\fdO'^ - Old Forge Coal Mines

228 STRENGTH OF MATERIALS.
(604) Using formula 87,
*
12,000
^
12,000
(605) The radius r of the gear-wheel is 24' Using
formula 80, ^=c {TPr = . 297 f350 x 24 = 2. 84'. Ans.
(606) Area of cylinder = .7854 x 12' =113.1 sq. in.
Total pressure on the head = 113.1 X 90 = 10,179 lb.
Pressures on each bolt = — ^^ = 1,017.9 lb.
Using formula 65,
F= A S, or A=^=
/* 1 017 9
'
:!^ = .5089 sq. in., area of bolt.
.5089
'
Diameter of bolt = |/ = .8", nearly. Ans.
(607) (a) The graphic solution is clearly shown in Fig.
53. On the vertical through JF., the equal loads F^ and F^
1 Ton. . 1 Ton,
CB IS'— ^
Scale of forces 1=2000 lb.
Scale of distance 1^6^
Fio. 53.
are laid off to scale, 0-1 representing F^ and 1-2 representing