Teikoku USA | Chempump
Instruction Manual NC-Series 0220
21
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
, the stator
assembly must be replaced.
4.3.5 General Inspection
1. Inspect the impeller nut threads on the rotor shaft to ensure
they are not damaged. NC-Series have right hand threads.
2. Be sure that all mating faces are free of nicks and burrs so that
they will have a smooth face ensuring a good seal. Clean off
any trace of old gasket material.
3. Make sure all parts are clean. Inaccessible areas may be
cleaned with a small brush or pointed tool. The circulation line
should be blown out with filtered, oil free, compressed air.
4. The impeller face should be inspected for wear. If excessive
grooving or scoring of the wear rings is evident, the impeller
must be repaired or replaced.
4.4 Lubrication/Cooling
The NC-Series pump requires no external lubrication. Bearing
surfaces and other parts are lubricated and cooled by the fluid
being pumped.
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
anytime during operation the rear bearing housing appears
overheated, 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
by more than 15˚F. (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 be
checked by using a pyrometer or a standard thermometer held
against the retainer by putty.
If the fluid temperature is satisfactory, overheating is most probably
caused by a restriction in the circulation system. Shutdown pump,
drain unit, remove the circulation tube and clean it with clean, oil-
free, compressed air. If the unit still runs hot or if tube was clear,
the discharge filter may be clogged. Disconnect pipe connection
and inspect.
Caution!
Between cycles of pumping fluids which may solidify, such
as caustic soda, flush the system with steam, water or the
proper solvent to prevent the piping and internal passages
of the pump from plugging up. Where the Chempump
TM
is
fitted with a discharge filter, flush pump during off cycles
and check discharge filter for plugging.
4.5 Reassembly
1. Reassemble pump by reversing the disassembly procedure.
Replace all worn or corroded parts, and "o" rings throughout
the pump.
A. Before reassembly of the shaft sleeves and thrust washers,
clean the shaft of dirt, corrosion products, or residue.
B. Insert key.
C. Put the thrust washer on the shaft.
D. Put "o" rings on shaft.
E. Slide shaft sleeve on shaft, engaging the key, until it is
seated against the thrust washer.
F. Replace the shaft sleeve retainer in the rear and the impeller
in the front.
2. Complete reassembly. However, before bolting the motor
section to the pump casing, spin the rotor impeller assembly
by hand to insure that it does not bind.
3. In reassembling the inducer, care must be taken to completely
tighten the impeller nut against the impeller to insure that it
securely holds the impeller against the shaft shoulder. A strap
wrench is recommend to hold the impeller assembly while
tightening the impeller nut.
4.6 Service Policy
Any pump, damaged or inoperative for any reason, will be repaired
at the factory at minimum cost and returned to the customer as
quickly as possible.
Caution!
Before returning units to the factory for examination or
repair,
clean and decontaminate the pump or parts
thoroughly to prevent corrosive attack during ship-
ment or injury to personnel handling returned equip-
ment. Tag pump with information regarding the fluid
it was handling and operating conditions at the time
of failure.
Proper service will be facilitated with the prop-
er submittal of a Teikoku Field Service Report Form. These
forms are available from the factory , from the Teikoku
field representatives, and from this instruction manual Ap-
pendix.
4.7 Spare Parts
Have on hand at least two extra sets of bearings, two extra sets of
"o" rings, and one extra rotor assembly for each NC-Series that
is installed.
When ordering spare parts, give the serial number and model
designation; then give the part name which is noted on Cross
Section Drawing in the Appendix.
When ordering an impeller, include the impeller diameter which
can be noted from the pump order acknowledgment or from the
pump nameplate.
Please note, spare part kits, that include all the components listed
on the opposite column, packaged together are available. Please
