Roadheader is a small drilling machine used to drill underground tunnels and small diggers. The front of the machine is a multi-blade fork and the drill is drilled by turning it and the resulting soils are transported by the conveyor to the rear of the truck, which is usually located there.
In these devices, the drill bit is much smaller than the drilling depth, and the drilling of the section is completed with the movement of the head by an arm connected to the body.
The excavation of stone in tunneling by a machine is one of the two main methods of excavation of a tunnel. The first method is digging a part by a drill machine, which consists of an arm that is mounted on the cutting head and applied to the drill of the stone. On this header, the brushes or shear teeth are placed. The second method is to drill the entire tunnel TBM and TBM machines and cowhide or digger machines have been widely used.
The drill machines generally include a cutting arm mounted on a tensile chassis and in fact self-tensioning.
loading by the collecting arms of the rock drill in tunneling by a machine is one of the two main methods of excavation of the tunnel. First method The drill is part of the hub drill machine, which is an arm that is mounted on it and the stone drill is applied by it. The second method is to drill the whole tunnel through HF or TBM machines. TBMs and cowhide machines or rotary drill machines have been widely used.
Power and weight of operational flexibility The ability to drill a tunnel section with different shapes and its ability to maneuver to create intersections in mine tunnel paths is one of the main characteristics of the hammer drill machines. Lighter old vehicles (about 25 tons or less) in The drumming of medium-hard rocks has been unsuccessful. Because machine shaking caused damages to machine guns and often the machine itself. In a variety of heavy duty machine tools, the crank drill (90 tons up) all parts of the more advanced and robust structure And the power of the car has increased in proportion to it, and the maintenance costs of the service life are significantly reduced. It has been economically justified to dig harder rocks by these machines.
The Basis of Cutting Up the Drill Machine: A tambourine, Conical or abrasive
The most common form of head or crown in digging machines is the cones that rotate around a pivot along the axis of the car. The design of the conical shear crown and the position and direction for mounting it on the arm are in an optimal position Application of maximum shear force to the tunnel working front. For this reason, these type of blade digging machine have been able to meet the accepted operational requirements in difficult geological conditions and find a widespread use in Europe. In the cone method Compared to the drum, less time is spent on crushing or digging or penetrating on a toughened hard work front.
The cutting splitting mechanism or drum type widely accepted in continuous extraction machines for cutting relatively weak rocky faces such as coal fronts or various types of sedimentary rocks. In this system, a force of a compressive force or axial force through a threshing arm or head It pushes the tunnel to the front of the tunnel. Hammer drill machines are 20 to 30 percent lighter than conical drilling machines of the same capacity. Hard or solid rocky conditions require the shear force to concentrate, especially at the beginning of the tunnel working front, and the cone type cutting system In these cases, the system is more effective than the cutting machine type. The main features of the Cutter drum system type are :
The use of geysers or jets of water that operate at a pressure of over 700 times, according to reports, reduces the major cutting forces. And transported to a chain carrier. The movement of crushed material in the opposite direction of the tunnel’s chest and through the chain carrier is continuously pushed to the main system of shredding material.