Thread: Boiler build
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Old 25-01-2007   #8 (permalink)
kevingambrell
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Hi
just as a starting point I thougt i would show the formula for working out the boiler plate thicknes.

P= Dx W.P. x F
__________
Sx2xRxCxT

Where P = plate thicknes (barrel) in inches
S = Ultimate tensile strength in PSI (copper 25,000 PSI Steel 60,000 PSI)
F = Factor of safety from 6-10 as a rule 8
R = riveting allowance (.8 for welded brazed or silver soldered)
D = Diameter of barrel in inches
C = corrosion allowance (for steel only .25 inch and bellow .5 to .8)
temperature allowance (copper at 400F =.7 200F = .87)
W.P. = working pressure

All flat surfaces should be atleast 1/3 thicker than the boiler barrel. Stays should not exceed a pitch = to

tx800
_____
W.P.

t = thicknes of inner firebox wrapper

Firebox stays should be twice the thicknes of the inner firebox wrapper.



Kevin
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