1883results about "Drill bits" patented technology

In one aspect of the present invention, a drill string has a drill bit with a body intermediate a shank and a working face. The working face has a plurality of blades converging at a center of the working surface and diverging towards a gauge of the working face. At least one blade has a cutting element with a carbide substrate bonded to a diamond working end with a pointed geometry. The diamond working end also has a central axis which intersects an apex of the pointed geometry. The axis is oriented between a 25 and 85 degree positive rake angle.

The disclosure describes an expanding drill device for expanding a pilot bore by moving the expanding drill device along a specified drilling line comprising: a housing; a drill head that has a cutting wheel which is arranged on the drill side of the expanding drill device so as to be rotatably mounted and driven about a rotational axis and relative to the housing and on which at least one drill tool for loosening the ground or the rock is arranged; and a drill-side connection for producing a connection to a pipe section located in the pilot bore on the drill side, wherein the drill side centrally has at least one receiving chamber for the loosened ground or the loosened rock, said receiving chamber being connected to a material conveyor device of the expanding drill device.

The invention belongs to the field of drilling, and particularly relates to a large-diameter cluster type pneumatic down-the-hole hammer raise-boring reamer bit and a drilling method.The bit comprises a center pipe, a cluster body, an air chamber, a down-the-hole hammer, a synchronous check valve, an air chamber pressure balance control assembly and a concave slag falling channel and is used for transmitting torque and rotating speed and conveying high-pressure air; the top of the central pipe is sleeved with a flange used for being connected with a drill rod, the central pipe is sequentially sleeved with a front guide wing plate, an upper fixing plate, a middle plate, a high-frequency rear seat, an air chamber peripheral cylinder and an air chamber lower cover plate in the extending direction of the central pipe, and the front guide wing plate, the upper fixing plate, the middle plate, the high-frequency rear seat, the air chamber lower cover plate and the central pipe jointly form a cluster body; two ends of the air chamber peripheral cylinder are respectively connected with the high-frequency rear seat and the air chamber lower cover plate to form an air chamber; according to the drill bit, the multiple down-the-hole hammers are integrated through the cluster body, efficient rock breaking and continuous slag discharging are achieved in combination with air chamber energy gathering, synchronous check valve control and a concave slag falling channel, and the drilling efficiency is improved by more than 10 times.

The invention relates to the technical field of power tower pile foundation construction equipment, and discloses a power tower foundation pile drilling equipment and a soil discharge method thereof, comprising a base, a gantry, several power heads, a drill rod and a drill bit; several mobile power sources are arranged on the base; a horizontal beam of the gantry is slidably installed between two vertical beams, and the vertical beams of the gantry are slidably installed on the base, and power output ends of the several mobile power sources respectively push the ends of the two vertical beams, and the sliding directions of the vertical beams are perpendicular to the length directions of the vertical beams and the vertical beams move closer to or away from the base when sliding; the drill rod is installed on the bottom end face of the horizontal beam, and the axis of the drill rod is parallel to the length direction of the vertical beam, and the drill rod is driven to rotate by the power output ends of the several power heads; the drill bit is fixedly installed at the bottom end of the drill rod, so that the drill bit can slide back to a position away from the drill hole and the base when completing slag cleaning, thereby solving the problem in the prior art that soil slag and rock chips easily fall into the pile hole or the equipment base when the drill bit cleans slag, thereby reducing the working efficiency of the drill bit.

The invention relates to the technical field of mixing pile machines, in particular to a two-way mixing drill bit structure for a mixing pile machine and a construction method.The two-way mixing drill bit structure comprises a sleeve body, and multiple sets of sleeve holes are formed in the outer wall of the sleeve body; a rotary shaking mechanism is arranged in the sleeve body, and an air injection blowing mechanism and a bidirectional rotating mechanism are arranged on the sleeve body; the rotary shaking mechanism comprises sliding grooves formed in the inner wall of the sleeve body and corresponding to the two sides of the sleeve hole, the inner wall of each sliding groove is slidably connected with a lifting plate, a spring is fixedly connected to the position, corresponding to the interior of the corresponding sliding groove, of one end of the outer side of each lifting plate, and each spring is fixedly connected with the corresponding sliding groove. According to the device, a lifting plate can move inwards and outwards, so that a pushing column is driven to do the same movement, soil in a sleeve hole is pushed away, the sleeve hole is prevented from being blocked by the soil, and the flowability of the sleeve hole is guaranteed.

