New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1890-10-29
POPULAR OBSERVATIONS.
WHEN AND WHY AIR BRAKES FAIL
pp.cr,CAI. POINTS BY A PRACTICAL MAN

PRACTICAL POINTS BY A PRACTICAL MAN.
To the Editor of The Tribune
Sir: On account of my absence have Just hoteo
the letter of Mr. "A sinclair the subject OF hepu'eu
Failure Of Air Brakes" published III your ''N"' VI
August 81 Having had quite an extensive Ca
with the use OF air brakes, am familiar VIII" 'o"o
facts In connection with the subject VINO" ""H "o'
change the claim made by Mr.. sinclair out may ''''"
some Light on the reason why air brakes may app"'-
emily he In p-oper order and yet fail TO stop TRAM
". Manufacture car wheels. The proper ana I'M
proper use brakes + important FACTOR III inc ~
OF wheels therefore study the subject !io" nuN
meas point of view, but the results eoou VI ~ ~
human life as well merchandise. A' ru'' no p"'O
Of the mechanism car receives more constant VI
c,robl attention than the air-brakc ATTACHMENTS
nroner and A. Mr. sinclair says, 'theV cannon id'i
without stopping the train,' proNialns .e p"l' '''
onara.s are also proper conhitloh. "'''o"' '"'o'
ing into technical explanation OF the SUBJECT may
h. said briefly that the brakes are applico o"e '
Medium OF rod connections, levers. etc., operated DN
a.. .i- b,aLe mechanism. When the brakes are app1"
air is admitted into the aircYlndcr uno'r
each car the piston i moved forward by the pressure
the motion IS communicated through IN" rodN IeNer
ETC forming the brake connexions. "l'' wv
brake. shoes are applied to the wheels Inc air press
nre used IS about seventy pounds to the square
inch II * manifest that this power subdivdcd ana
nn,ios through eight or brakeshoeS, would not
he sufficient 10 stop train under hcad"aE' III.
mower is increased by means of levers III Tue "su
mechanical manner with the usual result un"' '
movement at the outer ends of the rods anu Ht''?
= at the 1rake->hOc>. is very much less 'h'ii " -
NJ the pont tine power is applied, l. e. u' "
cv,trdor some years ago air cylinders were h'""c
twelve inches long but lately this has been ihc'e"''"
~ fourteen inches: the greater number III ",o "
twelve inches long. When the ar pfcN>"'o - "r
plied TO the cylinder. the piston head Is NOW" Nv"
ircbss To obtain thc increase in power require" "
"'i ara,. 1 q, one inch at the hrakeShocN thuN'
vb.p tho pi,t,u move, twelve inches. the br'heN"o
move one inch. If for anv cause the piston u'' ~.
ment or travel of twelve nchc. doeS ho 'pfH ,
brakes they cannot be applied by the a DRAM.
spism The latter may be in pcri'c oruri' ~. W.
