Page 53 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

38 Major Process Equipment Maintenance and Repair

Where:
e = pump efficiency,
s.g. = specific gravity of the pumpage,
Q & H = as defined above.

Multiplying the normal pump power requirement by the percentage de-
termined in step 2 will yield the estimated wasted bhp resulting from ex-
cessive wear ring clearance.
Step 4-Figure 1-14 can now be used to estimate the increased annual
cost in your plant based on your location’s cost of electricity.

Pump Assembly Procedures*

Horizontal Process Pump Disassembly (Flgure 1-1 5)
Dismantling Rotating Element. The back pull-out design of the pump
shown in Figure 1-15 allows the complete rotating assembly to be re-
moved without disturbing the suction and discharge piping or the driver.
Disconnect all auxiliary piping and drain the oil from the bearing hous-
ing. After disconnecting the spacer type coupling (see separate instruc-
tions), remove casing stud nuts. Screw bolts into the tapped holes in the
casing cover (02) and tighten these jack bolts evenly to facilitate removal
of the rotating assembly. The complete rotating assembly can now be
moved to a clean area for further dismantling.

Dismantling Casing Cover with Mechanlcal Seal

After the complete rotating element has been taken to a clean work
area, the unit can be hlly dismantled by following these instructions and
referring frequently to the sectional drawing:

1. Remove impeller nut (21-1) {L.H. Threads}.
2. With a suitable puller, remove impeller (05).
3. Remove impeller key (1 1-1).
4. Unbolt seal gland (07-2) from casing cover and slide back against
deflector.

* Courtesy Union@ Pump (Canada) Ltd. Note that these procedures are typical and may
have to be modified to suit different pump models.