501 OF engineering formitlæ.'
Appboximate Rüles fok the Proportions op
Locomotives.
Area of steam-ports..........
Area of eduction-port .. ..
Diameter of piston-rod .. ..
Diameter of feed-pump plunger
Diameter of feed-pipe .. ..
Diameter of valve-spindle ..
Diameter of outside crank-pin..
Length of „ „ ..
Diameter of boiler .. . . ..
Diameter of steam-pipe .. ..
Diameter of blast-pipe .. ..
Diameter of piston-rod .. ..
Thickness of pistou..........
Diaui. of connecting-rod ends ..
„ „ middle
Diameter of crank-axle .. ..
Length of journal of crank-axle
Capacity of tenders in gallons ..
Capacity of tanks of tank-)
engines, in gallons .. .. J
Heating surface..............
= D2 X -08.
= D2 X ' 18.
D
- -j. Dx-16.
- D X '12 if of the same
stroke as the engine.
- DX :12.
- D x '09.
- D X *26.
- D X '28.
= D X 3-11.
— L>- X 'O2.
— D X -3.
— D X -16.
— D x -28.
— D X -16.
— I)X -21.
— D X "4.
— I> X M3.
— D X 90.
— D X 60,
= 65 area of fire-grate.
Rule for the Lap and Lead of Locomotive Slide
T = Travel of slide in inches.
L = Lap of slide in inches.
I — Lead of slide in inches.
L =T X 0-22.
Z = Tx0-07.
Rule for the Strength of Locomotive Springs.
(D. K. Clark.)
S = Span of spring in inches.
B = Breadth of plates in inches.
T = Thickness of plates in sixteenths of an inch.
N = Number of plates.
I) — Deflection in inches per ton of load.
L = Safe loud on spring in tons.
T Bl’iN ,r 11-3SL _ -14S3
L =--------• N —----------------• T) =--------------•
11-3 S BT2 T3 B N