The report says four cylinders per truck. I am not familiar with that detail design but hesitate to call them liars. I suspect the design is related to the three-piece construction.
Regarding this QNS&L runaway, I see the following points in play:
Poorly maintained air brake cylinders left them unable to hold pressure to maintain their application force.
Poorly maintained hand brakes left them unable to provide clear operational feedback to the person applying them, and unable to provide application force that matches the application force indicated by the operational feedback.
Even with perfectly operational handbrakes providing application force matching the feedback to the person setting them, there is no way to know for sure whether the person applying them is using enough manual force to make them fully effective.
There are also no set criteria or rules specifying how many properly set handbrakes in good operating condition are required to assure the train is secured from possible movement.
There is no effective test to determine whether the number of handbrakes set will be sufficient to assure the train is secured from possible movement.
The technology of freight train brakes is essentially frozen due to upgrades needing to be compatible with all non-upgraded cars in the national loose car pool.
While the brake technology is frozen, the performance needs for braking have increased due to trains becoming longer and heavier. The ability to compensate
Does it? C&P from the report:
I read that as four cylinders per car.
I completly agree with you with the additional thought that with the current emphisis on reducing Operating Ratio pushing management to “cut costs”, attention to maintenance and repair is reduced so the probability of more events like these seems inevitable.
You can see on Google Maps, views of it.
No it implies that, but does not say that. It says, "LIM cars are equipped with truck mounted brakes that consist of four cylinders.
That could mean four cylinders per truck, but I believe it actually means two cylinders per truck, four total on the car. Each cylinder operating a brake beam for an individual wheelset on the trucks.
Jeff
[quote user=“Euclid”]
Regarding this QNS&L runaway, I see the following points in play:
Poorly maintained air brake cylinders left them unable to hold pressure to maintain their application force.
Poorly maintained hand brakes left them unable to provide clear operational feedback to the person applying them, and unable to provide application force that matches the application force indicated by the operational feedback.
Even with perfectly operational handbrakes providing application force matching the feedback to the person setting them, there is no way to know for sure whether the person applying them is using enough manual force to make them fully effective.
There are also no set criteria or rules specifying how many properly set handbrakes in good operating condition are required to assure the train is secured from possible movement.
There is no effective test to determine whether the number of handbrakes set will be sufficient to assure the train is secured from possible movement.
The technology of freight train brakes is essentially frozen due to upgrades needing to be compatible with all non-upgraded cars in the national loose car pool.
While the brake technology is frozen, the performance needs for braking have increased due to trains becoming longer and
Recall that there are two types of hand brake “activators.” There are brake wheels, as noted, and there are levers. A calibrated brake club would have to be able to measure both.
Then there is the question of how much torque is enough. It may well vary by type of car, and how much of an application is on the brake pipe.
If I crank away at the lever on our passenger cars, with the brakes released, I can pull until I can’t any more, and that’s quite a bit. If the engineer then sets the brakes, I can usually get a couple more pulls in.
The same is true on our cars with brake wheels.
Retrofitting such a measuring device on every car not only introduces the cost of the installation, but the cost of the maintenance. Then we’re into cost vs benefit.
Another idea along those lines would be for train crew to use an electric impact/torque wrench?
I am probably telling people around here stuff that they already know, but I bought a “breaker bar” in order to loosen bolts on a brake caliper frame in order to change brake rotors on a car, and I am figuring I am going to need a lot more torque than that if I take on the challenge of changing the rear struts on an old car that is bouncing pretty good.
An air tool impact wrench would be the next step up, and a biochemist turned computer support guy at the U who works on his own cars told me “get yourself a good air compressor”, but I have a neighbor whose son works professionally as an auto mechanic who showed me an electric impact wrench he uses for fixing his Dad’s pickup truck.
A heavy-duty electric impact wrench runs at least several hundred dollars so I am holding off on getting one until I really need it. But a breaker bar looks like it has more mechanical advantage than a brake wheel, and one of those gee-whiz lithium battery super-powerful permanent magnet electric motor impact wrench has specs that outdo my 36" breaker bar?
