EthosEnergy has completed a full inspection, repairs, testing and reassembly of a Westinghouse boiler feed pump turbine for Coyote Station, bringing the unit located near Beulah, North Dakota back to full load.
Coyote Station is operated by Otter Tail Power Co. headquartered in Fergus Falls, Minnesota.
The Coyote Station boiler feed pump turbine experienced an overspeed event that resulted in a failure of the steam path and severe damage to the casing and bearing brackets.
EthosEnergy provided an alternative solution to replace the steam path with a modern design that has enhanced thermodynamic performance and ease of maintenance, which allowed Coyote Station to get back to full load sooner than if they were to purchase a new turbine assembly.
Brad Zimmerman, Coyote Station Plant Manager said, “When we awarded EthosEnergy the work, we knew their solution had an added value element, in that they wouldn’t just repair the unit but improve performance and efficiency through use of modern manufacturing techniques. The efficiency improvement was projected to be around 3 percent however, we are now getting closer to 7 percent – 8 percent improvement out of the boiler feed pump turbine.”
Jason Barger, Regional Sales Manager for Power Plant Services of EthosEnergy said, “Our aim with customers is to always deliver added value to a project, no matter how big or small. With Coyote Station we were able to not only repair the unit but find innovative ways to re-engineer parts in order to make it run more efficiently.
By completing all repair work for them using our in-house expertise and facilities we were also able to have the unit installed, tested and working to schedule, saving them money by decreasing the time the main deck turbine had to operate at half load.”
EthosEnergy’s solution was to manufacture a new modern designed rotor, blades, diaphragms and repairing the nozzles, valves and bearings. In addition a full casing overhaul was employed to straighten and realign back to specification. Following shop repairs, the boiler feed pump turbine was returned to the Coyote Station where EthosEnergy provided full non-destructive testing, sole plate regrouting, alignment and reassembly.