tleary01 I have been following this thread and have some comments and information to add.
For sure you did have a lot to add! Thanks for the information you gained through years of experience.
I have been following this thread and have some comments and information to add.
In more than 45 years in the railroad industry I have never knew of a road or switch crew reporting flat spots. It is always Old Flats ie: not of my making.
Dynamic Brake itself cannot flat spot a wheel. The wheel and traction motor armature must have movement to produce dynamic brake retarding force. If the locomotive wheel comes to a complete stop dynamic brake force will be zero. Dynamic brake alone can cause a wheel to “skid” on the rail, and if the wheel slip control cannot quickly correct the “skid” surface metal on the wheel will be “displaced” from the intense heat generated causing “built-up tread” . The displaced metal is brittle and will shatter out leaving a shelled tread. Flats generated during dynamic brake are the result of applying the locomotive air brake. The combination of dynamic brake retarding force and even a light air brake application can stop wheel rotation , then the wheel slip control will reduce the dynamic brake but the flat spot is made. Virtually all locomotives with dynamic brake (BNSF is the exception) employ the Dynamic Brake Interlock (DBI) function of air brake that prevents automatic brake application on the locomotive when operating in dynamic brake. DBI acts as a back-up that prevents automatic brake cylinder pressure even though operating rules require that automatic brake applications “bailed-off” on the locomotive. The locomotive independent brake, however, can be applied any time, and when reviewing an event recorder download for evidence of the cause of wheel flats, applications of independent brake during dynamic brake are the evidence.
Flats or wheel shelling can affect the tractive effort of a locomotive. All locomotives since the EMD 50 series and GE Dash 8 series employ a traction control system that drives the wheels into a “creep” condition during high tractive effort in order to gain increased adhesion. Damaged wheel tread surface reduces the effectiveness of this wheel creep traction control.
The “state of art” in locomotive wheel trueing is not the portable wheel turning lathe device referenced by Paul North. For more than 25 years the “Standard“ has been the Simmons-Stanray Under Floor Wheel Trueing machines installed in locomotive shops of all class 1 railroads. A description of the machine can be found at: http://www.simmons-albany.com/group/index.php?option=com_content&view=article&id=51&Itemid=96
The locomotive is moved over the machine and the wheel set is held by its axle centers while the cutting head mills the wheel tread. This machine is not a lathe, though under floor wheel lathes are also available though not so commonly used in locomotive shops. The milling head can be made to any profile specified by the user. Most railroads today true locomotive wheels to either the “UNIPOINT” or the AAR -1B profiles.
The article on Implementing Anti Wheel Shelling Profiles, http://www.interfacejournal.com/features/08-05/wheel_shelling/1.html
shows a comparison of the tread profiles of the Heumann and AAR 1B treads, the Unipoint profile is similar. Unlike the AAR 1:40 or 1:20 that are uniform tapers from the root of the flange to the edge of the wheel, each of these profiles are parabolic shaped as the profile approaches the flange. This causes the wheel to make a single point of contact with the rail that both bears weight and steers the wheel. These are called “worn wheel profiles” because a perfectly worn wheel will take on this shape if it stays in service long enough. By starting with a tread profile that is close to the worn wheel shape flange wear is virtually eliminated. Where a 1:20 tapered wheel will require trueing for a thin flange at about 50-60 thousand miles of normal service, Unipoint and similar profiles will require wheel true at about 150 thousand miles for “high flange” which is actually tread worn so the center of the tread to the top of the flange greater than 1.5 inches.
Locomotive emergency brake application under good rail conditions, rail sanding, and proper cylinder pressure does not cause wheel sliding. Rules typically instruct the operator to “bail off “ the locomotive brake during emergency stops to permit the weight of the locomotives to keep some stretch on the train during a stop. Unless the train has broken near the locomotive, bailing off the locomotive brake has a no measureable effect on stop distance. The way that locomotives get flats during an emergency stop is to not bail off and then apply the independent brake on top of the emergency application, this “stacking”can produce nearly 100 psi brake cylinder pressure on locomotives with composition brake shoes, where emergency only pressure is normally 75 psi and independent pressure is normally 72 psi. Some railroads add a feature that prevents brake cylinder pressure “stacking” but most rely on the engineer to follow rules.
Not having done a "scientific" study on the subject, I can only relate that it seems to me that most of the cars I have encountered with significant flat spots (reaching out to that 5 car length threshold) are tank cars.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Consider this Paul,
If all you felt was a slight tingling in your feet from the flat spots...then perchance the track structure was doing its job correctly.
