JP6475992B2 - Drilling tool - Google Patents

Description

  The present invention relates to a drilling tool that is mounted on a drilling device that drills a lining material covering an inner peripheral surface of a buried pipe such as a sewage pipe from the inside of the buried pipe and cuts the lining material.

In order to rehabilitate (repair) old pipes such as sewage pipes, an all-liner method (registered trademark) was developed in which a thermosetting synthetic resin such as FRP (fiber reinforced plastic) is lined on the inner peripheral surface of the pipe. It is used for practical use (see Patent Document 1). The procedure of the all liner method is as follows (see FIG. 6).
(1) The cylindrical body 53 containing uncured thermosetting synthetic resin is inserted into the buried pipe main pipe 20 from the manhole 21, and the cylindrical body 53 is drawn into the buried pipe main pipe 20. A supply hose 54 is inserted in the cylindrical body 53 in advance.
(2) The tubular body 53 is filled with water from the boiler car 52 parked on the ground through the supply hose 54, and the tubular body 53 is pressed against the inner peripheral surface of the buried pipe main pipe 20.
(3) In this state, the water in the cylindrical body 53 is sucked up and heated by the boiler wheel 52, and the heated water is returned again into the cylindrical body 53, and the thermosetting synthetic resin in the cylindrical body 53 is removed. Harden.
(4) Waiting for the thermosetting synthetic resin to harden, suck up the water in the cylindrical body 53, and then cut both ends of the cylindrical body 53 and collect the supply hose 54.

  A large number of branch pipes are connected to the buried pipe main pipe. Therefore, by lining the inner peripheral surface of the buried pipe main pipe, the connecting portion with the branch pipe is blocked with the lining material. Therefore, for example, in Patent Document 2, a cutting motor unit that performs a drilling operation by rotating a drilling tool having a plurality of cutting blades, a reach cylinder unit that moves the cutting motor unit in the radial direction of the buried pipe main body, and a cutting motor An existing pipe turning device is disclosed that includes an extension cylinder rod that supports the part and the reach cylinder part, and an extension cylinder that advances and retracts the extension cylinder rod in the axial direction of the buried pipe main pipe.

JP-A-6-234159 JP 2003-285221 A

  In recent years, GFRP (glass fiber reinforced plastic) has been used as a lining material in order to increase the strength of rehabilitated sewer pipes. Since these GFRP rehabilitated pipes are reinforced with glass fiber, when a conventional drilling tool is used, the cutting blade is heavily worn, and the drilling time is about five times longer than the conventional FRP rehabilitated pipe. doing. Further, in the conventional drilling tool, since the holder and the cutting blade are integrated, if even one of the four blades is damaged and worn, the drilling tool itself must be replaced with a new one.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a drilling tool capable of drilling with higher efficiency than before and capable of exchanging only damaged and worn cutting blades.

In order to achieve the above object, the present invention is mounted on a perforating apparatus for perforating a lining material made of glass fiber reinforced plastic covering the inner peripheral surface of a buried pipe from the inside of the buried pipe, and cuts the lining material. A drilling tool,
The radial direction of the buried pipe is the direction of the rotation axis, a holder that moves around the rotation axis while moving in the direction of the rotation axis, a rectangular plate, and a melting high speed that is detachably attached to the holder And a plurality of cutting blades.

A cutting blade made of cemented carbide is widely used as the cutting blade. However, as will be described later, when a drilling test of a GFRP lining was performed by attaching a cemented carbide cutting blade to a drilling tool, the drilling took nearly 4 minutes and the vibration during drilling was large. Therefore, a cutting blade made of high-speed tool steel was manufactured and a GFRP lining drilling test was conducted.
High-speed tool steel is also called high-speed steel, and is classified into powder high-speed steel and melting high-speed steel depending on the manufacturing method. In general, the powder high speed steel is tougher than the melt high speed steel, is excellent in wear resistance, and is strong in fatigue and rich in toughness. The service life of the powder high speed steel is longer than that of the melt high speed steel.
Therefore, a GFRP lining drilling test was carried out by attaching a powder high-speed cutting blade to a drilling tool. The drilling took a little over 4 minutes, and vibration during drilling was also observed. On the other hand, when a cutting test made of a GFRP lining was conducted by attaching a cutting blade made of melting high speed to a drilling tool, drilling was completed in just over 1 minute, and vibration during drilling was also small. The above test results are the knowledge obtained by the present inventors and the like, which overturns the technical common sense of those skilled in the art.

