Coupler Strengths??
John LEE
I was wondering if anyone could help me out. I have heard that UP's Big Boy could start and pull a 5 mile coal train. I thought that was amazing and the first thought that came to mind was, could the couplers hold?? Even if the statement about Big Boyu's power is false i would like more information about the knuckles. if anyone has facts on knuckle strengths or a link containing them, please respond. this question has been puzzling me since i heard about the 5 mile coal train.
Benjie Lee
Ben1...@aol.com
thanx
tandrirwin
That was a PR stunt in a level yard.
They showed it on one of the older Pentrex
SP tapes.
300,000 lbs breaking point comes to mind.
It is cheeper to replace a knuckle than to
replace a ripped apart car.
Tim
CNW/UP/MRL
Charles E.Piercy
Some interesting numbers of steam engine capabilities at
http://www.steamlocomotive.com/misc/largest.html
As you have noted about couplers, when you see these comparisons, it is
utterly amazing just what was done with steam engines!
Ted
Roger L. Traviss
"Charles E.Piercy" wrote:
> John LEE wrote:
> >
> > hey
> > I was wondering if anyone could help me out. I have heard that
> > UP's Big Boy could start and pull a 5 mile coal train. I thought that
> > was amazing and the first thought that came to mind was, could the
> > couplers hold?? Even if the statement about Big Boyu's power is
> > false i would like more information about the knuckles. if anyone
> > has facts on knuckle strengths or a link containing them, please
> > respond. this question has been puzzling me since i heard about the 5
> > mile coal train.
All the couplers don't take all the weight of the train at the same time.
Train dynamics comes into to play.
The loco starts and takes the slack on the first car which starts to roll.
That car then adds its inirtia to the second car which then adds its inertia
to third car, fourth car. fifth car and so on down the length of the train.
When enough cars are rolling, they also assist in pulling the cars behind
them. Thus, the locomotive and it's coupler never has the full weight of
the train on its draw bar and neither does anyone car in the train.
That's why a coupler with a breaking force of 300,000lbs (As mentioned in
another post) can be on the head end of a 10,000 ton train and not break,
because it's never actually pulling all 10,000 tons.
Cheers
Roger T.
Clark Martin
<roge...@islandnet.com> wrote:
The only way an engine could be pulling the total weight of the train is
on a vertical "grade". Don't confuse tractive effort and weight.
Cars don't assist in pulling the train. Once the slack runs out, the
engine is pulling the entire train. The engine (assuming no helpers) is
providing all the pulling power so the maximum tension occurs in the
coupler between the engine and the first car.
While pulling a train, the tractive effort does four things. First it
over comes the static friction. I must do this to start the train (or
individual cars) rolling. Second it must maintain the pull against the
dynamic friction of the cars. This includes air resistance, bearing
friction and plastic deformation of the the rail and wheel. Third it
pulls the train up a grade. Fourth it accelerates the train up to speed.
On level ground, once the train is at speed, the engine only has to
maintain enough tractive effort to match the frictional drag.
A 10,000 ton train weighs 10,000 tons but it doesn't require 10,000 tons
of tractive effort to move it.
The maximum possible tension applied on the coupler is the total tractive
effort of the engine(s), again assuming no helpers. The tractive effort
of a given engine is dependent on the weight on the drivers and the
coefficient of static friction of steel on steel (including the effects of
sanding when applied). 300,000 pounds sounds about right. That would
probably be in excess of the maximum tractive effort of any single
engine.
A modern 6 axle diesel weighs around 180 tons and has a maximum
coefficient of friction (with wheel slip control and sanding) of around
.33. This yields a maximum tractive effort of 60 tons or 120,000
pounds.
There was an article in Trains (I think) about a line in the mid-west
where shortly after a train left the yard it had to run up a fairly steep
grade. The railroad didn't want to add helpers there so they put up to
ten 6 axle engines on the head end. Breaking couplers was so common on
this grade that they installed storage racks with couplers along the way.
The figure I recall from the article was 500,000 pound for the couplers.
These were heavy duty couplers. There is a letter designation applied to
couplers which indicates there capacity and usage (freight vs passenger).
--
Clark Martin
Redwood City, CA, USA
Macintosh / Internet Consulting
cma...@pacbell.net
"I'm a designated driver on the Information Super Highway"
John Garrison
Clark Martin <cla...@pacbell.net> wrote in message
news:clarkm-0206...@eagle.martin.home...
