Flowserve ESP3 - Manual (Page 44)

ESP3 USER INSTRUCTIONS ENGLISH 26999943 08-11
Page 44 of 64
h) Inspect inside of bearings [3020.1-.2] in the
adapter [1340.1] and intermediate bearing
holder(s) [3250]. Check for cracks, uneven or
excessive wear, scoring or heat discoloration,
and corrosion. Bearings should be replaced as
described in Section 6.7.2.
6.8.2 Critical measurements and tolerances
To maximize reliability of pumps, it is important that
certain parameters and dimensions are measured
and maintained within specified tolerances. It is
important that all parts be checked. Any parts that do
not conform to the specifications should be replaced
with new Flowserve parts.
6.8.3 Parameters that should be checked by
users
Flowserve recommends that the user check the
measurements and tolerances in Figure 6-6
whenever pump maintenance is performed. Each of
these measurements is described in more detail on
the following pages.
6.8.3.1 Shaft
Replace if grooved, pitted or worn, especially where
the shaft rides in the sleeve bearings.
6.8.3.2 Bearings
It is recommended that rolling element bearings not
be used after removal from the shaft.
6.8.3.3 Impeller balancing
To minimize shaft whip it is imperative that the
impeller is balanced. All impellers manufactured by
Flowserve are balanced after they are trimmed. If for
any reason, a customer trims an impeller, it must be
re-balanced.
The maximum values of acceptable unbalance are:
•
Up to 1800 rpm: 40 g · mm/kg (0.021 oz-in/lb)
•
Above1800 rpm: 20 g · mm/kg (0.011 oz-in/lb)
Flowserve performs a single plane spin balance on
most impellers. The following impellers are
exceptions: 10X8-14, 10X8-16 and 10x8-16H. On
these Flowserve performs a two plane dynamic
balance, as required by the ASME B73.1M standard.
All balancing, whether single or two plane, is
performed to the ISO 1940 Grade 6.3 tolerance
criteria.
6.8.3.4 Vibration analysis
Vibration analysis is a type of condition monitoring
where a pump’s vibration “signature” is monitored on
a regular, periodic basis. The primary goal of
vibration analysis is extension on MTBPM. By using
this tool Flowserve can often determine not only the
existence of a problem before it becomes serious, but
also the root cause and possible solution.
Modern vibration analysis equipment not only detects
if a vibration problem exists, but can also suggest the
cause of the problem. On a centrifugal pump, these
causes can include the following: unbalance,
misalignment, defective bearings, resonance,
hydraulic forces, cavitation and recirculation. Once
identified, the problem can be corrected, leading to
increased MTBPM for the pump.
Flowserve strongly urges customers to work with an
equipment supplier or consultant to establish an on-
going vibration analysis program.