Page 62 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Installation, Maintenance, and Repair of Horizontal Pumps 47

7. Slide shaft and impeller assembly from casing cover.
8. Remove impeller retaining rings and press impeller from shaft.
9. Case wear rings, throat bushings and impeller wear rings are tack-
welded in place. Grind tack-weld off and remove rings and bush-
ings.

After inspection of parts has been carried out and relevant dimensions
recorded for future reference, reassembly can be carried out following
these procedures:

I. Press case wear rings, throat bushings and impeller wear rings into
place and tack weld in three places.
2. Install one impeller retaining ring and impeller key, and press im-
peller on shaft against ring.
3. Install second impeller retaining ring.
4. Return all parts to casing and with coupling end first place shaft
and impeller assembly into casing.
5. Install gaskets, inner gasket into case and outer gasket on cover, and
hold in place with heavy grease.
6. Slide casing cover over shaft (watch bearing surfaces and threads)
and bolt into place.
7. Reassemble stuffing box.
8. Reassemble bearing housing.

Reassembllng Casing Cover wlth Mechanical Seal

After inspection has been carried out as outlined in the inspection sec-
tion, and all parts are cleaned and corrected as necessary, the casing
cover can be reassembled by following the instructions given below and
by frequently referring to the appropriate sectional drawing, Figure 1-15
or Figure 1-16.
1. Press throat bushing (47-1) into casing cover (02).
2. Press case ring (08-2) into casing cover (02) and tack weld in three
places.
3. Press throttle bushing (47-3) into seal gland.
4. Insert stationary seal face into seal gland (07-1), being careful not
to damage O-ring or seal face.
5. Slide gland over shaft against deflector and place sleeve gasket
(15-3) on shaft.
6. Install rotating assembly of mechanical seal on shaft sleeve. For
special seals follow instructions given separately; for standard
seals use the following procedure: