Strain gauges already exist to measure the pressure between brake shoes and wheels, though the Car Department does not use them nearly as often as they probably should.
Right on the brake shoe is the only place a sensor could be placed to ensure an accurate measurement, the amount of force applied to the brake wheel or lever does not necessarily translate into braking effort if the moving parts are rusty, stiff, or seized (I’ve seen many wheels that won’t turn at all), or if the chain or rigging is disconnected or jammed somewhere underneath the car.
I don’t think a drawbar strain gauge is necessary, one could simply measure the tractive effort produced by the locomotive(s) during the push/pull test.
That’s right; I forgot most modern locomotives can display that via the computer display.
Perhaps there could be a rapidly-accessible screen for ‘brake testing’ that would contain the display together with confirmation that both the automatic and independent were off … and log the result for posterity.
In reality it would just be used as another ‘efficiency test’, I can already see certain supervisors looking at the download and accusing the crew of doing an improper test because they only pulled/pushed for 9.5 seconds instead of the required 10, or other such things (we get downloaded enough already).
The vast majority of the problems with air and handbrake effectiveness could be fixed with proper maintenance, and the proper enforcement of maintenance standards by the regulators. But I’m not holding my breath.
I suspect the railroads won’t be thrilled at the idea of installing brake pressure sensors, just like their reaction to the proposed ECP mandate.
Just to be clear: When I said, “there is no practical way to secure a train and know that it will stay put,” I was using the word “is” to refer to present day practice. I did not mean that the securement solution is simply impossible to achieve. I meant that securement is impossible to achieve with today’s practice.
I am fully aware that there may be a thousand solutions that could make it possible if they were developed and purchased by the railroads. The problem is not a lack of technology or expertise. The problem is that progress in this area has not been pursued by the industry.
But that alone is rather shocking I think, and that is the only point I am making. No way to safely secure a freight train exists in current practice today. You can find the references to that claim in the TSB report on the QNS&L runaway.
We don’t use push/pull for our securement test. It’s release all the air, both train and independent brake. If it moves, it needs more hand brakes. If it doesn’t move, it’s good to go, or good to stay.
Just did this today. 114 car coal train. Conductor tied what he thought was enough. It wasn’t, then he tied some more. Second time was the charm. In addition to the hand brakes on cars and head end locomotive consist, left the train with a 20 lbs set and the PTC Park* feature engaged.
In regards to Euclid about minimum numbers. Instructions have changed every so often. It started with “sufficient number” then progressed to a certain percentage (the percentage depending on track and location) with a minimum of 5 cars on main tracks and sidings. Some yards did, and some still do, have a specific number minimum for tracks within the physical yard. Even with the minimum, whether specific number or percentage, it still required a securement test. Just in case for whatever reason, the prescribed amount didn’t hold.
Now we’re back to a sufficient number and then a securement test. That’s our primary method. There is a secondary method that is to be used where the primary isn’t practical. It involves using a chart, so many brakes for so many tons on specific grades. The steeper the grade, the more tons being left, the more hand brakes. You can be sure the chart will err on the side of overkill.
In the distant past, brakemen/switchmen carried brake clubs to help them apply/release hand brakes. Today’s hand brakes don’t need their use and it’s prohibited to use brake clubs. (Note, there are tools in use called a brake stick, at least ours are, to allow tying hand brakes from the ground. They are not like, nor used like the brake clubs of the past.) The wheels are geared so that maximum force can be appli
We have a version of that called “roll-away protection” in Canada, though our feature is not part of PTC. American units must not have it, or that UP unit wouldn’t have been able to run away earlier this year in Saskatchewan (it was a DP remote, and the crew forgot to set it out when the left it by itself and went to do some switching, so now we aren’t allowed to “save the air” anymore).
The CROR requires that we do a push/pull test whenever equipment is left on a grade, which is practically everywhere.
“Bottling the air” has been a no no for as long as anyone can remember.
“Saving the air” uses the DP remote’s automatic brake valve to maintain the brake application on the train, just like any other lead locomotive. The DP remote will automatically put the train into emergency if it starts moving or detects signs of an unintentional release.
No, it’s 125 lbs. force, not torque, applied to the lever or wheel rim, the resulting torque is a function of the lever length or diameter of the wheel. Internally, the handbrake unit has a gear train to multiply the torque produced and wind up the chain. The manufacturer states the gear ratio acting on the chain, the loco brake designer decides what diameter wheel to chose to get the needed chain force from the 125 lb. force applied. Doesn’t matter how many hands are used to produce the 125 lb. fo
There’s enough of a safety issue trying to set enough brakes, and then get to where the knuckle needs to go, even with the knuckle slung hands-free and near balance center-of-mass, before you even get to starting to make the repair…
Our DP system is capable of having that. I’ve only had a few conductors who have wanted to use that. You have to secure the train, make a 20 lbs set and then place it into set out mode. If the engine is equipped (and not al
It worked the same here, but we were required to use it whenever possible, though not everyone did. Using it did not affect whether or not we were required to apply handbrakes.
We were told to only do it with CN units, it was prohibited if your remote was a foreign unit or one of the ex-BC Rail Dash-9’s. I don’t recall the ex-IC SD70s being on the prohibited list, but they are rarely seen out this way anymore (good riddance).
I believe the DP unit is supposed to dump the air if it detects movement over 1 mph, a rise in brake pipe pressure, a sharp increase in flow, or an emergency brake application on the lead unit. I was in the habit of turning the DP radio breaker off during shop track brake tests or while the Conductor was cutting in the air, to try and avoid an unintentional emergency application on the trailing portion of the train (the remote just thinks it’s in comm loss while you do that).
[quote user=“jeffhergert”]
PTC Park works without the PTC system engaged. The principle is the same. If movement is detected, it dumps the air. When I leave a train unattended, I like using it. I leave a note for the next engineer to remind him/her to shut off the park. There is a banner on the screen that it’s active, but not
Pushing 30 cars that are locked up in emergency seems pretty hard to believe though. And, as far as pumping it up with air before shoving it. Aren’t there rules that prohibit standing inside the guage so near an “unsecured” train? I mean I thought based upon what we hear here that even just slipping under or over a coupling was verboten, unless means to secure the train were employed. “Red Zone” protection I think it is called?
I’m not sure about rules as my railroading experience working around operating equipment was a very short tenure, and almost 15 years ago. Though from that bridge you mentioned after seeing a photo of it. I would do the exact same thing shove off even if part of the train is locked up. Rather risk equipment than a crew member.
Yes, the system works most of the time despite its defects. I suspect that most trainmen just know how to get the job of securement done effectively. Yet the point is they have no specific method or guidance on the process.
The company management just demands that its employees discharge the responsibility of producing successful securement; no matter how many brakes are set in addition to the minimum requirement, and no matter what the grade steepness is, how tightly the handbrakes are applied, and how poorly maintained the handbrakes are. If securement fails for any reason, it is the fault of the employees.
However, regardless of how successful this shoestring system is, the TSB has produced a special report alerting of an alarming increase in runaway accidents. They are urgently calling on all parties to provide solutions to the problem, including the use of chocks and portable derails.
I am completely ignorant, never worked on the railroad a day in my life. But the solution that looks most promising to me would be to have the conductor walk out to the broken knuckle and plug the airline. And arrange for another locomotive to hook up from the rear, pump up the air, and pull the stranded cars off the bridge “backwards”.
Is the boss gonna be annoyed with the request for assistance?