So yes they are expensive, and yes you have to keep a battery charged, but would one of those hand-held electric impact wrenches with a torque setting be the thing to crank down brake wheels?
The other thing about these impact wrenches is that they have some kind of mass-reaction thing in them that you don’t need to be exceptionally strong to use one, or at least so they tell me. They also apply rapid hammer pulses that they free up stuck bolts?
Would this work on a creaky brake wheel?
In a word - NO
A impact wrench would be attempting to apply torque at the point that is least effective to transmit that torq
Most truck-mounted air brakes have two opposing pistons, though some designs could be different.
Also of note, on most of these cars the handbrake only applies on the B-end truck, as there is no brake rigging linking the two trucks together. So even if those 35 handbrakes were working properly they might have only given half the braking effort expected by the engineer.
I wonder how many cars leaked off before the engineer applied their handbrakes?
Overmod - Carmen doing air tests from inside a moving vehicle has been a issue for years, the Companies say it is ok and Transport Canada lets them get away with it. But in my experience those “brake tests” are about as accurate as one would expect.
One service unit (division on other railroads) put out in their site specific securement instructions that those type airbrake system counted as 1/2 car. So if the instructions specified that a particular train would need 7 handbrakes and all you had were these types of cars, you would need to apply 14 handbrakes to meet the requirement.
Thservice unit my home terminal was on didn’t have that 1/2 car specification. We were merged into the SU that did, with them taking control. Their instructions now ruled us, too. I attended a safety class where I mentioned this fact because a lot of people weren’t aware of the change or requirement. Including a couple of local officers in attendence.
Me and my big mouth. Now I gave the company officers something else to check crews on when doing securement checks on tied down trains.
Jeff
[quote user=“BaltACD”]
Paul Milenkovic
Another idea along those lines would be for train crew to use an electric impact/torque wrench?I am probably telling people around here stuff that they already know, but I bought a “breaker bar” in order to loosen bolts on a brake caliper frame in order to change brake rotors on a car, and I am figuring I am going to need a lot more torque than that if I take on the challenge of changing the rear struts on an old car that is bouncing pretty good.
An air tool impact wrench would be the next step up, and a biochemist turned computer support guy at the U who works on his own cars told me “get yourself a good air compressor”, but I have a neighbor whose son works professionally as an auto mechanic who showed me an electric impact wrench he uses for fixing his Dad’s pickup truck.
A heavy-duty electric impact wrench runs at least several hundred dollars so I am holding off on getting one until I really need it. But a breaker bar looks like it has more mechanical advantage than a brake wheel, and one of those gee-whiz lithium battery super-powerful permanent magnet electric motor impact wrench has specs that outdo my 36" breaker bar?
So yes they are expensive, and yes you have to keep a battery charged, but would one of those hand-held electric impact wrenches with a torque setting be the thing to crank down brake wheels?
The other thing about these impact wrenches is that they have some kind of mass-reaction thing in them that you don’t need to be exceptionally strong to use one, or at least so they tell me. They also apply rapid hammer pulses that they free up stuck bolts?
Would this work on a creaky brake wheel?
[quote user=“Paul Milenkovic”]
BaltACD
Paul Milenkovic
Another idea along those lines would be for train crew to use an electric impact/torque wrench?I am probably telling people around here stuff that they already know, but I bought a “breaker bar” in order to loosen bolts on a brake caliper frame in order to change brake rotors on a car, and I am figuring I am going to need a lot more torque than that if I take on the challenge of changing the rear struts on an old car that is bouncing pretty good.
An air tool impact wrench would be the next step up, and a biochemist turned computer support guy at the U who works on his own cars told me “get yourself a good air compressor”, but I have a neighbor whose son works professionally as an auto mechanic who showed me an electric impact wrench he uses for fixing his Dad’s pickup truck.
A heavy-duty electric impact wrench runs at least several hundred dollars so I am holding off on getting one until I really need it. But a breaker bar looks like it has more mechanical advantage than a brake wheel, and one of those gee-whiz lithium battery super-powerful permanent magnet electric motor impact wrench has specs that outdo my 36" breaker bar?
So yes they are expensive, and yes you have to keep a battery charged, but would one of those hand-held electric impact wrenches with a torque setting be the thing to crank down brake wheels?
