Anti-deflection drilling device for shield receiving vertical freezing hole and construction method

Abstract

The invention relates to the technical field of well drilling, and discloses an anti-deflection drilling device for receiving a vertical freezing hole by a shield machine and a construction method.The anti-deflection drilling device for receiving the vertical freezing hole by the shield machine comprises a drill bit, and a drilling tool section, an anti-deflection unit and a flexible section are sequentially connected to the upper portion of the drill bit; each anti-deflection unit comprises a heavy drooping section and a pair of deviation rectifying sections symmetrically arranged at the two ends of the heavy drooping section, telescopic deviation rectifying blocks are arranged on the deviation rectifying sections, stretching and retracting of the deviation rectifying blocks are pushed by flowing of mud, the structures on the two deviation rectifying sections are completely the same, and a heavy drooping rod is arranged in the center of each heavy drooping section and used for controlling stretching and retracting of the corresponding deviation rectifying block. According to the anti-deflection drilling device for the shield receiving vertical freezing hole, through the anti-deflection unit, when the heavy plumbing joint deflects, the heavy plumbing rod in the heavy plumbing joint is always vertical, the two deviation rectifying blocks close to the two ends of the heavy plumbing rod are controlled to stretch out, the anti-deflection unit is righting from the two centrosymmetric directions, and then a drill bit is righting.

Description

Technical Field

[0001] The invention relates to the technical field of drilling, and in particular to an anti-deflection drilling device for a shield receiving a vertical freezing hole and a construction method. Background Art

[0002] The shield receiving freezing hole refers to the process of using freezing method to reinforce the soil when the shield machine approaches the tunnel end (usually the end or starting point of the shield machine's advancement) during the shield tunnel construction process to ensure that the shield machine successfully completes the receiving operation. The freezing hole is a key structure used in the freezing method. By drilling holes in the soil near the receiving end and injecting freezing liquid, the soil is frozen into a stable frozen soil wall or frozen soil block, thereby providing sufficient support to prevent soil collapse or groundwater leakage.

[0003] The patent publication number CN216111424U discloses an automatic anti-deflection drilling device, which includes a drill collar body, one end of the drill collar body is a drill collar body support section, a piston cavity is provided, and a through hole is provided to connect the piston cavity with the inner cavity of the drill collar body, and a piston is matched in the piston cavity. An eccentric sleeve is axially fixedly sleeved at the other end of the drill collar body, and a semi-circular annular groove is provided on the inner wall of the eccentric sleeve, and a semi-circular annular groove is also provided on the outer wall of the drill collar body. The annular cavity formed by these two semi-circular annular grooves is filled with a plurality of steel balls. The outer diameter of the eccentric sleeve support block is larger than the outer diameter of the drill collar body support section, and the outer diameter of the other parts of the eccentric sleeve is smaller than the outer diameter of the drill collar body support section. The center of gravity edge of the eccentric sleeve is at a certain angle to the support block. According to the tumbler principle and the lever principle, the drilling tool can automatically generate a large deflection reduction force, thereby preventing the wellbore from deflecting.

[0004] The prior art has the following defects:

[0005] Existing anti-well deflection devices often straighten the tilted drill pipe in a single direction, but the straightening force is insufficient and the drill pipe needs to rotate at a fixed speed. When facing different geological layers, different drilling speeds are usually selected. Therefore, there is a certain uncertainty in correcting the deviation by centrifugal force. Summary of the invention

[0006] In view of the above problems in the prior art, a construction method for preventing deflection of a vertical freezing hole received by a shield machine is proposed.

[0007] On the one hand, the present application provides a deflection-proof drilling device for a shield machine to receive a vertical freezing hole, the purpose of which is to automatically apply force in the central symmetric direction to correct the deviation during the drilling process, solve the well inclination problem in multiple directions, and avoid lifting the drill bit multiple times to measure the slope.

[0008] The technical solution of the present invention is: a device for drilling a vertical freezing hole for shield tunneling, comprising a drill bit, a drill tool section, an anti-deflection unit, and a flexible section connected in sequence above the drill bit;

[0009] The anti-deflection unit includes a weight vertical joint and a pair of correcting joints symmetrically arranged at both ends of the weight vertical joint, the correcting joint is provided with a retractable correcting block, the extension and retraction of the correcting block is driven by the flow of mud, the structures on the two groups of the correcting joints are exactly the same, a weight vertical rod is provided at the center of the weight vertical joint, the midpoint of the weight vertical rod rotates freely at the center of the weight vertical joint, and the weight vertical rod is used to control the extension of the correcting block; when there is deflection in the drilling, the weight vertical rod always has a tendency to rotate to a vertical direction due to gravity, and the weight vertical rod controls the correcting block on the lower correcting joint on the high side of the deflection and the correcting block on the upper correcting joint on the low side of the deflection to extend, and the anti-deflection unit is straightened from two directions symmetrically about the center of the weight vertical joint.

