East Palestine wreck

[Euclid]

7j43k

Did plain bearings fail catastrophically?

 

 

Ed

Yes definitely.  They got overheated for various reasons, set the oil on fire, burned up the oil, then got hotter with the rising friction, then melted the babbit liner on the bronze; and then melted the axle, the bronze, the wedge, the bearing box, and the end of the portion of the axle that engages the bearing.  

It was similar to the failure of roller bearing, but it happened more frequently with plain bearings.  

[7j43k]

Did plain bearings fail catastrophically?

 

 

Ed

[Overmod]

Shadow the Cat's Owner will chime in here, with distinctive competence, but I suspect that the additional qualified drivers for even a tiny percentage of the hazmat that currently moves routinely by rail won't be available, or will involve such costs as to make the truck alternative higher than anything a sensible rail mandate might involve.

[diningcar]

If railroads are required to handle these shipments in some restricted way they will certainly have to raise the rates charged. This may then result in trucks hauling the commodities. Do we want them on the highways, and through our communities and cities?

[Euclid]

charlie hebdo

 

 

PennsyBoomer

Regardless, I think one upshot of this event will be that shipments such as vinyl chloride do not belong in high tonnage 150 car trains anymore.

 

 

Beware!  Those defenders will attack you as a kneejerker.

 

Much of the railroad labor advocacy agrees with the suggestion by PennsyBoomer.  It would be interesting what the forum consensus is, and whether it agrees or disagrees with the premise of PB's upshot speculation. 

[tree68]

PennsyBoomer

Regardless, I think one upshot of this event will be that shipments such as vinyl chloride do not belong in high tonnage 150 car trains anymore.

What are the options?  

You don't want to put all the hazmat in one train (see: Dow Death Train).

In this case, a shorter train might have meant less cars piled up behind the derailed car, but if those cars that did still pile up included hazmat, the result would have been the same.

We can lessen the probability of a repeat of this incident, but, as been aptly noted by many, completely preventing a recurrence is virtually impossible.

 

[Overmod]

I have seen a number of discussions (but have no citations) that restricting all PIH and hazmat to specific key trains only (and this potentially goes with re-imposing key train speed limits) is an invitation to activism or outright terrorism in the current climate (where people feel empowered to tamper with signal systems or mess with switch positions in the hope of provoking discrediting consequences).  The flip side of key train concentration is that if an event occurs to one, the consequences can be more severe, especially if the various derailed or damaged loads can synergistically react.

In the East Palestine case, much of the controversy involves a 'block' of vinyl chloride tanks, one of which started to suffer runaway polymerization that would cause it to detonate.  Since (in the opinion of those who were there) this one car could not be relieved without "relieving" the other four around it, we got a massive release of monomer, which was then strategically ignited 'of necessity' but not for some time after the release clouds began to expand.  Perhaps this suggests that spacing explosion or BLEVE hazards several 'more inert' cars apart in a consist, and reassembling them in a block only for last-mile delivery, would be a workable alternative.  (Unfortunately in this era of flat-switched blocks for cheapness, I don't see this being adoptable...)

[charlie hebdo]

PennsyBoomer

Regardless, I think one upshot of this event will be that shipments such as vinyl chloride do not belong in high tonnage 150 car trains anymore.

Beware!  Those defenders will attack you as a kneejerker.

[PennsyBoomer]

Small consolation for East Palestine, yet had this derailment occurred another twenty miles to the east, it would have directly impacted the Beaver and Ohio rivers and greater population centers. Indeed, NS had a rather dramatic 24 car ethanol spill on the Beaver River bridge in 2006.

https://www.epaosc.org/site/site_profile.aspx?site_id=2611

While most of the dialogue seems to be about detectors, and they are certainly an important consideration, it is doubtful enough devices can be installed to prevent the anomaly. I would suggest that it may be advisable to examine isolating certain highly toxic loads in controlled consists.

Over the years the movement of high and wide shipments has presented problems with regard to clearance on adjacent tracks with overhanging loads, swing-out loads on curves or vertical clearance restrictions. In endeavors to minize delays to traffic, some roads have run high and wide specials to corral these shipments onto smaller trains that can clear opposing or passing trains on short spread track segments or sidings. PRR, PC and CR did this, as well as UP and I would imagine other roads to some extent.

While transit time would be affected and shipment costs would increase, the thought is that corraling these highly toxic loads onto more or less exclusive consists of restricted length, perhaps more restrictive speeds and more restrictive inspection processes enroute might have a mitigating affect upon potential disasters. Regardless, I think one upshot of this event will be that shipments such as vinyl chloride do not belong in high tonnage 150 car trains anymore.

