A question about couplers....

[Anonymous]

Hello all, I had an interesting night last night as an NS freight train ahead of me on the Belt RR in Chicago went into emergency. The dispatcher gave us a signal that let us run down the track next to the train. We were only able to get by about five cars as we had a stop signal at Belt Junction, a very busy piece of RR. Anyway, I got off and walked from the rear of the train while the NS conductor walked from the head end. I walked up about 8 cars when I heard air blowing and saw about a 1 car gap. I figured it was a broken knuckle, but I checked both knuckles and they seemed fine. I called the NS crew and informed them of the situation. I then tied the NS train together and noticed one of the cars knuckle pins woud not drop. So I had the engineer stretch apart and I closed the "problem knuckle" and opened the other. I still could not get the pin to drop. We tried tying together again and the same thing. I noticed that the two knuckles seemed to be different. It was almost like the one knuckle was too wide for the other to completely grab onto it. By this time the NS conductor found me and I told him what was happening. He tried to same thing as myself and I explained to him my theory. He wasn't sure either. He finally just tied together with a little more force and the knuckles finally stayed together. The NS train pulled clear of the junction about 30 car lengths when it went into emergency again. By this time I was on my train and we were headed by it again and I verified that the same two cars came apart.
Does anyone know why the knuckles weren't staying together?? I never saw the one pin drop, but when the conductor stretched his tie the knuckles stayed together. I assuming once the NS train started to pick up a little speed the slightest bit of slack was able to force the knuckles to seperate. Does anyone know what the cause of this was???

[kenneo]

This is a bit wierd.

I know that new cars, because the new coupler parts have a bunch of rust and a very unsmooth surface on their working parts will have a hard time both coupling and uncoupling until the surfaces are worked smooth. but this is something else.

The only thing that comes to mind is that the wear parts have a large wear factor and are in need of replacement. But this is just a guess.

At any rate, I would hope that the NS crew would report both cars with bad/order couplers. One, at least, needs to be fixed.

[Anonymous]

Kenno,

That's exactly what the engineer asked me to do was report the two cars to him. I'm sure they had to call out a carman to fix it the second time the train came apart. Luckily this occured at about 2am and not during rush hour when the train would have been tying up busy Southwest Highway and blocking Metra trains from getting across the junction. I didn't mind helping because it gave me something to do because conductors simply don't do any work on piggy backs, at least at my terminal. Everything is done by the ramp.

[MP173]

Nate:

I know nothing about knuckles so I cant help you. I did watch the CN change a knuckle yesterday on a coal train that stalled and then broke apart. I didnt get too close, because I would imagine the last thing the crew would want is some stranger with a camera looking over their shoulder.

After the knuckle was repaired/replaced...whatever it is considered, the crews (two trains worth of 5 locomotives) had quite a task to get the train started and moving...smack in the face of a .88 grade on curves with a steady rain.

The train went forward about 1/2 carlength and I heard a BOOM. I figured ... yet another knuckle and another 1 hour tie up on a busy mainline. But no, after a five minute pause, the locomotives reved up and one unit, a UP was actually "bucking" or whatever, it was shaking madly.

Slowly the train began inching forward. And i do mean slowly. They slowly gained momentum and after about 1/2 block I timed how long it took a carlength to pass....it was 19 seconds. Still barely moving. However, the train got up and running, cut off the extra power and moved on.

The same scene was repeated a few hours later, this time with power from a following train pushing.

Now, for the question....what was the "BOOM" I heard on the initial startup?

Is it safe to assume the slow start was to keep a knuckle from breaking again? Is it normal in that situation to literally crawl when starting?

Why was the one unit "bucking" or visibly shaking?

All in all...a pretty good show. Gabe, you should have been here!

ed

[Anonymous]

If one knuckle seemed to be wider, it would also be my guess that there was excessive wear on the knuckle/coupler area, and it was time for a new piece.

Usually the carmen catch these kinds of things, but with the millions of pieces of equipment out there, there's always bound to be a few that slip through the cracks.

