Writer： admin Time：2021-06-19 08:26:46 Browse：371℃
Drum Cutters can be widely used in the excavation of tunnels, ditches, and municipal pipelines; highway pavement crushing, mining, rock and frozen soil excavation; open-pit coal mine excavation, surface regeneration, steel industry, forestry and other construction fields.1) Applied to tunnel excavation In most cases, the drum cutter is only used for the excavation of the tunnel outline, but in suitable strata such as medium and low hardness rock strata and permafrost layers, the drum cutter can be directly used for tunnel excavation. Excavation, especially in the process of breaking and excavating, has low disturbance to the ground and high safety. In the broken rock layer and old loess, the excavation volume can reach 30--60m3/h.
2) The drum cutter is especially suitable for areas where blasting construction is not suitable; the drum cutter is easy to operate, highly controllable, and the excavation contour is clear and accurate; it can easily solve under-excavation repairs in tunnels, internal surface grooving and side ditch excavation, etc. question.
3) Excavation: On-site excavation is generally carried out in two steps, that is, the two-step step method. Due to the need to store all the equipment on the steps, the upper and lower steps are 800 - 1100 m apart. Step-by-step excavation and support: After excavation, steel mesh, steel grid + spray-mixed support are used to support the tunnel. In soft rock, the footage depth of each excavation depends on the conditions of the face rock formation and the pre-design of the tunnel design unit, generally 50-80cm.
4) Excavation cycle: After using the drum cutter to excavate, the excavator withdraws from the tunnel face and stops at the side wall of the tunnel, and then the loader starts to excavate. After the excavation is completed, the support structure installation and spraying work are carried out immediately , and then carry out the excavation construction of the next cycle.
5) Solve the problem of excavation just after the support is completed: The excavation speed of the drum cutter in the clay (take the TD140 milling machine with a 30-ton excavator as an example) is about 30-60m3/h. When excavating with a milling excavator in the clay layer, it is rare that the cutter head is covered by clay and cannot be used. It can be solved by washing the cutter head with water or using a milling excavator to mill some dry and hard surrounding rock.