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Unbelievable! 

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On 7/24/2019 at 1:33 PM, CMOP said:

Unbelievable! 

Entirely believable.  Here's why:   

What you need to move a static load is torque, lots of it.  An electric motor has the characteristic of delivering maximum torque at starting rpm. Whatever that starting torque is, you can dramatically multiply that value by using a gear reducer between the motor output shaft and the wheel.  You already have that built inside the differential in a typical pick-up truck.  You can also do the same by installing a planetary gear at the wheel itself.  It will be interesting to find out which approach the Ford engineers used. 

Those rail cars are made with steel wheels, riding on a steel rail.  There is no deformation of steel at the contact point, as there would be with rubber tires.  With a rubber tire, the major use of the engine energy is in the deformation of the tread surface and the re-forming of the shape after the rubber point leaves the flat footprint of the tire on the road.  Tire flex takes up your horsepower, and you have no flex with a railroad.  Trains are typically set up with only one horsepower per ton of loaded weight, while trucks typically use ten horsepower per ton of load.  So a tractor trailer running with 40,000 lbs of cargo will have an engine fitted with 400 hp. in order to maintain 60 mph.  A rail locomotive fitted with a 3,500 hp. engine will be able to pull 3.5 million tons of cargo, which is why you see these trains running with 100 freight cars behind, rolling along at 60 mph across the prairies.  Substitute rubber tires and the locomotive will not budge.  It is all in the wheel material!

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Locomotives have electric motors on each wheel, so a six-axle loco has 6 electric motors powered by a diesel generator. Usually one finds about 4 locomotives pulling 100 cars. 4 x 6 = 24, 100 / 24 = 4, and 4 200,000 pound cars = 800,000 pounds. Of course, these motors have to do this for thousand mile trips. How hard is it to set up a 'demo' in 'perfect conditions' where a similar motor pulls 1.5 x a typical payload in controlled conditions for a single mile a single time?

The first thing this suggests is that someone building an electric truck will have a deep bench of experience from the railroad world - diesel electrics go back to the 1930's.

My landlord (in the late 1990's) brought a load of pea gravel in his F-150 pickup to build a French drain. Seeing what was obviously an overloaded truck, I remarked to him that a cubic yard of water weighs 1800 pounds. It took him a minute to realize why I made that comment - the load in his truck was clearly more than a cubic yard, and it was obviously heavier than water. He remarked that he had a hard time controlling the truck on his way over, the brakes couldn't handle the load.

Demoing something like this is ultimately irresponsible - if truck brakes can barely handle an overloaded truck, just imagine what will happen if someone tries towing a railroad freight car with no brake linkage at all. Youtube makes their money from stupid people performing lethal experiments.

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7 hours ago, Meredith Poor said:

Demoing something like this is ultimately irresponsible - if truck brakes can barely handle an overloaded truck, just imagine what will happen if someone tries towing a railroad freight car with no brake linkage at all. Youtube makes their money from stupid people performing lethal experiments.

And railway cars have auto brakes.... You have to apply power(air pressure) to UNBRAKE them. 

Don't get your information from Hollywood😜

No steel and concrete do not spontaneously explode, nor do gun silencers make a gun silent.

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(edited)

17 hours ago, Jan van Eck said:

Entirely believable.  Here's why:   

What you need to move a static load is torque, lots of it.  An electric motor has the characteristic of delivering maximum torque at starting rpm. Whatever that starting torque is, you can dramatically multiply that value by using a gear reducer between the motor output shaft and the wheel.  You already have that built inside the differential in a typical pick-up truck.  You can also do the same by installing a planetary gear at the wheel itself.  It will be interesting to find out which approach the Ford engineers used. 

Those rail cars are made with steel wheels, riding on a steel rail.  There is no deformation of steel at the contact point, as there would be with rubber tires.  With a rubber tire, the major use of the engine energy is in the deformation of the tread surface and the re-forming of the shape after the rubber point leaves the flat footprint of the tire on the road.  Tire flex takes up your horsepower, and you have no flex with a railroad.  Trains are typically set up with only one horsepower per ton of loaded weight, while trucks typically use ten horsepower per ton of load.  So a tractor trailer running with 40,000 lbs of cargo will have an engine fitted with 400 hp. in order to maintain 60 mph.  A rail locomotive fitted with a 3,500 hp. engine will be able to pull 3.5 million tons of cargo, which is why you see these trains running with 100 freight cars behind, rolling along at 60 mph across the prairies.  Substitute rubber tires and the locomotive will not budge.  It is all in the wheel material!

I used to race road bicycles and spent a fortune on delicate race tires. Sidewalls with higher thread counts than my sheets!

Pro level indoor track wheels are made with silk and latex and need to be carried around in a bag they are so delicate - but fast, insanely fast.

https://a-dugastusa.com/products/piste-latex-cotton-track-tubular-tire

Edited by Enthalpic
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3 hours ago, Wastral said:

And railway cars have auto brakes.... You have to apply power(air pressure) to UNBRAKE them. 

Don't get your information from Hollywood😜

No steel and concrete do not spontaneously explode, nor do gun silencers make a gun silent.

