5000-series - Updates

[sw4400]

I have always wondered why some people are so concerned about having rapid transit cars shipped by rail. To me the most economical means seems to be boy-low trailers hauled over highways used by CTA contractors .

DH

Well, delivering via rail would be easier in some circumstances.

• 1. Less Truck Drivers needed for the long haul. All you need is a few local drivers to transport the cars to the railyard they'll be shipped from and picked up at for delivery. The freight crew do the rest.
• 2. Alternate routes. If a low-boy needs to divert from their course, they may run into issues(railroad crossings, viaducts). Some low-boy trailers get hung up on railroad crossings depending on grade steepness of the crossing and if the viaducts are too low, the top of the brand new railcar might get ripped clean off if the driver doesn't pay attention or misjudges the viaduct clearance.

[chicagopcclcar]

" Less Truck Drivers needed for the long haul. "

When Silk Road had the contract hauling 2600s for rehab at New York, the same driver took the road for the round trip. They only had two or three trucks. Also, the low-boy is a one person job....loading, road trip, unloading! Skokie usually has man-power helping though. Check my videos.

DH

[briman94]

Shots of #5533-34 thru #5537-38 @ Harrison. #5331-32 are the head cars.

"This is an Orange Line train to 95th!" Your camera sure did a number on that sign on 5538...

[Busjack]

"This is an Orange Line train to 95th!" Your camera sure did a number on that sign on 5538...

You didn't like the contrast?

[peter.pyterek]

Any delivered cars above 5542 yet?

[BusHunter]

#5541-42 is in service on the Red line approaching Clark/Division Nb.

[garmon757]

"This is an Orange Line train to 95th!" Your camera sure did a number on that sign on 5538...

Ugh!!! I hate it!!! :lol:

[briman94]

Just got on a train led by 5307-08 and they sound like they have square wheels. How did they get flat spots so fast? I thought the new motors were supposed to avoid that.

[Busjack]

Just got on a train led by 5307-08 and they sound like they have square wheels. How did they get flat spots so fast? I thought the new motors were supposed to avoid that.

I don't think the motors have anything to do with it, probably bad rails. But maybe you can get Kevin O'Connor back to the wheel lathe.

[briman94]

I don't think the motors have anything to do with it, probably bad rails. But maybe you can get Kevin O'Connor back to the wheel lathe.

I always thought it was the dynamic brakes braking too hard, or the driver slamming on the e-brake too much. Also, I keep seeing this "Kevin O'Connor" reference...guess I'll have to look that up.

EDIT: found it...pretty funny reference.

[MTRSP1900-CTA3200]

I always thought it was the dynamic brakes braking too hard, or the driver slamming on the e-brake too much...

Yeah, the track brakes aren't good on the wheels for some reason.

[chicagopcclcar]

What is a "e-brake"?

DH

[briman94]

What is a "e-brake"?

DH

The emergency brake, which from what I understand is a combination of a track brake (metal that contacts the actual rail), the wheel friction brakes (presumably causing the most damage to the wheels themselves), and full dynamic/regenerative braking.

[BusHunter]

#5541-42 is in service on the Red line approaching Clark/Division Nb.

Here's some shots of #5541-42

[garmon757]

Here's some shots of #5541-42

Yay!!! Pink Line train to Howard!!! :p

[Busjack]

The emergency brake, which from what I understand is a combination of a track brake (metal that contacts the actual rail), the wheel friction brakes (presumably causing the most damage to the wheels themselves), and full dynamic/regenerative braking.

I guess L cars have disc brakes, but they don't act directly on the wheel, but a brake disc, just as disc brakes on a car do not grab the rubber tires. The track brake would only grab the track. Thus, if it sounds like a square wheel, it is very unlikely it is the brakes. Also, those brakes are essentially no different than on any other electric brake car.

The one difference on the 5000s is that instead of the dynamic brakes dumping the electricity (after reversing the motors into generators) into the resisters and creating heat, they dump the electricity back into the third rail. That's under computer control because the train has to be able to stop when going over a third rail gap. However, since it is under computer control, the stop should be smoother, if anything. There were some comments early in the life of the 5000s that operators were stopping short of the platform, maybe because they weren't used to the regenerative brakes, but the brakes shouldn't have the effects you say (unless the track brakes are digging into the rail, causing a bad rail).

[chicagopcclcar]

What you guys need is a person who is employed and works with operating both DC and AC equipment and can explain how brakes function. Otherwise it's a case of the blind leading the blind.

[briman94]

I guess L cars have disc brakes, but they don't act directly on the wheel, but a brake disc, just as disc brakes on a car do not grab the rubber tires. The track brake would only grab the track. Thus, if it sounds like a square wheel, it is very unlikely it is the brakes. Also, those brakes are essentially no different than on any other electric brake car.

The one difference on the 5000s is that instead of the dynamic brakes dumping the electricity (after reversing the motors into generators) into the resisters and creating heat, they dump the electricity back into the third rail. That's under computer control because the train has to be able to stop when going over a third rail gap. However, since it is under computer control, the stop should be smoother, if anything. There were some comments early in the life of the 5000s that operators were stopping short of the platform, maybe because they weren't used to the regenerative brakes, but the brakes shouldn't have the effects you say (unless the track brakes are digging into the rail, causing a bad rail).

I was under the impression that applying the brakes too hard too fast (i.e. quick e-brake at high speed) would lock up the wheel, causing it to grind along the rail and develop a slight flat spot where it was contacting it. I'm not sure if the brakes on any series are strong enough to do that or not but I assumed that the 5000s would have anti-wheelslip measures in the computer.

