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CN-121976753-A - Split type concentric pipe-following drill bit

CN121976753ACN 121976753 ACN121976753 ACN 121976753ACN-121976753-A

Abstract

The invention relates to the technical field of drill bits and discloses a split concentric pipe-following drill bit which comprises a connecting seat, a drill bit body and a plurality of reaming sliding blocks, wherein a guide seat is arranged at the bottom of the connecting seat, a plurality of guide inclined surface grooves are formed in the circumferential direction of the guide seat, the guide inclined surface grooves incline to the axis of the guide seat from top to bottom, the drill bit body is covered on the guide seat, a first limiting block is arranged on the side wall of the connecting seat, a limiting long hole in sliding fit with the limiting block is formed in the drill bit body, the limiting long hole is arranged along the axial direction of the connecting seat, a matching groove is formed in the side wall of the drill bit body, the reaming sliding blocks are slidably arranged in the matching groove, and sliding block inclined surfaces in sliding fit with the guide inclined surface grooves are formed in the reaming sliding blocks.

Inventors

  • LUO WEN
  • Xue Keqin
  • ZHANG YONGFU
  • YU YONGNING
  • HOU YANWEI
  • WANG ZHIRONG
  • SHI LEI
  • GUO JIANLEI
  • JIANG TAO
  • WANG QI

Assignees

  • 国能神东煤炭集团有限责任公司
  • 中国神华能源股份有限公司神东煤炭分公司

Dates

Publication Date
20260505
Application Date
20260115

Claims (10)

  1. 1. The utility model provides a split type concentric pipe-following drill bit, its characterized in that, including connecting seat, bit body and a plurality of reaming slider, the bottom of connecting seat is equipped with the guide holder, the guide holder is equipped with a plurality of direction inclined plane grooves along circumference, direction inclined plane groove top-down to the central axis slope of guide holder, the bit body cover is established on the guide holder, be equipped with first stopper on the lateral wall of connecting seat, be equipped with on the bit body with first stopper sliding fit's spacing slot hole, spacing slot hole is followed the axial arrangement of connecting seat, the cooperation groove has been seted up to the lateral wall of bit body, reaming slider slidable sets up in the cooperation inslot, be equipped with on the reaming slider with direction inclined plane groove sliding fit's slider inclined plane, the top surface outside of reaming slider is equipped with from inside to outside downward sloping.
  2. 2. The split concentric casing bit of claim 1, wherein a second stop block is provided on a bottom of the mating groove, and wherein stop grooves are provided on the reamer block in sliding engagement with the second stop block, and wherein the stop grooves are disposed radially of the bit body.
  3. 3. The split concentric casing bit of claim 1, wherein the mating slot has a guide slot thereon, and the reaming slider has a third stop block slidably engaged with the guide slot, the guide slot being disposed radially of the bit body.
  4. 4. The split concentric casing drill according to claim 3 wherein two guide grooves are provided on either side of the mating groove, and the third stop block is semi-cylindrical.
  5. 5. The split concentric casing drill according to claim 1, wherein the outer wall of the connecting seat is provided with an ear seat groove, the drill body is provided with an ear seat in sliding fit with the ear seat groove, the limiting slot hole is formed in the ear seat, and the first limiting block is arranged in the ear seat groove.
  6. 6. The split concentric casing bit of claim 5, wherein the surface of the ear mount is lower than the surface of the connection mount when the ear mount is disposed in the ear mount channel.
  7. 7. The split concentric casing drill according to claim 1, wherein one end of the first stopper is in interference fit with the mounting hole of the connection seat, the other end of the first stopper is in a semicircle shape, the first stopper does not extend out of the long stopper hole, and the long stopper hole is in a waist-round shape.
  8. 8. The split concentric casing drill according to claim 2, wherein one end of the second stopper is in interference fit with the mounting hole of the mating groove, and the other end of the second stopper is hemispherical.
  9. 9. The split concentric casing bit of claim 1, wherein the connection block is a splined section.
  10. 10. The split concentric casing bit of claim 1, wherein the reaming blocks are three and equally circumferentially spaced.

