Motorcars, Speeders and Railcars

By Wayne Parsons

Switch Inspection on the CNRR

Track inspection has many elements and switches are a major priority.  While waiting for a train, CN Foreman Bruce Easton walked us through the finer points of a switch inspection. 


Although this is CWR there are many bolted joints around switches.  Bruce says that these plates will break first on one side of the rail and then the other, but not both at once.  If you find both plates broken, your inspection has been delayed too long or a previous inspection missed something.

Bruce checks the gauge on the curve leading from the switch into the long siding.  This is a common area to find the rail spread.  Gauge is 56 1/2 inches with a maximum tolerance to 57 1/2 inches.  The wider the rails are apart the more effort it takes to move the train.

 

This is an insulated joint that uses pieces of tough plastic to electrically separate the two adjacent rails.  CN procedures require the inspector to paint insulated joints blue.  The idea is to help operating crews identify them, and if you were close enough to paint it blue then you were close enough to properly inspect it.

These wires help assure good electrical contact between all the rail and switch elements.

Depending on the switch position, the train stays left on the main line or goes into the siding on the right.  For either event the wheels pass over a "X" in the rail called a frog.  When staying on the main line, the guard rail (left end of the tape measure) must be adjusted to guide the wheel flanges to the left of the point within the frog. 

The point itself often wears down and must be repaired using a welder to add new metal that is then ground into final shape and tolerance. 

Due to the stress on all switch elements, large screw bolts replace spikes which wiggle loose.  Bruce easily pulls this bolt from the tie demonstrating that it too has come loose over time.  A repair that will last five years is made by pouring a special epoxy into the hole and screwing the bolt back into the tie.

The metal building on the left houses switch control and signal relays.  Bruce is discussing the need for good ballast and drainage around switches to prevent water puddles.  A water puddle could become a block of ice freezing the switch solid thus making it inoperable.

In winter the heater shed in the background blows hot air into the switch points and through the ducts Bruce is standing on keeping all the moving cross bars free of snow.

Careful adjustment of the cross bars and good alignment extends the life of the switch points.  Note the bar (underfoot) on the outside of the rail used to keep the ties properly spaced.

The switch heater uses the propane tank right.  Thank you Bruce Easton for the lesson!

Answer: the frog

POP QUIZ - What switch part / assembly is missing from this photo?  Hint: the guards for the missing part are still in place.

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