Tie exchanger

[1] The TKO is distinct from the track renewal train, a much more complex machine which replaces the entirety of the rails and ties at once.

While wooden railroad ties are treated with preservatives such as creosote to resist decay, they do not last forever and must be replaced every 20 to 40 years, depending on factors such as climate and the type of wood used.

The wooden railroad ties, weighing in excess of 100 pounds each, required a great deal of muscle to be moved.

[2] As an example, commuter railroad Metra maintains approximately 400 miles of track, and this translates to between 30,000 and 50,000 ties needing replacement per year.

[2] Faced with the need to replace tens or even hundreds of thousands of ties along their networks along hundreds or thousands of miles of tracks each year, in the 20th century railroads realized that they could save time and money (and broken backs of employees) by developing machines which could mechanize the process of tie replacement.

[5] Before a tie extractor/inserter can begin work, railroad workers must perform several tasks to prepare.

They will inspect the track where the machine will operate, marking damaged ties for removal using spray paint or some other form of identification.

A CSX tie exchanger in Waycross, Georgia, USA. The arm that grabs and moves ties can be seen at the center of the vehicle just above the rails. On either side of it are two of the clamps used to lift the rail. Two more clamps are in corresponding positions on the opposite side of the vehicle.
A close up view of the arm used to grab ties, along with two of the four rail clamps.