[0010] By adopting the above scheme, when the weight plumb joint is deflected, the weight plumb rod inside it is always vertical through the anti-deflection unit, and the two correction blocks close to the two ends of the weight plumb rod are controlled to extend, so as to straighten the anti-deflection unit from two directions that are centrally symmetrical, and then straighten the drill bit; the vertical state of the weight plumb rod is used to trigger the straightening, and there is no need to access the electrical control system, which is suitable for various complex scenarios.

[0011] Furthermore, a positioning step is provided in the middle of the weight plumb joint, a positioning ring is provided on the positioning step, a spherical groove is opened at the center of the positioning ring, a rotating ball is rotatably provided in the spherical groove, and the upper and lower parts of the rotating ball are exposed outside the spherical groove, the midpoint of the weight plumb rod is fixed at the center of the rotating ball, and the two ends of the weight plumb rod extend to the two groups of deviation correction joints respectively, a locking ring is provided above the positioning ring, the locking ring cooperates with the inner wall thread of the weight plumb joint and presses the positioning ring against the positioning step, and a counterweight block is provided in the lower half of the weight plumb rod.

[0012] By adopting the above scheme, the center of the rotating ball is rotated at the center of the weight plumb joint by positioning the positioning ring at the center of the weight plumb joint, and the weight plumb rod connected thereto is always rotated in the vertical direction under the action of the counterweight block, thereby controlling the correction block away from the weight plumb rod to extend, and straightening the anti-deflection unit from two directions symmetrically about the center of the weight plumb joint.

[0013] Furthermore, four groups of cylindrical shells are arranged at equal angles on the outer wall of the correction section, the correction block slides in the cylindrical shell, the side wall of the correction block is in close contact with the inner wall of the cylindrical shell, the sliding direction of the correction block is perpendicular to the axis of the weight vertical section, and a connecting hole is arranged on the side wall of the correction section, the connecting hole connects the inner cavity of the correction section and the inner cavity of the cylindrical shell.

[0014] By adopting the above scheme, four groups of cylindrical shells are set up, and four groups of correction blocks are made to slide in the cylindrical shells, so that the deviated heavy vertical joints can be corrected in four directions, making the correction of the deviated drill bit more accurate.

[0015] Furthermore, a square section is provided at the end of the weighted vertical rod, and two groups of rectangular frames perpendicular to each other are sleeved on the square section. One group of opposite sides of the rectangular frame slides close to the square section, and there is a gap between the other group of opposite sides and the rectangular frame. The sliding directions of the two groups of rectangular frames are perpendicular to each other. Symmetrical arc rods are provided on both sides of the long sides of each group of rectangular frames. The arc rods in symmetrical positions are respectively inserted into matching and symmetrical connecting holes. The depth of the arc rods inserted into the connecting holes is just enough to block the connecting holes. The axis of each group of arc rods passes through a circle of the same size with the center of the rotating ball as the center. An arc notch is provided on each pair of arc rods, so that relative displacement can be generated between each pair of arc rods and the rectangular frame on the opposite side.

[0016] By adopting the above scheme, a rectangular frame and an arc rod are set up, so that the two pairs of arc rods in a vertical state can independently control the extension of the two pairs of correction blocks in a vertical state, so that the correction blocks in the front and back and left and right directions can work independently. Through the combination of the extension of adjacent correction blocks, the heavy vertical joint can be corrected in a maximum of eight directions.

[0017] Furthermore, the communicating hole is arc-shaped, and its axis is on the same circle as the axis of the arc-shaped rod inserted therein, and the arc-shaped rod can slide in the communicating hole that matches it.

[0018] By adopting the above scheme, the arc rod can slide in the matching connecting hole, so that the arc rod on one side can slide deeply into the connecting hole, and the arc rod on the opposite side can be separated from the connecting hole, so that mud can pass through the connecting hole and push the correction block to extend.

[0019] Furthermore, a sliding cavity is arranged in the cylindrical shell, and the sliding cavity is composed of two cylindrical cavities with different diameters. The cavity diameter at the opening is larger, and a limiting ring is arranged at the opening of the sliding cavity. The limiting ring and the sliding cavity are threadedly matched. The correcting block is composed of two cylinders with different diameters. The cylinder with a smaller diameter is on the outside, and its diameter is the same as the inner diameter of the limiting ring. The diameter of the cylinder with a larger diameter is the same as the larger diameter of the sliding cavity. A pressure relief hole is opened on the correcting block, and the diameter of the pressure relief hole is smaller than the diameter of the connecting hole.

