It honestly never occurred to me that a crew would try turning retainers ‘on the fly’. Would they do a 15# set and then have the head brakeman dismount and run alongside the train turning retainers as it passed him?
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In the steam era, the retaining valve was near the hand brake at the top of the car. The brakeman would walk the top to set retainers.
Jeff
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“In the 20th Century with steam power in graded territories TTSI would require some percent of the train - starting from the engine to have the Retainer valve used -”
EL Scranton Div timetable in 1961 said to set retainers, starting with the second car. Never seen that on other RRs – why not set the first car?
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B&O Cumberland Division employee TT from 1963
13 OPERATION OF AIR BRAKES
The standard brake pipe pressure for freight service is
80 pounds, except where Special Instructions provide for a
higher pressure. Engines charging the brake system on
cars to be placed on rear will carry 65 pounds of brake pipe
pressure to avoid over-charging car brakes. Rule 14, Form
1118-D-Rev. 4 modified.
After the brake system on a freight train is charged to
within 15 pounds of the setting of the feed valve on the
Iocomotive, but to not less than 65 pounds, as indicated by
an accurate gauge at the rear end of train, and upon13 OPERATION OF AIR BRAKES
receiving signal to apply brakes for test, a 15 pound brake
nine service reduction "must be made'and brake valve
iabped. Brake pipe leakage must not exceed 5 pounds per
mi^nlute. After-Ieakage tlst is completed, engineer will
reduce brake pipe pressure to make full service ap-plication.
Inspection of-the irain brakes must be made to determine
thai angle cocks are properly positioned, that the brakes
are applied on each car, lhat piston travel_ is co-r"rect, that
brake iigging does not bind or foul and that q[-parts-of
the bralie equipment are properly secured. When this
inspection ha! 6een complet-ed, the release signal must be
giv'en, brakes released and each brake inspected to see that
all have released. Rule 208(a), Form 1118-D-Rev. 4
modified.
Terminal test of air brakes will be made on freight trains
when air gauge on rear indicates a pressure of 65 pounds.
Engineer willset red hand over black hand on brak_e pipe
flow indicator. It is not necessary that amber light be out
when terminal test is made. Brake pipe leakage must not
exceed 5 pounds per minute, Rule 200, Form 1118-D-Rev.4
modified.
When trains stop on descending grades and Flagman is
recalled, proceed signal wiII not be given until brake pipe
is properly charged.
When necessary to set cars off on grade, air brakes will
be applied, hand'brakes set on all Cars, then air brakes
released.
Engineer requesting assistance on line of road will take
charge of lead engine and handle air.
Regular sections of trains designated "The Chicagoan"
and "The New Yorker" will carry 90 pounds brake pipe
pressure.
Not less than 25 retainers, in high pressure position, or
as many more as the Engineer may deem necessary will
be set on head end of Eastward tonnage trains before descending
Nine Mile Grade, and, short cycle method of
braking will be used. Unless otherwise instructed, Eastward
tonnage trains requiring use of retainers descending
Nine Mile Grade will stop West of Stewart Crossing to
turn up retainers and get Helper. Retainers on Eastward
tonnage trains descending Nine Mile Grade will not be
turned down until train clears at Weverton unless necessary
to stop after passing Eastward approach signal
Harpers Ferry.
Retainers will not be used on Eastward tonnage trains
on Patterson Creek Sub-division when dynamic brake is
operative. If dynamic brake is inoperative, or Diesel locomotive
is not equipped with dynamic brake, not less than 25
retainers in high pressure position, or as many more as the
Engineer may deem necessary, will be set on head end.
Dynamic brake will be used to assist in controlling speed
of passenger trains descending Seventeen Mile, Cranberry,
Cheat River and Newburg Grades. Dynamic brake will
not be applied until automatic brake has been set with
reductions totaling at least ten (10) pounds. Dynamic
brake must not be released unless automatic brakes are set.
In applying and releasing dynamic brake, extreme care
musf be used to avoid harsh slack action. Rule 4(b), Form
1118-D-Rev 4, modified.
At Fairmont and Grafton, Eastward tonnage, local, pickup
and work trains will be prepared for power brake
operation and will be handled by power brake operation
descending Cheat River and Seventeen MiIe Grades. Retainer
valve test wiII be made on such trains before leaving
Fairmont or Grafton. Train crew is relieved of making
retainer valve test before leaving Fairmont or Grafton
when such test has been made by carmen.
Eastward and Westward fast freight, Westward tonnage,
local, pick-up and work trains will be handled by
pou'er brake operation descending Seventeen Mile, Cranberry,
Cheat River and Newburg Grades. Retainer valve
test will not be necessary on such trains. Terminal air
brake test and road test prescribed by the rules must be
given these trains.