  Based on the test results, in the drilling tool according to the present invention, the cutting blade is made of melted high speed steel. In addition, in the drilling tool according to the present invention, since the cutting blade is detachably attached to the holder, only the cutting blade that has been damaged and worn can be replaced.

Further, in the drilling tool according to the present invention, the cutting blade is attached to the holder so that the long side direction of the cutting blade is the direction of the rotation axis,
The front end of the cutting blade in contact with the lining material is a cutting portion that cuts the lining material, and the rake angle in the rotation axis direction of the cutting portion is 6 ° or more and 12 ° or less. This is preferable.

When the rake angle in the direction of the rotation axis in the cutting part is less than 6 °, the drilling time is 2 minutes or more, and vibration and sound during drilling increase.
On the other hand, when the rake angle in the direction of the rotation axis in the cutting part is more than 12 °, the wedge effect becomes too great and the load applied to the drilling device becomes excessive.

Further, in the drilling tool according to the present invention, the cutting blade is attached to the holder so that the short side direction of the cutting blade is a direction perpendicular to the rotation axis,
With respect to at least two cutting blades, the long-side tip of the cutting blade located on the rotary shaft side is located farther from the rotary shaft than the long-side base end, and the long side and the rotary shaft It is preferable that the angle formed by is greater than 1 ° and less than 8 °.

If the angle formed between the long side located on the rotating shaft side and the rotating shaft is 1 ° or less, the cut disc-shaped lining material does not fall and fits in the holder (hereinafter referred to as “core clogging”). Therefore, the operator must remove the cut lining material from the holder.
On the other hand, if the angle formed between the long side located on the rotating shaft side and the rotating shaft is 8 ° or more, vibration during cutting may be large and hinder cutting.

  Further, in the drilling tool according to the present invention, it is preferable that the ridge line constituted by the rake face and the flank face in the rotational axis direction in the cutting portion is chamfered, and the width of the chamfered face is 0.3 mm or more. To do.

By chamfering the ridgeline constituted by the rake face and the flank face and setting the width of the chamfered face to 0.3 mm or more, vibration during drilling is reduced, and the drilling time can be shortened. If the width of the chamfered surface is less than 0.3 mm, the cutting blade bites into the lining material at the beginning of cutting, and vibration is generated.
The maximum width of the chamfered surface is about 2 mm.

  In the drilling tool according to the present invention, since a plurality of cutting blades are made of melted high speed steel and are detachably attached to the holder, drilling can be performed more efficiently than before, and only cutting blades that have been damaged and worn can be replaced. It is. Thereby, the efficiency of drilling work and the reduction of the cost required for drilling work can be achieved.

1 is a perspective view of a drilling device equipped with a drilling tool according to an embodiment of the present invention. It is a schematic diagram for demonstrating the drilling method of the lining material by the drilling apparatus with which the said drilling tool was mounted | worn. It is the perspective view of the drilling tool, and the enlarged view of a cutting-blade front-end | tip part. (A) is a plan view of a holder constituting the drilling tool, and (B) is an elevation view of the holder. (A) is a front view of the cutting blade constituting the drilling tool, (B) is a side view of the cutting blade, and (C) is a plan view of the cutting blade. It is a schematic diagram for demonstrating an all liner construction method.

  Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention.

FIG. 1 shows a drilling device 10 equipped with a drilling tool 11 according to an embodiment of the present invention.
The drilling device 10 includes a drilling tool 11 that cuts the lining material that covers the inner peripheral surface of the buried pipe, a rotating unit 14 that holds the drilling tool 11 and rotates the drilling tool 11, and a rotating unit 14 that holds the rotating unit 14. And a cylindrical body 16 for holding the lift 15 and moving the lift 15 in the axial direction of the buried pipe and rotating it in the circumferential direction of the buried pipe. ing. Further, wheels 18 are respectively attached to both side portions of the body portion 16, and an outrigger 17 extending in the radial direction of the buried pipe is provided on the upper portion of the body portion 16.