[0020] By adopting the above scheme, a sliding cavity and a limit ring are set to restrict the sliding of the correction block in the sliding cavity. By setting the diameter of the pressure relief hole to be smaller than the diameter of the connecting hole, the mud flowing into the connecting hole is greater than the mud flowing out of the pressure relief hole. The flow difference of the mud generates pressure to cause the correction block to withdraw from the sliding cavity.

[0021] Furthermore, a threaded section is provided at the end of the square section, and a conical cap is matched on the threaded section.

[0022] By adopting the above scheme, the conical cap is provided to limit the position of the rectangular frame and divert the mud, thereby preventing the mud from eroding the heavy vertical rod.

[0023] Furthermore, another aspect of the present invention provides a method for preventing deflection of a shield receiving vertical freezing hole, comprising the following steps:

[0024] Step 1: Prepare mud in the mud tank according to the formation properties and drilling requirements, and use a mud pump to transport it into the borehole;

[0025] Step 2: Install the drill rod, drill bit and other drilling tools on the drilling rig, and check the linearity of the drill rod; align the drill tools with the drilling position by adjusting the position and angle of the drilling rig.

[0026] Step 3: Start the drilling rig, rotate the drill bit slowly, and the drill bit begins to touch the ground. In the initial drilling, control the drilling speed and gradually deepen the hole; start the mud pump to pump the prepared mud into the hole through the drill pipe; the mud circulates in the hole, takes the cuttings out of the hole through the nozzle of the drill bit, and keeps the hole wall stable;

[0027] Step 4: During the drilling process, continue to pump mud and keep the mud circulating to ensure that the drill bit is always adequately lubricated and cooled; maintain appropriate drilling pressure and speed during operation;

[0028] Step 5: After the drilling depth reaches 5-10m, lift the drill rod, install the anti-deflection drilling device for the shield receiving vertical freezing hole between the drill bit and the drill rod adjacent to the drill bit, and then continue drilling. When the drilling is deflected, the correction block on the lower correction section on the high side of the deflection and the correction block on the upper correction section on the low side of the deflection extend out, and the anti-deflection unit is corrected from two directions symmetrically about the center of the heavy vertical section, and the anti-deflection unit then drives the drill bit to correct;

[0029] Step 6: As the hole gets deeper, you need to add drill rods in sections. After each section is drilled, stop drilling, lift the drill, connect the next section of drill rod, and continue drilling.

[0030] By adopting the above scheme, the anti-deflection drilling device for shield receiving vertical freezing holes is connected after pre-drilling, so that the drill bit can automatically correct the deviation during deep drilling, ensuring that the verticality of the wellbore meets the technical requirements.

[0031] Beneficial effects of the present invention:

[0032] 1. Through the anti-deflection unit, when the weight plumb joint is deflected, the weight plumb rod inside it is always vertical, and the two correction blocks close to the two ends of the weight plumb rod are controlled to extend, and the anti-deflection unit is straightened from two directions that are centrally symmetrical, and then the drill bit is straightened; the vertical state of the weight plumb rod is used for straightening triggering, and no electrical control system access is required, which is suitable for various complex scenarios.

[0033] 2. By setting four groups of cylindrical shells, four groups of correction blocks slide in the cylindrical shells, so as to correct the deflected heavy vertical joint in four directions, making the correction of the deflected drill bit more accurate.

[0034] 3. By setting a rectangular frame and an arc rod, the two pairs of arc rods in a vertical state can independently control the extension of the two pairs of correction blocks in a vertical state, so that the correction blocks in the front and back and left and right directions can work independently. Through the combination of adjacent correction blocks extending at different distances, the heavy vertical joint can be corrected in any direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A stereoscopic diagram of the anti-deflection drilling device for receiving a vertical freezing hole for a shield machine according to the present invention;

[0036] Figure 2 A stereoscopic diagram of an anti-deflection unit in an anti-deflection drilling device for receiving a vertical freezing hole of a shield machine according to the present invention;

[0037] Figure 3 It is a top view of the anti-deflection unit in the anti-deflection drilling device for receiving a vertical freezing hole of a shield machine according to the present invention;

[0038] Figure 4 For the present invention Figure 3 Sectional view at AA;

[0039] Figure 5 For the present invention Figure 4 Sectional view at the middle BB;

[0040] Figure 6 This is a structural diagram of the end portion of the heavy vertical rod in the anti-deflection drilling device for receiving a vertical freezing hole of a shield machine according to the present invention;

[0041] Figure 7 For the present invention Figure 6 Exploded diagram of

[0042] Figure 8 This is a working principle diagram of the anti-deflection unit in the anti-deflection drilling device for receiving a vertical freezing hole of a shield machine according to the present invention;

[0043] Fig. 9 For the present invention Figure 8 Enlarged schematic diagram at point C in the middle.

