Use modern large-scale machinery to maintain the tracks, subgrade, bridges and tunnels of railway lines. In nature, it belongs to the five first-line industries of railway transportation (car service, responsible for shunting. Stations below the second class also belong to it. "Work" (maintenance and operation of locomotives) and electrical service (electrical service is responsible for installation and maintenance of catenary, track circuit and interlocking equipment) (vehicle maintenance) in locomotives.

It's a good industry!

Didn't I make myself clear? How to do it specifically is different for everyone!