PURPOSE: To facilitate the removal of a failed self-advancing trolley and the like by providing a parting rail section which can be freely extracted outside, at a specified position in a definite route, and concurrently providing transfer rails which can be freely connected to the extracted parting rail section.

CONSTITUTION: Rails 1 are parted at a specified position in a definite route 24 so that a parting rail section 1A is provided therein in such a way as to be freely extracted outside. Namely, a base frame 45 is provided from the lower section of a place where the rails are extracted, over the lower section outward to one side, two floor side rails 46 are then arranged in such a way as to be perpendicularly intersected with the definite route 24. And a movable stand 48 on the upper surface of which the parting rail section 1A is fixed, is so provided as to be freely movable over the floor side rails 46 so that it is thereby reciprocated by a drive device 50 via a chain 49. In the second place, relay rails 53 are arranged to the outside of the definite route 24, and an extracting trolley 60 capable of supporting a self-advancing trolley 20 on the upper section of which transfer rails 64 freely connectable to the relay rails 53 is provided, is provided at the opposite end section of the parting rail section 1A.