The invention relates to the technical field of drilling engineering, and discloses an impact-assisted rock breaking inwards-concave PDC drill bit which comprises a drill bit body and an impact structure, and the drill bit body is provided with an inner cavity and a first transmission protrusion arranged at the head of the drill bit body; the impact structure comprises a turbine, a transmission shaft and an impact blade, the turbine is arranged in the inner cavity of the drill bit body, the impact blade is arranged outside the drill bit body, the transmission shaft is connected between the impact blade and the turbine and provided with a second transmission protrusion, and the turbine is used for driving the transmission shaft to rotate; the second transmission protrusion and the first transmission protrusion abut against each other or are staggered in the rotating process. The impact cutter wings are used for stretching out relative to the drill bit body when the second transmission protrusions abut against the first transmission protrusions; a reset spring is further arranged between the transmission shaft and the drill bit body and used for driving the impact blades to reset when the second transmission protrusions and the first transmission protrusions are staggered. The high-frequency axial reciprocating motion of the impact blades directly crushes the center area of the drill bit, and the rock breaking efficiency of the center area of the drill bit is improved.

A rapid assembly and automatic sampling drilling tool for frozen soil layer exploration includes a fixed flow divider, a flow guide pipe, a coring pipe and a drill bit. The fixed flow divider is connected to the drill bit through the flow guide pipe and the coring pipe mounted between the fixed flow divider and the drill bit. Two ends of the flow guide pipe communicate with the fixed flow divider and a main flow channel in the drill bit respectively. Hot water in the fixed flow divider can be conveyed into the drill bit through the flow guide pipe and sprayed from a nozzle arranged on the drill bit for drilling and coring operations. An inlet of the coring pipe communicates with a coring channel in an inner cavity in the drill bit, and a core sample drilled by the drill bit is taken out through the coring pipe.

The utility model relates to the field of drilling tools for wells, in particular to a self-adaptive rotary steering drilling tool which comprises a drill bit body and a damping column, a plurality of blades are sequentially arranged on the crown portion of the drill bit body in the circumferential direction, the cutting faces of the blades are fixedly connected with a plurality of cutting teeth, and mounting holes are formed in the outer side faces of the blades. Steel sleeves are fixedly arranged in the mounting holes, the damping columns are movably inserted in the steel sleeves, the ends, located in the steel sleeves, of the damping columns are fixedly connected with connecting bases, adjusting plates are arranged between the connecting bases and the bottoms of the steel sleeves, and outer-layer low-rigidity spiral springs are connected between the adjusting plates and the connecting bases. An inner layer high-rigidity conical spring is arranged on the inner side of the outer layer low-rigidity spiral spring, and an adjusting assembly for adjusting the adjusting plate and the bottom of the steel sleeve is arranged on the steel sleeve. The drill bit can better adapt to different pressure requirements, and the drill bit is prevented from bearing overlarge impact force, so that the cutting teeth are protected, and the service life of the drill bit is prolonged.

The utility model discloses a geological drilling coring device which comprises a frame body, a placing table is installed on the upper portion of the frame body in a sliding mode, a motor is connected to the upper portion of the placing table through bolts, the motor is connected with a transmission shaft through a belt, a coring barrel is fixedly connected to the bottom of the transmission shaft, and a drill bit is fixedly connected to the bottom of the coring barrel. A cutting-off structure is arranged in the coring barrel and comprises a cavity and a first gear, a sliding block is slidably installed in the cavity, a rack is fixedly installed on the upper portion of the sliding block, a second gear is rotatably installed in the cavity, the second gear is connected with the rack in a meshed mode, and a double-face gear ring is rotatably installed at the upper position in the cavity. The double-face gear ring is connected with the second gear in a meshed mode, the double-face gear ring is connected with the first gear in a meshed mode, and a rotating shaft is fixedly installed at the top of the first gear. According to the geological drilling coring device disclosed by the utility model, a required core sample can be completely stored in the device.