Front end loaders push railcars around all the time. Usually there is a brakeman on the car to stop it in such circumstances. The brakes are on when the car is uncoupled, but they can be overpowered with enough force. I'm sure in this demo the brakes were released. Maybe there was a compressor in the back of the truck.

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On 7/27/2019 at 11:39 AM, Jan van Eck said:

Entirely believable.  Here's why:   

What you need to move a static load is torque, lots of it.  An electric motor has the characteristic of delivering maximum torque at starting rpm. Whatever that starting torque is, you can dramatically multiply that value by using a gear reducer between the motor output shaft and the wheel.  You already have that built inside the differential in a typical pick-up truck.  You can also do the same by installing a planetary gear at the wheel itself.  It will be interesting to find out which approach the Ford engineers used. 

Those rail cars are made with steel wheels, riding on a steel rail.  There is no deformation of steel at the contact point, as there would be with rubber tires.  With a rubber tire, the major use of the engine energy is in the deformation of the tread surface and the re-forming of the shape after the rubber point leaves the flat footprint of the tire on the road.  Tire flex takes up your horsepower, and you have no flex with a railroad.  Trains are typically set up with only one horsepower per ton of loaded weight, while trucks typically use ten horsepower per ton of load.  So a tractor trailer running with 40,000 lbs of cargo will have an engine fitted with 400 hp. in order to maintain 60 mph.  A rail locomotive fitted with a 3,500 hp. engine will be able to pull 3.5 million tons of cargo, which is why you see these trains running with 100 freight cars behind, rolling along at 60 mph across the prairies.  Substitute rubber tires and the locomotive will not budge.  It is all in the wheel material!

This is all smoke & mirrors as both Jan and Meredith have pointed out and explained in laymen's terms.

Wastral appears to be in 'publish or perish' mode again.

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On 7/27/2019 at 7:46 PM, Meredith Poor said:

Front end loaders push railcars around all the time. Usually there is a brakeman on the car to stop it in such circumstances. The brakes are on when the car is uncoupled, but they can be overpowered with enough force. I'm sure in this demo the brakes were released. Maybe there was a compressor in the back of the truck.

There is an air tank underslung under the freightcar frame, and valving that allows for the air to either lock or unlock the wheel brakes.  The locomotive air compressors send fresh air via hoses to the tanks to keep them pressurized.  When the freightcar "sits" for some hours on a siding, eventually the air will leak out of the holding tank and the springs on the standing brake actuator circuits will release the cars, in theory. In practice an uncoupled car will have enough air in it, possibly for a few hours, to keep it locked, so the cars have these antique-system chainwheels with a long chain running down to a turnwheel directly to the actuator, and the brakeman goes from car to car chaining down the brakes to chain down the string of cars.  In practice, railway workers are known to be slovenly and not chain down the requisite number of cars at a stop, using the service brakes and the engine compressor to hold the train.  If the compressor quits, then the engine and string will have the brakes released, and the entire train will become a runaway, wrecking at some point.  To get past this, passenger trains have a two-pipe air system, while the freights still run on the same system of one pipe developed by George Westinghouse back in the Stone Age. The reliance is on the manual chainwheel, which reliance is misplaced. 

Since it is a royal pain to chain down an entire string of 100 cars, a more logical improvement would be to have an electric motor crank that chainwheel, all controlled by a command station.  You push a button and all the chainwheels spin and lock the brakes.  I developed such a system but have yet to finish up patenting it.  Railroads are notoriously mired in the past; innovation is achingly slow.  So you have these practices from the 1800's still around today. 

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On 7/31/2019 at 11:19 AM, Jan van Eck said:

There is an air tank underslung under the freightcar frame, and valving that allows for the air to either lock or unlock the wheel brakes.  The locomotive air compressors send fresh air via hoses to the tanks to keep them pressurized.  When the freightcar "sits" for some hours on a siding, eventually the air will leak out of the holding tank and the springs on the standing brake actuator circuits will release the cars, in theory. In practice an uncoupled car will have enough air in it, possibly for a few hours, to keep it locked, so the cars have these antique-system chainwheels with a long chain running down to a turnwheel directly to the actuator, and the brakeman goes from car to car chaining down the brakes to chain down the string of cars.  In practice, railway workers are known to be slovenly and not chain down the requisite number of cars at a stop, using the service brakes and the engine compressor to hold the train.  If the compressor quits, then the engine and string will have the brakes released, and the entire train will become a runaway, wrecking at some point.  To get past this, passenger trains have a two-pipe air system, while the freights still run on the same system of one pipe developed by George Westinghouse back in the Stone Age. The reliance is on the manual chainwheel, which reliance is misplaced. 

Since it is a royal pain to chain down an entire string of 100 cars, a more logical improvement would be to have an electric motor crank that chainwheel, all controlled by a command station.  You push a button and all the chainwheels spin and lock the brakes.  I developed such a system but have yet to finish up patenting it.  Railroads are notoriously mired in the past; innovation is achingly slow.  So you have these practices from the 1800's still around today. 

