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Classification yards - new switch system

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  • Member since
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Classification yards - new switch system
Posted by IslandMan on Saturday, August 5, 2017 7:28 AM

An updated form of the old stub switch concept has been proposed. See the link below and the video within it:

http://www.lboro.ac.uk/enterprise/repoint/technology/

Whatever the merits (or otherwise) of the system for general rail use, it occurs to me that it might be useful in classification yards because:

(i) More routes can lead from each switch compared to conventional blade switches (a characteristic of stub points in general);

(ii) The operating speed of the new design is higher than that of conventional switches.

For (i) the potential advantage would be that the fan of sidings in a yard could be shorter and simpler than in a yard with conventional switches, for a given number of destinations and trains.

For (ii), the effect should be an increase in the speed with which cars being sorted are moved.

Potentially, the land take for a classification yard should be less than with existing systems, and the time taken to sort a train reduced. The number of switches should be less, saving on capital and maintenance costs.

 

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Posted by Euclid on Saturday, August 5, 2017 7:54 AM

 

The stub points lift and drop back down as they shift positions.  Why do they need to lift up?  Why can’t they just shift laterally without lifting and falling?     

 

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Posted by BaltACD on Saturday, August 5, 2017 8:09 AM

IslandMan

An updated form of the old stub switch concept has been proposed. See the link below and the video within it:

http://www.lboro.ac.uk/enterprise/repoint/technology/

Whatever the merits (or otherwise) of the system for general rail use, it occurs to me that it might be useful in classification yards because:

(i) More routes can lead from each switch compared to conventional blade switches (a characteristic of stub points in general);

(ii) The operating speed of the new design is higher than that of conventional switches.

For (i) the potential advantage would be that the fan of sidings in a yard could be shorter and simpler than in a yard with conventional switches, for a given number of destinations and trains.

For (ii), the effect should be an increase in the speed with which cars being sorted are moved.

Potentially, the land take for a classification yard should be less than with existing systems, and the time taken to sort a train reduced. The number of switches should be less, saving on capital and maintenance costs.

I don't see the claimed benefits and only see increased costs.  From the wording in the brochure it appears that it has yet to be installed at any real world location, even on a test basis.  Raising, lowering and laterally moving track structure can only be a maintenance nightmare.

Operationally, I don't see how this switch mechanism can operate faster than sliding a set of switch points about 3 inches one way or the other - with the need to raise, move and lower the switch rails into their desired position.

Never too old to have a happy childhood!

              

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Posted by Paul of Covington on Saturday, August 5, 2017 9:03 AM

Euclid

 

The stub points lift and drop back down as they shift positions.  Why do they need to lift up?  Why can’t they just shift laterally without lifting and falling?     

 

   My guess is that this is the way they lock into place, like tabs dropping into notches.   I don't know the details of the design, but it seems to me that it would be vulnerable to being fouled by loose ballast or other trash.

_____________ 

  "A stranger's just a friend you ain't met yet." --- Dave Gardner

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Posted by Euclid on Saturday, August 5, 2017 9:54 AM

Paul,

Yes, that would make sense and explain why the rails have to lift as they shift laterally.  It would be interesting to see the actual mechanical details of this switch rather that just the stylized animation.

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Posted by Semper Vaporo on Saturday, August 5, 2017 10:01 AM

Paul of Covington
 
Euclid 

The stub points lift and drop back down as they shift positions.  Why do they need to lift up?  Why can’t they just shift laterally without lifting and falling?  

My guess is that this is the way they lock into place, like tabs dropping into notches.   I don't know the details of the design, but it seems to me that it would be vulnerable to being fouled by loose ballast or other trash.

Well there ya go lettin' real world physics interfere with blue sky innovation and making a quick buck.

Semper Vaporo

Pkgs.

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