#地铁小百科 #
Have you ever seen the bottom of a tram?
Today, "Smurfs" will take you to see the rack machine of Line 7.
The full name of the driving machine is a fixed frame car machine, which is a large lifting and lifting equipment installed in an underground foundation pit.
It is used for overhaul operations such as train overhauls, frame repairs, fixed repairs and temporary repairs.
