also covered by this instruction boo k.
These motors have two opposed-mounted
angular-contact ball thrust bearings at the
top end of the motor so they can carry
either up or down thrust. The lower guide
bearing is a radial-ball type and also carries any radial load imposed by the pump.
IN-LINE motors are always of the solidshaft type. This construction is shown on
the left side of Figure 3.
Motors may be supplied with different
bearing arrangements for various external
thrust conditions imposed by the pump,
such as different magnitudes of downthrust and either momentary or continuous up-thrust. A typical high-thrust motor
with angular-contact ball bearings is
shown in Figure l. This standard construction is for high continuous downthrust and is suitable for momentary upthrust equal to 30% of the rated downthrust capacity of a high-thrust motor.
NOTE THAT ANGULAR-CONTACT
BEARINGS CAN ONLY CARRY
THRUST IN ONE DIRECTION.
Figure 3 shows a typical solid-shaft highthrust constructio n (o n right side) for applications requiring continuous up-anddown thrust capability. In this type of
motor, two or three angular-contact ball
bearings are mounted in opposed mounting with one bearing oriented to carry up-
Spherical-roller bearings are sometimes
used for applications requiring extra high
down-thrust capac ity and/or extr a bearing
life; these bearings may require watercooling. See Figure 2. Motors with
spherical-roller thrust bearings also require certain minimum down-thrust during all continuous operation.
Since overloading greatly reduces bearing
life, the amount of thrust applied should
not exceed the recommended values.
This instruction book applies to motors
with either Weather-Protected I or
Weather-Protected II enclosures as de-
fined by NEMA. Both of these are “open"
motors. (WP-II enclo sure is not available
in 440 frame series.)
Weather-Prot ect ed I motor co nstruct ion is
shown in Figure 1 for 500 frame motors
and in Figure 3 for 440 frame motors.
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GEK-95352
Weather-Protected II motor construction
is shown in Figure 2. This enclosure is
characterized by additional protection at
the air inlet and outlet passages and by
gaskets, drains, and other features to
make it suitable for use outdoors in se vere
climates. Filters can be supplied for the
air-inlet openings. When used, they
should be cleaned periodically, since
clogged filters restrict the amount of
cooling air and cause the motor to overheat. Gages are so metimes used t o measure the pressure dro p across the filter and
thus indicate its condition. Filters should
be cleaned when the gage reads over 0.4”
of water.
II. RECEIVING, HANDLING AND
STORAGE
Each motor should be carefully examined
when received and a claim filed with the
carrier for any damage. The nearest o ffice
of the General Electric Company may offer guidance.
The motor should be lifted by
the lugs provided. These lugs
are intended for lifting the motor only and must not be used
to lift any additional weight. Be
careful not to touch overh ead
equipment. Failure to observe this warning
may result in personal injury or death.
If the mo t o r is no t to be ins t a lle d immed iately, it should be stored in a clean, dry
location. Precautions should be taken to
prevent the entrance of moisture, dust, or
dirt during storage and installation. Precautions are taken by the factor y to guard
against corro sion. The machined parts ar e
slushed to prevent rust during shipment.
Examine the parts carefully for rust and
moisture, if the equipment is to be stored,
and re-slush where necessary.
Motors are shipped without oil in the
bearing reservoirs. An oil film remains on
the bearings, but if the storage period is t o
exceed three months, the reservoirs
should be filled. It is suggested that such
oil-filled motors be conspicuously tagged
in order to prevent mishandling, which
would cause oil spillage and subsequent
damage to the internal parts of the motor.
When filling for storage, fill to the maximum level shown on the gage or approximately ½” over the mark showing
the standstill level. Before operating the
motor, dr ain this oil and refill w ith fres h
oil.
See instructions under RELUBRICATION for oil r eco mmendat ions.
During storage, windings should be protected from excessive moist ure abso rption
by some safe and reliable method of
heating. Space heaters, if supplied, may
be used fo r this purpose. The temperature
of the windings should always be maintained a few degrees above the temperature of the surrounding air. It is recommended that motors in storage be inspected, the windings meggered, and a
log of pertinent data kept. Any significant
decrease in insulation resistance should
be investigated.
If a motor is to be in st orage for over o ne
year, it is recommended that competent
technical inspection service be obtained
to ensure that the storage has been adequate and that the motor is suitable for
service. Contact your nearest General
Electric Sales office to arrange for inspection service.
A. Unpacking
If the machine or machine parts have
been exposed to low temperature, unpack
it only after it has reached the t emperature
of the room in which it will be unpacked
or located; otherwise sweating will occur.
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GEK-95352
III. INSTALLATION
Installation should be in acco r-
dance with the National Electri-
cal Code and consistent with
sound local practi ces. Coupling
guards should be installed as
needed to protect against accidental contact with moving parts. Machines
accessible to personnel should be further
guarded by screening, guard rails, or other suitable enclosure to preven t anyone from coming
in contact with the equipment. This is especially
important for motors that are remotel y or automatically controlled or have automatic resetting overload relays, since such mo tors may
start unexpectedly. Failure to observe these
precautions may result i n inju ry o r deat h to personnel.