[Overmod]

7j43k

PS:  Thought it wouldn't hurt to research my own "question", and I found this from 1992: https://railroads.dot.gov/sites/fra.dot.gov/files/fra_net/15067/Roller_Bearing_Failure.pdf

 Highly interesting in the context of this accident.

Note the condition of the damage to "Bearing B" and then read the description of overtemperature observation during 70mph testing.  On p.45 you will note that the typical wayside indicator tends to read temperature from the outside bearing race and 'below' whereas the highest developing temperatures concern the inner race at the top (where the cups sit in the bearing adapter).  Then look at the result noted on p.50 where the temperature of the damaged test bearing B increased 256F in 20 minutes at 60mph.

[SD60MAC9500]

 

Bearings go bad unfortunately this bearing burnt off in place that just happened to be East Palestine.. As well I know people are giving NS the 10th degree on bearing/wheelset inspection. However the covered hopper that initiated the derailment came off of UP. Did UP bother to do a proper inspection? More than likely this bearing was already in a poor conditon on the UP.. All this will come up in the cars MD-11 history. 32N originates in Madison, IL off the TRRA and carries quite a bit of UP interchange traffic from the Texas/Gulf to the East Coast..

 

 

[7j43k]

oltmannd

Bearings that fail apparently don't all progress at the same rate.  Some will operate many miles while failing.  Some will be okay and then fail to burnoff in a few miles.

 

 

Then if you want to protect against train wrecks due to wheel bearing failure, you can either:

install reliable detectors closer together than "a few miles",

or

install reliable detectors on all bearings on all cars,

or

install wheel bearings that will not fail in "a few miles",

 or

 accept that there will be "some" train crashes due to bearing failure.

 

 I added the "no-fail" bearings because it would seem far past time to not to have researched WHY a bearing would fail quickly, and what to do about it, if anything.  If the bearing had not (quickly) failed in East Palestine, there likely would have been no wreck.

Since that's the direct cause of the wreck, it would seem that the NTSB would research the matter.

 

Ed

 

PS:  Thought it wouldn't hurt to research my own "question", and I found this from 1992:

https://railroads.dot.gov/sites/fra.dot.gov/files/fra_net/15067/Roller_Bearing_Failure.pdf

Don't have time to read it right now, though.

[oltmannd]

Euclid

I assume the bearing produces heat when running normally, depending on its load.  So a bearing running with a constant load within a constant ambient temperature would always be the same bearing temperature; which would be the constant bearing operating temperature plus the ambient temperature.  And that constant temperature of the bearing would be above the ambient temperature.

 

So, under that running condition, if the bearing temperature started to rise, that would be abnormal or an anomaly.  It seems to me that would have mean that something is wrong with the bearing.  

 

So, I would think that hotbox detectors should be looking for any temperature that exceeds operating temperature plus ambient temperature.  But then if braking is adding heat to the detection zone, that can throw the meaning of the hotbox detector temperature readings.  So you would want to allow some heat rise in the bearings before taking any action to stop and inspect. 

 

Also the ambient temperature will not be constant.  It will probably be changing most of the time.  So the sensors would have to constantly revise what is considered normal.  Also, even ambient temperature alone only includes air temperature.  Yet the heating of objects will also depend on solar gain which does not directly affect air temperature.

 

I would guess the term “detector temperature reading above ambient” is just a way of saying “temperature reading above background.”  And that would include ambient temperature plus heat produced by the bearing.  Overall, it seems like it would be difficult to see a trend that predicts a bearing failure with certainty. 

 

That points to a need to have more frequent detectors.  For instance, if you had one every 100 feet, there probably would never be a bearing failure.  They could let the temperature rise until a failure was certain, and still have time to stop the train. 

 

 

HBDs compare side with side and other axles on same car.

UP came up with method to trend from detector to detector (combines AEI data and digital detector data) 5 or 10 years ago. Don't know how/if NS implemented. 

Acoustic detectors looked promising as bearings get noisy before they get hot. NS had a few...Don't know status.

[oltmannd]

Bearings that fail apparently don't all progress at the same rate.  Some will operate many miles while failing.  Some will be okay and then fail to burnoff in a few miles.

 

Wayside detectors would be hard pressed to catch them all.  Nearly all? Yes. All? No.

[mudchicken]

Euclid

But rather that placing detectors 100 feet apart along the track, you could place them on the train and get the same benefit of real time monitoring.  

They would have to work reliably first and be proven to work - has not happened yet. TTC/MxV has seen plenty of fails.

