Tunnel Cantenary

I don't have any resources, but it seems to me that there would be a pole outside each side of the tunnel, and inside the tunnel the cantenary would be suspended by small stand-offs in the ceiling of the tunnel.

For reliability you will want to make sure that inside the tunnel there are no splices to the wire. As long as the wire is held solidly, and works well before the tunnel is built, it should not have any problems after tunnel construction. You might want to think about making the tunnel removable, or accessible just in case. The one place you can't reach, is the one place Murphy will play with.

I was maybe thinking of a piece of flexible metal in the tunnel

I was considering maybe mounting a piece of code 148 rail on the "roof" of the tunnel (the portion not seen past the tunnel portal entrance) which would provide constant continuity....the trick would be how to keep it clean!

But the wire around the tunnel portal is what I have a particular interest in finding out how the prototype handled it!

Having GOOD access to whatever is done is a must just in case Mr. Murphy wants to pay a visit!  But hopefully it will not be needed that often.

Ken L.

 

Trolley Wire in Tunnel and Buildings

In most cases the live overhead was surrounded on three sides by an insulated trough.  What has been done in the past was to use a metal channel as the overhead in the tunnel or building with the overhead wire carried about half an inch into the center of the channel and soldered to the channel.  That way the metal channel contains the trolley pole so it will not "dewire" inside the enclosed area and the wire soldered in the center of the channel will cause the trolley pole to guide on to the overhead wire when exiting the tunnel or building.

A couple of the trolleys don't use single pole...

.. instead they use a pantograph so i don't think the "channel" would work, or would it?

Thanks.

Ken L

Veissmann makes a "tunnel"

Veissmann makes a "tunnel" overhead system that uses a flexible metal strip for inside the tunnel that you attach the overhead wire to. It is designed more for pantographs so don't know if it will work for trolley poles.

As for the tunnel entrances, if you are using catenary, most prototypes attach the messenger wire (the top one) to an anchor on the tunnel portal while the contact wire continues into the tunnel. 

If you use google to search for images of streetcar tunnels you can get several photos showing the entrances and how the wires are set up by the prototype.

Phillie

Here is a picture of a modern trolley (LRV) coming out of a tunnel (the Subway-Surface Lines from downtown Phillie to West Phillie).  The tunnel entrance is on the right hand side, what looks like a "garage door".

Pacific Electric

Here's a couple I found of some old PE tunnels:

http://www.minervaclassics.com/railroad/LAArkv02.jpg

http://www.pacificelectric.org/wp-content/uploads/2009/12/MP-00488.jpg

Cheers!
Marc

Tunnel Cantenary

Use a brass channel to guide poles in tunnel, crimp ends to guide pole back on to the wire.   Pantagraphs  will slide along bottom picking up power,

There is a long trolley tunnel in Scranton Penn. in use every day.

patrick

Traction Line going into a tunnel?

If you are looking for a picture, here is one from the Pacific Electric Railway Historical Society that shows the interior of the entrance to the Subway Tunnel just north of downtown LA on the Hollywood and San Fernando Valley routes of the Western District:

http://www.pacificelectric.org/wp-content/uploads/2009/12/MP-00489.jpg

Bob Kelly

WRMRC Sudbury Division http://www.wrmrc.ca