[0044] In the figure:

[0045] 1. Drill bit; 2. Drill tool section; 3. Anti-deflection unit; 4. Flexible section; 5. Weight-lifting section; 6. Correction section; 7. Correction block; 8. Weight-lifting rod; 9. Positioning step; 10. Positioning ring; 11. Spherical groove; 12. Rotating ball; 13. Locking ring; 14. Counterweight; 15. Cylindrical shell; 16. Connecting hole; 17. Square section; 18. Rectangular frame; 19. Arc rod; 20. Arc notch; 21. Sliding cavity; 22. Limiting ring; 23. Pressure relief hole; 24. Conical cap. DETAILED DESCRIPTION

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0047] Example 1

[0048] Reference Figure 1-9 , which is the first embodiment of the present invention, provides a shield machine for receiving a vertical freezing hole to prevent deflection drilling device, comprising a drill bit 1, and a drill tool section 2, an anti-deflection unit 3, and a flexible section 4 are sequentially connected above the drill bit 1;

[0049] The anti-deflection unit 3 includes a weight vertical joint 5 and a pair of correcting joints 6 symmetrically arranged at both ends of the weight vertical joint 5. A retractable correcting block 7 is arranged on the correcting joint 6. The extension and retraction of the correcting block 7 is driven by the flow of mud. The structures of the two groups of correcting joints 6 are exactly the same. A weight vertical rod 8 is arranged at the center of the weight vertical joint 5. The midpoint of the weight vertical rod 8 rotates freely at the center of the weight vertical joint 5. The weight vertical rod 8 is used to control the extension of the correcting block 7. When the drilling is deflected, the weight vertical rod 8 always has a tendency to rotate to a vertical direction due to gravity. The weight vertical rod 8 controls the correcting block 7 on the lower correcting joint 6 on the high side of the deflection and the correcting block 7 on the upper correcting joint 6 on the low side of the deflection to extend, and the anti-deflection unit 3 is straightened from two directions symmetrically about the center of the weight vertical joint 5.

[0050] Specifically, the flexible section 4 is connected to the drill rod above, and the flexible section 4 has a certain degree of bending, which can make the anti-deflection unit 3 deflect at a certain angle relative to the drill rod, thereby playing a role in straightening and guiding the upper drill rod. The drill section 2, the anti-deflection unit 3, and the flexible section 4 are all hollow tubes. Mud is pumped into the cavity by a mud pump and flows out from the drill bit 1. The mud is used as a flushing medium to carry away the rock cuttings generated during the drilling process and maintain the stability of the borehole. The drill bit 1, the drill section 2, the anti-deflection unit 3, and the flexible section 4 are all connected by a tapered thread.

[0051] Through the anti-deflection unit 3, when the weight plumb joint 5 is deflected, the weight plumb rod 8 inside it is always vertical, and the two correction blocks 7 close to the two ends of the weight plumb rod 8 are controlled to extend, so as to straighten the anti-deflection unit 3 from two directions that are centrally symmetrical, and then straighten the drill bit 1; the vertical state of the weight plumb rod 8 is used to trigger the straightening, and there is no need to access the electrical control system, which is suitable for various complex scenarios.

[0052] Reference Figure 4 A positioning step 9 is provided in the middle of the weight plumb joint 5, and a positioning ring 10 is provided on the positioning step 9. A spherical groove 11 is opened at the center of the positioning ring 10. A rotating ball 12 is rotatably provided in the spherical groove 11, and the upper and lower parts of the rotating ball 12 are exposed outside the spherical groove 11. The midpoint of the weight plumb rod 8 is fixed at the center of the rotating ball 12, and the two ends of the weight plumb rod 8 extend into the two groups of deviation correction joints 6 respectively. A locking ring 13 is provided above the positioning ring 10, and the locking ring 13 cooperates with the inner wall thread of the weight plumb joint 5 to tighten the positioning ring 10 and the positioning step 9. A counterweight block 14 is provided in the lower half of the weight plumb rod 8.

[0053] Specifically, the rotating ball 12 slides closely in the spherical groove 11, and a plurality of through holes are vertically opened on the positioning ring 10 for mud to pass through the positioning ring 10. Since a counterweight block 14 is provided in the lower half of the weight vertical rod 8, as the weight vertical section 5 tilts, the weight vertical rod 8 always points to the vertical direction.

