Flowserve SVCN 7, Установка, эксплуатация и обслуживание

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SVCN 7 INSTALLATION, OPERATION, & MAINTENANCE
0.0005 in (0.013 mm) to 0.0015 (0.38 mm). If this clearance is exceeded, the impeller should be
replaced.
4.4.5 CHECKING RUNNING CLEARANCES
Running clearance is determined by measuring the inside diameter of the stationary part and the
outside diameter of the rotating part, then taking the difference between the corresponding
measurements and dividing by two to obtain the clearance. Measurements should be taken with a
micrometer and each part should be checked for trueness or roundness by taking readings 90° apart.
These parts should be replaced when running clearances have increased by 50 to 100% over the
design clearances listed on the Pump Assembly drawing in the back of this manual. Wear rings
should be replaced in accordance with paragraph 4.4.6 or paragraph 4.4.7 below.
4.4.6 REPLACING STATIONARY WEAR RINGS OR BUSHINGS
NOTE
For replacement of the case wear ring (26A) it is
recommended that the case be removed from the system and
transported to a suitable work area.
To replace a stationary wear ring (26A/B) or packing box bushing (610), proceed as follows:
CAUTION
Ensure that the parent part is not damaged during removal of
the wear ring.
1. Remove the wear ring retainers.
2. Remove the old wear ring by placing the parent part in a lathe and turning out the wear ring.
If this is not feasible, grind through the wear ring in two places and break the ring out of the
parent part.
CAUTION
Do not bind or distort the wear ring.
Ensure that the temperature of the parent part is above 70°F
(21°C) before installing wear ring.
3. Subcool the new wear ring in dry ice to shrink it; then, bottom the ring squarely in the bore of
the parent part by using an aluminum drift and mallet to strike evenly around the
circumference of the wear ring.
4. Allow the wear ring to return to ambient temperature before proceeding. Do not use any
artificial heat source, such as a torch or heat gun, to warm the wear ring.
5. Verify trueness of the wear-ring-to-part fit as outlined below, or by an equivalent technique:
a. Set up the parent part in a lathe or milling machine so that the register face of the parent
part can be used as a true side for a dial indicator. The centerline of the parent part must
be aligned with the centerline of the machine's table, and the parent part must be parallel
with table within 0.001 in. (0.03 mm).
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