JPH076343B2 - Soft rock drilling device and drilling method using the same - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

TECHNICAL FIELD The present invention relates to an apparatus used for boring various holes such as a gunpowder loading hole, a lock bolt hole, or an anchor bolt hole in a soft rock using a rock drilling machine and a boring method thereof.

[Prior art and problems]

Generally, in drilling work with a rock drill, when water is used to discharge the dust and to prevent the generation of dust, the amount of water used is 30 to 60 liters per minute (water pressure of about 3 kg / cm ² )
However, this large amount of water can be used only for rocks that have few cracks and do not become sludge by water. When drilling the above-mentioned various holes in soft rock, compressed fluid such as compressed air, water, or a mixture of these is used to discharge the dust, depending on the specific properties of the soft rock. Sometimes the wall is not self-supporting, and the perforation method using a large amount of water has many drawbacks. An object of the present invention is to eliminate the above-mentioned drawbacks by discharging the dust in the drilling of soft rock and simultaneously protecting and stabilizing the pore wall.

[Means for Solving the Problems]

The structure of the soft rock drilling device of the present invention is as follows. The hole wall stabilizing liquid supply device b is connected to the air supply pipe 2 connected to the swivel joint 3 of the rock drilling machine a. A bit c including a bit head portion 9, a body portion 10 and a joint portion 11 is screwed onto the tip of the rod 8 of the rock drilling machine a. The bit head 9 has a relatively short length from the front end surface to the vicinity of the embedded bottom of the chip 12, has a relatively deep and wide head recess 13 on the outer periphery, and ejects into the head recess 13. It has a hole 9 '. The outer peripheral surface of the body portion 10 has a diameter smaller than that of the bit head portion 9. The joint portion 11 has an axial length shorter than that of the bit head portion 9 and an outer diameter smaller than the outer diameter of the bit head portion 9 but larger than the outer diameter of the body portion 10 and has an outer peripheral surface. Relatively shallow and wide joint recesses 14 and lands 15 are alternately formed. The soft rock piercing method of the present invention has a structure in which compressed air mixed with hole wall stabilizing liquid is ejected from the ejection hole 9'of the apparatus having the above-mentioned structure, and a reconstituted powder is mixed with the hole wall stabilizing liquid mixed compressed air. Is applied to the pore walls, and the excess mixed suspension is perforated while being discharged to the outside of the pores by the action of the compressed air mixed with the stable pore wall stabilizing liquid. The pore wall stabilizing liquid preferably has viscosity or chemical properties that stabilize soft rock such as bentonite solution.

[Action]

Porosity wall stabilizing liquid having a viscosity or chemical property that stabilizes soft rock such as bentonite solution. By mixing the mixed suspension formed by mixing starch with compressed air into the pore wall, the properties of the soft rock can be determined. In spite of this, it is possible to efficiently perforate while protecting and stabilizing the pore wall, and the excess mixed suspension containing starch powder discharged to the outside of the pore does not generate dust due to the action of the pore wall stabilizing liquid. Since it is not necessary to use a large amount of water as in the conventional case, the peripheral roadbed is also less softened, and the environment and the equipment used are not adversely affected.