I can't vouch for what constitutes a good passenger coupler but there are
two classes which are in use on freight cars E60 and F51. They will mate
with each other but an E will not fit in and F drawhead and vice versa. Just
form personal experience the F coupler is marginally stronger. The main
difference is not one of strength but of who designed them. They are treated
as equals except that you have to have one of each at least on your engine
because they both break and they are not interchangeable as I said.
Additionally without resorting to numbers, I am familar with territories
having such grades that the local timetable will restrict the number of
loaded coal cars to such and such without rear end power; and will restrict
the total amount of head end power owing to the likelihood of having
sufficient power to rip the train in two while climbing. Power restrictions
are stated as a number of powered axles with old EMD and GE 4 axle engines
establishing a baseline. I.E. Engines of class wizbang99000/AC with 6 axles
is equivalent to 8 standard axles, unless coupled to a wizbang890000/DC in
which case it is equal to six standard axles. Since the AC and the DC won't
tlak to each other in MU mode, the AC reverts to DC, and so on. Thats' just
fantasy of course but that's how they figure what goes and what doesn't all
for the sake of not pulling your train to pieces.
Noel Stoutenburg
> <snip>...The main difference [between E- and F- type couplers] is not one of
> strength but of who designed them.
I may be mistaken; it's been known to happen once or twice before, but IIRC, the
main difference between E and F type couplers is not who designed them, but how
they are designed. Specifically, F-type couplers are the standard couplers we
are all used to seeing on the end of box cars, covered hoppers, flat cars, etc.,
while E type couplers are the "shelf type" couplers seen on nearly all tank
cars, which were desiged to prevent puntures of the end of a tank car in the
event of a derailment. Because of several "spectacular" catastrophic
derailments, in the '60s and early '70s in which the end of a tank car was
punctured by the coupler of the leading or trailing car, these types of couplers
are, in fact required by the Federal Railroad Administration on certain classes
of tank cars. It seems to me that I remember reading the report of a National
Transportation Safety Board (or maybe a predecessor body) investigation of such
a derailment in Geogia, where an explosion blew the ruptured tank car a
significant distance from the scene of the derailment. The distance of about a
mile sticks in my mind, but I am not certain this is the same instance. It's
been a while since I worked on a railroad, folks. I am confident of the greater
part of the post, but have I switched my "E's" and "F's"; don't live close
enough to an active line to run down to check for myself.
James Robinson
>
> John Garrison wrote, in part:
>
> > strength but of who designed them.
>
> main difference between E and F type couplers is not who designed them, but how
> they are designed. Specifically, F-type couplers are the standard couplers we
> are all used to seeing on the end of box cars, covered hoppers, flat cars, etc.,
> while E type couplers are the "shelf type" couplers seen on nearly all tank
> cars, which were desiged to prevent puntures of the end of a tank car in the
> event of a derailment.
The E type coupler dates from about 1930, when it replaced the type D as
the approved coupler for freight cars. It is the common coupler seen on
most freight equipment. The F type coupler is the interlocking variety
that is seen on many locomotives and some types of freight cars. H type
tight lock couplers are common on passenger equipment. The double shelf
type of coupler that is used on some types of tank cars is a more recent
innovation.
> It's been a while since I worked on a railroad, folks. I am confident of the
> greater part of the post, but have I switched my "E's" and "F's"; don't
> live close enough to an active line to run down to check for myself.
Yep, isn't it the way that always works? When one isn't sure, and
there's a 50-50 chance, you will most likely get it wrong. Must be some
type of law.
John Garrison
James Robinson <NOS...@ERIE.NET> wrote in message
news:3759E2...@ERIE.NET...
> Noel Stoutenburg wrote:
> >
> > John Garrison wrote, in part:
> >
one of
> > > strength but of who designed them.
> >
Murphy's law to be precise! Anyway the single and double shelf couplers come
in both E and F knuckle varieties, however the vast majority are the F type.
I have never bee able to ascertain that an E or and F is used on certain
equipment exclusively, excpet that most Engines do have the F knuckles. On
freight cars it seems a matter of what the car owner specified that it have.
(Shelved couplers of course being required for certain cartypes.)
TyShef
know through teaching and learning both at work and on my own time, Most
freight cars are equiped with the E knuckles and drawbars. The F knuckles and
drawbars are mostly used on unit train type cars. I.E. coal cars, new grain
hoppers, most intermodal cars, Molten Sulfer tanks, and coil steel cars.