[chicagopcclcar]

I was under the impression that applying the brakes too hard too fast (i.e. quick e-brake at high speed) would lock up the wheel, causing it to grind along the rail and develop a slight flat spot where it was contacting it. I'm not sure if the brakes on any series are strong enough to do that or not but I assumed that the 5000s would have anti-wheelslip measures in the computer.

What you guys need is a person who is employed and works with operating both DC and AC equipment and can explain how brakes function. Otherwise it's a case of the blind leading the blind.

Still applicable. "birman94", are you employed by CTA?

[briman94]

Still applicable. "birman94", are you employed by CTA?

I wish! I know the basics of operation, but not the specifics of the CTA vehicles themselves, hence why my speculation is purely that, and probably inaccurate :P

[chicagopcclcar]

I wish! I know the basics of operation, but not the specifics of the CTA vehicles themselves, hence why my speculation is purely that, and probably inaccurate

I have to tell you.....you don't know "the basics." You can only learn "basics" by experience. Without the experience you build a set of errors.

[briman94]

I have to tell you.....you don't know "the basics." You can only learn "basics" by experience. Without the experience you build a set of errors.

Maybe I should have said "principles of operation" rather than "the basics." I know how the systems work in principle but I've never operated them so my assumptions are based solely on theory, which is the main point of me asking for clarification here.

[andrethebusman]

Maybe I should have said "principles of operation" rather than "the basics." I know how the systems work in principle but I've never operated them so my assumptions are based solely on theory, which is the main point of me asking for clarification here.

I did actually drive L trains 1977-82, so this is from experience. Flat wheels on the equipment I worked with (6000's thru 2400's) were all caused by a single reason - sliding the wheels. L cars series 2000 to 2600 have four rates of braking, ranging from rather light (P1) to maximum (P4). Unfortunately, CTA practice has been for years to apply brakes at the last possible second to avoid overrunning the station. This means using P4 at each stop. Now, the problem is that in P4 under anything less than ideal conditions (wet rail, snow, salt spray), there is enough pressure being exerted on the disc brake that if the wheels lose their grip on the rail, the brakes will lock up that axle, and cause the wheel to skid. One skidding stop is all it takes and you have a flat spot. 6000's were not given to these problems simply because maximum braking on a 6000 was just not strong enough to lock up an axle, but the newer cars have a lot more braking force and can easily do so.

The problem was that once your train is sliding, the only thing you can do is release the brakes, and go to coast until the wheels catch the rail again, when you can start braking again. But if you have not left yourself enough room to do this, the only thing you can do to avoid rolling thru the station is to let it slide, and stop by slamming down the track brakes. So now not only are you flattening wheels, but also grinding rail. This is why especially on the Ryan, where road salt forms a slippery surface on the railhead, rail at stations had to be replaced about every 10 years. while between stations lasted from 1969 until the general rebuilding a couple of years ago.

[briman94]

I did actually drive L trains 1977-82, so this is from experience. Flat wheels on the equipment I worked with (6000's thru 2400's) were all caused by a single reason - sliding the wheels. L cars series 2000 to 2600 have four rates of braking, ranging from rather light (P1) to maximum (P4). Unfortunately, CTA practice has been for years to apply brakes at the last possible second to avoid overrunning the station. This means using P4 at each stop. Now, the problem is that in P4 under anything less than ideal conditions (wet rail, snow, salt spray), there is enough pressure being exerted on the disc brake that if the wheels lose their grip on the rail, the brakes will lock up that axle, and cause the wheel to skid. One skidding stop is all it takes and you have a flat spot. 6000's were not given to these problems simply because maximum braking on a 6000 was just not strong enough to lock up an axle, but the newer cars have a lot more braking force and can easily do so.

The problem was that once your train is sliding, the only thing you can do is release the brakes, and go to coast until the wheels catch the rail again, when you can start braking again. But if you have not left yourself enough room to do this, the only thing you can do to avoid rolling thru the station is to let it slide, and stop by slamming down the track brakes. So now not only are you flattening wheels, but also grinding rail. This is why especially on the Ryan, where road salt forms a slippery surface on the railhead, rail at stations had to be replaced about every 10 years. while between stations lasted from 1969 until the general rebuilding a couple of years ago.

That was my general theory. I thought the 5000s had electronics in their motor controllers to avoid wheel slip but I guess under some circumstances it still happens.

[artthouwill]

I did actually drive L trains 1977-82, so this is from experience. Flat wheels on the equipment I worked with (6000's thru 2400's) were all caused by a single reason - sliding the wheels. L cars series 2000 to 2600 have four rates of braking, ranging from rather light (P1) to maximum (P4). Unfortunately, CTA practice has been for years to apply brakes at the last possible second to avoid overrunning the station. This means using P4 at each stop. Now, the problem is that in P4 under anything less than ideal conditions (wet rail, snow, salt spray), there is enough pressure being exerted on the disc brake that if the wheels lose their grip on the rail, the brakes will lock up that axle, and cause the wheel to skid. One skidding stop is all it takes and you have a flat spot. 6000's were not given to these problems simply because maximum braking on a 6000 was just not strong enough to lock up an axle, but the newer cars have a lot more braking force and can easily do so.

The problem was that once your train is sliding, the only thing you can do is release the brakes, and go to coast until the wheels catch the rail again, when you can start braking again. But if you have not left yourself enough room to do this, the only thing you can do to avoid rolling thru the station is to let it slide, and stop by slamming down the track brakes. So now not only are you flattening wheels, but also grinding rail. This is why especially on the Ryan, where road salt forms a slippery surface on the railhead, rail at stations had to be replaced about every 10 years. while between stations lasted from 1969 until the general rebuilding a couple of years ago.

Thank you. At least there is one person who can explain things to correct people;s ideas about a subject rather than criticizing those people because they may not know.