Trains picked up on line of road, or dispatched from
terminal or assembling point where air line is not provided
for testing air brakes, wiII be retainer tested by engine -and train crew at some convenient point before descending
grade.
On Seventeen Miie, Cranberry, Cheat River and Newburg
Grades the standald air pressure will be:
Loaded Trains.
Main Reservoir ... ..130 Pounds
Brake Pipe .. 90 Pounds
Empty Trains.
Main reservoir . .'. . .130 Pounds
Brake pipe .. 80 Pounds
Westward loaded trains will carry 90 pounds brake pipe
pressure between Oakland and Grafton.
Eastward loaded trains will carry 90 pounds brake pipe
pressure between Newburg and final terminal.
Eastward loaded trains will not be required to stop at
Blaser or Altamont to test brakes provi-led the required
minimum brake pipe pressure of 80 pounds is shown on
caboose guage.
Following instructions will govern handling of retainers
descending grades on West End Sub-Division:
A11 retainers which are to be used will be placed in holding
position before descending grade.
Seventeen Mile and Cheat River Grades.
High pressure position on all loaded cars and low pressure
positionon all empty cars, except 5 rear cars in
train.
Retainer valves will be turned down on Eastward
trains at MK Tower, on Cheat River Grade, and
after passing Bloomington, on Seventeen MiIe Grade'
Cranberry and Newburg Grades.
High pressure position on all loaded cars.
Low pressure position on 50 per cent, of all empty
cars beginning with car nearest to engine.
Retainer valves will not be turned down until Westward
trains have passed Signal 2507 or 2507F East
of McMillian on Cranberry Grade, and, Raccoon
Valley Junction on Newburg Grade.
SIow direct exhaust position on 50 per cent. of cars in
trains consisting entirely of empty open top cars,
beginning with car nearest to engine, retainers to
be set at originating terminal and turned down at
bottom of Newburg Grade.
When retainers are used on Time Saver Trains descending
Seventeen Mile, Cranberry, Cheat River and Newburg
Grades, a1I retainers will be turned up to slow direct exhaust
position before leaving Cumberland and Grafton and
turneddown before arrival in Grafton and Cumberland.
'When retainers are used, short cycle method of braking
will be used descending Seventeen Mile, Cranberry, Cheat
River and Newburg Grades.
TonnaEe trains, descending Seventeen Mile, Cranberry,
Cheat River and Newburg Grades, that stop for any
reason, will wait five minutes before attempting to
proceed.
Following instructions will govern handling of retainers
on M.&K. Sub-Division.
High pressure position on all loaded cars descending
grailes Eastward Manown to one mile West of King-
*ood, and, Kingwood to one mile East of Albright;
Westward Manown to Arthurdale Mine and Cascade
to Sabraton.
Low pressure position on two-thirds of gmpty cqrs
starting with car nearest engine, descending grades
Eastward Manown to one mile West of Kingwood,
and, Kingwood to one miie East of Albright; Westward
Manown to Arthurdale Mine, and, Cascade to
Sabraton.
Trainmen will not turn down retainers on these grades
until train arrives at bottom of grade.
Freight trains will make road test of air brakes before
descen<iing grades at Manown, Kingwood and Cascade.
Flat Maintaining Feature.
Freight trains handled with diesel engines equipped with
flat maintaining feature, which is cut in, dynamic brake
operative on a minimum of three units on tonnage trains,
two units on QD trains, providing units on which dynamic
brake is not operative be at all times next to train, and
engineer has been properly qualified on manip_ulatio-n.-of
flaT maintaining featur6, mhy be operated down-Nine Mile,
Seventeen Mile, Cranberry, Cheat River and Newburq
grades and grades on M&K Sub-Division without use of
retainers.
In descending heavy grades with flat maintaining cut in,
the initial reduction must not be less than 6 pounds (on
tonnage trains down Cheat River and Seventeen Mile
Gradei 8 pounds). The endeavor should be to control the
speed by irse of 'flat maintaining and the dynamie brake
s6 that it is uniform. If a train stops on descending grade,
sufficient number of hand brakes, starting at the engine,
must be applied promptly to secure it before air is r-eleased,
if the ind-efendeilt br;k6 on the engine will not hoid train
while brakes are being released and brake system recharged
or retainers turned up. Should train part, sufficient number
of hand brakes musf be applied promptly to anchor both
portions. A partial release of the brake during flat maintaining
musf never be attempted. If necessary to release
on deicending grade where retainers are otherwise required,
stop -will be made and brake system recharged
before train proceeds.
Otherwise, retainers as specified must be used.