[Randy Stahl]

Were you trying to put an F knuckle where an E knuckle supposed to go?
Randy
never mind!

[mudchicken]

QUOTE: Originally posted by Randy Stahl

Were you trying to put an F knuckle where an E knuckle supposed to go?
Randy
never mind!

[(-D][(-D][(-D][swg][swg][swg][(-D][(-D][(-D]

[M636C]

QUOTE: Originally posted by Randy Stahl

Were you trying to put an F knuckle where an E knuckle supposed to go?
Randy
never mind!

Guys,

I was under the impression that AAR knuckles were interchangeable!

In Australia, we tend to use "Sharon Alliance" couplers which do have a different knuckle. When we got the GT46CWM units from London Ontario, we found they had "F" couplers, so they had to carry their own knuckles around in little boxes welded onto the pilot beam until they were all refitted with "Alliance" knuckles.

Peter

[ValleyX]

Yeah, slow start to get them stretched out and slow start because that's all he could do, he was probably holding his breath when that UP engine starting bucking, one wheel slip and KAPOWIE. The loud boom you heard, I don't know what that could have been.

[Randy Stahl]

QUOTE: Originally posted by M636C

QUOTE: Originally posted by Randy Stahl

Were you trying to put an F knuckle where an E knuckle supposed to go?
Randy
never mind!

Guys,

I was under the impression that AAR knuckles were interchangeable!

In Australia, we tend to use "Sharon Alliance" couplers which do have a different knuckle. When we got the GT46CWM units from London Ontario, we found they had "F" couplers, so they had to carry their own knuckles around in little boxes welded onto the pilot beam until they were all refitted with "Alliance" knuckles.

Peter

Nope... not interchangable
Randy

[Anonymous]

Why are there still 2 different kinds of knuckles?

[Anonymous]

The loud boom- I'm not an engineer or anything, so I'll need one to help me out here. I saw a training video for the SD70MAC, and there is some situation when, under heavy load, a traction motor or two cut out (I forget exactly why- I'll have to look at the video again). What I do remember is when that happened the whole locomotive jerked violently. From inside the cab you would have thought they collided with something. So severe was the jolt they made the point that when pulling near the limit everyone in the cab must be seated. Could something like that have occured?

[Randy Stahl]

QUOTE: Originally posted by macguy

Why are there still 2 different kinds of knuckles?

Because there are two styles of drawbars.
Randy

[Mookie]

QUOTE: Originally posted by Randy Stahl

QUOTE: Originally posted by macguy

Why are there still 2 different kinds of knuckles?

Because there are two styles of drawbars.
Randy

No, no, Randy! You aren't going to get off that easy. You will have to explain why two different styles of drawbars and on what cars are they used?

Mookie

[M636C]

In simple terms, the "E" type coupler is the standard model, and the "F" type has interlocking wedges and matching recesses to align the couplers vertically to prevent accidental separations in operation and to prevent "overriding", one car climbing over another in a collision or derailment. Passenger cars usually have "F" type couplers.

Peter

[MP173]

Fuzzy:

The boom I heard was not at the locomotives, but down the grade, where the cars were.

The more I think about it, the UP unit was more "violently shaking" rather than "bucking". It was never in any danger of tipping over, but it was vibrating quite well. The other units were not. Could it have been that unit might have had some sort of brakes on it's unit (is it called independent brake?)?

Anyway, it was quite a site and the crew did a hell of a job (in my nonrailroading opinion) to get the train started, with all power (probably about 19,000 hp) on the front end.

Interesting conversation between the dispatcher and the crew after the fact. Basically, the dsp asked if he had lined the train on the mainline 7 miles westward if he thought it would have made it. You have to understand the line goes from double track to single about 4 miles west of where the stalls occur.

"Would it have made a difference had I lined you up at Spring Lake rather than Sedley?" (This would have given him a little momentum, instead of slowing for the turnout)

There was actual conversation between the dispatcher and crew trying to figure out how to alleviate the problem.