Folks tend to think the track structure is rigid, when in fact, it is designed to sustain a lot of impact and flex to absorb that pounding.
And dont be fooled by spalling in disguie as flat spots...spalling often makes a rumbling sound followed by a banging as the wheel drops back one to the rail off the spall.
23 17 46 11
jeffhergert [snip] My own, unscientific, unsactioned rule of thumb is if you can hear the flat spot (on cars during a roll-by) about 5 or 6 cars before or after, it should be looked at. Most flat spots seem to fade away after 2 or 3 cars. [snip] I devised my own rule of thumb when I was inspecting for a reported flat spot. The engineer was pulling the train past me and I wondered how I was going to tell the difference between the many flat spots. When I heard it, there was no question that there was a problem. Since then I've used the 5 or 6 car rule, but don't claim it's 100% reliable. Jeff
[snip]
I devised my own rule of thumb when I was inspecting for a reported flat spot. The engineer was pulling the train past me and I wondered how I was going to tell the difference between the many flat spots. When I heard it, there was no question that there was a problem. Since then I've used the 5 or 6 car rule, but don't claim it's 100% reliable.
Jeff
I had a chance to try this out at lunchtime today. Two NS EB trains came through Emmaus - a really long unit coal train at about 12:35 EST at about 35 MPH, and 10 minutes later about 55 RoadRailers at about 40 MPH. I was standing on a sidewalk just behind the crossing gates. At most, I was hearing a flat wheel about 2 car-lengths away - no more. Some seemed a little noisier than others, but all within the range of what I would call "normal" - nothing to cause me to move back.
Interestingly - I was wearing hard-soled street shoes - when the flat wheel was closest to me I could feel the vibrations from 2 or 3 impacts through the soles - again nothing extreme, but definitely a tingling happening with them that wasn't happening with the others. Maybe if I can get a calibration on my shoes and feet I can then go rent my services as a self-propelled WILD to rrboomer's CP operation . . .
Have a good weekend, everyone !
- Paul North.
zardoz Paul_D_North_Jr More common are cars and pedestrians, which are of no or minimal direct danger to the locomotive and its crew. If there's time to blow the horn, there's usually time to recognize the situation as such, and then to work the brakes in accordance with the rules and procedures. Particularly, if it is as I anticipate, it won't make much difference in the end. The only reason to plug it before hitting a car or pedestrian is to shorten the walk back to the scene. However, there are a few really good reasons to NOT go directly into emergency, mostly unwanted and uncontrolled slack action.
Paul_D_North_Jr More common are cars and pedestrians, which are of no or minimal direct danger to the locomotive and its crew. If there's time to blow the horn, there's usually time to recognize the situation as such, and then to work the brakes in accordance with the rules and procedures. Particularly, if it is as I anticipate, it won't make much difference in the end.
More common are cars and pedestrians, which are of no or minimal direct danger to the locomotive and its crew. If there's time to blow the horn, there's usually time to recognize the situation as such, and then to work the brakes in accordance with the rules and procedures. Particularly, if it is as I anticipate, it won't make much difference in the end.
However, there are a few really good reasons to NOT go directly into emergency, mostly unwanted and uncontrolled slack action.
Now days.. when the plaintiff lawyers get ahold of the engines download it better show that your train was in emergency .They don't want to hear about slack action and whatnot.
Paul_D_North_Jr What I wonder in such situations is how much of a practical difference it actually makes in stopping the train from either keeping on or "bailing off" the locomotive brakes, and/ or using the independent brakes instead. Can any of the working railroaders comment on that ? For a heavy 100-car coal unit train, obviously it might not make much of a difference, whereas for a light 3-car passenger train it might make a big difference.
What I wonder in such situations is how much of a practical difference it actually makes in stopping the train from either keeping on or "bailing off" the locomotive brakes, and/ or using the independent brakes instead. Can any of the working railroaders comment on that ?
For a heavy 100-car coal unit train, obviously it might not make much of a difference, whereas for a light 3-car passenger train it might make a big difference.
The Metra locomotives have what they call a "blended brake". When the air is set, the air brakes on the locomotive set, while at the same time the dynamics are setting up. When the dynamic actually kicks in, the locomotive air brakes are automatically bailed off proportionately to the amount of dynamic. If you set the jammer on top of the dynamics, the dynamics automatically drop out.
After all I have said, I do believe that a trained and seasoned engineer knows how to size up each situation and that each situation is different from the other. Therefore he/she is capable of making the correct and safest decision in any given circumstance.