This includes the territory from Grafton to Cumberland and on to Brunswick, MD
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A set retainer applies a 15-pound brake set and holds the brake cylinder pressure there. I think the idea is to have one relatively free-rolling car between engine and tender to preclude snatching a knuckle between a ‘set’ car and the mass of the relatively unbraked locomotive.
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Thanks. Here’s a post I saw on Trainorders.
“ All the K’s in Chama are setup with drifting throttles. Just a big high pressure ball valve in the cab that takes steam from the turret I believe and sends it to the superheater header.
The helpers use it all the time when descending from Cumbres to Chama all the time to let the tires cool a bit. They’ll throw the johnson bar in reverse and turn on the drifting throttle. The exhaust sounds strange when they do this. Sounds like a chopper.”
There is a wide and wonderful world of contrivances and practices regarding the most effective method of drifting, and of implementing counterpressure braking. Note that early Mallets were so eager to compression-brake on the LP engine when drifting that they were fitted with (fairly effective!) bypass valves – these are on 1309.
You are probably familiar with ‘snifting valves’ of various sorts including what’s behind that little pie-slice-reinforced plate on PRR steam. These admit air into cylinders being backdriven with the throttle closed, so hot gas and cinders don’t get sucked down the exhaust tract to ruin the tribology and the bore and ring finish.
The Swiss evolved methods of using clean air, for example from on top of the boiler, and sometimes pre-warming it, to use as vacuum-breaking on a closed throttle. This had the manifest disadvantage of having substantial oxygen content too. But it did not waste steam mass.
Normal practice for drifting was to valve a certain very small mass flow of steam into the chests (no more than about 15psig) which would displace any air, break any vacuum, and keep the cylinders warm against wall condensation. Since normal dome throttles are difficult to regulate accurately in that range, smart practice is to fit a drifting throttle, which is also useful in hostling and spotting if you are alert.
Now, if you have the drifting throttle open and the valve gear set to the reverse side of mid, the admitted steam mass will be compressed (and reheated) much as the mass of overcritical boiler water in the le Chatelier brake, after it flashes, is. The advantage of the drifting throttle is that it is fed from the steam space, so any TDS or boiler treatment chemicals don’t – at least they don’t in theory – wind up in the cylinders to cause confusion and delay. The price of the drifting throttle is that it increases steam mass flow even with the locomotive going downgrade, and with that added flow comes increased water rate, fuel burn, etc.
Thanks for the insights.
Now I recall how the train on Mt Washington descended. Loco in front and it was working hard. Yes they were using car brakes too but that loco wasn’t just along for the ride! Must have been along the lines you said.
I suspect, but don’t know, the primary braking force on the Mt. Washington Cog Railway would be primarily applied to the cog mechanism as it controls the motions against gravity. Brakes on car wheels and engine wheels would be assistance to the cog brake - On the steeper parts of the route I would be surprised if any form of wheel tread brakes could control the train without the benefit of the cog.
According to Wes Camp, the engine is equipped with a le Chatelier brake… but it only brakes the locomotive! On the way down, there is actually slack between the car and locomotive – the car doesn’t buffer up against the locomotive for ‘extra’ braking; the two are controlled separately.
As a peripheral note about the effectiveness of the ‘water’ vs. friction brakes, this from TrainOrders:
One of the reasons the Abt rack and some other systems were developed is that Sylvester Marsh’s system has the cograil teeth pointing straight up and the cog above it. Excessive momentum might tend to jack the car up and either derail it or cause the cog to come out of mesh… and yes, no tread friction would hold the car even with the wheels locked by effective ‘wheel braking’.
Note the Fell system, which has pairs of spring-loaded wheels clamping either side of the web of the traction rail. The head of the rail serves as a continuous brace against the wheels lifting out of contact.
From what I remembered riding the cog years ago (I could be wrong), the car isn’t even coupled to the engine. And the brakeman would ride the brakes down keeping the car pretty much against the engine.
I guess that way if the engine suffered a mechanical issue and ran away, it wouldn’t drag the coach with it.
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As usual, correct – but this is the context which the quote from TrainOrders references when he says there’s a communication line between the two so they’re not fully separated…
Interesting. Thank you!
I remember the same thing now that you mention it. I sat literally in the first row of the first car. Watched the whole process with much curiosity. Recommend it. Bring a jacket. Even in summer. It’s cold up there.
Also drove to the top too. When you go down a ranger walks up to each driver and makes them put the automatic tranny into low and tells them to leave it there to the bottom. When they saw my stick shift already in first they just nodded and said you’re fine.
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C&O ordered locos (GP7 era) for use in mountainous areas with dynamics. Those for use in "flat lands), ie, in the northern reaches, did not get dynamics.
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