Teikoku USA | Chempump
Instruction Manual HE-10677-P (1018)
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1.2 Stator Assembly
The stator assembly consists of a set of three-phase windings.
Stator laminations are of low-silicon grade steel. Laminations
and windings are mounted inside the cylindrical stator band. End
bells, welded to the stator band, close off the ends of the stator
assembly. The stator liner is, in effect, a cylindrical can placed in
the stator bore and welded to the rear end bell and front end bell
to hermetically seal off the windings from contact with the liquid
being pumped.
Terminal leads from the windings are brought into an electrical
terminal box. Motor lead wires are isolated from the users’ con-
duit line by a leakproof terminal plate assembly mounted inside
the terminal box. The design of the stator assembly in conjunction
with the leakproof terminal plate assembly provides an advanced
low probabilty true positive secondary containment.
1.3 Rotor Assembly
The rotor assembly is a squirrel cage induction rotor constructed
and machined for use in the Teikoku Type-R (Plan 13-SE). It con-
sists of a machined corrosion-resistant shaft, laminated core with
cast aluminum bars and end rings, corrosion-resistant end covers,
and a corrosion-resistant can.
The rotor end covers are welded to the shaft and also to the
rotor can which surrounds the outside of the rotor, thus her-
metically sealing off the rotor core from contact with the liquid
being pumped.
The impeller is keyed to the shaft and held in place with a bolt and
lockwasher. The shaft is fitted with replaceable shaft sleeves and
thrust collars. These parts are pinned or keyed to prevent rotation.
Axial movement is restricted by the thrust collars contacting the
face of the front and rear bearings.
1.4 Liquid Film Journal Bearings
The liquid film journal bearings for the Teikoku Type-R (Plan
13-SE) are carbon graphite as standard and are machined with
special helix grooves through the bore to assure adequate liquid
circulation at the journal area. Each liquid film journal bearing is
manufactured to close tolerances for a high degree of concentric-
ity and is held in a bearing housing by a retaining screw. Liquid
film journal bearings are easily replaced by removing the retaining
screw and sliding the bearing from its housing.
1.5 Thrust Collars and Shaft Sleeves
All Teikoku Type-R (Plan 13-SE) models are equipped with thrust
collars, providing a replaceable surface against which axial loads
can be carried during process upset conditions. The shaft is also
fitted with replaceable shaft sleeves. Both the thrust collars and
shaft sleeves are constructed of 316SS with a Stellite wear surface
for long life. These parts are pinned or keyed to prevent rotation.
1.6 Cooling Flow
Flow paths of the Teikoku Type-R (Plan 13-SE) reverse circulation
pumps are shown in
. The circulating liquid is chan-
neled into the motor section by holes drilled in the front bearing
housing. A portion of the circulating liquid lubricates the front
liquid film journal bearing and returns to the rear of the impeller.
The remainder of the circulating liquid passes over the rotor cools
the motor, lubricates the rear liquid film journal bearing and then
exits the rear bearing housing returning to the vapor space of the
suction tank via the reverse circulation line. The Teikoku Type-R
(Plan 13-SE) reverse circulation design avoids the heated circulat-
ing liquid returning directly to the pump suction.
1.7 Automatic Thrust Balance
Based on hydraulic principles, Teikoku Type-R (Plan 13-SE) au-
tomatic thrust balance is accomplished by the pressure of the
pumped liquid itself, operating in a balance chamber at the front
and rear of the impeller.
When a change in load shifts the position of the impeller away
from the balance condition, there is an equalizing change of
hydraulic pressure in the balance chamber, which immediately re-
turns the impeller-rotor assembly to the balanced position.