[Euclid]

I expect the next shoe to drop will be the discovery that this spill is far more dangerous than was previously thought.  Investigations will zero in on exactly who approved the burn-off.  There will be claims that the airborne cloud had spread deadly carcinogens all over large portions of the country. Buying and removing the entire town of East Palestine will become part of the remediation.  The cost will be far greater than what NS can cover, but also, they may be simply relieved of the obligation beyond what they are able to pay. 

 

We will be left with a secured area that will be contained, but never returned back to its condition prior to the derailment.  Dilution will be the main process of the “cleanup”.  With the chemicals in the watershed all the way to the Gulf of Mexico, there will be a lot of dilution.   

[Euclid]

But rather that placing detectors 100 feet apart along the track, you could place them on the train and get the same benefit of real time monitoring.  

 

[charlie hebdo]

Perhaps NS could use this oldie by Talking Heads for commercials? Just change the lyric to "Burning Down the Town" to be more relevant?

https://youtu.be/_3eC35LoF4U

 

[BaltACD]

The Hot Box Detector engineers are way way ahead of you Euc.

[Euclid]

I assume the bearing produces heat when running normally, depending on its load.  So a bearing running with a constant load within a constant ambient temperature would always be the same bearing temperature; which would be the constant bearing operating temperature plus the ambient temperature.  And that constant temperature of the bearing would be above the ambient temperature.

 

So, under that running condition, if the bearing temperature started to rise, that would be abnormal or an anomaly.  It seems to me that would have mean that something is wrong with the bearing.  

 

So, I would think that hotbox detectors should be looking for any temperature that exceeds operating temperature plus ambient temperature.  But then if braking is adding heat to the detection zone, that can throw the meaning of the hotbox detector temperature readings.  So you would want to allow some heat rise in the bearings before taking any action to stop and inspect. 

 

Also the ambient temperature will not be constant.  It will probably be changing most of the time.  So the sensors would have to constantly revise what is considered normal.  Also, even ambient temperature alone only includes air temperature.  Yet the heating of objects will also depend on solar gain which does not directly affect air temperature.

 

I would guess the term “detector temperature reading above ambient” is just a way of saying “temperature reading above background.”  And that would include ambient temperature plus heat produced by the bearing.  Overall, it seems like it would be difficult to see a trend that predicts a bearing failure with certainty. 

 

That points to a need to have more frequent detectors.  For instance, if you had one every 100 feet, there probably would never be a bearing failure.  They could let the temperature rise until a failure was certain, and still have time to stop the train. 

[CSX Robert]

Murphy Siding

Why is the measurement compared to ambient temperature and not the actual tempurature? Our area has temps between -30 a and +115. Why would ambient temperature matter? It seems like the temperature at which a bearing becomes a problem is the same no matter what the weather.

Because a bearing's normal operating range is not absolute, but relative to the ambient temperture.  What they are looking for is a bearing outside of the normal operating range.  The temperture at which it becomes a problem (fails) may be absolute, that I don't know, but they don't want it to ever get close to there.

[Murphy Siding]

zugmann

 

 

charlie hebdo

Fortunately many others (especially those with power) see a real need to force safety measures on the irresponsible railroads. 

 

 

They didn't seem too concerned last 5 years.  Maybe the next 5? 

 

Silly rabbit. Now it's going to cut in profits and dividends. What's the use of owning congressmen if you can't depend on them to enhance your profitability? Congress can now pass regulations that force everyone involved in the production and shipment of chemicals to up their safety programs. Since the higher costs will affect all the players, no one is at a disadvantage. The end consumers pay higher costs.

[Murphy Siding]

BigJim

 

 

CSX Robert

 

 

mvlandsw

The report mentioned that the Salem detector showed the journal temperature at 103 degrees which did not trigger an alarm. 103 seems low for a journal that was on fire. A person can have a fever higher than that.

 

 

103 degrees over ambient.  I don't know that the journal was on fire.  I know that's what everyone's claiming, but it may just be shooting sparks.

 

 

103° above "ambient" ? Think about that! If the "ambient" was, for example, 50°, then it would be 153°. Not even hot enough to fry spit! Not even enough to start smoking!

 

Why is the measurement compared to ambient temperature and not the actual tempurature? Our area has temps between -30 a and +115. Why would ambient temperature matter? It seems like the temperature at which a bearing becomes a problem is the same no matter what the weather.

[Euclid]

ricktrains4824

 

 

Euclid

 

 

CSX Robert

 

 

BigJim

Not even hot enough to fry spit! Not even enough to start smoking!

