Two shift operation power plants

Power stations that were originally designed for base load applications are now increasingly
being asked to operate on a two shift, stop start regime; this is more commonly known in the
industry as dual shifting. The multiple start/stops that these stations are now experiencing is in
some instances causing an increase of operational issues due to the to the constantly changing
process parameters. For example dual shift stations will experience additional thermal stress in
the headers, drums, high temperature piping, valves plus the auxiliary equipment leading to
additional wear and tear of their systems and component parts. This is due to the more frequent
use of the plant at severe service conditions. The consequences of the change in plant operation
cannot be ignored. If the plant is not operated correctly or more importantly modified properly to
handle these changes the lifetime of the components within the plant will decrease enormously.
The changing operational requirements of the plant require that the steam coolers, desuperheater
valves, drains, feed water control valves, main steam isolation valves and the turbine
quick closing valves are reviewed. These critical pieces of equipment...
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