Exploring steel obstruction in front of TBM during excavation!
If there is an obstacle in front of the planning rote, the obstruction will be caught and detected from the TBM.
The electromagnetic waves are emitted from the transmitter coil equipped in the TBM to expose magnetism (primary magnetic field) to the steel obstruction.
The magnetic steel obstruction emits an induced current, and magnetism (secondary magnetic field) is formed. This magnetism (secondary magnetic field) is detected by the receiver coil equipped in the TBM to determine the presence or absence of steel obstruction.
Ground improvement around the obstruction from inside the TBM!
It takes time to cut obstruction. During that time, the ground around the obstruction will loosen, and ground improvement will be carried out to prevent the occurrence of subsidence of underground utilities and ground surface. The milling mall machine is devised so that chemicals can be injected from inside the TBM in case it is impossible to improve the ground from the ground level.
Cut steel obstruction into pieces and discharge!
The milling mole method consists of three devices which are TBM, special telescopic pipe, and special injection pipe. The TBM is equipped with a dedicated special bit dedicated to cutting obstruction, and has a built-in transmitter coil and receiver coil for obstacle exploration. The cutter bit also supports in-machine replacement. The special telescopic pipe is used when cutting the obstruction, and the TBM is pressed against the obstruction at ultra-low speed to cutting. The special injection pipe will be mounted equipment to improve the ground in front of the TBM and around obstruction.
Induce the TBM to a predetermined position in the shaft!
It is a system that induces the TBM to the position by installing a receiver coil at a predetermined position in the reception shaft. It measures from about 40m before reaching and calculates and displays the azimuth angle of the TBM in real time.