227
OF ENGINEERING FORMULÆ.
Break Experiments.
. (Royal Commission Railway Accidents, 1877. i
hvdrautic '?c?um = °> Westinghouse air; D. Clarke s
kt,rahJ'dniuilc. J’.W*; «. Steel Macluae»; H, Westing-
Weight of engine) A 0 1D E ! F 1 G I H
30-5 35-7 33- 35’7 25-1
empty ., tons J !29 • 6 33*45, 33
Do. tender, do. „ No. of carriages .. No. of break vans.. 12-05 13 2 114*7 13 14-5 13 14«’ I 13 14-5 10-f 13 13 16-Of 13 115-3 13
Weight of train) 248 260 2 j 2
loaded .. tons J Friction of vehicles) 207 200 ' 215 i 195 200 209
0-36
per cent, gross load f 0*35 0-45! — 0’33 0’46 0-25
Friction of engines ) and tenders .. J Retarding force, all 1 0-575 0-785 - — —• r
breaks in percent- 1 age of grcsa load 1 7'79 »•« 10-64 — 1 -64 7'60 7-33 5’88
with sand .. .. J Do. without sand .. Tenders and break) 6-21 5-72 10-04 8'31 6-47 5-75 4’94 5-26
vans only .. .. } Distance of stop at) 2-90 2-19 ” j 2-31 - - 2-35 2-03
60 miles per hour, 1 all breaks with [ sand .. .. feet 1 1540 1612 1128 , — 15721680 1640 2044
Do. Without saud „ | Time required to 7 1 1920 2100 1200 1448 1860 2088 2432 2284
put on break, secs, j If —— 5i 1 - — U
Do. to take off „ I — — * 1 — 1 81 | — | —
- — <J BeUUUQS.
Approximately a good continuous break will stop a train in mvuthir.1 ti
distance run when ordinary hand break» are use<t In „/hI* tho
experimental upon could the stopping be applied ta! snda«nf
Ihe break pressure should be taken off the moluout before th^
rest, in order to avoid sudden shocks. “*** train cornea to
°wil* “> «>« W><hty with which the
Wood and caflt iron do not appear to differ in skiddins power
bulance in yard» at which trains should bö canabl« <?, u?? i vi .
rent on the leve! = Ou V« when V = velocity in X Ä/r °Ugh‘ “*
V, Miles per hour. 30 35 40 45 w « en
rest
v, Miles per hour. 30 35 40 ' is' V,n ss
Stop m yards .. 99 135 176 223 276 833
■ Q 2
60
396