NTSB is saying a bad wheel bearing caused the big derailment that recently happened in Ohio and has release some video where you can possibly spot it before the derailment. The video is linked into this news story. Pretty interesting stuff https://www.msn.com/en-us/news/us/n...f97cd8f364ac04260&ocid=winp2fptaskbarhoverent
I grew up not far from there, and much of my extended family lives in nearby towns. The environmental contamination is my biggest concern. Ground and surface water, air and soil contamination. This area is rural farmland, and in the Ohio River watershed. The chemicals involved are nasty enough by themselves, but their decomposition products (from the fire) are even worse. Other notable accidents involving vinyl chloride include the Paulsboro, NJ 2012 derailment. https://www.ntsb.gov/investigations/AccidentReports/Reports/RAR1401.pdf Preliminary NTSB report: https://www.ntsb.gov/news/press-releases/Pages/NR20230214.aspx
I wonder if there are working detectors along that line? From what I have been able to find, it sure sounds as though there were a few large errors made in this entire process. i am thinking that we will be hearing from lawyers, very soon.
There is a railroad signalman from that territory that posts on another forum. He says there were two detectors close to the derailment site - one in East Palestine almost next to the accident. Based on the detector types he's not sure it would have been detected except right before the accident as his analysis of the videos that are on the interwebs leads him to believe it was a stuck brakeshoe heating the axle that caused the problem. Assuming the NTSB does its usual thorough job we will know soon enough. Certainly enough bad stuff to watch out for, and both state and federal environmental regulators are monitoring. Agreed the decomposition products are nasty stuff, but not sure how else they could have been handled.
The detectors NS uses--if there is a defect, is it immediately alerted or does it scan the whole train and alert after the last car clears it? I don't know how they're supposed to work.
Detectors give an alert tone when a defect is detected, but don't give you the defect until the "Train Summary" message after the train clears the detector. If it's a bad defect, the detector also will say "Critical Alarm".
Another point about detectors. They are all interconnected back to a mainframe computer. Every train's passage is compared from detector to detector for "trends". If it is noticed that a bearing is running a little warmer at each detector, a "trending alert" message goes out to Mechanical or Operations. This usually results in the dispatcher telling a crew to set a car out, regardless of if it has actually triggered a detector. Keep this info in mind for future reference... I don't remember what the trigger temperature is for a "hotbox", but 250 or 350 degrees sticks in my head.
Alright, everyone, this thread is starting to delve into political topics. Please stop bringing politics into this forum. As per our forum policy:
When it comes to dealing with HAZMAT incidents where the lading has been breached and is on fire. There are only two possible decisions. Bad and Worse. There are no Good decisions when dealing with HAZMAT, if there were Good decisions it would not be HAZMAT. At our vantage point, we do not have the data upon which the Decision Maker(s) made their decisions.
Agreed. Once HAZMAT is involved, fires make bad situations worse. The polymerization explosion hazard is one thing, but any sealed vessel (tank car), when heated sufficiently begins to boil the lading. When sufficient pressure builds, safety devices intended to release excessive pressure cannot cope with the accelerated vapor production, and the vessel violently fails. This is called Boiling Liquid Expanding Vapor Explosion, or BLEVE. Firefighters are specifically trained to identify and safeguard against BLEVE hazards in a fire. If the lading is flammable, a huge fireball ensues along with the incredible explosive forces, placing large areas in danger. Explosion fragments can travel a mile or more. https://en.wikipedia.org/wiki/Boiling_liquid_expanding_vapor_explosion
One thing many MAY have to come to grips with - There may not be any single individual or action upon which to place the INSTANT responsibility. Just like one can't apply personal responsibility for the Turkey/Syria Earthquakes or the Tsunami that damaged Japan and the Fukishema reactor. The HBD's responded in the manner they were expected to with the readings they saw. The crew responded in the manner they were expected to after getting their Critical Warning. Nobody responded to the sighting of Icebergs by ordering Full Speed Ahead.
The non-rail in me asks the ones who do know, how does a car knocker identify a bad bearing during a car inspection before departure? Bad wheels (shelling, cracking, etc) are identifiable during visual inspection, but what about worn bearings? Are there visual cues that an inspector could identify if a bearing was worn badly? Like mmi16 noted, there may not be a single individual on which to place sole blame; but rather a failure that could not be prevented.
An experienced car knocker will look for discoloration, loss of the internal grease by the seals failing, cracks and other little things I don't remember. Also, when they still did this, two would watch each train leave and listen and observe the wheels and bearings. A failing bearing will fairly shout at them as they do the roll by inspection. These roll by inspections were an important duty that guys bid for at various locations. But, they have been replaced by the electro box.
If it's anything like a car bearing that I deal with on a regular basis, like badlandnp said-all the above, plus usually you can smell it pretty good too.
When you are 23 cars and two engines ahead of the failing bearing - it is tough to get a whiff of the burning lubricant as you are moving along at track speed. All the coulda, woulda, shoulda will not change what actually happened. The best thing that can happen is for some 'new insight' into the failure mode of railroad roller bearings to be learned. While I can hope for that, I will not be holding my breath. Roller bearing have been failing ever since they started to be used on freight cars in 1954. They fail much more infrequently than did the 'plain babbet' bearings that moved railroads from their infancy to 1954, to the point that plain bearing were outlawed from Interchange service for HAZMAT cars in 1991 and for all cars in Interchange service in 1994. Plain friction bearings can be used on individual carriers IF, and it is a big IF, they allow their use in some circumstances.
Other than the discoloration or leakage noted above, the short answer is they can't. It is a sealed bearing, they can't see inside if it without completely disassembling the truck and bearing. The bearings can be failing badly and show no visible sign, it's all internal damage. Plus all the methods of detecting a bad bearing rely on the bearing to be moving, other than disassembly leakage or discoloration, there is no test for a static bearing. There are now three methods for detecting bad bearings, the oldest and least precise is temperature (the bearing overheats), the next is acoustic (the bad bearing makes noises) and the new method is vibration (the bad bearing "shimmies"). The vibration method is still being developed and is just a proposal so far. Roller bearing also can fail fast when they do go. It can take a long time for the bearing to reach a critical point, but once it does it can fail in 20 miles or less. The good news is that overall the roller bearing is a huge improvement and much safer than plain bearings they replaced. It's not perfect, but it is waaaaaay better than plain bearings.
The problem is that on a train, there is a strong "hot metal" smell already from the brake shoes. And with a sealed bearing the grease may not leak until catastrophic failure.
Here is a paper on the vibration method which looks very promising. https://link.springer.com/article/10.1007/s40534-020-00230-x