[0054] By positioning the positioning ring 10 at the center of the weight plumb joint 5, the center of the rotating ball 12 is rotated at the center of the weight plumb joint 5, and the weight plumb rod 8 connected thereto is always rotated in the vertical direction under the action of the counterweight block 14, thereby controlling the correction block 7 away from the weight plumb rod 8 to extend, and straightening the anti-deflection unit 3 from two directions symmetrically about the center of the weight plumb joint 5.

[0055] Reference Figure 4 Four groups of cylindrical shells 15 are arranged at equal angles on the outer wall of the correcting section 6, the correcting block 7 slides in the cylindrical shell 15, the side wall of the correcting block 7 is in close contact with the inner wall of the cylindrical shell 15, the sliding direction of the correcting block 7 is perpendicular to the axis of the weight vertical section 5, and a connecting hole 16 is arranged on the side wall of the correcting section 6, the connecting hole 16 connects the inner cavity of the correcting section 6 and the inner cavity of the cylindrical shell 15.

[0056] Specifically, the outer diameter of the cylindrical shell 15 is slightly smaller than the outer diameter of the correcting section 6, each correcting section 6 occupies one quarter of the arc of the outer diameter of the correcting section 6, and the inner diameter of the correcting section 6 is smaller than the inner diameter of the weight vertical section 5. When the mud passes through the correcting section 6, the pressure increases, and the mud enters the cylindrical shell 15 through the connecting hole 16, and pushes the correcting block 7 to extend out of the cylindrical shell 15.

[0057] By providing four groups of cylindrical shells 15, four groups of deviation-correcting blocks 7 are slid in the cylindrical shells 15, so that the deflected vertical joint 5 can be corrected in four directions, making the correction of the deflected drill bit 1 more accurate.

[0058] Reference Figure 6-Figure 7 A square section 17 is provided at the end of the weight vertical rod 8, and two groups of rectangular frames 18 are sleeved on the square section 17, and one group of opposite sides of the rectangular frame 18 slides close to the square section 17, and there is a gap between the other group of opposite sides and the rectangular frame 18. The sliding directions of the two groups of rectangular frames 18 are perpendicular to each other. Symmetrical arc rods 19 are provided on both sides of the long sides of each group of rectangular frames 18. The arc rods 19 in symmetrical positions are respectively inserted into the connecting holes 16 that match and are symmetrical to each other. The depth of the arc rods 19 inserted into the connecting holes 16 can just block the connecting holes 16. The axis of each group of arc rods 19 passes through a circle of the same size with the center of the rotating ball 12 as the center. An arc notch 20 is opened on each pair of arc rods 19, so that relative displacement can be generated between each pair of arc rods 19 and the rectangular frame 18 on the opposite side.

[0059] Specifically, since symmetrical arc rods 19 are provided on both sides of the long sides of each group of rectangular frames 18, when the weighted vertical rod 8 swings along the axial direction of each pair of arc rods 19, it drives a pair of arc rods 19 to swing together, and when the weighted vertical rod 8 swings in the direction perpendicular to the axis of each pair of arc rods 19, it causes relative displacement with the pair of arc rods 19, that is, when the weighted vertical rod 8 swings in the left and right directions, it only drives the arc rods 19 in the left and right directions to swing; when the weighted vertical rod 8 swings in the front and back directions, it only drives the arc rods 19 in the front and back directions to swing; when the weighted vertical rod 8 swings in the oblique direction, it drives the arc rods 19 in the front and back and left and right directions to swing at the same time; when the arc rod 19 swings toward one side of the connecting hole 16, the connecting hole 16 on the opposite side opens, and the corresponding deviation correction block 7 extends out.

[0060] By setting the rectangular frame 18 and the arc rod 19, the two pairs of arc rods 19 in the vertical state can independently control the extension of the two pairs of correcting blocks 7 in the vertical state, so that the correcting blocks 7 in the front and back and left and right directions can work independently. Through the combination of the extended adjacent correcting blocks 7, the weight vertical joint 5 can be corrected in a maximum of eight directions.

[0061] Reference Fig. 9 The connecting hole 16 is arc-shaped, and its axis is on the same circle as the axis of the arc-shaped rod 19 inserted therein, and the arc-shaped rod 19 can slide in the connecting hole 16 matched therewith.

[0062] The arc rod 19 can slide in the matching connecting hole 16, so that the arc rod 19 on one side can slide deeply into the connecting hole 16, and the arc rod 19 on the opposite side can be separated from the connecting hole 16, so that mud can pass through the connecting hole 16 and push the correcting block 7 to extend.