A. Location and Mounting
Allow enough space around the motor to
permit free flow of ventilating air and to
maintain an ambient temperatur e not over
40° C. Where a choice of locat ions is possible, install the motor so that it will be
subjected to the least amount of dirt, dust,
liquids, or other harmful materials. Mount
the motor securely on a level, firm fou ndation, align accurately with the driven
equipment, and tighten mounting bolts
securely.
Weather-Prot ected Type I motors may be
installed in indoor locations with relatively high moisture content or sheltered
outdoor locations in dry climates.
Weather-Protected Type II motors may be
installed outdoors. Use filters in unclean
areas.
If ignitable dust or lint is present the surface temperature of
space heaters, if supplied,
should not exceed 80% of the
ignition temperature. Refer to
space heater nameplat e or factory for information on surface temperature.
Dust and-or lint should not be allowed to build
up around the surface of space heaters. Failure to observe these precautions may result in
damage to equipment, injury to personnel or
both.
A. Pump and System Precautions
Some precautions are nece ssary to assure
satisfactory operation of motors in
pumping service. The packing gland in
the pump head should be kept in good
condition so t hat t he liquid be ing pu mped
will not be forced out along the shaft and
enter the motor through the lower bearing
housing.
Motors driving pumps in pressure systems where the pressure is maintained
after shutdown should be protected from
over speeding by check valves, or nonreverse couplings.
Installation of the machine
where hazardous, flammable, or
combustible vapors or dusts
present a possibility of explosion or fire should be in accor-
dance with the National Electrical Code, Articles 500-503, and consistent wi th
sound local practi ces. Extreme care is required
for machines supplied with an explosion-proof
or dust-ignition proof accessory device or conduit box since any nicks or burrs in the sealing
surfaces during disassembly and reassembly
may destroy the explosion-proof or dustignition proof features. Failure to observe
these precautions may re sult in damage to the
equipme nt, injury to pers onne l, or bot h.
6
GEK-95352
The SYSTEM REED CRITICAL
FREQUENCY should be 25% above or
below motor operat ing speed in order to
avoid excessive vibration.
C. Alignment of Solid-Shaft Motors
Accurate mechanical lineup is essential
for successful operation. Mechanical vibration and roughness when the motor is
running may indicate poor alignment. In
general, lineup by straight edge across,
and feeler gages between coupling halves
is not sufficiently accurate. It is recommended that the lineup be checked with
dial indicators. The space between coupling hubs should be maintained as recommended by the coupling manufacturer.
D. Couplings for Hollow-Shaft
Motors
To prevent breakage, coupling bolts
must be tightened to torque values
indicated below for bolted or nonreverse couplings
Bolt Size Torque
1/2 90 lb-ft
5/8 180 lb-ft
3/4 320 lb-ft
1 710 lb-ft
It shall be the installer’s responsibility in all cases to ascertain that these torq ue values
are used and maintained. This
shall include those instances
when the coupling comes mounted in the motor. Failure to comply may cause the coupl in g
bolts to break, with resultant extensive damage
to the equipment.
2. Self-Release Co uplings
1. General
Vertical hollow-shaft motors are
designed for driving deep-well, turbine-type pumps and can be
equipped with either self-release,
bolted, or non-reverse couplings as
described in following sections.
These couplings are located at the
top of the motor and allow pump
impeller position to be ad justed easily. The type of coupling is specified
by the customer. Remove the top
cap for access to the coupling.
Two slots are provided in the outside rim of the coupling so that a bar
can be inserted to keep t he assembly
from turning while the adjustment
of pu mp impeller clear ance is bein g
made. A coupling bolt can be
screwed into one of the extra tapped
holes in the top endshield to provide
a stop for the bar.
Should the motor accidentally be
run in the reverse direction, the
pu mp line - sh a ft joi nt s ma y u nsc r ew .
The self-release coupling acts to
limit the amount of this unscrewing.
In normal o per ation, to rque from the
motor is transmitted by the lower
half-coupling through the driving
pins to the upper half-coupling, and
then to the pump shaft. If reversal
occurs and the pump shaft st arts to
unscrew and lengthen, the upper
half of the self-release coupling is
lifted up off of the driving p ins, t hus
uncoupling the pump from the motor. See Figure 1, where a selfrelease coupling is shown to the left
of the shaft center - line.
NOTE : THAT SELF-RELEASE COUPLINGS CANNOT CARRY UPTHRUST
Proper functioning of a self-release
coupling depends upon several factors. The pump shaft adjusting nut
must be securely attached to the top
7
GEK-95352
half-coupling, and the top halfcou plin g mus t not bind on t he low er
half. Otherwise, the adjusting nut
lock-screw may break instead of the
coupling halves separating. Should
this happen, the motor would continue to drive the pump line shaft,
and the joints would continue to unscrew. Serious damage to both motor and line shaft may result. Clearance between the coupling halves
should be checked by placing the
top half-coupling in position prior to
installing the motor. It should drop
into place, and rest solidly on the
lower half-coupling, without forcing.