According to our books the F knuckles are rated at a greater breakage rating
than the E knuckles. As far as locomotives, alot of the old BN SD40-2s and
others that were assigned to the coal trains are equipped with F knuckles, and
the rest are equipped with E knuckles. As far as the new units, the MACs are
equipped with F knuckles and i am not sure if all the Dash 9s are or not. Also
as previously stated the single and double shelf type couplers come in both E
and F type drawbars. Hope this helps
Tyson
5Ty
BNSF Conductor, Amarillo Division
Living Life Like A Runaway Train,
Run 8 and No Brakes
Jeff Silverman
Supposing you break a coupler while you are in the middle of a run. Now what do you do?
How much does a coupler weigh? Is it light enough for one or two men (or people) to
lift it?
--
Jeff Silverman, PC guy, Linux wannabe, Java wannabe, Software engineer, husband, father etc.
jeff...@oz.net
Travellin' Man
what do you do?
>How much does a coupler weigh? Is it light enough for one or two men (or
people) to
>lift it?
I'd say a knuckle weighs about 80 lbs or so??? I never actually weighed
one. I have walked one a mile and a half back on a train before, and 'twas
no picnic though it can be done. Usually a cooperative dispatcher will let
you split your train to get back to get it fixed when possible. When I was
a kid I used to make a few bucks by riding a knuckle back to the break on
my bike....
--
James 'gord' Gamble... the travellin' man
ICQ #36957838
CN Rail Engineering
John Garrison
Travellin' Man <bel...@auracom.com> wrote in message
news:01beb24c$8453dde0$4b879aa5@new...
or brakeman walks to the break and verfies the condition. Radios engineer
what kind of knuckle he needs. Enigneer tosses one on the ground along with
a lit fusee and some others fusees, and an assortment of tools. The trainmen
radios that he is on the rear and the enigneer will pull ahead, stopping
when the trainman sees the fusee. Trainman puts everything on the rear car
and lights a fresh fusee putting it on the ground (in case radio
communication gets lacking), and calls for the enigneer to back up to rest
of the train. Trainman makes repairs, couples train, quickie brake test, and
walks back to the head end. Of course the dispatcher has given protection
for all the moves; and almost always will to help speed things up and get a
line moving again.
Douglas Smith
Jeff Silverman wrote:
> Supposing you break a coupler while you are in the middle of a run. Now what do you do?
> How much does a coupler weigh? Is it light enough for one or two men (or people) to
> lift it?
And Smitty replies:
If you only broke the knuckle, that's what you replace, but if you broke the drawbar or
broke or lost an associated piece (carrier key, etc.), you wait for the carmen to come with
their truck to fix it. Generally speaking, if you can, you set the car out at the nearest
siding, inform the dispatcher of its location, recouple to your train and continue on your way.
Steve Everley
> Supposing you break a coupler while you are in the middle
of a run.
> Now what do you do?
Pray a lot...GBG
After praying you go over to the storage bin on the
locomotive and HOPE that you have a spare around. Most of
the LOCO's I have been on carry several, most of the common
styles. Well lets put it this way they are "supposed" to
have them on board. But if you desperately need one and the
LOCO does not have the spare of the type you need then....
walk to the rear of the train and hope the last car has the
kind you need on its rear coupler, since the rear coupler
most likely only has a FRED connected to it.. OTHERWISE BE
PREPARED TO SUFFER THE CONCENQUESES OF " delivering only
half your load to the next drop off point. " OR if you
happen to be near other parked cars, stealing one is not out
of the question but not really kosher in the rule book as an
alternative.
An Engineer could loose pay or even be suspended for a short
time, or get POINTs against his record for not checking to
see if spares are available "before" his trip and "he has a
breakdown".
> How much does a coupler weigh? Is it light enough for
one or two men
> (or people) to lift it?
Someone said about 80 pounds which is about right, however
it weighs 80 lbs. when you leave the locomotive, it weighs
about 160 by the time you get to the break...
-=Steve Everley=-
JStry32946
>it weighs 80 lbs. when you leave the locomotive, it weighs
>about 160 by the time you get to the break...
>
All the trainmen I've seen walk the train back to the break, radio the engineer
what knuckle it is and have them drop it on the ground, pull the train forward
and put the thing on the car back it back together and walk back to the head
end. I haven't seen them carry the stuff in years.
That doesn't mean the job ain't hard. One guy doing what should take two to do,
but.........
T.Berrum
Without a Brkmn its is very hard to Safely replace a knuckle by yourself.
Most of the pinlifters will not stay up there for I set the car out. bnsf
has a new policy that if the air hose comes apart you set out both cars for
inspection by the carmen-wheel truck.
>Supposing you break a coupler while you are in the middle of a run. Now
what do you do?
>How much does a coupler weigh? Is it light enough for one or two men (or
people) to
>lift it?
>
>