April - Library

AMMJ Lessons Learnt In 45 Years of Condition Monitoring 24
Case study 3
Routine testing of the boiler feed pumps was done as at
Yallourn, with throttling in on the outlet valve to get headflow
test points over the widest range allowable. This
took some time and much physical operator effort.
Reflecting that internal wear has a consistent effect to the
head-flow curve, I realised that throttling was unnecessary,
as one or two points around the normal operating area
were enough. Testing now takes 15 minutes each pump
(Beebe, 2003) and later plants take advantage of their
DCS – see Figure 3).
Lesson #5 Review test procedures regularly,
to find if a test or procedure is in fact still
needed, or can be simplified or have its interval
stretched.
The UK experience
Based on my proposal to learn more about condition
monitoring, I was successful in getting a 2-year
travelling scholarship to work in the UK. (500MW boiler
commissioning (Babcock), turbine design and dynamics
(Parsons), and tests and investigations with the then CEGB). Unlike my home situation with the world’s cheapest
fuel, thermal efficiency was the priority, but its engineering effort shares much with condition monitoring. Following
a shaft crack in a 500MW unit, vibration monitoring had been further developed.
I returned full of ideas, and wrote 11 reports. Only one had a specific recommendation to spend money: to enhance
our vibration analysis capability by obtaining a real-time analyser, accelerometers, vector filer phase meter, plotter,
tape recorders, etc. The Power Generation Manager approved the largest expenditure on test equipment that
the technical heads in the power stations had ever seen. He did so on the condition that each station proved an
engineer to work with me in applying the equipment. This proved to be very wise, and gained “buy-in” at each
place that a superstar would not have gained working alone!
Lesson #6 If you find that worthwhile learning for your organization can only be obtained
outside it (whether in another country or not), make the proposal, but ensure that it is only you
that can be selected to go!
Lesson # To get buy-in, involve locals deeply in any development.
Figure 3 Boiler feed pump (4500kW): head-flow
data logged by DCS (truncated diagram).
Documented test procedures and program operation
I was assigned to the newest plant - Yallourn W (now called just “Yallourn” ( then with 2 x 350MW steam units) and
set up the CM program. Part of this was my belief that documented test procedures are essential, not only for our
CM people, but to get operating staff on side. We wrote about 25 of these documents.
[In 1987, I returned as a member of the management team. The station now had 4 units - 2 x 375MW had been
added. What had happened to the CM work? I found that more test procedures had been added- there were now
58! The CM team was led by a keen technical officer.
We produced a regular newsletter summarising our test work and results. (Recommendations for urgent action did
not await its publication!). Never more than one page, 70 copies were sent throughout the plant. Operators in
particular commented favourably, as did the plant manager.
At privatisation in 1995, the new owners found that the CM team had better maintenance records than the official
CMMS! Later, they won the CSi award for best CM program].
Lesson #8 For staff training and for briefing of relevant staff, document the procedures (include
digital pictures) and make then available to all on the company intranet.
Lesson #9 To ensure continuity of the CM program, estimate costs/benefits and maintain a
running score sheet. Even if only done for a sample period each year, worthwhile payback will
be shown. Publicise your activities modestly, admitting any shortcomings.
Lesson #10 Initial development of CM applications is well done or managed by professional
engineers, but ongoing routine CM is better run by technical staff whose career expectations are
likely to be less ambitious. Trades/craft people can also find this a fulfilling career.
Vol 24 No 2