Bad train pictures

[Junctionfan]

After checking out what a PTC /PTS, is it cheaper or at least easier to use this than having CTC or ABS signals (maybe CTC)?

[Junctionfan]

After checking out what a PTC /PTS, is it cheaper or at least easier to use this than having CTC or ABS signals (maybe CTC)?

[Overmod]

In my opinion, massively and rather obviously so -- IF you can afford the sizable initial investment (including assurance of NDGPS coverage for the mileage involved AND you retain full rulebook procedure for what happens if the PTC stops working right.

Keep in mind that PTC and CTC are pretty synonymous; the principal operational difference being that CTC is arranged to run remotely, while some of the PTC logic and implementation is distributed (right down to locomotive-control level). PTS is something of a boondoggle, as it's simply a fancy modern version of the old 'automatic train stop' that's GUARANTEED (whatever that means in a world where Murphy and Finagle keep rearing their fearsome heads) to stop a train short of something it should stop short of. Following some of the NAJPTC reports can be rather illuminating.

ABS of course only works for things completing track circuits ahead of you. Excellent technology for about 1908, but the world has moved on somewhat since then. As we've had experts repeatedly point out, these don't substitute a bit for dispatching and train-order control, which is one of the things that PTC should be particularly good at arranging and monitoring continuously and near-optimally.

My current opinion is that all enginemen should carry cab signals and use them at all times, that all engines should be equipped with communications terminals, and that illuminated wayside signals are almost entirely a useless expense. Some of the data-fusion systems I'm currently working on can even replace yard signals to an extent (for purposes of operating trains)

Some of the overhead and systems used for CTC are common to advanced PTC (you still need motorized switches, proper track sensors and circuits, etc.) I strongly believe that you can monitor unbonded sidings, etc. with proper technology, so quite a bit of that sort of expense could be dispensed with and still reap most of the ideal benefits of PTC... but without low-resistance track bonding, you have to use other approaches to monitor things like broken rails.

[Overmod]

In my opinion, massively and rather obviously so -- IF you can afford the sizable initial investment (including assurance of NDGPS coverage for the mileage involved AND you retain full rulebook procedure for what happens if the PTC stops working right.

Keep in mind that PTC and CTC are pretty synonymous; the principal operational difference being that CTC is arranged to run remotely, while some of the PTC logic and implementation is distributed (right down to locomotive-control level). PTS is something of a boondoggle, as it's simply a fancy modern version of the old 'automatic train stop' that's GUARANTEED (whatever that means in a world where Murphy and Finagle keep rearing their fearsome heads) to stop a train short of something it should stop short of. Following some of the NAJPTC reports can be rather illuminating.

ABS of course only works for things completing track circuits ahead of you. Excellent technology for about 1908, but the world has moved on somewhat since then. As we've had experts repeatedly point out, these don't substitute a bit for dispatching and train-order control, which is one of the things that PTC should be particularly good at arranging and monitoring continuously and near-optimally.

My current opinion is that all enginemen should carry cab signals and use them at all times, that all engines should be equipped with communications terminals, and that illuminated wayside signals are almost entirely a useless expense. Some of the data-fusion systems I'm currently working on can even replace yard signals to an extent (for purposes of operating trains)

Some of the overhead and systems used for CTC are common to advanced PTC (you still need motorized switches, proper track sensors and circuits, etc.) I strongly believe that you can monitor unbonded sidings, etc. with proper technology, so quite a bit of that sort of expense could be dispensed with and still reap most of the ideal benefits of PTC... but without low-resistance track bonding, you have to use other approaches to monitor things like broken rails.

[DaveBr]

I thought this was a "stupid Channel">.All these questions are very educational and interesting.Now a question I heard someone talk about so I think it's very interesting
to those of us that don't know and want to learn..When is it they have a flat tire?? Dave Br

[DaveBr]

I thought this was a "stupid Channel">.All these questions are very educational and interesting.Now a question I heard someone talk about so I think it's very interesting
to those of us that don't know and want to learn..When is it they have a flat tire?? Dave Br

[egmurphy]

QUOTE: Mark H.: Today's 78-foot rail is mostly welded, usually right at the mill, into 1500-foot or so lengths...

How does one handle a 1500 foot length of rail? What type of car (or series of cars) is it transported on? Is there specialized equipment to offload / place / spike a length of rail that long?

(I've actually wondered about this for a long time, but since the subject of the rail just came up this seems a good time to ask the question.)

Thanks

Ed

[egmurphy]

QUOTE: Mark H.: Today's 78-foot rail is mostly welded, usually right at the mill, into 1500-foot or so lengths...

How does one handle a 1500 foot length of rail? What type of car (or series of cars) is it transported on? Is there specialized equipment to offload / place / spike a length of rail that long?

(I've actually wondered about this for a long time, but since the subject of the rail just came up this seems a good time to ask the question.)

Thanks

Ed

[egmurphy]

Thanks for the quick reply.

That's an impressive arrangement, and the entire operation must be equally impressive.

Guess I need to use Google more. [:I]

Thanks again,

Ed

[egmurphy]

Thanks for the quick reply.

That's an impressive arrangement, and the entire operation must be equally impressive.

Guess I need to use Google more. [:I]

Thanks again,

Ed

[Willy2]

What I really like about threads like this one is I always learn more than just the answer to the question asked. Thanks!

[Willy2]

What I really like about threads like this one is I always learn more than just the answer to the question asked. Thanks!