Grafton of applying the brakes DC Pcri"''"'" t =,
design or accident, and yet the brakes VIII "o' :"
80 :. ,, ri.,o, travel is not properly anu
.a.c.velv communicated to the hrak"'Nhocs hr''
each car will be found from 80 I" % fcc' III '''V %
levers and connections referred To. l"N "t' M"
severe strain every time the brakes are aPp"'"' ""'
are constantly giving and stretching "''' ,h
vice The brakcshoe, arc rapidly worn out t'"""-"
f,,i ,,i,h ,hc v.noc;s when brakes are applied 10
,,rs nm This wear mean, provided for N'H'o'','o
the rods and levers. 1t is not possible 10 "'i'"'
total movement Of one inch at ea'h '""c' " .I
rca.on that cveh that small space TP'>'"'> ' ~,
amount available between the maximum 'rr m
opd ,hc greatest relaxation; three quarter, VI ~
inch is about all tial can S'''"
actual service. -, . ,r,Lc
when the connections are adjusted with ne" "'"",
shoes and everything in proper od'r' p'>u' I
of four inches will apply the bThc> ~ INV
wear ont or the connections give under s'l"'' W
., the nivotal points, the piston travel must nee
-, iaroa.o =, effectively apply the brakes. The
-or f brake. hoes j. rapid and the tht'h "hc''IN
travel Of the piston is more than eNhau>'eu !" ''
woarip. oct Of one brake shoe constant "'''"
must therefore he given to the connexions " -
t,,oy are Of proper length. and inspectors at '''""
nonts have this work in charge As rule the "o'"
c,ruot be done until trains are all maze up anu i''u
t,r denar;ure: the air pressure is then appIPn' tn
travel Of IN" piston watched. ana II u Is 'o' Er CIV
connecting rod, ~louli be shortened III ONer l''V Wv
brakes may be applied with les piston 'r"N'' anu d
margin Of safety provided TO allow lor ","'
ycry short time available for this work. the hurry anu
c,nf,sion incident - Tho departure Of trains ana '
prcs,urc TO gain every moment OF time III thS at' q"
,si".tr, and seconds serious o"StHIc' !" P'''
,o.i Irnancc If tho work; unfortunately '"'I'''
.1c at any other tine unless every ear Is 'aN'" ~
sou,, MONT provided with apparatus for E'aNiug d
tc IL practice almost impossible when tIo f'ca' mum
her Of cars IN service i considered - well a. the one
that drawing room and sleeping car are "'eh IL
service constantly for monta> al a tne ,., .,ou.
The report, Of tie Michigan Central Rallfcad snow
that 2,3I6 passed windsor ont, III w. ~.
iveivs inches: on such absolutely 40 braki"g
All {" hc"a were sleeping cars running through
f.: J., distant pants, tic mp IGN 49," car y" oi'n
att ichmc..', hcnc gwen by different T'H"'l I'm
Ig.uy.- IN transferring the ear across IN" fN'I
iron Dctro. 10 Wi4d,or aad wee versa tn@ wa,
alto led testing IL" piston travel ana Il Ic'OIu
IA 81. with thu above result. do not know "i any
otl"r railroad company makinE SYSTEMATIC recon- 81
IN kind During The lat year the Michi2'ih
hav. equipped tler with indicators. ope!d,Hls
automatically. hat show the exact conci'n Oh l'1n
travel al ali tiE.c>. When the Indicator l. uNco t
T'\funn, travel Of the piston l. always >hOwu and
tac necessary alteration +" t1ke up wear can o. inae
al any time From a careful Investigation OF the Hn
Zee, on many Of The leading railroads Of the tinted
ctat", and Canada. have no hesitation III rhSlns that
fan I'm
i 80 small a, TO be absolutely useless IN case IL IL
necessary 70 make sudden stop. Tor the causes gwen
above In cvrry-day practice it can readily b. seen
that I'm making the usual stops engineer can handle
his train without difficulty he khowI perfectly lhc
control he has over II, whether moderate pressure
will suffice or whether extra pressure must be used
The latter l., always davScroII>, through hahhnN 10
stop and slide wheels with entire los OF control hut
when danger cOnfr0nts HIN ana he must otia ic.i
thing for an Immediate and unexpected stop wei. w"
know they are not made. and that tn" diN"r-
ence of a few hundred feet ha, a terrible r'>nl IN
vestigat0n follows: II is sald that IN" ar hlahr'
failed 10 work. and that is the end OF IT, hrnly
believe IL the attachments through which tn" ar
brake does its work were Away. IN proper cSditi0n
accidents from this would be very iai'.
The conditions Of service above explained are IN no
way attributable to feature OF air brake co>trnc'
ton or application. The manufacturers OF air brakes
have been indefstigablc IN their efforts 10 Improve
and perfect their devices. WithOu Their ldbors ii
would be absolutely impossible to r1in trains at the
speeds in practice to-day. IL Is only Just 10 mem
therefore. that accidents commonly attributed TO
they belong and that effort he mad" on the part
Of railroad managers to supplement tho valuable ap
p!iancos now obtanabr with every safeguard that
can be found for their effective use -
President New York Cnr-whecl Works.
Buffalo. y y, oct. 20. lS90.
IT vr.sr pt EIGHT REC AI'SE IT'S ENGLISH