466
Molesworth’s pocket-book
Cornish and Lancashire Boilers. (Hayrez.)
I) — Diameter of boiler in inches.
d = Diameter of flues in inches.
L — Length of shell of boiler in feet.
I = Length of fire-grate in inches.
H = Nominal horse-power at 16’9 square feet per HP.
p = Effective pressure in atmospheres.
W = Total weight of boiler in lbs.
In Cornish boilers—•
Space between under side of flue and shell 4 to 6 inches.
Depth of water over flue .. .. .. .. 4 to 8 „
Cornish Boilers.
Lancashire Boilers.
I) = 1 • 7 d for Cornish boilers; = 2 • 5 d for Lancashire.
D = ll-42VlT; D = 11-4V*H.
d = 6-72Vl{; <Z = 4-56VH.
Z = 11-sVH; Z = 8-65<H.
L = 5-lVlI; L = 14-4 + 0-46 H.
VV = H(I10 + 22J> VH); W = H(220 + 12-352>VH).
Area of chimney, 15i square inches per horse-power.
10
20
30
40
50
60
Cornish Boilers.
Lancashire Boilers.
Dia- I Dia- Length Weight
meter . meter J of ■ of
of Shell, of Flue. Boiler. I Boiler.
inches.
36
51
62i
12$
80f
88f
inches.
214
30
36f
42i
4U
52
feet.
16-1
22-8
28
32’3
36
39-5
tons.
2-04
5-37
9-54
14-39
19'82
25-77
Dia-
meterof
Boiler.
inches.
62i
72
80|
88i
j Dia- i Length
i meter ■ of j
■of Flue. Boiler.
inches.
25
2Sf
32*
34 i
feet.
28-2
32-8
i 37-4
42
Weight
of
Boiler.
tons.
7-48
10'90
) 14"66
18'72
Pressure assumed at 5 atmospheres effective or 6 atmo-
spheres absolute.