  A method of drilling the lining material 23 covering the buried pipe main pipe 20 from the buried pipe main pipe 20 using the drilling device 10 will be described with reference to FIG. A plurality of branch pipes 22 extending from the ground are connected to the buried pipe main pipe 20 buried in the ground, and a connecting portion between the branch pipe 22 and the buried pipe main pipe 20 is closed by a lining material 23. Yes. In addition, manholes 21 that open upward are respectively installed at both ends of the buried pipe main pipe 20.

(1) The front end of the drilling device 10 (the side on which the drilling tool 11 is mounted) and the rear end of the camera device 25 on which the camera 26 having a light source such as a light is mounted (the side on which the camera 26 is mounted) Are connected with a wire 24. The lens of the camera 26 is directed to the rear drilling device 10. For convenience, the side with the camera device 25 with respect to the punching device 10 is referred to as the “front” side, and the side with the punching device 10 with respect to the camera device 25 is referred to as the “rear” side.
(2) Wires 24 are respectively attached to the rear end portion of the punching device 10 and the front end portion of the camera device 25, and the punching device 10 and the camera device 25 are inserted into the buried pipe main pipe 20 from the manhole 21. The wire 24 attached to the rear end portion of the punching device 10 is drawn out from the manhole 21 installed behind the punching device 10 to the ground, and the wire 24 attached to the front end portion of the camera device 25 is connected to the camera device 25. It is pulled out from the manhole 21 installed in front of the ground.

(3) While confirming the position of the punching device 10 with the camera 26 mounted on the camera device 25, the wire 24 attached to the front end of the camera device 25 is pulled, and the camera device 25 and the punching device 10 are embedded Advance in tube 20. Then, when the perforating apparatus 10 reaches the connecting portion between the branch pipe 22 and the buried pipe main pipe 20, the advancement of the perforating apparatus 10 is stopped.
(4) The body portion 16 of the perforating apparatus 10 is fixed by extending the outrigger 17 equipped in the perforating apparatus 10 toward the lining material 23 and pressing the lining material 23 with the outrigger 17.

(5) The lift part 15 is moved in the axial direction of the buried pipe main pipe 20 with respect to the body part 16 and rotated in the circumferential direction of the buried pipe main pipe 20 so that the drilling tool 11 faces the branch pipe 22.
(6) While operating the rotating part 14 to rotate the drilling tool 11, the lift part 15 is operated to move the drilling tool 11 radially outward of the buried pipe main pipe 20, and a hole is made in the lining material 23.

  The overall shape of the drilling tool 11 is shown in FIG. As shown in the figure, the drilling tool 11 includes a holder 12 mounted on a rotating shaft (not shown) of the rotating unit 14 of the drilling apparatus 10 and a plurality of (in this embodiment) detachably attached to the holder 12 with bolts 19. It is comprised from the cutting blade 13 of 4 sheets in the form.

  4A and 4B show the shape of the holder 12. The holder 12 includes a base 28 having a hexagonal shape in plan view, a disk-shaped plate 27 (about 80 mm in diameter) formed on the upper surface of the base 28, and a plurality (4 in this embodiment) formed on the peripheral edge of the plate 27. ) Standing portions 29.

  The center of the plate 27 is the axis 30 of the rotating shaft, and the angle formed by the adjacent standing portion 29 and the axis 30 is 90 °. Each standing portion 29 has a partial cylindrical shape, and is formed with two bolt holes 32 into which bolts 19 for fixing the cutting blade 13 are screwed. Moreover, in order to reduce friction with the lining material during cutting, the top of the standing portion 29 is inclined downward from the side on which the cutting blade 13 is mounted toward the non-mounting side (FIG. 4B). reference).