A milling bit is disclosed for debris collection within a wellbore. A check valve can be part of a debris removal tool that includes a motor, a pump, a gearbox, a bailer, the milling bit, and rotational shafts. In an example, on its uphole end, the milling bit can be coupled with the check valve. On its downhole end, the milling bit can be configured for debris removal with cutting edges. The downhole end can also include openings that provide access to an internal cavity of the milling bit. The internal cavity can extend the entire length of the milling bit. This allows the pump to pull drilling fluid into the bailers through the milling bit and check valve. As a result, the debris removal tool can simultaneously remove obstructions in a wellbore and collect debris from the obstruction removal.

The invention relates to a mortar anchor rod construction device and a mortar anchor rod construction method. The construction device comprises a drill rod, an impactor and a drill bit which are sequentially connected, and is further provided with a wall protection sleeve, the rear end of the drill rod is connected with an output shaft of the rotary driving device, the wall protection sleeve is arranged on the outer side of the drill rod in a sleeving mode, a rotary fit clearance is reserved between the wall protection sleeve and the drill rod, the rear end of the wall protection sleeve is connected with an output shaft flange of the rotary driving device, and an annular drill bit structure is arranged at the front end of the wall protection sleeve. The construction device is used for drilling an anchor rod hole, after drilling is completed, the protection casing pipe is disconnected from the driving shaft of the rotary driving device, the mortar anchor rod construction device is returned, and the protection casing pipe is reserved in the anchor rod hole in situ. The device is suitable for occasions where surface layer covering soil is thick or loose, hole collapse can be effectively avoided, and the working efficiency can be improved.

Disclosed herein is a hand-held power tool including a motor housing, a motor in the motor housing, an auger coupled to the motor and having a rotational axis, and a first handle coupled to the motor housing and including a grip. In some embodiments, the rotational axis of the auger and an axis of the grip subtend to an acute angle.

The utility model discloses a rotary excavating reamer for a cast-in-place pile, and particularly relates to the technical field of engineering reaming equipment. The rotary excavating reamer for the cast-in-place pile comprises a connecting shaft, a driving box is arranged at the bottom end of the connecting shaft, a base is fixedly connected to the bottom of the driving box, a conical drill bit used for rotary excavating of the cast-in-place pile is fixedly connected to the bottom of the base, a plurality of rotating discs are rotationally connected to the base, and a positioning block is fixedly connected to each rotating disc. A tool apron is movably connected to the positioning block, and a reaming tool is fixedly connected to the tool apron. And a plurality of transmission connecting pieces are arranged in the driving box, the transmission connecting pieces are movably connected with the positioning blocks, and a driving mechanism is arranged in the driving box and used for driving the transmission connecting pieces to rotate so as to drive the reaming cutter to achieve angle adjustment. The utility model solves the problems that the linkage property of the reamer is insufficient in the process of adjusting the hole diameter of a reaming hole, and the assembly efficiency of the reaming piece is low in the disassembly and assembly process.

A method and a device for machining an elongated workpiece having a shaft extending in the direction of the workpiece longitudinal axis forms at least one groove with a defined groove surface on the workpiece by material removal by a laser beam directed with its beam axis onto the workpiece surface and guided along a laser path extending exclusively parallel to a groove profile curve corresponding to the intersection between the groove surface to be produced and a geometric plane that forms an angle β with the workpiece longitudinal axis, where 90°≥β≥the angle of groove inclination. The distance between the curve and the path is predetermined such that the workpiece material located in the geometric plane on the path side facing away from the curve completely sublimates or vaporizes due to the laser beam power density when the beam is guided along the path.

A method including receiving a three-dimensional scan of a coating that coats an object. The coating and the object, in combination, have a shape. The method also includes flattening the three-dimensional scan to generate flattened data. Flattening includes conforming scan data in the three-dimensional scan to zone data for zones of a layout. The zones represents sections of the shape cut along boundaries in the shape. Each of the zones represents a corresponding thickness of the coating in a corresponding section of the sections. The method also includes vectorizing the flattened data into a vector data structure. The method also includes generating a prediction whether one or more zones of the zones are out of an engineering tolerance for the coating. Generating the prediction is performed by a machine learning model that takes, as input, the vector data structure and produces, as output, the prediction.

The invention discloses a construction method for salt cavern slim hole drilling cavity detection and injection and production well transformation. The construction method mainly comprises the six steps of cavity detection operation, packing operation, conduit operation, first-time reaming and well cementation, second-time reaming and well cementation and third-time open hole cavity penetrating operation. Compared with the prior art, the construction method for detecting the salt cavern slim-hole drilling cavity and transforming the injection and production well has the advantages that the drilling cost input is reduced, the working period is shortened, meanwhile, deflection and borehole wall instability are effectively avoided, and the construction safety is improved.

