wheel. (I think)?
1: do the engines get flat wheels?
2: More, less or about the same as say a coal gon?
3: Would a defect detector be the one to pick it up?
4: When a defect detector finds a problem, who is notified?
5: Thank you.
Well, the trackside equipment that is best for detecting flat wheels is a “Wheel Impact Load Detector”, or “WILD” - a hotbox or dragging equipment detector obviously isn’t going to be much good for that.
I’m sure that there are other quite capable “non-technological” methods by which flat spots on locomotive wheels are also found and dealt with - but I’ll let others respond to that.
- PDN.
If a Loco has a Flat wheel the Crew will be screaming at the shopp that the loco is riding rougher than normal and also that the coffee cups will not stay in the cup holders anymore.
About 30 years ago a large eastern railroad had an SD-9 that was used around the clock to flat shift a yard. I guess the independent brake cylinder pressure was set up too high because it would stop a cut of cars on a dime, but it had so many flat spots it sounded like a machine gun. Somebody wrote “Old Squarewheels” on the long hood. It was a great engine for kicking cars but eventually it got sent to the shop to have the brake set right and the wheels turned. When it came back, it was a good shifter, but not a great one.
I’m sure they do, but this is more likely: http://csx-sucks.com/pictures/?burnim.jpg
Of course they do! Unless the engineer is numb in the butt and his ears are on a cell phone or Ipod or otherwise plugged, he doesn’t need a dector: he would hear and feel it the same way an NJT commuter feels it on his Comet ride! Er, no sarcasm intended. Much.
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Yes, as everyone so far has said.
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Probably fewer instances in a given train, but possibly more than for any one freight car. Nobody has complete control over flat spots on the cars, but the engine crew is very likely going to be blamed for literally sitting on the creation of a locomotive flat spot.
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As Paul said, you’d need a WILD detector if you were dependent on a detector for finding flat wheels on a locomotive. But the occupants are probably going to be the best detectors, either through hearing it or feeling it.
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The defect message is broadcast over the radio, where any crew within earshot, as well as the dispatcher, can hear it. Appropriate notification would proceed from there, depending on what has to be done about the car, based on rules.
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You’re welcome, as always–service with a smile!
BC
Nooooo, not more likely.
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yes they get flat wheels but its not the way most on here are stating, on most road engines the flat wheels are mostly caused by wet rail and no sand meaning that when you have the dynamic on and everything is going fine then the wheel slides because of the loss of traction the sand would have helped this from happening but if there is no sand the wheel will slide til the engine drops the load. it will load back up and most generally when it slides again it will be on the new flat spot making it bigger. You can hear these with no problem and if they are real bad they can be felt.
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flat spots are flat spots they are about the same but made differantly
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defect detector will not pick it up but if wheel is bad enough it will brake the rail.
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dispatcher is to be notified and also the shops ( closest to you or tone up moc)
Thanks for starting this thread, Ms. Mookie. Allow me add to it with the following questions that probably pertain to both locomotives and cars:
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Does a flat spot have to absolutely flat / straight across to be heard and a problem ? Or, is only a little flattening from the perfectly round configuration enough to be heard or felt ? I suppose the running speed has a lot to do with this.
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How long does a flat spot have to be before it is heard, as in a train passing by ?
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How long does a flat spot have to be before it is “condemnable” as being too long, and the wheel has to be “trued” ? Memory tells me that it’s 1-1/2", but I’m not enough of a mechanical guy to know that for certain. Is it the same for cars and locos ?
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What’s the current “state of the art” for truing wheels ? Does the axle have to be removed from the truck, or can that be done while still on the loco - with a “Lidgerwood” tool, or an under-track machine that the loco rests on, etc. ?
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Does a flat spot affect the loco’s pulling capability under heavy loads ? Is it more likely to initiate a slip when the flat spot is in contact with the rail, or doesn’t that matter much ?
Thanks in advance for any insight. Feel free to expand on these questions, too.
- PDN.
It was a wild detector that stopped the k 427 this past saturday near hamler.At first the crew thought it was their 2nd engine but it was their buffer car for an ethenol train.radio gets real active when a detector goes off.
stay safe
Joe
Paul’s # 9 was going to be my next question. Since engines are heavier and have traction motors, is repair something that can be done on a rip track in the yard or do they need to be done at the diesel shop?
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Both! What can start out as a defined flat spot will eventually have its corners rounded off. You won’t hear it any more, but it still pounds the rails and can will be picked up by a WILD. This is part of why WILDs have become increasingly popular.
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My 1988 AAR field manual says 2" or two or more adjoining that are 1-1/2". That’s for cars, but I think the same applies to locos.