The holder 12 moves in the direction of the rotation axis while rotating around the rotation axis with the radial direction of the buried pipe main pipe 20 as the direction of the rotation axis (axial core 30).
The rotating direction of the holder 12 is clockwise with respect to the moving direction of the drilling tool 11, that is, the direction of the right screw. Therefore, in the plan view of the holder 12 shown in FIG. 4A, the rotation direction of the holder 12 is counterclockwise.

As shown in FIGS. 5A to 5C, the cutting blade 13 has a rectangular plate shape (short side length: about 10 mm, long side length: about 30 mm, thickness: about 3 mm to 5 mm), and a plate material Bolt holes 33 through which the bolts 19 are inserted are provided at two locations in the long side direction.
The material type of the cutting blade 13 is dissolution high speed, and SKH57 etc. can be used.

  Each cutting blade 13 is fixed by a bolt 19 to one side surface of the standing portion 29 of the holder 12 (the side surface in which the holder 12 rotates). Thus, the long side direction of the cutting blade 13 is the direction of the rotation axis (axial core 30), and the short side direction of the cutting blade 13 is the direction orthogonal to the rotation axis.

A portion far from the rotation axis of the distal end portion in the long side direction of the cutting blade 13 is a cutting portion 31 that contacts the lining material and cuts the lining material. The cutting part 31 is convex toward the moving direction and the rotating direction of the drilling tool 11.
The thickness of the cutting blade 13 is such that the base end portion in the long side direction is thinner than the distal end portion in the long side direction with the cutting portion 31 (see FIG. 5B) and the short side direction side portion with the cutting portion 31 is present. In comparison, the short side direction portion without the cutting portion 31 is thin (see FIG. 5C). That is, the cutting blade 13 is thicker toward the cutting part 31.

Since the lining material is cut while the drilling tool 11 moves and rotates, the rake angle α and the relief angle γ of the cutting part 31 provided on the cutting blade 13 are orthogonal to the rotation axis direction of the drilling tool 11. Must be set for each direction.
In the present embodiment, the rake angle α _A in the rotation axis direction of the cutting part 31 is 6 ° to 12 °, and the clearance angle γ _A is 14 ° to 16 ° (see FIG. 5B). The rake angle α _{V in the} direction perpendicular to the rotation axis is set to 1 ° to 3 ° (see FIG. 5C). Further, the clearance angle γ _{V in the} direction perpendicular to the rotation axis is provided on both sides in the short side direction, and is set to 7 ° to 9 ° (see FIG. 5C).

In the present embodiment, as shown in FIG. 5A, the long-side tip P of the cutting blade 13 located on the rotary shaft side is farther from the rotary shaft than the long-side base end Q, The angle β formed by the long side and the rotation axis (hereinafter referred to as “inner long side inclination angle”) is more than 1 ° and less than 8 °.
Furthermore, as shown in the enlarged view of FIG. 3, the ridgeline constituted by the rake face 34 and the flank face 35 in the rotation axis direction in the cutting portion 31 is chamfered, and the width of the chamfered face 36 (hereinafter referred to as “margin width”). Is called 0.3 mm or more.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the configuration described in the above-described embodiment, and is within the scope of matters described in the claims. Other possible embodiments and modifications are also included. For example, in the above embodiment, the number of cutting blades is four, but may be three or five or more. Moreover, in the said embodiment, although the inner side long side inclination | tilt angle was set about all the cutting blades, what is necessary is just to set an inner side long side inclination | tilt angle about at least two cutting blades.

A verification test carried out to verify the effects of the present invention will be described.
The drilling tool was attached to a drilling device and inserted into a cylindrical GFRP having a diameter of 600 mm and a thickness of 20 mm, and a drilling test was performed. In the case of the sewage pipe, the inner diameter of the buried pipe main pipe is about 270 mm to 600 mm, and the thickness of the GFRP is about 7 mm to 20 mm.

  The drilling test was evaluated based on the drilling time and vibration during drilling. Specifically, when the perforation time was 2 minutes or less, the overall evaluation was ◯, when it was more than 2 minutes and 3 minutes or less, when the overall evaluation was Δ, and when it was more than 3 minutes, the overall evaluation was x. At that time, if the vibration and / or sound at the time of drilling is small, the rank is raised (for example, →→ ◎), and if the vibration and sound at the time of drilling is large, the rank is lowered by one (for example, ◯ → Δ).