Provided is a whipstock and well system. The whipstock, in one aspect, includes a coupling section having a first radius of curvature, the coupling section configured to engage with a mill bit when running in hole. The whipstock, in accordance with this aspect, further includes a casing breakthrough section having a second radius of curvature, and a controlled exit section having a third radius of curvature, wherein the second radius of curvature is less than the third radius of curvature.

The utility model relates to a raking pile rock-socketed percussion drill hole-forming barrel drill bit, which belongs to the technical field of barrel drill bits, and comprises a rock percussion drill hole-forming barrel drill bit body, a rotary drilling machine, a connecting shaft, a flange plate and a bolt, and a reinforcing mechanism is arranged at the top of the rock percussion drill hole-forming barrel drill bit body. The reinforcing mechanism comprises a reinforcing sleeve fixedly installed on the peripheral wall of the connecting shaft. According to the raking pile rock-socketed percussion drill hole-forming barrel drill bit, the overall compressive strength of a connecting shaft is enhanced through the effect of a reinforcing sleeve, a connecting plate is fixed through the effect of an arc-shaped mounting base and a screw, and meanwhile an arc-shaped supporting plate is mounted in the reinforcing sleeve; part of pressure is shared to the rotary drilling machine under the action of the arc-shaped supporting plate, the supporting rod and the connecting plate, the influence of gravity and pressure on the connecting shaft when the drill bit body of the rock impact drill hole-forming barrel drill inclines is reduced, and therefore the service life of the connecting shaft is prolonged, and the stability of the connecting shaft is improved.

The invention belongs to the technical field of PDC drill bits, and particularly relates to a rotatable blade PDC drill bit which comprises a drill bit body. A plurality of supports are fixedly connected to the drill bit body, three inserting grooves are formed in each support, and the three inserting grooves are one long inserting groove and two short inserting grooves. A blade wing is arranged on the support; three fasteners of the same type penetrate through one first inserting block and two second inserting blocks respectively to be connected to the support in a threaded mode, so that the blades are assembled, large torque and impact force can be borne in the drilling process, the blades are not prone to loosening, the multiple blades are installed on the drill bit body in the drilling process, and the drilling efficiency is improved. The multiple blades rotate along with the output end of the drilling machine to drill into a soil rock layer, and rotation of the PDC drill bit blades is achieved. When a certain blade is abraded and damaged, the blade can be conveniently taken down from the support to be replaced only by disassembling the corresponding fastener, the whole drill bit does not need to be disassembled on a large scale, the maintenance cost is greatly reduced, and the maintenance time is greatly shortened.

The invention discloses an autonomous rock-soil body drilling instrument based on the bionic principle and a drilling method thereof.The autonomous rock-soil body drilling instrument comprises a drill bit, a propelling steering mechanism, an anchoring mechanism, an electric control integrated module and a ground control unit, and the drill bit, the propelling steering mechanism and the electric control integrated module are sequentially connected; anchoring mechanisms are arranged between the drill bit and the propelling steering mechanism and between the propelling steering mechanism and the electric control integrated module; the drill bit is used for cutting a rock-soil body and backwards conveying and discharging the cut rock-soil body to the outside of the drill bit; the propulsion steering mechanism is used for driving the drilling instrument to linearly advance and steer; the anchoring mechanism is used for providing counterforce required by drilling or resetting for the drilling instrument through meshing and separation with surrounding rock and soil bodies; and the electric control integrated module is connected with the ground control unit through an integrated communication cable. The device simulates an anchoring-propelling mechanism of natural organisms, realizes autonomous drilling without an external counter-force device, a slurry protection wall and a probe rod, and has the capabilities of multi-directional drilling, active obstacle avoidance and real-time acquisition of a continuous geological section.