We try to learn from mistakes.

https://en.wikipedia.org/wiki/Lac-Mégantic_rail_disaster

The TSB estimated that somewhere between 17 and 26 hand brakes would have been needed to secure the train. Had there been a two-man crew, they would have been able to perform a stabilization test, by releasing all air brakes and ensuring just the hand brakes would hold the train. Since there was only a one-man crew this test was not possible.

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2 hours ago, Enthalpic said:

We try to learn from mistakes.

https://en.wikipedia.org/wiki/Lac-Mégantic_rail_disaster

The TSB estimated that somewhere between 17 and 26 hand brakes would have been needed to secure the train. Had there been a two-man crew, they would have been able to perform a stabilization test, by releasing all air brakes and ensuring just the hand brakes would hold the train. Since there was only a one-man crew this test was not possible.

There is a lot more to it than that.  First, there was no logical reason for the personnel transfer to happen 7 miles outside town and at the top of the grade,  There is a rail yard at the bottom, in the town, where the hand-off should have been made.  Second, the train was left on the mainline, and the double-ended passing siding was occupied by surplus empties intended for the wood mill in town.  Those should have been stored somewhere else, on a freight siding in town or at the plant.  Third, the driver should not have left the train until his replacement arrived. 

What those guys did was adopt the practice of chaining nothing (as a courtesy to the next crewman, who would otherwise have to un-chain them all) and leaving the engine in service emergency brake air position in the control cab, thus locking the brakes with service air.  This went wrong because the running engine had a hold blown intothe top end of one piston, thus sucking crankcase oil out into the combustion chamber and burning it partially, with the result that "fire" came out the stack and the area around it was showered with unburned oil droplets.  Someone saw the sparks coming out the stack, called the fire dept, and those guys came along and shut off the motor.  That stopped the sparks, but because the local firemen (volunteer farmers) had no idea how the air brakes worked, they did not understand that shutting off the motor also meant the replacement air to the brakes was also shut off, and then the brake pistons started bleeding down.  When enough air escaped, took about an hour, then the train started rolling downhill.

I was asked by a rail safety symposium to study the aftermath and make recommendations.  I observed that if the RR had installed a stub switch with about ten feet of track, then a bumper stop, on the siding, and the train was parked on the siding switch, then if the air was lost, all it would do was roll gently forward a few feet and hit the bumper, thus stopping the train.  So for about $50,000 this huge wreck occurred.

Also to be mentioned was that the driver was late 40's, divorced and living with his mother.  Obviously that crimped his sexual life.  It was Friday evening and the women in town, either volunteer or paid, were ready and waiting.  You already know how that goes.  He is not about to miss his Friday night rendezvous with some willing woman by waiting around for the replacement motorman to show up  (and that fellow finally arrived at 2 AM, an hour late and a dollar short, with the fires in full swing in the town).  

The RR was owned by a friend of mine, a fellow from Yale who had bought it out of bankruptcy court.  Well, it went back into bankruptcy court and got sold off in two pieces to a rail conglomerate.  I wanted to buy it from the Court but no way I could put together enough cash in competition with a hedge fund with a few billion behind them.  So, now those guys run it - but with 2-man crews. 

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On 7/27/2019 at 7:46 PM, Meredith Poor said:

Front end loaders push railcars around all the time. Usually there is a brakeman on the car to stop it in such circumstances. The brakes are on when the car is uncoupled, but they can be overpowered with enough force. I'm sure in this demo the brakes were released. Maybe there was a compressor in the back of the truck.

RR freight cars typically run on the single-pipe system.  There is this air tank slung underneath the freightcar, and it is attached to the incoming pressure line from the locomotive and to the brake piston by what is called the "triple valve."  In operation, first the underslung tanks are all pressurized from the loco tanks and compressor.  Then when you want to stop, the engineer up  front pushes the airbrake handle over, and exhausts some air out of the pressure line.  That differential, between tank pressure in that car tank and the brake-line tank, in turn moves the ports open to allow the tank air to actuate the brake piston.  As each car has its own tank, not connected directly, as long as there is reserve air in the tank the brakes will stay applied.

Eventually the tank air will "bleed out" due to small air leaks in the system.  When the air is finally exhausted then the brake pistons free up and the car can be moved around with a push machine.  In train service, the pistons are released when the engineer resets the brake controller handle to supply fresh compressed air to the main pipe, which moves the ports around in the triple valve to open the air tank to the main pipe (thus allowing the tank to fill back up) and simultaneously lets the trapped piston air escape to the outside, thus releasing the pistons.  

The bugaboo is if the engineer fans the brakes on a downgrade, continuing to pressurize the brakes (thus dropping tank pressure) and releasing, but not having enough time to fully charge those tanks.  As the triple valve works on pressure differentials, you can ratchet down the system pressure to the point where there is not enough air left to fully apply the brake pistons, and you have a runaway train.  You could try to stop the runaway by climbing up the freight cars and manually chaining down each car, but if you slip then you are crushed to death, so the crew typically jumps off and the train heads to oblivion.  Nothing like a hundred-car wreck on the downgrade to make your day. 

P.S.  No need for a compressor.  Just exhaust the tanks and the cars will roll freely. That is why all parked cars have to be fully chained shut, each time. 

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