BC train derailment

[Klause]

So... Our trains don't have Westinghouse triple valve brake systems?


If I recall, a drop in pressure slams the brakes on in that system

[tmyrfield]

So... Our trains don't have Westinghouse triple valve brake systems?


If I recall, a drop in pressure slams the brakes on in that system

Producer cars that I have filled were parked with hand brakes applied. to move the car you released the hand brake by either turning the brake wheel(slow) or pulling the lever(fast). to set the brakes again you had to turn the brake wheel the other way to tighten the brake shoes against the steel wheel. It always amazed me that I could get the car rolling
half loaded just by putting your shoulder(not recommended) to the steel wheels when the brakes were off.

[farming101]

So... Our trains don't have Westinghouse triple valve brake systems?


If I recall, a drop in pressure slams the brakes on in that system

True, the brakes slam on as a result of a pressure drop in the supply line, either by operating the control valve or a severed line, but only if the railcar's reservoirs are full.

[sumdumguy]

It seems that people are questioning the reason for parking the unit for 2 hours on a steep grade. There have been several accidents at Field in the past. No one learns from history.

[poorboy]

Can’t fill cars if need air

If the brakes applied with no air, the elevators would not be able fill them (unless a new one that leaves the loco hooked up) and lots of places couldn’t unload them either.

[highwayman]

What allowed the train to start to move after the shift change when the new personal were already on board. If engines were running and train had adequate air pressure why was the engineer unable to brake the train as soon as it started moving. Were procedures missed when shift change occurred.

[helmsdale]

Yes they have the Westinghouse triple valve brake... but even with the engine hooked up, they have no way to replenish the air tanks on the cars when the brakes are applied. Unlike highway tractors, it's a single airline system.

When line pressure is equal to the car air tank pressure, brakes are off.

When line pressure exceeds air tank pressure, they build pressure in the tanks, and brakes are off.

When line pressure is below air tank pressure, and car air tank reservoir applies the brakes. How far line pressure is below tank pressure dictates how hard the brakes are applied.

When air pressure leaks out of the tanks, line pressure has to be further reduced to maintain the same degree of brake application.

If hand brakes are not applied when the engines have made an emergency brake application like they would in that situation, it's only a matter of time before line and tank pressure equalize at zero due to air leaking out of each individual cars brake system, the brakes come off, and you will have a runaway.

[helmsdale]

All that said, the situation could have been avoided if:
1) dismounting train crew had applied the sufficient amount of hand brakes.
2) they had stopped the train for shift change on flat ground in field, rather than on a grade coming off the kicking horse.

[farmaholic]

Pardon my ignorance, but maybe the RailCo likes to use gravity to get the train moving and up to speed again. Kind of an efficiency thing but maybe some procedures were overlooked and there was an unrecoverable loss of braking capacity when they got going again.

I hate guessing or assuming things, I have no idea what caused this accident.

[Wheatking]

From my limited knowledge of trains, but from. What I understand it's a time consuming job to manually apply the brakes on the train, then release them again. Perhaps if they made it easier to apply the brakes, perhaps a battery powered impact to turn the brake wheel might make it faster and easier. Just like most things in life if a job is difficult it may not get done unless forced.

Or else giving the hours of operation a little more leeway so the first crew would of had time to make it to a more appropriate place to switch out.

Seems like applying the brakes manually is difficult as the accidents happen on occasion, so obviously we must find a way to make it easier to do.