[0063] Reference Fig. 9 A sliding cavity 21 is arranged in the cylindrical shell 15, and the sliding cavity 21 is composed of two cylindrical cavities with different diameters. The cavity diameter at the opening is larger. A limiting ring 22 is arranged at the opening of the sliding cavity 21, and the limiting ring 22 is threadedly matched with the sliding cavity 21. The correcting block 7 is composed of two cylinders with different diameters. The cylinder with a smaller diameter is on the outside, and its diameter is the same as the inner diameter of the limiting ring 22. The diameter of the cylinder with a larger diameter is the same as the larger diameter of the sliding cavity 21. A pressure relief hole 23 is opened on the correcting block 7, and the diameter of the pressure relief hole 23 is smaller than the diameter of the connecting hole 16.

[0064] Specifically, since the bottom surface of the correcting block 7 is engaged with the cavity wall of the sliding cavity 21 with a smaller diameter, a cavity area is formed at the bottom of the correcting block 7. The mud flowing into the cavity area will squeeze the bottom of the correcting block 7 and push the small cylinder of the correcting block 7 out of the limit ring 22.

[0065] By setting the sliding cavity 21 and the limit ring 22, the correction block 7 is restricted to slide in the sliding cavity 21. By setting the diameter of the pressure relief hole 23 to be smaller than the diameter of the connecting hole 16, the mud flowing into the connecting hole 16 is greater than the mud flowing out of the pressure relief hole 23. The flow difference of the mud generates pressure to pull the correction block 7 out of the sliding cavity 21.

[0066] Reference Figure 6-Figure 7 A threaded section is provided at the end of the square section 17, and a conical cap 24 is fitted on the threaded section.

[0067] The conical cap 24 is provided to limit the position of the rectangular frame 18 and to divert mud, thereby preventing the mud from eroding the heavy vertical rod 8.

[0068] Example 2

[0069] As a second embodiment of the present invention, there is provided: a construction method for preventing deflection of a vertical freezing hole received by a shield machine, using a drilling device for preventing deflection of a vertical freezing hole received by a shield machine, comprising the following steps:

[0070] Step 1: Prepare mud in the mud tank according to the formation properties and drilling requirements, and use a mud pump to transport it into the borehole;

[0071] Step 2: Install the drill rod, drill bit 1 and other drilling tools on the drilling rig, ensure that the connection is firm and avoid looseness, check the linearity of the drill rod to avoid bending that affects the drilling process; align the drill tool with the drilling position by adjusting the position and angle of the drilling rig.

[0072] Step 3: Start the drilling rig, rotate the drill bit slowly, and the drill bit 1 begins to contact the ground. In the initial drilling, control the drilling speed and gradually deepen the borehole; start the mud pump to pump the prepared mud into the borehole through the drill pipe; the mud circulates in the borehole, takes the cuttings out of the borehole through the nozzle of the drill bit 1, and keeps the borehole wall stable;

[0073] Step 4: During the drilling process, continue to pump the mud and keep the mud circulating to ensure that the drill bit 1 is always sufficiently lubricated and cooled; maintain appropriate drilling pressure and speed during operation to avoid excessive or insufficient drilling pressure affecting the drilling efficiency;

[0074] Step 5: After the drilling depth reaches 5m, the drill rod is lifted, and an anti-deflection drilling device for shield receiving vertical freezing holes is installed between the drill bit 1 and the drill rod adjacent to the drill bit 1, and then drilling is continued. When the drilling is deflected, the correcting block 7 on the lower correcting section 6 on the high side of the deflection and the correcting block 7 on the upper correcting section 6 on the low side of the deflection extend out, and the anti-deflection unit 3 is straightened from two directions symmetrically about the center of the weight vertical section 5, and the anti-deflection unit then drives the drill bit 1 to straighten;

[0075] Step 6: As the hole gets deeper, you need to add drill rods in sections. After each section is drilled, stop drilling, lift the drill, connect the next section of drill rod, and continue drilling.

[0076] After pre-drilling, the anti-deflection drilling device for receiving the vertical freezing hole of the shield machine is connected, so that the drill bit 1 can automatically correct the deviation during the deep drilling process to ensure that the verticality of the well hole meets the technical requirements.

[0077] Before drilling, the site should be leveled to facilitate the adjustment of the drilling rig angle. At the same time, a 0.3m high retaining wall should be built outside the drilling area to prevent the drilling mud from flowing out and polluting the environment, and to facilitate the circulation of bentonite.

[0078] Specifically, the tunnel centerline released by the surveying team is used as the reference line, and the freezing hole positions are placed according to the freezing hole position detailed drawing. The hole positions need to be checked during drilling and only drilled after they are correct. For vertical freezing hole construction, mud wall drilling is first performed, and after reaching the drilling depth, the freezing pipe is lowered. The freezing pipe connection adopts the external pipe clamp + welding method.

