Original title: Structure of down-the-hole drill | Working principle and classification of down-the-hole drill Let the mood travel Down-the-hole drill, which you may not hear much about, is a kind of drilling machine, which is often used for drilling rock anchor cable holes, anchor holes, blasting holes, grouting holes and other drilling construction in urban construction, railway, highway, river, hydropower and other projects. In this article, the small drill will give you a detailed introduction to the structure, working principle and classification of the down-the-hole drill, all to understand it! Mechanism Composition of Large Open-pit Down-the-hole Drill 1. Drilling frame: The drilling frame is the guide rail for the sliding of the slewing device and the propulsion and lifting of the drilling tool. 2. Carriage: The carriage is a square box structure welded by steel plates, which is used to connect and support the drilling frame. 3. Slewing device: The mechanism is composed of hydraulic motor, spindle mechanism, pressing head, sliding plate and central air supply mechanism. A chain of the propelling mechanism is fixed on the sliding plate through a pin shaft and a spring damping mechanism. 4. Propulsion mechanism: The propulsion mechanism is composed of propulsion hydraulic motor,dth button bits, chain wheel group, chain and buffer spring. 5. Rod unloader: The rod unloader is composed of the upper rod unloader body, the lower rod unloader body, the rod clamping oil cylinder and the rod unloading oil cylinder. 6. Dust removal device: The dust removal device is divided into dry dust removal, wet dust removal, mixed dust removal and foam dust removal. 7. Traveling mechanism: The traveling mechanism is composed of traveling frame, hydraulic motor,overburden drilling systems, multi-stage planetary reducer, crawler, driving wheel, driven wheel and tensioning device. 8. Frame: air compressor unit, dust removal device, oil tank pump unit, valve unit and cab are all installed on the frame. 9. Body slewing mechanism: The mechanism is composed of slewing motor, brake, reduction gear, pinion, slewing bearing, etc. 10. Drill frame deflection mechanism: This mechanism is composed of deflection cylinder, hinge shaft and hinge seat, mining dth bit ,rock drilling tools, which can make the drill frame deflect left and right and adjust the drilling angle. 11. Compressed air system and impactor: The compressed air system is generally equipped with a screw air compressor, which provides compressed air for the high wind pressure impactor and the blowing and ash removal system of the laminar flow dust remover. Basic composition of universal down-the-hole drill Expand the full text The drilling tool is composed of drill pipe, button bit and impactor. When drilling, two drill rods are used to connect the rod to drill, and the stainless steel plate is used. The rotary air supply mechanism consists of a rotary motor, a rotary speed reducer and an air supply gyrator. The rotary reducer is a three-stage cylindrical gear enclosed anisotropic component, which is automatically lubricated by a spiral oiler. The air supply gyrator is composed of a connecting body, a sealing element, a hollow main shaft, a drill rod joint and the like, and is provided with a pneumatic clamping claw for connecting and disconnecting the drill rod. The lifting pressure regulating mechanism is to lift the slewing mechanism and drilling tool by the lifting motor with the help of the lifting reducer and lifting chain. The closed chain system is provided with a pressure regulating cylinder, a movable pulley block and a waterproof agent. During normal operation, the piston rod of the pressure regulating cylinder pushes the movable pulley block to realize decompression drilling of the drilling tool. Working principle of down-the-hole drill The working principle of the down-the-hole drill is the same as that of the ordinary percussive rotary pneumatic rock drill. The pneumatic rock drill combines the percussive rotary mechanism, and the impact energy is transmitted to the drill bit through the drill rod; while the down-the-hole drill separates the percussive mechanism (impactor) and dips into the bottom of the hole. No matter how deep the hole is drilled, the drill bit is directly installed on the impactor, and the impact energy is not transmitted through the drill rod, thus reducing the loss of impact energy. With the increase of drilling depth, the loss of rock drilling capacity at the submerged rod and joint (medium-deep hole drilling) increases, the drilling speed decreases significantly, and the cost increases. In order to reduce the loss of capacity and improve the drilling efficiency, a down-the-hole drill was designed in the actual project. The down-the-hole drill is also powered by compressed air, and the rock is broken by rotary impact to form holes. Its working principle is that the pneumatic impactor of the down-the-hole drill together with the drill bit is installed at the front end of the drill rod. When drilling, the propulsion mechanism makes the drilling tool continuously propel and applies a certain axial pressure to the bottom of the hole, so that the drill bit contacts with the rock at the bottom of the hole; The rotary mechanism makes the drilling tool rotate continuously, and the impactor installed in front of the drill pipe makes the piston impact the drill bit back and forth under the action of compressed air to complete the impact on the rock. The compressed air enters from the rotary air supply mechanism, reaches the bottom of the hole through the hollow rod, and discharges the broken rock powder from the annular space between the drill pipe and the hole wall to the outside of the hole. It can be seen that the essence of down-the-hole drilling is the combination of two rock crushing methods of impact and rotation under the action of axial pressure, in which the impact is intermittent and the rotation is continuous, and the rock is continuously crushed and sheared under the action of impact and shear force. Percussion work plays a leading role in DHD. Classification of down-the-hole drill The structure of down-the-hole drill has two types: integral type and split type. According to the exhaust mode, it can be divided into side exhaust and center exhaust. According to the shape of the hard alloy embedded in the working surface of the down-the-hole drill, it can be divided into blade-type down-the-hole drill, column-tooth down-the- hole drill and blade-to-hole mixed down-the-hole rig. The integral down-the-hole drill is a single down-the-hole drill whose head and tail are made into one. It is easy to process and use, and can reduce the loss of energy transmission. The disadvantage is that when the working face of the down-the-hole drill is damaged, the whole is scrapped. The head of the split down-the-hole drill is separated from the tail (shank) of the down-the-hole drill, and the two are connected by special threads. When the head of the down-the-hole drill is damaged, the drill shank can still be used, thus saving steel. However, the structure is more complex, and the energy transfer efficiency is reduced. Article content source network, if there is infringement, please inform! END Source: Drilling Rig Business Circle We are committed to protecting the copyright of the author, the source of the content has been marked,fastest dth hammer, only for the dissemination and sharing of knowledge. No other commercial profit, if there is infringement, please contact us to delete. Push Return to Sohu to see more Responsible Editor:. wt-dthtools.com