Posted by: Rolly
Nice job Pat your right on the money with the .015.
If some one wants to play with the math they can check me on this. I took an expansion coefficient of 9.4 for copper and 7.3 for steel, at a temperature of 500 F
With a boiler of 14 inch’s tall, the total difference between the steel outer pipe and the copper tube will be .0268 Saturated steam or water temp at 600 PSI is around 486F
The outer shell is insulated and the tube’s may see a bit higher temp in the tube but the inside water temp should be more of the constant.
The bottom sheet will go down the same as the top sheet will go up so split the difference and you only have .0134 inch’s on each end. About three sheets of copy paper.
Not much movement.