The invention provides a tool applied to the field of petroleum drilling, and particularly relates to an electric control intelligent coring drill bit which comprises a power module and a cutting module, a limiting switch is arranged in the cutting module, the drill bit normally drills, a rock core passes through the interior of the drill bit and enters a coring barrel, and when the top of the rock core in the coring barrel triggers the limiting switch, the limiting switch is switched on. The MCU receives a coring completion signal, the electromagnetic valve is controlled to be opened through the MCU, high-pressure drilling fluid enters a turbine cavity through a mandrel hole, under the action of the high-pressure drilling fluid, the turbine rotates to generate motion and power, the motion and the power are transmitted to the rotating ring through the rotating disc and the rotating sleeve, the rotating ring rotates to push the connecting rod, the connecting rod pushes the evenly-distributed cutting knives, and therefore coring is completed. And the uniformly distributed cutting knives and the coring cylinder form a sealing cavity, the cut rock core is placed in the sealing cavity, and the cut rock core is taken out after pulling out of the drill. The intelligent degree of the drilling coring bit can be effectively improved, and the drilling coring efficiency and success rate are effectively improved.

A fixed cutter drill bit for drilling an earthen formation has a central axis and a cutting direction of rotation about the central axis. The drill bit includes a bit body configured to rotate about the central axis in the cutting direction of rotation. The bit body includes a bit face and a blade extending radially along the bit face. The blade has a leading side relative to the cutting direction of rotation, a trailing side relative to the cutting direction of rotation, and a cutter-supporting surface extending from the leading side to the trailing side. The blade includes a socket extending from the leading side of the blade and penetrating the cutter-supporting surface of the blade. The socket has a central axis, an open end at the leading side of the blade, and a closed end distal the leading side of the blade. The socket has (i) a first width W1 in a front view of the blade measured parallel to a projection of the cutter-supporting surface across the socket in the front view at a first distance D1 measured perpendicular to the projection of the cutter-supporting surface in the front view, and (ii) a second width W2 in a front view of the blade measured parallel to the projection of the cutter-supporting surface across the socket in the front view at a second distance D2 measured perpendicular to the projection of the cutter-supporting surface in the front view. The second distance D2 is greater than the first distance D1 and the second width W2 at the second depth D2 is greater than the first width W1 at the first width W1. In addition, the drill bit includes a cutter element assembly mounted to the blade and extending from the cutter-supporting surface of the blade. The cutter element assembly includes a cutter element carrier seated in the socket and fixably attached to the blade. The cutter element carrier includes a base that mates with the socket. The cutter element assembly also includes a cutter element fixably attached to the cutter element carrier.

A downhole drilling tool, forming part of a subterranean drilling system, may include at least one plate secured to an exterior of an elongate body. Electronics may be disposed between the plate and the body to be protected by the plate while still readily accessible. A dynamic element may be radially extendable from the plate to engage an inner wall of a borehole being drilled. If this radially-extendable element becomes worn or damaged from this engagement, the plate may be replaced. More expensive components of the drilling tool may be contained within the elongate body, rather than the plate, thus reducing replacement frequency. Additionally, plates including unique features may be employed at different times without altering the underlying elongate body.

The present invention provides a down-the-hole drill bit reaming structure, comprising a drill bit body, drill teeth embedded in the bottom of the drill bit body, an exhaust hole one provided in the drill bit body, the exhaust hole one being used to blow out debris and dust at the bottom of the hole, mounting grooves provided in a ring array on the side end of the drill bit body, a reaming assembly rotatably arranged in the mounting groove, a pneumatic assembly for driving the reaming assembly to rotate out and retract is further provided in the drill bit body, the pneumatic assembly is connected to the exhaust hole one, and by arranging the reaming assembly and the pneumatic assembly, when the drill bit body is drilling downward, the reaming assembly is extended to increase the diameter of the hole, and when the drilling is completed, the reaming assembly is retracted, so that the diameter of the drill bit body is smaller than the diameter of the casing, so that the drill bit body will not interfere with the casing when it moves back.

The invention discloses a variable-diameter drill bit for a rotary jet grouting anchor cable and a construction method, and the variable-diameter drill bit comprises a drill rod, an outer pipe, a jack, an adjustable drill bit and a supporting assembly; the fixed end of the jack is connected to the end of the drill rod, and the movable end of the jack is hinged to one end of the adjustable drill bit. A blade is arranged at the other end of the adjustable drill bit, and the cutting diameter of the adjustable drill bit can be adjusted through the jack; the supporting assembly is arranged on the outer side of the outer pipe. A supporting assembly is arranged on the outer side of the outer pipe, the movable end of the supporting assembly is connected with the adjustable drill bit, and when the adjustable drill bit conducts angle adjustment, the supporting assembly is configured to change the outer diameter of the supporting assembly, so that the hole channel is adaptively supported. The problems that in the prior art, the hole forming diameter of the rotary jet grouting anchor cable is uncontrollable, holes are prone to collapsing under the complex geology, the construction efficiency is low, and the anchor cable failure risk is high are solved, and the technical purposes of precise hole forming of the rotary jet grouting anchor cable and safe and efficient construction are achieved.

