How does a train stay on it's tracks when there is snow on them?

Question

In some places of the country it can snow 12" or more overnight. If tracks are completely covered in snow, how does a train operate on them without being derailed?

Answer 1

There are a few things in favor of a train staying on its tracks.  One is the sheer weight of the train pushing down giving it terrific traction.  I once saw a tanker truck full of fuel come around a sharp corner on one inch thick sheet of ice as if it was on dry asphalt and it was going at least 40-50mph!  It could do that just because of the sheer weight of it pushing down so many lbs per sq. inch.  The next thing is the plow on the front will adjust the depth of the snow its having to push through, clearing the tracks like a snowplow with a big V-blade on the front.  Also and most beneficial are the design of the wheels which have a ring molded around the inside of the wheels so that when it tends to drift left or right the right side ring will not allow the wheel to slide to the right, and the same effect on the left with the left wheel.  

Another thing trains have for traction is about a 1 1/2 inch tube just in front of each driving wheel the engineer can control to dump a bit of sand for the engine's wheels to get even more traction between the surfaces of the wheels and the rails!

Answer 2

It snows a lot more than that in some places.  Snow is relatively soft and easily shaped, unless it becomes packed ice.  Under normal conditions, a locomotive's weight presses the flanges through the snow, while the pilot or pilot-mounted snow plow pushes the snow out of the way.

Where the snow is deeper than a couple of feet, railroads use snow plows or snow blowers to clear a trench over the rails.  Where snow may be compacted hard enough to lift flanges off the rails, a "flanger" blade is used to tear the ice out, in a way similar to the operation of an old-fashioned can opener.

If you go out on YouTube and search for "train in snow," you will find all sorts of film about these processes.

Answer 3

Good question.

Snow can stall a train but, as pointed out above, "pilot plows" on the front of the locomotives will push considerable now out of the way, maybe up to tree feet or so, depending on various factors, such as tonnage and grade.  But, in mountainous territory, like the Donner Pass Route over the Sierras, snow removal is a constant battle.  The war is fought in four stages.

Already mentioned was the pilot plow, which we'll call stage 1.  The next piece of snow fighting equipment utilized is the "flanger."  This is towed behind the locomotive, and is equipped with two, separate plows underneath the flanger, so one throws to the left and the other throws to the right.  The blades are controlled by the engineer.  These plows actually extend below the top of the rail, keeping the flange ways clear.  Switches and crossings are marked with "flanger boards," looking like half of a "V" on top of a post, above the snow.  These tell the engineer when to raise the blades to clear the crossing or switches, invisible under the snow.

But, flangers can only keep up for so long.  Where the next problem lies is, the flangers leave behind them a "core," with snow piling up at the outside of the tracks.  The danger is that the core can get so deep that the uncoupling levers hit the snow and the train is unintentionally uncoupled while the train is moving.  Enter the "spreader."

This piece of equipment is pushed ahead of the engine.  As its name implies, it spreads the snow piled up by the flangers via two hydraulically powered "wings."  The Jordan spreaders with which I am familiar can cover an area thirty feet wide and push the snow over embankment or up against the hill.  Of course, if the storm(s) persist, then the spreaders run out of room to push the snow.

This is when the rotaries are placed into service.  SP's (now UP) wide wing rotaries were unique to the SP as was their cab forward articutaled locomotives.  The blade itself is perhaps 12 feet or so wide with steam powerred wings that can reach out and take an even bigger chunk out of the snow.

The blade is powered by four traction motors, the same as used under the locomotives for traction.  The difference, these are connected to the blade.  An old F-7 type covered wagon B unit provides the electricity.  There are steam generators aboard for de-icing the blade, positioning the wings and running the deflector, the latter allowing for the rotary to throw the snow to the left or to the right.  The sight of a 175 foot rooster-tail when one of these beasts is working hard is awesome.

The rotaries are usually placed at each end of a conventional locomotive consist allowing it to plow in either direction.  The engineer controls the equipment's moves, the Road Master usually is in charge of the wings, with another engineman running the blade.

The truth is, ice can derail equipment if allowed to accumulate between the rails.  In areas where the flanger cannot be used, such as over switches, grade crossings or inside some tunnels, the ice is removed by section men, either by hand or, in some tunnels and snow sheds, but using a good ol' shotgun.

Of course, there is the ever present threat of avalanche.  Where cores build and become unstable there is a pneumatically fired cannon that shoots charges into the offending cornices, explodes and creates a "controlled" avalanche, where waiting equipment removes the snow.

It has been a running gun battle between men, steel and snow for the last 145 years, and probably will be for the next 145 as well...

Answer 4

well... in MY part of the country it can snow 36" in one night...

the snow is nowhere near hard enough to stay on the track once hundreds of tons of train presses its wheels on it.

but you would FIRST use a snow plow or snow blower...

look up "white pass railroad" in Skagway, AK... they use a big red  12 foot snowblower. its freegin awesome

http://www.narrow-gauge.co.uk/gallery/sh...

Answer 5

Well, just the weight of the locomotives and rail cars, and a locomotive's front-mounted plow are usually enough, alone, to get a train through most typical snow storms and snow-covered tracks (unless ice or hard-packed snow forms over flange-ways [the open space for a locomotive's or rail car's wheels to pass over at a railroad or street crossing], which can cause a train to derail).

Snow does not usually become a problem for railroads until it gets several feet deep (for instance, snow drifts are usually the biggest problem where they can sometimes reach astronomical heights of 10-20+ feet, like in the Sierras and Cascades), when the blades mounted on the front of most diesel locomotives, cannot effectively remove the snow from the right-of-way.

If this is the case one might be lucky enough to see a railroad break out the ultimate snow removal machine, the rotary plow.  While rarely used today, they are an awesome sight to see in action.

Answer 6

The engines are so heavy that they actually mash the snow down as they pass over it. The inner side of the wheel has a rib or ridge that holds in from falling off the track.  The following cars ride through the ruts left by the engines.- Also, some trains have "SNOW PLOWS" attached to the front engine that clears the snow away.- Some snow IS SO deep that trains cannot travel through it until a special melter has been used.

                                                                  johna111

Answer 7

Just read all the answers; together, they completely explain how a train can stay on the tracks.  One more thing that helps; good ol' horse sense -- going a bit slower is safer.

Answer 8

It is not the snow on the tracks that is the problem. It is the temperature....when it gets really cold the rails can break and cause derailment.

Answer 9

That's what those pointed things on the front of trains are for. Removing snow/road kill/other foreign objects.

Answer 10

The wheels squish the snow off the tracks.  Steel wheels exert an enormous pressure on the tracks.  But that doesn't mean that snow can't be a problem; rail-mounted snowplows are used to remove it.

Answer 11

I cant add much except for some personal experiences.

Snow itself isnt likely to derail an engine but it is possible to get hopelessly stuck in a snowdrift and have to be rescued. Been there done that, more than once.

BUT, ice and compacted snow certainly can, especially over road crossings where automobile traffic packs the snow into the flangeways between the rail and crossing planks.

I remember one horrible day years ago (between ice ages) when we were derailed 5 times in one day, all but the last time we were able to back up and the wheels followed their original track in the ice and we fell back onto the rail.

Obviously the heavier the locomotive the less likely this is to happen.

This week in Montana Amtrak was temporarily suspended because of avalance danger near Glacier Park, freight trains still ran.

Railroad crews are easier to replace then paying customers apparently.