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Nipsco Plant Installation
Power company eliminates the cost
of rotating and
replacing ash removal pipelines by installing pipe with
abrasion resistant linings
information - This article was prepared through joint efforts
between Abresist Corp., Urbana, IN and Nipsco, R.M Schahfer
Station, Wheatfield, IN.
Nipsco has eliminated the cost of rotating and
replacing ash removal pipelines by installing pipe with abrasion
resistant linings at the four coal-fired units of the R. M.
Schahfer Station in Wheatfield, IN. The four generators produce
in excess of 1,800 megawatts of power.
The station began operation in 1975 with the
commissioning of the 500 megawatt Unit 14. Unit 15, also 500
megawatts, was commissioned in 1979. Both units have UCC ash
removal systems. The original bottom ash pipe was hardened
cast iron and after four years it was necessary to rotate
the Unit 14 pipe to lengthen its life.
Because of the short 5-8 year life expectancy
of the cast iron, the utility began looking at alternatives
while Units 17 and 18 were still in the planning stages. Several
lining materials were evaluated and the company chose ABRESIST®
fused cast basalt. According to Nipsco piping supervisors,
the choice was made after a thorough investigation based on
the expectations for longevity, maintenance cost and cost
Prior to the commissioning of Unit 17, Nipsco
purchased 11,000 of ABRESIST pipe in May of '81 and 17,000
more feet in January of '82. This new pipe system would handle
the ash from Units 14 and 15 as well as Unit 17 which would
come on line in 1983 and Unit 18 which would come on line
Six pipelines exit from a trench on the east
side of the building and run over 3,000 to the ash ponds.
A support and anchor design was used with expansion joints
located in the long runs. A total of 28,000 of pipe was used
to replace worn cast iron pipe on Units 14 and 15 and installed
on the new Units 17 and 18.
The on-site piping contractor noted that the
installation of the new pipe went very smoothly. No leaks
were found in the test run. After 12 years of steady use,
a thorough inspection performed by outside piping maintenance
personnel confirmed that the ABRESIST pipes are living up
to Nipsco's expectations. The special telescoping expansion
joints have performed perfectly and none of the fittings have
needed to be replaced to this date.
Since the original orders, more of the
original cast iron and ceramic lined fiberglass pipes have
been replaced with ABRESIST pipe. The utility anticipates
that when the entire ash removal system has been retrofitted,
the cost of rotating and replacing ash piping will be virtually