"Nope, we need more horses." was the reply. Real simple answer. "Even a little engine would help."


Like I said, four hours the scene repeated itself again.



ed

[Randy Stahl]

QUOTE: Originally posted by M636C

In simple terms, the "E" type coupler is the standard model, and the "F" type has interlocking wedges and matching recesses to align the couplers vertically to prevent accidental separations in operation and to prevent "overriding", one car climbing over another in a collision or derailment. Passenger cars usually have "F" type couplers.

Peter

Exactly, the "F" coupler is used on tightlock or top shelf couplers. The "E" is used on almost everything else.
Were cool now mook?
Randy

[Overmod]

n_stephenson, was one of the two cars involved, by any chance, a tank car?

IIRC, there are FRA regs mandating anti-overriding shelves on at least some classes of hazardous-material-transporting cars. Would such couplers have the different F knuckles for tightlocks, and could (perhaps by some odd mischance) a knuckle for a different type of coupler be installed in one of those couplers by mistake to produce the result observed?

[edblysard]

What hasn't been pointed out is that they do, in fact, couple into each other, all of the knuckles will mate up with another coupler of a different design.

I think, based only on what was posted, that the drop lock, the part inside the coupler that locks the knuckle closed, was jammed or bent...I have seen them bent so badly you can't even get the knuckle in the coupler...if the pin will not drop, then there isnt much more that can be wrong, its really a simple design.

Ed

[Mookie]

QUOTE: Originally posted by Randy Stahl

QUOTE: Originally posted by M636C

In simple terms, the "E" type coupler is the standard model, and the "F" type has interlocking wedges and matching recesses to align the couplers vertically to prevent accidental separations in operation and to prevent "overriding", one car climbing over another in a collision or derailment. Passenger cars usually have "F" type couplers.

Peter

Exactly, the "F" coupler is used on tightlock or top shelf couplers. The "E" is used on almost everything else.
Were cool now mook?
Randy

Just a pair of icecubes, Randy!

[Anonymous]

Overmod,

Both of the cars were boxcars.

I was northbound on the UP again by 95th street when the dispatcher told us a train had gone into emergency. This was the second consecutive trip of this occurence. Right before we stopped at the problem area the conductor reported a broken knuckle. We pulled our engine up to the car with the broken knuckle. Somehow part of the knuckle was stuck in the housing and the pin could not be pushed up. We tried everything to get that broken piece of knuckle out of there, but to no avail. So, we ended up deciding that using a chain to tow the car would be the only alternative at the time. Someone suggested pulling the entire train back using the chain, which I thought was ludicrous. The broken knuckle was about 20 cars from the head-end in a 100 car train. I didn't think it was worth the risk of trying to pull all that trailing tonnage with a chain. My suggestion was to cut away with the broken knuckle car and take the head 20 back to Yard Center about 7 miles south, and then come back engine light and tie onto the rest of the train. The original plan was to have the one busted car set out at the yard and come back with the conductor riding the shove over about 15 road crossings in the South Side of Chicago!!! After we dropped off the chain and wished them luck we went further north and sat hours waiting to get called onto the Belt RR. We yarded our train just before hours of service expired and then waited three hours for a taxi. A nice long 16 1/2 hour day and to cap that off we get called at breakfast to deadhead home. NEED SLEEP.....[zzz][zzz] By the way I found out on the ride home that my engineer can saw logs better than Paul Bunyan!!!

[edblysard]

By chance, did the box with the "bad" knuckle has cushioned underframe?
It dosnt take much for those long drawbars to get floppy, and droop down, which hammers the heck out of the knuckle in switching, and often keeps them from aligning with other couplers.

Sometimes, you have to smack the crap out of them to get the pin to drop, because they hang so low.

Ed

[Anonymous]

Ed,

I was thinking the same thing you were and I asked the engineer to bring them in a little harder and still no success. The NS conductor even whaled on them harder and the couplers stayed together, but I let the conductor know that the pin did not drop, and of course he was haunted by it once again. At least the cars were able to stay together long enough to clear the busy junction.