Description

Split type concentric pipe-following drill bit Technical Field The invention relates to the technical field of drill bits, in particular to a split concentric casing drill bit. Background When complex stratum such as goaf, loose area, easy leakage and the like are drilled, the heel tube impact drilling technology is the most effective drilling method for realizing goaf penetration, loose stratum anti-collapse hole, leakage stratum leakage prevention and the like, and the bottom-expanding heel tube drill is a key component for realizing heel tube impact drilling. When the drill is used for carrying out impact drilling with a pipe, the impactor carries the drill bit to be downwards from the center of the sleeve to the bottom of the hole, and the outer diameter of the drill bit can be enlarged when the drilling pressure is applied, so that the sleeve can be smoothly downwards drilled when the drilling hole diameter is slightly larger than the outer diameter of the sleeve, and the outer diameter of the drill bit is contracted to be slightly smaller than the center hole of the sleeve when the drill is lifted, so that the drill can smoothly lift out of the drill hole and simultaneously keep the sleeve in the drill hole. However, the existing pipe-following drill bit has a plurality of defects in practical application, namely, for an eccentric pipe-following drill bit, larger torque is required to be applied to realize the expansion of the diameter of the drill bit, the torque fluctuation of the drill bit is caused by the formation lithology change in the drilling process, the problems of out-of-round hole and inconsistent aperture are further caused, the diameter of the drill bit is required to be reduced by reverse twisting during the starting of the drill bit, and safety accidents such as the breaking out and the falling of the drill bit are easily caused. For concentric reaming slider formula with pipe drill bit, its reaming slider easily breaks under high frequency impact load, and the easy slider fit clearance that gets into of drilling slag leads to the card to block simultaneously, causes the slider unable flexible in place, influences with pipe and carries the operation of boring. In addition, the existing pipe-following drill bit is of an integral structure, the spline section of the impact drill bit is usually intact, but the drill bit body is worn out rapidly due to direct contact with stratum, and the use cost is high due to integral scrapping. Disclosure of Invention The invention aims to provide a split concentric casing drill bit, which is capable of improving shock resistance, reducing use cost and guaranteeing hole forming quality and operation reliability of casing drilling of complex stratum. In order to achieve the above purpose, the invention provides a split concentric pipe-following drill bit, which comprises a connecting seat, a drill bit body and a plurality of reaming sliding blocks, wherein the bottom of the connecting seat is provided with a guide seat, the guide seat is circumferentially provided with a plurality of guiding inclined surface grooves, the guiding inclined surface grooves incline to the central axis of the guide seat from top to bottom, the drill bit body is covered on the guide seat, the side wall of the connecting seat is provided with a first limiting block, the drill bit body is provided with a limiting long hole in sliding fit with the first limiting block, the limiting long hole is arranged along the axial direction of the connecting seat, the side wall of the drill bit body is provided with a matching groove, the reaming sliding blocks are slidably arranged in the matching groove, the reaming sliding blocks are provided with sliding block inclined surfaces which are in sliding fit with the guiding inclined surface grooves, and the outer side of the top surface of each reaming sliding block is provided with a guiding inclined surface which inclines from inside to outside. As a preferable scheme of the invention, a second limiting block is arranged at the bottom of the matching groove, a limiting groove which is in sliding fit with the second limiting block is arranged on the reaming slider, and the limiting groove is arranged along the radial direction of the drill bit body. As a preferable scheme of the invention, the matching groove is provided with a guide groove, the reaming slide block is provided with a third limiting block which is in sliding fit with the guide groove, and the guide groove is arranged along the radial direction of the drill bit body. As a preferable scheme of the invention, two guide grooves are arranged on two sides of the matching groove, and the third limiting block is semi-cylindrical. As a preferable scheme of the invention, the outer wall of the connecting seat is provided with an ear seat groove, the drill bit body is provided with an ear seat which is in sliding fit with the ear seat groove, the limiting long hole is arranged on the