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Locomotives typically have their wheels trued up on lathes that don’t required removal from the locomotive. The axle ends have centers machined in them to accomodate this. There is a plug in the end of a Hyatt bearing box you remove to get at it. For Timken, you take off the end cap. In the case of a condemnable defect found at a location w/o a wheel truing lathe, the wheelset has to be changed out. (usually the whole TM/wheel combo).
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I have never heard of or seen a study of this - or even heard any scuttlebutt or conjecture. My guess is it doesn’t matter much - at high TE demand, the wheel’s rotational velocity is so slow I can’t imagine the wheel would unload enough getting over the edge of the flat spot to cause a problem.
From NORAC 8th Edition. Ninth edition is in effect, but I don’t have that in digits right now
- Flat Spots
If a flat spot on a wheel of a car or engine develops en route, a member of the crew must inspect it. Upon completion of inspection, the train will be governed as follows:
a. Proceed at Normal Speed: The train may continue at Normal Speed if no other defects affecting movement are observed, AND if: - The flat spot is less than 2½ inches in length.
OR - If there are 2 adjoining spots, each is less than 2 inches in length.
b. Proceed at 10 MPH: If a flat spot is found in excess of either of the above dimensions, but less than 4 inches, and no other defect is observed, two actions must be taken: - Speed must not exceed 10 MPH.
- A report must be made promptly to the Dispatcher or Operator.
c. Remain Stopped: If a flat spot of 4 inches or greater is found, the train must remain stopped until a report is made to the Dispatcher or Operator. When determined safe for movement, the Dispatcher (or Operator when authorized by the Dispatcher) will order the car or engine to be set out at the first available siding or terminal.
Doesn’t really answer the “condemned” question, but might help provide some insight.
I know NJT and others now print a “ruler” in schedules and rule books to measure flat spots with specific instructions per length. A flat spot will not only pound the rail but also the wheel, truck, and car/lcomotitive in total. The wheel itself could eventually crack as could any other casted parts. A rider…read train crew…should be able to discern a flat wheel by both sound and feeling of the ride. And allowing it to go unattended could cause real problems; the sooner it is addressed, the safer everyone and everything is.
What I’m also wondering is:
- Just because you can hear a flat wheel from trackside - or feel and hear it from the inside of a passenger car while riding, as henry6 mentioned - how does that relate to what is not acceptable for further service ?
I’ve ridden some Amtrak Intercity and Regional trains in the 50 to 80 MPH speed range where there was a strong vibration and noise from one or both ends of the car - enough that I moved to the middle when possible to minimize its effect on me - but none of the crew seemed to care too much about it. Of course, it might not have been a flat spot - an out-of-round wheel, a wheel that was not at exactly 90 degrees to the axle and so wobbled a little bit, maybe a worn bearing, etc. - and maybe they had the apathetic attitude of “If the carmen/ Mechanical Dept. guys didn’t see any reason to take it out of service, I’m not going to be the guy who does”.
Nevertheless, it would be interesting to know if and what any “rule of thumb” or empirical correlation is between the “out-of-service” flat spot limit and felt or perceived noise and vibration. For example, if your drink vibrates across and falls off the tray or table, then the wheel is probably over the limit - or nevertheless, still nowhere near it, etc. Any insights on this ? Thanks.
- Paul North.
That’s a good idea! CNW used to have a ruler on its employee timetables, but it was for brake-piston travel. Wouldn’t have been a problem to put the flat-spot limits on that page, too. UP doesn’t do that, because the timetables are of a different format. The problem is, the only way that most crews have of detecting flat spots is to be riding on top of them. So freight crews usually don’t know about them unless a detector or bystander informs them.
Paul, that ruler does allow for a minor flat spot…less than a quarter of an inch I believe…to allow for normal speed running. It will make noise and vibrations, but is not dangerous. Supposedly. Because if it is ignored completely it could become worse or cause other problems. It does, or should be, reported by the crew at the end of each run. I ridden many a NJT trains with flat wheels, at speed, with only the noise and the vibration being annoying to me but not the crew!
My best guess is worn wheels - perhaps with a “false flange” - the initiated truck hunting. That the problem was at higher speeds it the tip off.
We have a certain remote job that attaches their robot engine to the inbound road power and uses that to switch with. Always gives the road engines flat spots. (full throttle or full independent is how they operate). We now have special detectors (solid state impact detectors - SSID) that detect and will sound an alarm if a car or engine has excessive flat spots. THe SSID around here is located before you get on Amtrak, so a bad car won’t wreck amtrak’s rail.