[0079] The drill bit 1 adopts a roller drill bit 1 or a three-wing drill bit 1, and a GXY-200C drilling rig with strong drilling ability is selected, with a motor power of 18.5KW / unit; a BW-250 mud pump is selected for mud circulation, with a motor power of 15KW / unit, and light is used for inclination measurement.

[0080] In order to ensure the drilling accuracy, the drilling of the opening section is the key. When drilling the first 5m, the verticality of the drill rod should be repeatedly checked, and the angle should be adjusted if there is any deviation. After it is correct, the drilling rig should be reinforced again.

[0081] During the drilling process, the vibration of the drill rig may cause the angle to shift. When half of the hole is drilled, it is necessary to meet the drilling angle again. If the angle is normal, continue drilling. If the angle deviates, the drill rig angle needs to be fine-tuned and the drill rig needs to be reinforced before continuing drilling. If the angle shifts significantly, it is necessary to drill a supplementary hole or pull out the freezing pipe, adjust the angle and then drill again.

[0082] Before the freezing pipe is lowered into the drilled hole, it is necessary to install the pipe first to ensure the length of the freezing pipe; the freezing pipes are installed one by one. Before welding, check that the concentric axes of the freezing pipes coincide. When welding, the welds must be full. If necessary, the pipe clamps should be vertically grooved to strengthen the welding and increase the connection strength to avoid breakage of the freezing pipe welds when pulling out the pipe. After the pipe joint is installed, seal the pipe opening with a wooden plug to prevent foreign matter from falling into the freezing pipe.

[0083] Reference Figure 8-Figure 9 Working principle of the present invention:

[0084] Through the anti-deflection unit 3, when the weight vertical joint 5 is deflected, the weight vertical rod 8 inside it is always vertical, and the weight vertical rod 8 swings relative to the weight vertical joint 5. When the arc rod 19 swings toward the low-side connecting hole 16, the connecting hole 16 on the opposite side is opened, and the corresponding correcting block 7 is pushed out by the mud. In a group of symmetrical correcting sections 6, the correcting block 7 on the lower correcting section 6 on the deflected high side and the correcting block 7 on the upper correcting section 6 on the deflected low side extend out to straighten the anti-deflection unit 3 from two directions symmetrically about the center of the weight vertical joint 5.

[0085] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A device for drilling a vertical freezing hole for shield tunneling, comprising a drill bit (1), characterized in that: The drill bit (1) is sequentially connected to a drill tool section (2), an anti-deflection unit (3), and a flexible section (4); The anti-deflection unit (3) comprises a weight vertical joint (5) and a pair of correction joints (6) symmetrically arranged at both ends of the weight vertical joint (5); a retractable correction block (7) is arranged on the correction joint (6); the extension and retraction of the correction block (7) is driven by the flow of mud; the structures of the two groups of correction joints (6) are completely the same; a weight vertical rod (8) is arranged at the center of the weight vertical joint (5); the midpoint of the weight vertical rod (8) rotates freely at the center of the weight vertical joint (5); the weight vertical rod (8) is used to control the extension of the correction block (7); when the drilling is deflected, the weight vertical rod (8) always has a tendency to rotate to a vertical direction due to gravity; the weight vertical rod (8) controls the correction block (7) on the lower correction joint (6) on the higher side of the deflection and the correction block (7) on the upper correction joint (6) on the lower side of the deflection to extend, and the anti-deflection unit (3) is straightened from two directions symmetrically about the center of the weight vertical joint (5).

2. The device for preventing deflection of a vertical freezing hole received by a shield machine according to claim 1 is characterized in that: A positioning step (9) is arranged in the middle of the weight vertical joint (5), a positioning ring (10) is arranged on the positioning step (9), a spherical groove (11) is opened at the center of the positioning ring (10), a rotating ball (12) is rotatably arranged in the spherical groove (11), and the upper and lower parts of the rotating ball (12) are exposed outside the spherical groove (11), the midpoint of the weight vertical rod (8) is fixed at the center of the rotating ball (12), and the two ends of the weight vertical rod (8) extend into the two groups of deviation correction joints (6) respectively, a locking ring (13) is arranged above the positioning ring (10), the locking ring (13) is matched with the inner wall thread of the weight vertical joint (5) and presses the positioning ring (10) against the positioning step (9), and a counterweight block (14) is arranged in the lower half of the weight vertical rod (8).

