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Teikoku USA | Chempump

Instruction Manual G-Series

new bearing and then calculate if the new bearing length will put
end play back in tolerance. If end play still exceeds the maximum
allowable, then the impeller or front bearing housing seal faces
(and in the case of Models GVD, GVE, GVHS and GG the pump
casing seal faces) must be worn beyond a tolerable limit and must
be repaired or replaced. (It should be noted that under proper op-
erating conditions, wear on these parts due to axial thrust forces
will be negligible and will normally not require replacement.) At
the time the impeller seal face is inspected for wear, also visually
inspect the wearing rings and front impeller hub for any notice-
able signs of wear. If excessive grooving or scoring of the wear
rings or impeller hub is noticed, the impeller must be replaced.

Table 4-3. End Play

Model*

End-Play

Inch

GA, GB, GC

.084"-.104"

GVBS

.084"-.106"

GVE

.101"-.137"

GVD, GVHS

.032"-.068"

.102"-.138"

GVM

.068"-.096"

GLD

.067"-.073"

N2S

.040"-.060"

On Teikoku pumps with thrust bearings, the end play tolerances
are slightly different than new thrust bearing pumps. In GA, GB
and GC models the thrust is taken from the large flange on the
bearing and the gap between the rotor and front bearing. The
remaining models take the thrust from the impeller to the front
ring and the front bearing face to the rotor.

Table 4-4

indicates

end play tolerances for thrust bearing models.

Table 4-4. End Play on Thrust Bearing

Model*

End-Play New

Inch

GA, GB, GC

.086"-.140"

GVBS

.083"-.107"

GVE

.084"-.104"

GVD

.012"-.042"

GVHS

.022"-.042"

.050"-.070"

GVM

.030"-.056"

4.2.4 Stator Assembly Inspection

The complete stator assembly should be visually inspected for
cracks, breaks, pitting, or corrosion in the stator liner which might
destroy the effectiveness of the barrier. Inspect the wiring of the
stator assembly by checking the visible portion of the connector
leads for cracked, broken, or frayed insulation, then check the
condition of the motor windings by taking resistance readings
with an ohmmeter and a megger. If the ohmmeter readings are
not within 20% of the values shown in

Table 4-9

, the stator as-

sembly must be replaced.

4.2.5 General Inspection

1. Inspect the impeller nut threads on the rotor shaft to insure

they are not cut, pressed, or stripped. Models GA, GB, GC,
GVBS and GLD have left-hand threads. Models GVD, GVE,
GVHS, GG, GVM, and N2S have right-hand threads.

2. Be sure that all mating faces are free of nicks and burrs so that

they will present a smooth face, insuring a good seal. Clean
off any traces of old gasket material.

3. Make sure all parts are clean. Inaccessible areas may be cleaned

with a small brush or suit ably pointed tool. The circulation line
should be blown out with filtered, oil-free compressed air.

4.3 Lubrication

The G-Series pump requires no external lubrication. Bearing sur-
faces and other parts are lubricated and cooled by the fluid being
pumped.

4.4 Cooling

The motor rear bearing housing temperature is a direct indication
of the efficiency of the cooling and lubrication functions of the
fluid circulation through the motor section of the pump. If at any
time during operation the rear bearing housing appears overheat-
ed, check the temperature of the fluid being pumped. Check rear
bearing housing temperature with a thermocouple to assure that
it does not exceed the pumped fluid temperature (assuming that
no auxiliary means of cooling the recirculation flow is used such
as heat exchangers, jacketed circulation tubes, etc.). Rear bearing
housing temperature can also be checked by using a pyrometer or
a standard thermometer, held against the retainer by putty.

If the pumped fluid temperature is satisfactory, overheating is
most probably caused by a restriction in the circulation tube.

Table 4-2. Bearing and Journal Dimensions

Motor*

Shaft

Outisde

Dia. New

Bearings

Inside Dia.

New

Diametrical Clearnace

Bearings to Journal

Bearing Lengths