Proper alignment of the pump headshaft within the motor hollow shaft
is also impo rt ant . Aft er t he c o uplin g
re le a s es it no lo n g e r h o ld s t h e pump
shaft centered. If the alignment is
not good, the motor shaft which is
stil l ro t at ing ma y ru b the pump sha ft
which has st opped, and damage will
result.
Table 1
Frame Size XH
444-449 4.38”
509-5011 4.88”
Depending upon the circumstances
causing reversal and upon which
line-shaft joint unscrews, there may
be enough energy stored in the rotating parts, at the time the coupling
clears the pins, to cause the pump
shaft to continue to rise and strike
the top cap. However, if the above
conditions are met, damage, even in
the most severe cases, should be
limited to a broken cap.
It is intended that self-release couplings will be called upon to uncouple only infrequently.
NOTE: ANY TIME A SELF-RELEASE
COUPLING UN-COUPLES, IT IS
NECESSARY T0 REMOVE ALL
POWER AND MANUALLY RECOUPLE.
A third requirement is that the distance between the top of the pump
shaft and the inside of the top cap be
at least enough to allow the t op halfco up lin g, whe n it t rie s t o r elea se , t o
clear the pins before the shaft hits
the cap. Check this clearance after
the adjust ing nut has been d raw n up
to its final position. To facilitate
making the check, the motor outline
print shows a maximum dimension
"XH" from the top of the coupling
to the top of the pump shaft. Adhering to this design limit will allo w
the shaft and coupling to lift enough
to clear the pins and still leave a
small clearance between the shaft
and cap. For standard motors, “XH”
is as s how n in Tabl e 1.
Uncoupling is most frequently
caused by application of singlephase power after a power supply
disturbance, while the motor is being driven in the reverse direction
by the pump; this single-phase
power causes the motor to take over
and drive the pump in the reverse
direction and the pump shaft joints
will then unscrew. To prevent this,
select a motor start er which requires
a manual start after any stop (r ather
than allowing automatic re-start as
soon as power is applied to the
starter), or incorporates a back-spin
timer to keep power from being
automatically reapplied to t he motor
until enough time has elapsed for
water back-flow through the pump
to stop and for the motor to completely stop.
8
GEK-95352
Power supply phase-sequence reversal will also cause the motor to reverse and unscrew the pump shaft,
but this rarely occurs. An antiphase-reversal relay can be incorporated in the motor controller if desired.
To prevent uncoupling on initial
start-up, check motor rotation direction before installing the upper halfcoupling to be sure direction is correct. To reverse direction of rotation, interchange any two power
leads.
2. Bolted Couplings
Bolted couplings allow up-thrust
from the pump to be taken by the
motor bearings. This type of coupling is similar to a self-release
coupling except that the driving pins
are replaced by bolts, whic h shou ld
be securely tightened to hold the
two halves of the coupling solidly
together so that torque is transmitted
by face friction. See torque requirements. This type of coupling
does not have the self-release feature and allo ws reverse rotation.
See the self-release coupling shown
to the left of the motor centerline in
Figure 1, which is applicable to
bolted couplings except that the
headless drive pins are replaced by
bolts as explained above.
4. No n-Reverse Couplings
from unscrewing, but it also prevents damage from overspeeding
and damage to water-lubricated
pump shaft bearings, when during
shutdown the residual water in the
system drives the pump in the reverse direction. This type of coupling also allows up-thrust from the
pump to be carried by the motor
bearings. Motor torque is transmitted to the pump shaft through the
two halves of the coupling which
are bolted together. See required
bolt torques.
The operation of a non-reverse co upling is explained as follows. When
the motor is started in the correct or
forward direction, the ratchet pins
are lifted by the ratchet teeth, and
are held up by centrifugal force and
friction when motor speed becomes
high enough. When power is removed, the speed decreases, a nd the
pins fall. At the inst ant of reversal, a
pin will catch on a rat chet tooth and
prevent backward rotation. The
number of pins differ from the
number of teeth to multiply the
number o f stopping posit ion s.
A very rapid decrease in speed can
result in acceleration forces great
enough to prevent the pins from
dropping. This condition is further
aggravated when the pins become
dirty, and their action sluggish. If
the t ime fro m shut down (t he inst ant
the “stop” button is pressed) to zero
speed is greater than two seconds,
operation will be satisfactory.
The non-reverse type of coupling, as
shown to the right of the motor
centerline in Figure 1, is also a
bolted type, and, in addition, it
keeps the pump and motor from rotating in the reverse direct ion. Thus,
it not only prevents the pump shaft
To permit operation when stopping
time is less than two seconds, the
pins are spring-loaded. For those
cases involving cycling (frequent
starting and stopping) and stopping
times greater than two seconds, the
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