 

 

Which is why they didn't get an alarm.  Most people are claiming the bearing is on fire in that video.  As I explained before, I don't think it was, I think it was just shooting sparks.  What it looks like to me is something failed relatively quickly, causing direct metal to metal wear and a massive shower of sparks, that, in that nighttime video, looks like fire.

 

 

 

 

The phrases, "On fire" and "Shooting sparks" seem rather subjective in this context.  The point is the actual temperature, which is what the detectors sense. 

Would't "shooting sparks" be the dropping of molten steel from the melting of the bearing components and the axle?  Molten steel will be around 2,500 degrees F.  Why wouldn't the heat detector have sensed that high temperature?

 

 

 

 

Sparks can occur, and be very visible, at a lot lower temperature than that.

Especially when it's dark.

Actual NTSB report states the bearing temperatures at specific defect detectors passed, were all below the reporting levels until just before it completely failed. (30 miles out, +34 degrees, 10 miles out +103 degrees. Report minimum threshold is +115 difference each side same axle, or any +170 above ambient. Neither detector recorded a big enough number to trigger an alarm. Prior detector 10 miles out was only +103, below the minimum of +115 same axle/+170 any. Defect detector at East Palestine hit +253. With a below 32F ambient temp, this is still under 300F. This set off the defect alarm, and the engineer increased the dynamics at this point.) When the crew finally got the warning, from the East Palestine detector, the engineer increased the dynamic brakes (to avoid adding more heat to the failing bearing, the correct move) but the bearing totally failed before the train could safely stop, creating a derailment, and that derailment triggered the fully-automatic emergency brake application. 

Those sparks may have been visible, at night, or the "night vision mode" on the security camera may have been drastically over-exagerating the actual "naked eye" visible sparks. No way to know if the crew could see 25 car lengths back at any given point even if the sparks were completely visible.

Either way, rotating metal on metal contact can and does create sparks at a much lower temperature than the melting point of 2,500F. (Video evidence indeed shows sparking at the +253 recorded by the last detector, under 300F when ambient temperature is added in.)

And in any case, there was no chance the crew could have prevented this derailment with the known facts as they are. The warning they received occurred way too late. 

 

With metal spars made by grinding, each spark has very little actual heat as measured as BTU’s which are a combination of temperature and mass.  Each spark has very little mass, so their heat content is relatively low, but their temperatures can still be very high.  However that is very short-lived because they are being rapidly cooled as they fly though the air.  So it is very hard to know exactly how well the detector can get a meaningful measure of temperature off of clouds of sparks that are moving away from their source and quickly cooling.  It would be much different than a detector reading a massive object that was hot and emitting a continuous wave of radiant heat. 

 

But sources say that even just sparks from grinding on steel are around 2,000 degrees F.  For example:

 

“People also ask

 

What is the temperature of a metal spark?

 

Measurements of initial spark temperatures and velocities are reported, as well as the evolution of the temperature and velocity along the flight path of the sparks. Observed initial spark temperature in this work mostly ranged within 1500°C to 1700°C. Results show evidence of both melting and oxidation of the sparks.”

 

Also, these grinding sparks are not actually molten steel, as they are pieces carved out of steel that is at room temperature.  They are only heated by their momentary disruption of form as they are dislodged from the parent metal. 

 

But the video at Salem shows sizeable sparks landing on the ground and bouncing.  They appear to be much larger than grinder sparks.  They look like sparks hitting the floor as someone uses a cutting torch which is actually dropping balls of molten steel.  Those sparks will be close to 3,000 degrees F. There temperature will closely resemble the temperature of their source.  Grind sparks do not.

 

Also grinding sparks are small chips knocked off cold metal, whereas failing bearing sparks are caused by friction heating the metal until it softens from heat and is dislodged, or just melts and flows out.    

 

My general conclusion, according to the available evidence shown in the video, is that the Salem detector did not adequately record the heat level to properly assess the condition of the failing bearing.   

 

Even if the car was just emitting dry sparks, their true temperature would have been much higher than a few hundred degrees. 

[tree68]

Here's a short video, unrelated to railroads, that demonstrates proper technique for grinding using a hand tool.

Of note, starting at about 1:00 in the video, is the appearance of the sparks flying off the work.  

Odds are, if you put your hand there, you wouldn't be burned, although the closing shot is rather humorous...

https://youtu.be/wfyvTsw1gXw

 

[ricktrains4824]

Euclid

 

 

CSX Robert

 

 

BigJim

Not even hot enough to fry spit! Not even enough to start smoking!

 

 

Which is why they didn't get an alarm.  Most people are claiming the bearing is on fire in that video.  As I explained before, I don't think it was, I think it was just shooting sparks.  What it looks like to me is something failed relatively quickly, causing direct metal to metal wear and a massive shower of sparks, that, in that nighttime video, looks like fire.

