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Eastman346

Welded track?

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How does the MTA bring a long pieces of welded track through the tunnel system? I thought they weld inside the tunnels but that would cause too much fumes.

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How does the MTA bring a long pieces of welded track through the tunnel system? I thought they weld inside the tunnels but that would cause too much fumes.
Tracks are not welded together. And also, welding does not cause any fumes.

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Tracks are not welded together. And also, welding does not cause any fumes.

 

Are you sure? :confused:Then what do you call rails that are held together without a fishplate (aka rail joiner)? Ever rode the Staten Island Railway? 90% of the route is welded rail.

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Are you sure? :confused:Then what do you call rails that are held together without a fishplate (aka rail joiner)? Ever rode the Staten Island Railway? 90% of the route is welded rail.
I don't think Ive ever seen welded track in NYCT. SIR is a different story.

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Tracks are not welded together. And also, welding does not cause any fumes.

 

I used to watch the actual rail welding car layed up between the 8th Avenue and Fort Hamilton Parkway stations on the Sea Beach Line (N) in the early 90's. They were welding rails there for a whole summer sometime between years of 1991-1993. The welded rail would stretch out almost the whole distance from Ft. Hamilton Pkwy to 8th Avenue. It was very interesting operation to see.

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I used to watch the actual rail welding car layed up between the 8th Avenue and Fort Hamilton Parkway stations on the Sea Beach Line (N) in the early 90's. They were welding rails there for a whole summer sometime between years of 1991-1993. The welded rail would stretch out almost the whole distance from Ft. Hamilton Pkwy to 8th Avenue. It was very interesting operation to see.
I thought the tracks from what I always see are placed together and held down with ties and those giant bolts. I know on the elevated lines such as up by me, Rails are not welded, atleast I don't think so. On solid ground, now that I think of it, they are welded. I don't walk the structures and I'm no track worker.

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How does the MTA bring a long pieces of welded track through the tunnel system? I thought they weld inside the tunnels but that would cause too much fumes.

 

Fumes, dust, smoke.....just as long as customers do inhale it it's OK, they use industrial fans to blow away the smoke and dust away from stations.

 

Tracks are not welded together. And also, welding does not cause any fumes.

 

Tracks can and are welded together, not all lines but I know for sure on the Sea Beach line.

Welded rails are much more quieter than rails with joints.

They once tried it on a structure but it was a disaster once the summer came along....

 

It's called CWR.

 

I used to watch the actual rail welding car layed up between the 8th Avenue and Fort Hamilton Parkway stations on the Sea Beach Line (N) in the early 90's. They were welding rails there for a whole summer sometime between years of 1991-1993. The welded rail would stretch out almost the whole distance from Ft. Hamilton Pkwy to 8th Avenue. It was very interesting operation to see.

I was there this past summer and we laid rails there, they were all to be welded.

Unfortunately I wasn't there to witness my first welding.

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http://en.wikipedia.org/wiki/Rail_tracks

 

Continuous welded rail

 

Welded rail jointMost modern railways use continuous welded rail (CWR); in this form of track, the rails are welded together by utilising the thermite reaction or flash butt welding to form one continuous rail that may be several kilometres long. Because there are few joints, this form of track is very strong, gives a smooth ride, and needs less maintenance. Welded track has become common on main lines since the 1950s.

 

Because of the increased strength of welded track, trains can travel on it at higher speeds and with less friction. Welded rails are more expensive to lay than jointed tracks, but have much lower maintenance costs.

 

Rails expand in hot weather and shrink in cold weather. Because welded track has very few expansion joints, if no special measures are taken it could become distorted in hot weather and cause a derailment (a condition known in America as sun kink, referred in Britain as buckling).

 

To avoid this, welded rails are very often laid on concrete or steel sleepers, which are so heavy they hold the rails firmly in place. After new segments of rail are laid, or defective rails replaced (welded in), the rails are artificially stressed. Great attention is paid to compacting the ballast effectively, particularly the shoulder over the ends of the sleepers, to prevent them from moving. Even so, in extreme weather, foot patrols monitor sections of track known to be problematic.

 

The stressing process involves either heating the rails causing them to expand,[1] or stretching the rails with hydraulic equipment. They are then fastened (clipped) to the sleepers in their expanded form. This process ensures that the rail will not expand much further in subsequent hot weather. In cold weather the rails try to contract, but because they are firmly fastened, cannot do so. In effect, stressed rails are a bit like a piece of stretched elastic firmly fastened down.

 

Engineers try to heat the rail to a temperature roughly midway between the average extremes of hot and cold (this is known as the 'rail neutral temperature'). If temperatures reach outside normal ranges however, welded rail can buckle in a hotter than usual summer or can actually break in a colder than anticipated winter.

 

Joints are used in continuously welded rail when necessary; instead of a joint that passes straight across the rail, producing a loud noise and shock when the wheels pass over it, two sections of rail are sometimes cut at a steep angle and put together with a gap between them - a breather switch (referred to in Britain as an expansion joint). This gives a much smoother transition yet still provides some expansion room.

We used concrete "ties"

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How does the MTA bring a long pieces of welded track through the tunnel system? I thought they weld inside the tunnels but that would cause too much fumes.

 

During the welding of the Sea Beach tracks, the tracks were placed in a train that had the fronts cut out to allow the welded rails to be placed inside and run through several cars.

 

I don't think these trains would maneuver through turns, as a matter of fact they didn't need to because the Sea Beach is mostly straight line except for a few portions of the line. As for welded rails in the tunnels, Trackworker pretty much summed it up.

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Most of the Brighton Line is welded as well. After the crossovers, south of Prospect Park, Its welded all the way to Neptune Av, then elevated to Stillwell.

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During the welding of the Sea Beach tracks, the tracks were placed in a train that had the fronts cut out to allow the welded rails to be placed inside and run through several cars.

 

I don't think these trains would maneuver through turns, as a matter of fact they didn't need to because the Sea Beach is mostly straight line except for a few portions of the line. As for welded rails in the tunnels, Trackworker pretty much summed it up.

 

Yeah, we just pretty much laid the panels down and butted the rails together if they had space in between them.

 

I should have taken pics.

 

They need CWR on the line, you have houses right on top of the tracks ....almost.

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thanks for all the responses guys.

 

During the welding of the Sea Beach tracks, the tracks were placed in a train that had the fronts cut out to allow the welded rails to be placed inside and run through several cars.

 

now if only there was a pic to show this in action.

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