Carver RS A, Installation, Operation And Maintenance Manual

Page: 23 / 67

RS Series – Multi-Stage, Ring Section Pumps January 2001
17
Table 9. Pumping Unit Troubleshooting (CONT.)
Symptom Immediate Action Probably Cause Corrective Action
Driver overloaded. 1. Stop driver. 1. Pump discharge
pressure is lower
than design point
(check pump
nameplate)
1. Partially close
discharge valve until
pressure at
discharge flange is
as specified.
Decrease speed or
trim impellers if driver
remains overloaded
(consult Carver
Pump Company
before taking this
step).
2. Same as 3 under
“Pump Discharge
Pressure Excessive.”
1. Same as 3 under
pump discharge
pressure excessive.
3. Wrong impeller trim. 1. Trim outlet tips of
impeller vanes.
Consult Carver Pump
Company specifying
exact operating
conditions.
V. Maintenance and Repair
A. Scheduled Maintenance
The pump should always run quietly and
smoothly, without vibration. To ensure such
operation, the following maintenance schedule
should be applied at regular intervals during
operation of the pump. A pump service record
and an inspection and repair record are provided
for this purpose in the front matter of this
manual.
Daily Inspection:
•
Visually inspect unit.
•
Check bearing temperatures.
•
Refer to Table 3, to check bearing cooling
flow rates, if applicable.
•
Check for leakage at mechanical seals.
•
Check for oil level, if applicable.
Weekly Inspection:
•
Check power (amps) readings.
•
Check pump discharge pressure. Prescribed
operating discharge pressure should never
drop below 90 percent of design point
pressure.
•
Check vibration on pump and driver
bearings. Vibration should NOT exceed 1.8
overall displacement (unfiltered) peak to
peak mils (0.001”) at 3600 RPM and 3.5
overall displacement (unfiltered) peak to
peak mils (0.001”) at 1750 RPM.
Monthly Inspection:
•
Check coupling alignment.
•
If necessary, grease coupling. Do NOT over
grease.
•
Check foundation bolts.
Semi-annual Inspection:
•
Grease bearings. Do NOT over grease or
add excess oil.
•
Check coupling alignment due to settling of
foundation.
•
If stand-by pumps are installed, it is
advisable to operate pumps on a rotation
system to give each pump a certain duty.
This ensures that stand-by pumps will
always be in good condition for instant start-
up.
B. Bearings
The thrust bearings are installed back-to-back.
The standard package has a matched set of
bearings located on the suction end. The
optional package has a matched set of bearings
located on the discharge end with a single
bearing on the suction.