 

 

 

 

The phrases, "On fire" and "Shooting sparks" seem rather subjective in this context.  The point is the actual temperature, which is what the detectors sense. 

Would't "shooting sparks" be the dropping of molten steel from the melting of the bearing components and the axle?  Molten steel will be around 2,500 degrees F.  Why wouldn't the heat detector have sensed that high temperature?

 

Sparks can occur, and be very visible, at a lot lower temperature than that.

Especially when it's dark.

Actual NTSB report states the bearing temperatures at specific defect detectors passed, were all below the reporting levels until just before it completely failed. (30 miles out, +34 degrees, 10 miles out +103 degrees. Report minimum threshold is +115 difference each side same axle, or any +170 above ambient. Neither detector recorded a big enough number to trigger an alarm. Prior detector 10 miles out was only +103, below the minimum of +115 same axle/+170 any. Defect detector at East Palestine hit +253. With a below 32F ambient temp, this is still under 300F. This set off the defect alarm, and the engineer increased the dynamics at this point.) When the crew finally got the warning, from the East Palestine detector, the engineer increased the dynamic brakes (to avoid adding more heat to the failing bearing, the correct move) but the bearing totally failed before the train could safely stop, creating a derailment, and that derailment triggered the fully-automatic emergency brake application. 

Those sparks may have been visible, at night, or the "night vision mode" on the security camera may have been drastically over-exagerating the actual "naked eye" visible sparks. No way to know if the crew could see 25 car lengths back at any given point even if the sparks were completely visible.

Either way, rotating metal on metal contact can and does create sparks at a much lower temperature than the melting point of 2,500F. (Video evidence indeed shows sparking at the +253 recorded by the last detector, under 300F when ambient temperature is added in.)

And in any case, there was no chance the crew could have prevented this derailment with the known facts as they are. The warning they received occurred way too late. 

[zugmann]

charlie hebdo

Fortunately many others (especially those with power) see a real need to force safety measures on the irresponsible railroads. 

They didn't seem too concerned last 5 years.  Maybe the next 5? 

[7j43k]

Euclid

Would't "shooting sparks" be the dropping of molten steel from the melting of the bearing components and the axle?  Molten steel will be around 2,500 degrees F.  Why wouldn't the heat detector have sensed that high temperature?

 

"Sparks" are almost by definition of a small size.

Perhaps because the source of the high temperature is so much smaller than the surrounding field of view.

If it looks at 50 pieces the size of a gnat that are 2500F, how does it process that info, if it even "sees" it?

 

 

Ed

[CSX Robert]

Euclid

The phrases, "On fire" and "Shooting sparks" seem rather subjective in this context.  The point is the actual temperature, which is what the detectors sense. 

Something in a fire is going to get hot a lot faster than something shooting sparks.  I can hold a bolt in my bare hand and grind on it for quite sometime before it gets too hot to hold, but put that bolt in an oil fed fire and it's going to get hot a lot quicker.  A lot of people have claimed it should have triggered an alarm at the Salem hotbox detector because it was "on fire" before it got to it.  Well, if it wasn't on fire, but was just shooting sparks it's going to take longer to heat up enough to trigger an alarm.

Euclid

Would't "shooting sparks" be the dropping of molten steel from the melting of the bearing components and the axle?  Molten steel will be around 2,500 degrees F.  Why wouldn't the heat detector have sensed that high temperature?

The individual sparks may reach that temperature, but they are miniscule particles surrounded by air, I don't know what the non-contact heat sensors they use in hotboxes would see if aimed at them.  If the sparks where emanating from the top or bottom of the bearing, it's also possible that it with the sensor aimed at the height of the bearing itself that it wiouldn't even see them.

[Euclid]

CSX Robert

 

 

BigJim

Not even hot enough to fry spit! Not even enough to start smoking!

 

 

Which is why they didn't get an alarm.  Most people are claiming the bearing is on fire in that video.  As I explained before, I don't think it was, I think it was just shooting sparks.  What it looks like to me is something failed relatively quickly, causing direct metal to metal wear and a massive shower of sparks, that, in that nighttime video, looks like fire.

 

The phrases, "On fire" and "Shooting sparks" seem rather subjective in this context.  The point is the actual temperature, which is what the detectors sense. 

Would't "shooting sparks" be the dropping of molten steel from the melting of the bearing components and the axle?  Molten steel will be around 2,500 degrees F.  Why wouldn't the heat detector have sensed that high temperature?