The other thing about these impact wrenches is that they have some kind of mass-reaction thing in them that you don’t need to be exceptionally strong to use one, or at least so they tell me. They also apply rapid hammer pulses that they free up stuck bolts?
Would this work
A feature like found on a torque wrench that clicks when the proper torque is attained is definitely the key feature that is missing from railcar hand brakes. I would speculate that there are hundreds of patents on just such a feature. Without such a “set” indicator, the task is left to the operator, and the tighter the set, the more work the securement is.
I believe there is a torque spec of 125 ft. lbs. That might be even mentioned in the TSB report of the QNS&L runaway. But if a person is given no means of knowing what force they are applying, nothing is holding their feet to fire to sufficiently tighten the brake. And people are inclined to not work any harder than they have to. Anyone can look at the car and see that a hand brake is applied, but nobody can look at it and tell how tightly it is applied.
So there are two problems concerning setting of handbrakes:
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The need to have the brake mechanism properly maintained.
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The need to apply
As I stated earlier in this thread, the design is based on 125 lbs. force applied to rim of the handwheel or for lever type brakes, the gripping point on the lever. The designer has a range of lever lengths or hand wheel diameters, plus the gear ratio of the handbrake mechanism to translate that 125 lbs. force to sufficient force on the shoes to hold the car or loco on a 3% grade.
A problem using an impact wrench to provide the torque is that it beats the crap out of the gearing and bearings in the handbrake unit.
Dave
125 foot pounds by applying both hands to a 15 inch wheel?
That is like trying to remove a stuck lug nut with a “star” lug wrench. Is there a fitness requirement for serving on a train crew?
That is why I know carry a breaker bar in my trunk with an impact socket sized to the lug nut of the car I am driving. With a breaker bar, I can put my 190 pounds of bone, muscle and flab into it, generating over 500 foot pounds if needed. I don’t think I could ever crank on a 15 inch brake wheel to reach 125 foot pounds.
By the way, there are numerous Internet posts on a thing called a “torque” multiplier – it works when a breaker bar fails. It does not involve hammering impacts, but it uses a gear reduction. It does, however, require a fulcrum for its rea
As I mentioned, as incredible as it may seem, there is no practical way to secure a train and know that it will stay put. This makes my point about using Civil War era technology in 2020. This is due the following:
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No way to know how much torque is being applied.
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No way to know if brake is working properly to transmit the torque applied.
-
No way to test the securement once applied.
-
No way to know how many properly applied brakes it takes to rel
[quote user=“Euclid”]
As I mentioned, as incredible as it may seem, there is no practical way to secure a train and know that it will stay put. This makes my point about using Civil War era technology in 2020. This is due the following:
-
No way to know how much torque is being applied.
-
No way to know if brake is working properly to transmit the torque applied.
-
No way to test the securement once applied.
-
No way to know how many properly applied brakes i
There are actually quite a number of methods; the difficulty is in finding one that works reliably in all weather, with ‘typical’ or no maintenance, and that lets you know passively when it’s set.
[/quote]
I am not quite certain why there was not a parallel or codicil to the Power Brake Law that formalized systems of securement brake. Certainly it’s within the Government ‘remit’ of safety, and even something like a yearly requirement to check lubrication and adjustment would have solved most of the securement-related issues. A good law would also clarify things like whether ‘a handbrake’ is all eight wheels on a car without foundation braking, or whether braking should be measured by truck or axle in versions of the ‘tables’ so far written in blood. Perhaps this ought to be low-hanging fruit for a Biden FRA; had I applied for that Director of Safety job a couple of months ago, it might be an early priority…
A simple handheld test gage (a couple of strain gages in a curved frame would do it) applied between wheel and shoe gives a direct reading of applied pressure; comparably instrumented gloves will give a direct pull reading whether wheel or lever, and also ‘catch’ some forms of gearbox or ratchet damage over the range of application. If we add power application to a gearbox, a simple torquemeter arrangement does the same with added precision related to device position, and would allow more cars to be inspected per hour with much lower fatigue than winding on. Scan in the car number and any related data and you have a quick and easy test