Management Significance and Parameter Selection of TBM Cutter

1. The purpose of TBM cutter management

Improve TBM cutter management, reasonably implement cutter maintenance, inspection and replacement, and establish an accurate and detailed TBM cutter ledger, so as to grasp and analyze the use of TBM cutting tools on time.

Therefore, a more reasonable component configuration for TBM disc cutter and a more appropriate maintenance process can minimize the cost input of TBM cutting tools, which is of great significance to reduce the use cost of cutting tools.

2. The management and implementation of TBM cutters

In actual construction, the inspection and replacement time of TBM cutters account for more than 20% of the tunneling construction time, and TBM cutters consumption is one of the most costly items in TBM construction. And the harder the rock, the longer inspection and replacement time, resulting in higher costs.

TBM cutter management not only determines the input of tunneling cost, but also improves the utilization rate of machines and ensures the duration of the project, which is of great significance to ensure smooth construction and reduce construction risks.

Mastering and skillfully using the methods of TBM cutter inspection and replacement and strengthening the monitoring of cutting tools can avoid large area damage caused by abnormal causes of TBM cutters, reduce the time of downtime due to cutter replacement, make effective use of cutters and effectively protect the cutter head, and improve the utilization efficiency of equipment.

3. Failure form and cause analysis of TBM disc cutter

Disc cutters are subjected to high working loads and shocks, as well as severe friction and high temperatures in rock breaking. The surface of each component (especially the cutter ring) is worn or degraded, so that the TBM disc cutters gradually lose their rock-breaking ability and fail.

At this time, the disc cutter needs to be replaced, and reasonable cutter replacement is beneficial to each tool to maximize its use value.

4. Reasonable parameter selection of TBM disc cutter

In the process of excavation, reasonable excavation parameters should be selected according to the geological conditions. TBM disc cutter has its specific load bearing capacity and starting torque. Exceeding its load bearing capacity will cause impact damage to the disc cutter and cause its failure.

When the friction force of the surrounding rock on the disc cutter is less than its starting torque, the disc cutter cannot be rotated and eccentric wear occurs. Therefore, when the joints of soft rock or the surrounding rock of the face are developed, it is necessary to adopt low speed and control torque to increase the starting torque, so as to avoid the partial grinding of the TBM disc cutter or the collapse of the surrounding rock of the tunnel face and damage the disc cutter.

When hard rock or face joints are not developed, it is necessary to use high speed and low penetration to avoid disc cutter damage due to excessive thrust.

When driving in the surrounding rock with uneven hardness and softness, it may also cause the disc cutters overloaded, so the advancing speed should be reduced as much as possible to protect the cutters and improve the bearing capacity of the spindle.

During the excavation process, the direction of the TBM should not be adjusted too fast. If the direction is adjusted too fast, it is easy to cause damage to the gauge cutter due to excessive force. Therefore, when adjusting the direction, it is necessary to slow down the excavation speed of the TBM cutter or stop advancing forward, and then adjust the excavation speed after the direction adjustment is completed.