Rotary snowplow which is used for clearing train tracks after heavy snowfalls. The machine’s precursor was the wedge snowplow. The one seen above was built in 1899, retired in 1964 and later restored in 1995, getting occasional use on the White Pass and Yukon Route.
The plow is not self-propelled, so one or more locomotives are coupled behind it to push the plow along the line. An engine within the plow’s carbody rotates the large circular assembly at the front of the plow. The blades on this wheel cut through the snow and force it through a channel just behind the disk to an output chute above the blade assembly. [source]
Rotary snowplows are expensive due to their high maintenance costs, which the railroad incurs regardless of whether they are needed in a given year. As a result, most railroads have eliminated their rotaries, preferring to use a variety of types of fixed-blade plows that have significantly lower maintenance costs, in conjunction with bulldozers, which can be used year-round on maintenance-of-way projects. [source]
In 2001, the Rotary Snowplow was inducted into the North America Railway Hall of Fame. The hall of fame recognizes and establishes and enduring tribute to the people and things that have made significant contribution relating to railway industry in North America. The Rotary Snowplow was inducted in the “Technical Innovations” category with “National” significance. [source]