Table 1 shows the results of the first test conducted on the influence of the grade of the cutting blade on the drilling operation.
The melting high speed used in Example 1 is SKH57, the cemented carbide used in Comparative Example 1 is K20, and the powder high speed used in Comparative Example 2 is HAP10.
For all specimens, the rake angle in the direction of the rotation axis of the cutting blade was 10 °, the clearance angle was 15 °, the rake angle in the direction perpendicular to the rotation axis was 2 °, and the clearance angle was 8 °. Moreover, about all the test bodies, the inner long side inclination | tilt angle was 0 degree and the margin width | variety was 0 mm.

  In Example 1, since the perforation time was 2 minutes or less and the vibration during perforation was small, the overall evaluation was evaluated as “◎”. On the other hand, in Comparative Examples 1 and 2, since the perforation time exceeded 3 minutes and the vibration was large, the overall evaluation was x.

In addition, Table 2 shows the results of the second test conducted with the cutting blade material grade as melting high-speed SKH57 regarding the effects of the rake angle in the rotation axis direction of the cutting blade, the inner long side inclination angle, and the margin width on the drilling operation. Show.
In addition, in the comprehensive evaluation of the drilling test in the second test, the core clogging was considered in addition to the above-described evaluation method.

The second test revealed the following.
When the rake angle in the direction of the rotation axis of the cutting blade is 6 ° or more and 12 ° or less, the cutting time is 2 minutes or less (Examples 2 to 6). In particular, in Examples 4 and 5, vibration during cutting was small, and no core clogging occurred. On the other hand, when the rake angle in the direction of the rotation axis of the cutting blade is less than 6 °, the cutting time becomes more than 2 minutes (see Example 7).
When the inner long side inclination angle is 1 ° or less, core clogging occurs (Examples 2 and 3).
When the margin width is less than 0.3 mm, the cutting blade bites into the lining material at the beginning of cutting, and vibration is generated (Example 2).

10: Drilling device, 11: Drilling tool, 12: Holder, 13: Cutting blade, 14: Rotating part, 15: Lifting part, 16: Body part, 17: Outrigger, 18: Wheel, 19: Bolt, 20: Embedded pipe Main pipe, 21: manhole, 22: branch pipe, 23: lining material, 24: wire, 25: camera device, 26: camera, 27: plate, 28: base, 29: standing part, 30: shaft core, 31 : Cutting part, 32, 33: bolt hole, 34: rake face, 35: flank face, 36: chamfered face

Claims (4)

A drilling tool that is attached to a drilling device that drills a lining material made of glass fiber reinforced plastic covering the inner peripheral surface of the buried pipe from the inside of the buried pipe, and cuts the lining material,
The radial direction of the buried pipe is the direction of the rotation axis, a holder that moves around the rotation axis while moving in the direction of the rotation axis, a rectangular plate, and a melting high speed that is detachably attached to the holder A drilling tool comprising a plurality of cutting blades. The drilling tool according to claim 1, wherein the cutting blade is attached to the holder so that a long side direction of the cutting blade is a direction of the rotation axis,
The front end of the cutting blade in contact with the lining material is a cutting portion that cuts the lining material, and the rake angle in the rotation axis direction of the cutting portion is 6 ° or more and 12 ° or less. A drilling tool characterized by that. The drilling tool according to claim 2, wherein the cutting blade is attached to the holder so that a short side direction of the cutting blade is a direction orthogonal to the rotation axis,
With respect to at least two cutting blades, the long-side tip of the cutting blade located on the rotary shaft side is located farther from the rotary shaft than the long-side base end, and the long side and the rotary shaft A drilling tool characterized in that the angle formed by is more than 1 ° and less than 8 °.   4. The drilling tool according to claim 2, wherein a ridge line constituted by the rake face and the flank face in the direction of the rotation axis in the cutting portion is chamfered, and the width of the chamfered face is 0.3 mm or more. Drilling tool.

Images