RIDEWITHMEHENRY is the name for our almost monthly day of riding trains and transit in either the NYCity or Philadelphia areas including all commuter lines, Amtrak, subways, light rail and trolleys, bus and ferries when warranted. No fees, just let us know you want to join the ride and pay your fares. Ask to be on our email list or find us on FB as RIDEWITHMEHENRY (all caps) to get descriptions of each outing.
I don't think Wabash was referring entirely to an emergency application initiated by the engineer. What I look for are the engineers that don't bail during an undesired emergency . In my experience most locomotive flat spots are isolated to only a couple wheels.. the ones the handbrakes use...
I believe legally, yes, the engineer is required to stop when an object is struck. If it is not an emergency, he may stop with normal application of brakes and need not go into emergency.
And I agree, Paul, if there's time to blow the horn, there's time to react with normal procedures. I was just pointing out that there are times when reaction is reflexive with little time for procedures.
Paul_D_North_Jr If there's time to blow the horn, there's usually time to recognize the situation as such, and then to work the brakes in accordance with the rules and procedures.
If there's time to blow the horn, there's usually time to recognize the situation as such, and then to work the brakes in accordance with the rules and procedures.
Is an engineer required to put the train in "emergency" if he has hit something or somebody? For example if a train comes around a corner and clips the back bumper of a tractor trailer. Can the engineer bring the train to stop with a "full service application"? Is it a judgement call?
Former Trains Editor David P. Morgan once said something to the effect of, "A gasoline tanker truck on a crossing is the ultimate incentive for the engineer to 'big-hole' it" (or similar). As you say, in such a circumstance the resulting slid flat spots on the loco wheels are going to be the least of anyone's concerns if there's any kind of impact - and if not, then everyone will be relieved enough to still be alive that the subsequent criticism (if any) will seem trivial by comparison. But fortunately, such situations are rare.
- PDN.
Reactive procedures are fine and defined. But we are also talking time and reflexive actions. I don't care what the rule book says, an engineer sees danger in front of him, he dumps the air and dives behind something to shield himself. Its reflexive action that happens in split seconds. And while there are rules and regulations and procedures there are also specific circumstances.
wabash1 henry6 In trouble only if one caused flat spot by inappropriate operation or control of the locomotive or train. An emergency application in the name of safety would not be punishable but over applying brakes, or braking too harshly because of excessive speed, or innatention to duties, then, yes, one would be in trouble. How can you say this with a straight face? If i was your boss and you brought me a engine with flat spots after a emergency application id fire you on the spot. there is no reason to have flat spots on engine from braking. including emergency applications that is why you bail the brakes. simple and effective. [emphasis added - PDN.]
henry6 In trouble only if one caused flat spot by inappropriate operation or control of the locomotive or train. An emergency application in the name of safety would not be punishable but over applying brakes, or braking too harshly because of excessive speed, or innatention to duties, then, yes, one would be in trouble.
In trouble only if one caused flat spot by inappropriate operation or control of the locomotive or train. An emergency application in the name of safety would not be punishable but over applying brakes, or braking too harshly because of excessive speed, or innatention to duties, then, yes, one would be in trouble.
How can you say this with a straight face? If i was your boss and you brought me a engine with flat spots after a emergency application id fire you on the spot. there is no reason to have flat spots on engine from braking. including emergency applications that is why you bail the brakes. simple and effective. [emphasis added - PDN.]
I think what we have here is "a failure to communicate" - either that, or a little education or clarification is needed, as follows:
"Bail the brakes" in this context means releasing the brakes - that are controlled by the train's air brake system - on the locomotive wheels (only). The rest of the train's brakes remain applied in emergency. To restore the locomotives' braking effect, there is also the independent locomotive brake available for use. For more details, see Al Krug's explanations of "Locomotive Brakes" and "Independent Brakes" near the bottom of his web page on "Freight Train Air Brakes of North America" at the link for "How RR air brakes work - I" of his "Railroad Facts and Figures" website - http://www.alkrug.vcn.com/rrfacts/rrfacts.htm - at:
http://www.alkrug.vcn.com/rrfacts/brakes.htm#locomotivebrakes
For a heavy 100-car coal unit train, obviously it might not make much of a difference, whereas for a light 3-car passenger train it might make a big difference. This too is in the context of usually hitting and going on past whatever it was on the track that motivated the emergency application in the first instance, and then stopping someplace much further down the track. Stated another way, the obstruction is probably going to get hit anyway, so what difference does a couple of tenths of a second - or even a few seconds - in how soon the train gets to the obstruction going to make in the outcome ? Is the obstruction really likely to move off the track in that very short change in the time interval, given that it was there already, and since it hadn't already used the opportunity to have done so while the train was approaching and braking ?