3. The device for preventing deflection of a vertical freezing hole received by a shield machine according to claim 2 is characterized in that: Four groups of cylindrical shells (15) are arranged at equal angles on the outer wall of the deflection correcting section (6); the deflection correcting block (7) slides in the cylindrical shell (15); the side wall of the deflection correcting block (7) is in close contact with the inner wall of the cylindrical shell (15); the sliding direction of the deflection correcting block (7) is perpendicular to the axis of the weight vertical section (5); a connecting hole (16) is arranged on the side wall of the deflection correcting section (6); the connecting hole (16) connects the inner cavity of the deflection correcting section (6) and the inner cavity of the cylindrical shell (15).

4. The device for preventing deflection of a shield tunnel receiving a vertical freezing hole according to claim 3 is characterized in that: The end of the weight vertical rod (8) is provided with a square section (17), and two groups of rectangular frames (18) are sleeved on the square section (17) in directions perpendicular to each other. One group of opposite sides of the rectangular frame (18) slides close to the square section (17), and there is a gap between the other group of opposite sides and the rectangular frame (18). The sliding directions of the two groups of rectangular frames (18) are perpendicular to each other. Symmetrical arc rods (19) are provided on both sides of the long sides of each group of rectangular frames (18). The arc rods (19) in symmetrical positions are respectively inserted into the connecting holes (16) that match and are symmetrical to each other. The depth of the arc rods (19) inserted into the connecting holes (16) is just enough to block the connecting holes (16). The axis of each group of arc rods (19) passes through a circle of the same size with the center of the rotating ball (12) as the center. An arc notch (20) is opened on each pair of arc rods (19), so that relative displacement can be generated between each pair of arc rods (19) and the rectangular frame (18) on the opposite side.

5. The device for preventing deflection of a shield tunnel receiving a vertical freezing hole according to claim 4 is characterized in that: The communicating hole (16) is arc-shaped, and its axis is on the same circle as the axis of the arc-shaped rod (19) inserted therein, and the arc-shaped rod (19) slides in the communicating hole (16) matched therewith.

6. The device for preventing deflection of a shield tunnel receiving a vertical freezing hole according to claim 3, characterized in that: A sliding cavity (21) is arranged in the cylindrical shell (15), and the sliding cavity (21) is composed of two cylindrical cavities with different diameters. The cavity diameter at the opening is larger. A limit ring (22) is arranged at the opening of the sliding cavity (21), and the limit ring (22) and the sliding cavity (21) are threadedly matched. The correction block (7) is composed of two cylinders with different diameters. The cylinder with a smaller diameter is on the outside, and its diameter is the same as the inner diameter of the limit ring (22). The cylinder with a larger diameter has a diameter that is the same as the larger diameter of the sliding cavity (21). A pressure relief hole (23) is opened on the correction block (7), and the diameter of the pressure relief hole (23) is smaller than the diameter of the connecting hole (16).

7. The device for preventing deflection of a shield tunnel receiving a vertical freezing hole according to claim 4, characterized in that: The end of the square segment (17) is provided with a threaded segment, and a conical cap (24) is matched on the threaded segment.

8. A method for preventing deflection of a shield receiving a vertical freezing hole, using the anti-deflection drilling device for a shield receiving a vertical freezing hole as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Prepare mud in the mud tank according to the formation properties and drilling requirements, and use a mud pump to transport it into the borehole; Step 2: Install the drill rod, drill bit (1) and other drilling tools on the drilling rig, and check the linearity of the drill rod; adjust the position and angle of the drilling rig to align the drilling tool with the drilling position; Step 3: Start the drilling machine, rotate the drill bit (1) slowly, and the drill bit (1) begins to contact the ground. In the initial drilling, control the drilling speed and gradually deepen the borehole; start the mud pump to pump the prepared mud into the borehole through the drill pipe; the mud circulates in the borehole, takes the rock cuttings out of the borehole through the nozzle of the drill bit (1), and keeps the borehole wall stable; Step 4: During the drilling process, continue to pump the mud and keep the mud circulating to ensure that the drill bit (1) is always adequately lubricated and cooled; maintain appropriate drilling pressure and speed during operation; Step 5: After the drilling depth reaches 5-10m, the drill rod is lifted, and an anti-deflection drilling device for receiving vertical freezing holes of the shield is installed between the drill bit (1) and the drill rod adjacent to the drill bit (1), and then drilling is continued. When the drilling is deflected, the correction block (7) on the lower correction section (6) on the high side of the deflection and the correction block (7) on the upper correction section (6) on the low side of the deflection extend out, and the anti-deflection unit (3) is straightened from two directions symmetrically about the center of the weight vertical section (5), and the anti-deflection unit (3) then drives the drill bit (1) to be straightened; Step 6: As the hole deepens, drill rods need to be added section by section. After each section is drilled, drilling is stopped, the drill tool is lifted, the next section of drill rod is connected, and drilling continues.

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