326 APPLIED MECHANICS 
shaft and armature of dynamo, 87,638 Ibs. Moment of inertia of all rotating 
parts (units in lbs. and feet), 62, 654, 
Weight of reciprocating parts, including one piston, cross-head pin, and 
equivalent part for one connecting-rod, 2080 lbs. 
Indicator diagrams are given in Fig. 508. 
(1) Re-draw and enlarge the indicator diagrams, making the length of each, 
say, 4 inches, and take for the pressure scale, say, 1 inch to 80 lbs. per square 
inch. 
(2) Reconstruct the enlarged indicator diagram of the “‘A” cylinder on a 
four-stroke base, and add the inertia force curves, as shown at (a), Fig. 509. 
(3) From (2) construct the indicator diagram corrected for inertia forces, as 
shown at (b), Fig. 509. 
(4) Do the same as in (2) and (3) for the indicator diagram of the ““B” 
cylinder, but observe that the diagram of the ‘‘ B” cylinder must be moved one 
stroke forward in advance of that of the ‘“‘A” cylinder, since the explosion 
in the ‘“‘B” cylinder takes place one stroke in advance of that in the “A” 
cylinder. 
(5) Construct, on a base of equal angles of crank motion, the combined 
7—7 250 
5 \ 
s | f\ 
aya %+200 —— L 
‘A’ Cylinder. RS B’ Cylinder. 
\ 3 7) 
ic ae) & , 150 
‘ 5 
\ » Sb100 
N 8 ‘ 
~ - N 
Be ; a 50 Bar AE 
N at x 
i ee Ss = Hilt 
ia ia kee So TL ie] ————— = 
Fig. 508. 
250 
: | 
200 Fx — 
_—Lndicalor diagram. 
4 i (a) 
100 SE — 
= sone _— Inertia forces. r 
0 = Tg ais Cah <2 es nth ane 
-50.<— ade , Bsa 
Bakes One revolution.--- —«—-—-- One revolutiom. -=-— 
sof wa l diagram 
\ Indicato (2.) 
corrected for inertia forces. 
aie te ph eel 