Looking forward to the responses !
You mean that if a child is on the track in front of you or a road vehicle fouls a grade crossing or your train spilts in two, times when there is an emergency application of brakes, the engineer will get blamed for not trying to kill a kid, hit a vehicle or for not keeping his train together...(or does the conductor get charged with that?)?
See? This is an educational forum! I just learned something that I'll remember when I start officially learning to run a locomotive (hopefully this year). (I kinda knew that already with regard to regular braking, but might not have thought about it while I was hoping we didn't hit whatever I was dumping the air for.)
How can you say this with a straight face? If i was your boss and you brought me a engine with flat spots after a emergency application id fire you on the spot. there is no reason to have flat spots on engine from braking. including emergency applications that is why you bail the brakes. simple and effective.
Here are a couple of items on the subject of wheel repair:
http://www.encyclopedia.com/doc/1G1-20996429.htmlhttp://www.railwaywheelsrepair.com/
A Google search on "portable railroad wheel lathe" turned up (pun intended) several more.
Given the obviously easier option of simply replacing the wheelset, my idea really doesn't have much value for most applications. I was responding to the assertion that the device wouldn't work on a car because cars don't have traction motors. Details notwithstanding, I simply presented a way that someone could turn the wheelset.
That said -
Splitting the chain would be no problem - bicycle-type chains always have a link specifically for that purpose.
No question that you'd have to raise both sides of the wheelset off the rail. I'm no expert on their construction, and don't have one in front of me right now, but would surmise that it wouldn't be all that difficult to do.
I'm sure a frame could be designed that would offer the necessary support and adjustment for the drive motor, whatever form it took (air, hydraulic, gas, electric).
Whether it was used on the truck or as a fixed facility in a shop (onto which the offending wheelset could be mounted), the combination of the milling device and a drive mechanism such as I suggest might provide a small railroad the ability to deal with relatively minor wheel work in-shop as opposed to shopping it out (at least for the equipment they own).
I'd hazard a guess that the drive device could be built for under $5,000, keeping the overall price under $10K. The axle sprocket would be the most expensive part as that would need to be specially built and machined. Virtually everything else could be purchased off-the-shelf or fabricated in-house.
Even in the field, they replace the wheelset. Jack up the truck, roll out the bad, roll in the good, lower the truck onto the new wheelset, take the bad wheelset back to the shop.
I have to ask, where are you going to mount this chain/drive gear to turn the wheel in-place in the truck? How is the other end going to turn if it is resting on the rail? At best, you would need a split gear that bolts together (as you suggested) around the outside of the axle and your chain would have to be split also to get it over the wheel to the drive gear, after the truck frame was lifted out of the way. By the time you do that, you might as well lift it so you can remove the whole wheelset.
Hmmm - sounds like a good idea. I wonder, though, if it's generally just easier to move the car to a RIP track where it can be jacked up and the entire axle replaced. Then, the axle & wheels can be forwarded to a shop that's equipped with large-scale and sophisticated machines to do that truing work much faster and to closer tolerances.
That said, though, here's a couple of thoughts:
- I'm not sure that the axle diameters vary all that much. I believe they usually have a taper, and that may be a way to find a location on each that has a common diameter with other axles. Alternatively, use some kind of bushing to make the smaller axles a little larger to better fit the drive mechanism (belt or chain).
- Consider using either an air or hydraulic motor to drive/ turn the axle and wheel assembly. They should be a lot lighter to lift and carry to place near the axle than either electric motors or gas engines, and their power source - say, a gas-powered hydraulic pump or air compressor, etc. - can stay on or behind the service truck and not have to be hauled over and lifted up either, etc.
Let's see what else comes up here. Larry, you now know where the company is if you want to talk to them - they seem to like the innovative projects.
Finally - I meant to say this before: It's great to see a company that actually innovates and makes things that is still in the U.S.A. - in the "UP" of Michigan, even ! - and appears to be committed to quality and staying up to date with technology. (Look over their website and you'll see why I say this.) So I hope they are weathering the recession well, and keep up the good work !
That's an interesting concept - a modern version of the "red slippers" that were apparently used on steamers to do about the same thing, only while the locomotive was actually moving. (As related in a Trains "Railroad Reading" article about "Rule 13 Sand.")