[Overmod]

Dave -- a flat wheel occurs when the brakes are applied too firmly and the wheeltread 'skids' on the rail. You can imagine that significant friction will result here, even for a relatively small amount of motion. Even a small 'flat' on a heavily loaded steel wheel will cause high shock forces on the rail (and high localized stress when the 'corners' roll through the contact patch).

Imnsho, the 'correct' way to handle this kind of situation would be to have an appropriate on-car wheel lathe (cf Hegenscheidt, http://www.hegenscheidt-mfd.de/gb/index.htm) in convenient places to treat cars (and perhaps locomotives) that have been 'detected' or otherwise tracked with flat wheels. My impression is that the cost of this equipment hasn't been thought justified for 'interchange' service or repair by the accepting railroads; I'm not sure what would need to happen to get the idea widely enough adopted.

[Overmod]

Dave -- a flat wheel occurs when the brakes are applied too firmly and the wheeltread 'skids' on the rail. You can imagine that significant friction will result here, even for a relatively small amount of motion. Even a small 'flat' on a heavily loaded steel wheel will cause high shock forces on the rail (and high localized stress when the 'corners' roll through the contact patch).

Imnsho, the 'correct' way to handle this kind of situation would be to have an appropriate on-car wheel lathe (cf Hegenscheidt, http://www.hegenscheidt-mfd.de/gb/index.htm) in convenient places to treat cars (and perhaps locomotives) that have been 'detected' or otherwise tracked with flat wheels. My impression is that the cost of this equipment hasn't been thought justified for 'interchange' service or repair by the accepting railroads; I'm not sure what would need to happen to get the idea widely enough adopted.

[Anonymous]

How flat can a wheel be before it needs to be turned and how do the detectors pick them up? The sound and shock of a flat wheel on empty grain car is quite a bit different than a loaded coal car. I assume wheels are softer than the rail - do minor flat spots work themselves out?

[Anonymous]

How flat can a wheel be before it needs to be turned and how do the detectors pick them up? The sound and shock of a flat wheel on empty grain car is quite a bit different than a loaded coal car. I assume wheels are softer than the rail - do minor flat spots work themselves out?

[dehusman]

Actually the machine doesn't really "unload" the rail. You chain the rail to the existing track and pull the train out from under it The machine guides the rail into place on the ground.

The most common detectors for flat wheels have been in service since the 1800's. Ears and eyes. There are new electronic detectors but they are relatively rare (as compared to other detectors). They measure the vertical impact of the wheel on the rail (strain guages).

Dave H.

[dehusman]

Actually the machine doesn't really "unload" the rail. You chain the rail to the existing track and pull the train out from under it The machine guides the rail into place on the ground.

The most common detectors for flat wheels have been in service since the 1800's. Ears and eyes. There are new electronic detectors but they are relatively rare (as compared to other detectors). They measure the vertical impact of the wheel on the rail (strain guages).

Dave H.

[tree68]

We're mostly familiar with how crossings like Rochelle work - first come first serve, all handled by track circuits.

We've also discussed a RR "holding" a crossing for another train.

So, assuming that there are no other movements involved, just how long is it after a train clears the crossing that the other line gets green?

[tree68]

We're mostly familiar with how crossings like Rochelle work - first come first serve, all handled by track circuits.

We've also discussed a RR "holding" a crossing for another train.

So, assuming that there are no other movements involved, just how long is it after a train clears the crossing that the other line gets green?

[CShaveRR]

My speculation would be--assuming, as you do, that no other trains are on the same route, that the signal would clear instantly, once the conflicting movement had cleared the circuit for the home signals.

But maybe I should go investigate this weekend.

[CShaveRR]

My speculation would be--assuming, as you do, that no other trains are on the same route, that the signal would clear instantly, once the conflicting movement had cleared the circuit for the home signals.

But maybe I should go investigate this weekend.

[Anonymous]

Stupid Question - If Amtrak is detoured off its normal route - who takes direct command of the Loco Amtrak?

[Anonymous]

Stupid Question - If Amtrak is detoured off its normal route - who takes direct command of the Loco Amtrak?

[CSSHEGEWISCH]

A lot depends on whether a time lock is also involved or not. Time locks, if used, come into play if a train is delayed while in the approach circuit. The Special Instructions would include a sentence stating to the effect that if a train passes the distant signal and is subsequently delayed, it should approach the home signal prepared to stop.

[CSSHEGEWISCH]

A lot depends on whether a time lock is also involved or not. Time locks, if used, come into play if a train is delayed while in the approach circuit. The Special Instructions would include a sentence stating to the effect that if a train passes the distant signal and is subsequently delayed, it should approach the home signal prepared to stop.

[CSSHEGEWISCH]

On detours, the National Detour Agreement comes into play. The Amtrak engineer may still be operating the locomotive but the host road would provide a pilot to pass information about the road and signals to the engineer.

[CSSHEGEWISCH]

On detours, the National Detour Agreement comes into play. The Amtrak engineer may still be operating the locomotive but the host road would provide a pilot to pass information about the road and signals to the engineer.

[Anonymous]

QUOTE: Originally posted by CSSHEGEWISCH

On detours, the National Detour Agreement comes into play. The Amtrak engineer may still be operating the locomotive but the host road would provide a pilot to pass information about the road and signals to the engineer.

Thanks. I guess its like a ship entering a port.

[Anonymous]

QUOTE: Originally posted by CSSHEGEWISCH

On detours, the National Detour Agreement comes into play. The Amtrak engineer may still be operating the locomotive but the host road would provide a pilot to pass information about the road and signals to the engineer.

Thanks. I guess its like a ship entering a port.