What Does
Erector System Mean?
An erector system, in the context of tunnel boring machines (TBMs), is used for the placement of precast concrete tunnel segments. Once the cutting head has advanced to an appropriate distance, precast concrete liner segments are transported into the tunnel using mine service vehicles. The segments are then installed individually by the ring erector system. Upon successful installation of the liner segments, the machine’s hydraulic jack system pushes the cutting head forward, and the lining process is repeated.
Trenchlesspedia Explains Erector System
The erector system has both a fixed structure and a moving one. The fixed part has two longitudinal beams on which the sliding guides are mounted. The moving part consists of the rotating ring and pick-up system. The mechanical pick-up unit grasps the segment and retains it for the duration of the positioning operation.
The unit has three independent movements: swing = ±5%, pitch = ±5% and roll = ±5%. The erector system also has a coupling plate equipped with a bolt benching machine. The rotating structure of the erector is controlled by two planetary gears with sprocket drives and a crown wheel, and it is supported by rollers.