About how many RPM does the wheel turn when configured as described?
It occurs to me that it might be possible to build a device to turn a freight car wheel. A two-piece sprocket or pulley could be clamped onto the axle, with an electric or gas engine used to drive the chain or belt. Securing the whole assembly a la traction motor would be one challenge, and differences in axle diameters would be another. Assuming one could get enough HP and speed out of such an arrangement, it might just work.
Using the gas engine would allow such work to be done virtually anywhere - even on a siding in the middle of nowhere.
OK ! Thanks, Randy. Interesting website and company - it is the "Independent Machine Company of Gladstone, Inc." - I see they also make gear cases and snowplows for locos, as well as other specialty items.
The page for their own "Iron Horse Portable Wheel Lathe" is:
http://www.imc-info.com/ironhorselathes.html
Unfortunately, it doesn't have a lot of detail about how it works. But that's more than I had before, and a starting place to learn more.
Thanks again.
These are manufactured by independant machine tool in either Gladstone or Escanaba Mi. The last price I had on this portable wheel lathe was around $4000.00.
Though I've never used one I have read the instructions before I bought one, the lathe is attached to the locomoive truck , probably where the pedastal jaw liners attach. The wheel is jacked off the rail using the case of the traction motor, there are jacking lugs on the bottoms of the motors. The motor leads are disconnected and reconnected to a welder, The "A" lead and the "FF" lead are connected tot he power supply and the "AA" lead and the "F"lead are connected together , making a series loop. The wheel is turned by the welder and the cutter pressed against the wheel. Sadly this machine has no way to cut wheels other than locomotives, you need a traction motor to make the thing work. The time to profile a wheel is lenghty as well but it is worth the savings. The operator of the device must be very skilled as well , there is no sylus to guide the cutter , you must visually verify an accurate profile.
http://www.imc-info.com/
Randy, thanks for bringing this back up !
Because, I forgot to ask WSOR 3801 (or you) to explain how this wheel-truing device works when in action. I know the red cylindrical device in back of it (looks kind of like a large soup can) is a hydraulic jack - is that the one you use to jack up the wheel to be trued ? What do you use for a lifting point on the wheel / axle/ traction motor - the outside bearing box/ case ? Since it's near or over the pit, what do you use to support the bottom of the jack ? How high above the rail do you need to jack it ?
With regard to the wheel-truing device itself, how is it attached to or fitted to the wheel to be trued ? It looks too tall to just slip under the wheel above the rail, and too short to rest on the pit floor and still reach all the way up to the wheel. Where are the cutting heads or edges ? What is the large handwheel to the left used for ? Is that a turntable or "lazy susan" kind of thing in the middle of its height ? I also see a large coimbination wrench laying on top of it, and a large socket wrench on the floor in the background. Are they used to set, tighten, or adjust this device - I see a number of bolts and perhaps adjustments, such as what appears to be a shaft on the near side down low on the sunlight "tail" that looks like the drive for a scissors jack ?
Any information and insight that you can provide will be appreciated. Feel free to send me (us) to a manufacturer's website, if that would be more convenient. Thanks !
WSOR 3801 The latest wheel-truing device. The rest of the setup. Green bin to put the shavings in, the device, and the welder. The welder is hooked up to the traction motor of the wheel being trued. The wheel is jacked up, the welder gets turned on, and a guy stands in the pit working the device. Always helps to hook the traction motor back up properly when done. CP has a WILD detector somewhere between Portage and La Crosse. There are sidings nearby chock full of cars flagged by the detector. One time the patrol had the engines flagged, but were told to keep going.
The latest wheel-truing device.
The rest of the setup. Green bin to put the shavings in, the device, and the welder. The welder is hooked up to the traction motor of the wheel being trued. The wheel is jacked up, the welder gets turned on, and a guy stands in the pit working the device. Always helps to hook the traction motor back up properly when done.
CP has a WILD detector somewhere between Portage and La Crosse. There are sidings nearby chock full of cars flagged by the detector. One time the patrol had the engines flagged, but were told to keep going.
Must be Janesville .. Your former shop manager left his Irish mark on the scrap bin !
rrboomer - OK ! Thanks - the voice of real-life experience - the insight is much appreciated.
I was mindful of the 3" dimension on the flat spots that are not detected as you noted, and wondered if that was a factor in which ones are and are not detected ?
Also, does speed have anything to do with which ones are detected, in your experience ?
You're right that it is counter-intuitive. I'd otherwise think that equipment sensitive enough to pick up an out-of-round wheel - after all, how bad could that be, right ? - would surely be able to pick up a flat spot, but evidently not.