The invention belongs to the related technical field of ocean engineering, and discloses a horizontal ice drilling transmission mechanism based on a flexible shaft, which comprises a drill bit assembly, the flexible shaft, a sleeve joint chain, an upper end joint assembly, a lower end joint assembly and a guide pipe, the sleeve joint chain is formed by hinging a plurality of sleeve joints end to end through pin shafts and is accommodated in the guide pipe; a channel used for guiding and restraining the sleeve joint chain is arranged in the guide pipe. The flexible shaft is arranged in an inner cavity of the sleeve joint chain in a penetrating mode. The upper end of the flexible shaft is connected with an external rotation driving device through an upper end connector assembly. The upper end of the sleeve joint chain is connected with an external lifting driving device through an upper end connector assembly. The whole transmission mechanism is compact in structure and small in radial size, the space of a small-diameter vertical ice hole can be fully utilized, and large-depth drilling from the vertical direction to the horizontal direction is achieved; and a more stable and efficient drilling process can be realized, and the requirements of different ice layer hardness and drilling depth are met.

The present invention discloses a drilling mechanism for slope grouting reinforcement, which belongs to the technical field of drilling equipment. The mechanism comprises an engineering vehicle body, a drill bit assembly for drilling, and a carrier for carrying the drill bit assembly. A power structure for providing power to the drill bit assembly is slidably connected to the outer wall of the carrier. The output end of the power structure is connected to a transmission structure for extending the drilling depth. The transmission structure and the drill bit assembly are connected via a drilling structure. In the present invention, after the sliding direction of the limit frame is adjusted, the drive motor is turned on to drive the flywheel to rotate. During the rotation of the flywheel, the power rod is continuously hammered, thereby causing the power sleeve to rotate under the action of the casing, thereby driving the inner drill bit and the outer drill bit to rotate through the cooperation of the output rod and the transmission sleeve rod. In this way, not only can the drill bit assembly be continuously provided with rotational force, but also the drill bit assembly can be continuously provided with impact force, thereby increasing the drilling efficiency.

An anti-bouncing-sticking high-stability drill bit for drilling. The drill bit comprises: a drill bit body (1), cutting teeth (3), gauge teeth (4) and a plurality of blades (20), wherein the blades (20) are arranged on the drill bit body (1); each of the blades (20) has a main cutting portion and a gauge portion distributed in a direction from the center of the drill bit to the outside; the cutting teeth (3) are mounted on the main cutting portions; and the gauge teeth (4) are mounted on the gauge portions. The plurality of blades (20) comprise at least two helical blades (2); and in the helical blades (2), a helix angle β is formed between a line connecting a gauge point (51) of the main cutting portion to a gauge end point (61) of the gauge portion and a plane perpendicular to the axis of the drill bit, and satisfies 15°≤β≤60°. The technical problems of poor borehole trajectory quality and difficulty in ensuring wellbore wall quality which are caused by poor stability of the drill bit during the drilling process of the drill bit are solved.

The invention discloses self-adaptive variable-diameter drilling equipment for a high and cold frozen soil region and a stable-temperature construction method, and relates to the technical field of constructional engineering construction equipment, in particular to the self-adaptive variable-diameter drilling equipment for the high and cold frozen soil region, the self-adaptive variable-diameter drilling equipment comprises a main body, and the top of the main body is fixedly connected with a drilling assembly; a multi-blade structure is utilized, each blade is provided with an independent electric heating wire, the electric heating wires can preheat the blades in the drilling process, the blades are prevented from being embrittled due to low temperature, the service life of the drill bit is prolonged, the multiple telescopic auxiliary rotary drill bits are evenly distributed around the main drill bit, and the drilling efficiency is improved. The telescopic rod controls the auxiliary rotary drill bit to automatically adjust the telescopic length of the auxiliary rotary drill bit according to the hardness of the frozen soil layer and the drilling depth, so that the total diameter of the drill bit is changed to meet the drilling requirements of different diameters.