EBARA EFQT3 - Manual (Page 33)

EBARA Fluid Handling 33
Carefully wash all metallic parts in fresh
cleaning solvent and allow to dry thoroughly.
Do not attempt to separate the rotating
portion of the seal from the shaft sleeve
when reusing an old seal. The rubber
bellows will adhere to the sleeve during use,
and attempting to separate them could
damage the bellows.
Inspect the seal components for wear,
scoring, grooves, and other damage that
might cause leakage. Inspect the integral
shaft sleeve for nicks or cuts on either end. If
any components are worn, or the sleeve is
damaged, replace the complete seal; never
mix old and new seal parts.
Install the stationary seal element in the
stationary seat. Press this stationary
subassembly into the seal plate bore until it
seats squarely against the bore shoulder. A
push tube made from a piece of plastic pipe
would aid this installation. The I.D. of the
pipe should be slightly larger than the O.D.
of the shaft sleeve.
Slide the rotating portion of the seal
(consisting of the integral shaft sleeve,
spring centering washer, spring, bellows and
retainer, and rotating element) onto the shaft
until the seal faces contact.
Proceed with Impeller Installation and
Adjustment.
Impeller Installation
(
Figure 2)
Inspect the impeller, and replace it if cracked
or badly worn. Inspect the impeller and shaft
threads for dirt or damage, and clean or
dress the threads as required.
The shaft and impeller threads must be
completely clean before reinstalling the impeller.
Even the slightest amount of dirt on the threads
can cause the impeller to seize to the shaft,
making future removal difficult or impossible
without damage to the impeller or shaft.
Install the same thickness of impeller
adjusting shims as previously removed.
Apply Never-Seez or equivalent to the shaft
threads and screw the impeller onto the
shaft until tight. Be sure the seal spring seats
squarely over the shoulder on the back side
of the impeller.
NOTE
At the slightest sign of binding,
immediately back the impeller off, and
check the threads for dirt. Do not try to
force the impeller onto the shaft.
A clearance of .025 to .040 inch (0.64 to
1.02mm) between the impeller and the seal
plate is recommended for maximum pump
efficiency. Measure this clearance, and add
or remove impeller adjusting shims as
required.
NOTE
If the rotating assembly has been installed
in the pump casing, this clearance may be
measured by reaching through the priming
port with a feeler gauge.
NOTE
Proceed with Rotating Assembly Installation
before installing the impeller cap screw and
washer (10 and 12). The rotating assembly
must be installed in the pump casing in order to
torque the impeller cap screw.
After the rotating assembly is installed in the
pump casing, coat the threads of the
impeller cap screw (10) with ‘Never-Sees’ or
equivalent compound, and install the
impeller washer (12) and caps crew; torque
the cap screw to 90 ft. lbs. (1080 in.lbs. or
12.4 m.kg.)
Rotating Assembly Installation
(Figure 2)
NOTE
If the pump has been completely
disassembled, it is recommended that the
suction check valve and back cover
assembly be reinstalled at this point. The
back cover assembly must be in place to
adjust the impeller face clearance.
CAUTION!
CAUTION!