Did you have a chance to review the TSB's report on the CP's derailment that I also linked ? I'm wondering how the changes recommended and implemented since then (July 2004) are working out in real life, since it seems that would pretty much correspond with your experience ?
One thing that now puzzles me as an institutional thing about these changes for UTOs per that report and TOLs as zugmann mentioned above, though, and this is as good a place as any to point it out:
If the WILDs are not picking up all the wheel defects, then the railroads seem to be relying on (or at least treating) these Unidentified Track Occupancy and Track Occupancy Light procedures as an indication of a possible rail break from the wheel defect, and on that basis inspecting the track and then the train if that is what has occurred. In other words, it's the broken rails that now seem to be functioning as the wheel defect detectors, not the WILD equipment ! Maybe I'm exaggerating this too much - but after reading through that TSB report (what was it - something like 9 broken rails that night ?) and the new CP procedures, that's the conclusion I come to from the instructions that if UTOs start to occur after a train has passed, then inspect the train. Because if the wheel is really bad, then the only valid multiple UTOs in those circumstances will actually be from broken rails, right ? I'm sure my colleagues in the track departments will be none too thrilled at this revelation.
Anybody have any other or differenet viewpoints on this ?
Thanks again for the comments, rrboomer.
rrboomer Paul, I know, it sounds counter-intuitive that a wheel load impact detector doesn't find flat spot impacts. What I said was based on several years worth of stops with the CP's WILD detector between Hastings and Red Wing. Paul_D_North_Jr rrboomer - Can you elaborate / provide more details ? At least 1 manufacturer seems to claim that the WILD will detect flat spots, as well as the out-of-round wheels that you mention. See: http://www.salientsystems.com/prod_wild.html , which says (in part): "Wheel defects with spalling, shelling, slid flat, or out-of-round characteristics impart excessive impact loads. Caught early, they can be trued. Undetected, these wheels can damage thousands of miles of track or cause derailments. Proactive railroads use networks of WILDs to control broken wheels, burnt-off journals, hot boxes, and brake rigging damage by removing high impact wheels, reducing derailments as a result." [emphasis added - PDN.] Thanks for any insight you can provide ! - Paul North. rrboomer A "Wild" detector will seldom catch a flat spot. It is used to catch out of round wheels, but not 3" flat spot cars. Yes, a locomotive can get out of round wheels.
I know, it sounds counter-intuitive that a wheel load impact detector doesn't find flat spot impacts.
What I said was based on several years worth of stops with the CP's WILD detector between Hastings and Red Wing.
Paul_D_North_Jr rrboomer - Can you elaborate / provide more details ? At least 1 manufacturer seems to claim that the WILD will detect flat spots, as well as the out-of-round wheels that you mention. See: http://www.salientsystems.com/prod_wild.html , which says (in part): "Wheel defects with spalling, shelling, slid flat, or out-of-round characteristics impart excessive impact loads. Caught early, they can be trued. Undetected, these wheels can damage thousands of miles of track or cause derailments. Proactive railroads use networks of WILDs to control broken wheels, burnt-off journals, hot boxes, and brake rigging damage by removing high impact wheels, reducing derailments as a result." [emphasis added - PDN.] Thanks for any insight you can provide ! - Paul North. rrboomer A "Wild" detector will seldom catch a flat spot. It is used to catch out of round wheels, but not 3" flat spot cars. Yes, a locomotive can get out of round wheels.
At least 1 manufacturer seems to claim that the WILD will detect flat spots, as well as the out-of-round wheels that you mention. See:
http://www.salientsystems.com/prod_wild.html , which says (in part):
"Wheel defects with spalling, shelling, slid flat, or out-of-round characteristics impart excessive impact loads. Caught early, they can be trued. Undetected, these wheels can damage thousands of miles of track or cause derailments. Proactive railroads use networks of WILDs to control broken wheels, burnt-off journals, hot boxes, and brake rigging damage by removing high impact wheels, reducing derailments as a result." [emphasis added - PDN.]
Thanks for any insight you can provide !
rrboomer A "Wild" detector will seldom catch a flat spot. It is used to catch out of round wheels, but not 3" flat spot cars. Yes, a locomotive can get out of round wheels.
Yes, a locomotive can get out of round wheels.
Thanks, Jeff ! Good photos - and I could spend a lot of time in that Interface Journal on these kinds of things . . . .
Our community is FREE to join. To participate you must either login or register for an account.