Chip,
The change you are proposing has several implications for the plant operations.....
I assume that you are talking about LP heaters located in a steam surface condenser in a thermal power plant.
LP heaters are located in the "neck" of the condenser for a couple of (1) space savings in plant layout (2) pressure drop savings on the shellside. Typically, LP heaters have a shellside steam temperature only a little above the condenser temperature. Usually there is little to be gained by insulation.
What you are proposing is an "improvement" on the original plant design......
Insulating the LP heaters runs the risk of:
- disrupting the steam flow beneath the turbine and creating additional backpressure
- having the insulation break off and damage the condenser tubes
Please give us more specific about your installation
Just my thoughts & opinions.....
MJC
Have you considered these