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Unit 6 Cavitation Repair at Mark Wilmer PP
Thomas W. McCannMay 7, 2015
MWPP Unit 6 Cavitation Repair
• Current impeller went into service in 2008
• Cavitation repairs performed in 2011 and 2014
• During NGS maintenance outage this March, while
Unit 6 was dewatered for work on suction tube
scaffolding, crews observed significant cavitation
damage to impeller
• Maintenance crews worked 4 weeks, often 7 days
a week, to repair and return unit to service
– Combined effort by plant mechanics, heavy overhaul
groups, machine shop and protective coatings
Agenda Number 11.
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MWPP Impeller
MWPP Impeller
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MWPP Impeller
Confined Space
4
Cavitation Damage
Vane #1
Vane #2
Cavitation Damage
Vane #3
Vane #4
5
Cavitation Damage
Vane #5
Vane #6
Cavitation Damage
Vane #7
Vane #8
Vane #9
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Cavitation Repair
Cavitation Repair
7
Cavitation Repair
Cavitation Repair
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Cavitation Repair
Repairs Completed
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Repairs Completed
Repairs Completed
10
Questions?