【Example】

The illustrated embodiment will be described in detail below. a is a rock drilling machine, 1 is a compressed air supply source such as a compressor prepared for various work machines at the construction site, and a tip of an air supply pipe 2 whose base end is connected to the compressed air supply source 1 is , Connected to the swivel joint 3 of the rock drill a. Reference numeral 4 is another compressed air supply source having a pressure slightly higher than that of the compressed air supply source 1 and is connected to one side branch receiving port 6 of an inlet pipe 5 whose tip is connected to an air outlet pipe 2 through a discharge port. . Reference numeral b denotes a hole wall stabilizing liquid supply device, which is connected to the other side branch receiving port 7 of the feed pipe 5 by piping. c is a bit screwed and fixed to the tip of the rod 8 of the rock drill a, and its configuration is as follows. The bit c is composed of a bit head portion 9, a body portion 10 and a joint portion 11, and its axial length is the same as that of a conventionally known bit. The bit head 9 has a relatively short length from the front end surface to the vicinity of the embedded bottom of the chip 12, has a relatively deep and wide head recess 13 on the outer periphery thereof, and has a jet hole 9 '. I wore it. The body portion 10 has a thread 10 'for connection on the inner peripheral surface thereof, and the outer peripheral surface thereof has a diameter smaller than that of the bit head 9. The joint portion 11 has an axial length shorter than that of the bit head portion 9 and an outer diameter smaller than that of the bit head portion 9 but larger than that of the body portion 10 and an outer periphery thereof. A relatively shallow and wide joint recess 14 and a land 15 are alternately formed on the surface. The perforation is performed by the perforation device having the above configuration as follows. Compressed air sent from the compressed air supply source 1
It is ejected from the ejection hole 9 ′ of the bit c through the swivel joint 3 and the rod 8. At this time, at the same time, the hole wall stabilizing liquid from the hole wall stabilizing liquid supply device b and the compressed air supply source 4 are ejected. The compressed air is mixed into the air supply pipe 5 and is then pressed into the air supply pipe 2. As the pore wall stabilizing liquid, for example, a known thickener solution, bentonite solution or the like having a viscosity or a chemical property that stabilizes soft rock is used. Therefore, since the hole wall stabilizing liquid is mixed in the compressed air ejected from the ejection hole 9 ′, the bit c is the soft rock 16 concerned.
When boring a desired hole 17 such as an explosive loading hole in the powder, the powdered powder is mixed with the compressed air mixed with the hole wall stabilizing liquid to form a mixed suspension 18.
Is made, it is painted on the hole wall of the hole 17 and cracks there
If there is, it goes into it, protects and stabilizes the pore walls, and the extra mixed suspension that could not be filled 18
Is discharged to the outside of the hole 17 by the action of the compressed air mixed with the stabilizing liquid for the subsequent hole wall. The bit c described above shortens the bit head 9 in the axial direction,
Since 13 is made deep and wide, the above-mentioned mixed suspension 18 containing starch powder is not easily taken into the head recess 13 thereof and wraps around the outer peripheral surface of the bit head 9, and There is no fear that the mixed suspension 18 will come into close contact with the outer peripheral surface of the bit head 9 to increase the rotation resistance. Since the body portion 10 has a small diameter, there is little resistance to the flow of the mixed suspension 18 toward the joint portion 11 in this portion,
Therefore, the flow is smoothly performed. Since the outer diameter of the joint portion 11 is made larger than the outer diameter of the body portion 10, the mixed suspension 18 in this portion slows down its flow velocity, which causes the land portion 15 to rotate due to the rotation of the bit c itself.
By applying the mixed suspension 18 to the pore wall by the action of, the pore wall is protected and stabilized to prevent collapse. The outer diameter of the joint portion 11 is larger than the outer diameter of the body portion 10 but smaller than the outer diameter of the bit head portion 9, and the axial length of the joint portion 11 is shorter than that of the bit head portion 9 and the outer circumference thereof is By forming the relatively shallow but wide joint recess 14 on the surface, it is possible to surely avoid an increase in rotational resistance due to coating the mixed suspension 18 on the hole wall, and the joint. The recessed portion 14 contributes to smooth flow and discharge of the excess mixed suspension 18 which could not be applied to the wall of the hole to the outside of the hole 17. In the above embodiment, the compressed air supply source 4 for supplying the compressed air to the feed pipe 5 is installed separately from the compressed air supply source 1, but the compressed air supply source 1 may be shared. In that case, a required high pressure is obtained by installing a required pressure adjusting device in the pipe connecting the compressed air supply source 1 and the inlet pipe 5, or alternatively, the air supply pipe 2 and the inlet pipe 5 are connected to each other. It may be connected via the required air ejector.

【The invention's effect】

As is clear from the above description, according to the device of the present invention, the above-mentioned mixed suspension containing starch powder is not easily taken into the recessed portion of the head and wraps around the outer peripheral surface of the bit head. Since the mixed suspension does not adhere to the outer peripheral surface of the bit head to increase the rotation resistance, and the joint portion has a small diameter, the mixed suspension in this portion The mixed suspension is effectively applied to the hole wall by the action of the land portion caused by the slowing of the flow velocity of the bit and the rotation of the bit itself, and also by the action of the recess of the joint portion. It is possible to reliably avoid an increase in rotational resistance due to the application of turbidity to the hole walls, and the joint recesses allow excess mixed suspension that could not be applied to the hole walls to the outside of the holes. It smoothly discharges the fluid. According to the present invention, firstly, a mixed suspension formed by mixing starch with a pore wall stabilizing liquid mixed with compressed air having a viscosity or a chemical property that stabilizes soft rock such as bentonite solution is applied to the pore wall. By doing so, it is possible to efficiently pierce the pore wall while protecting and stabilizing the pore wall regardless of the properties of the soft rock, and secondly, the excess mixed suspension containing the starch powder is discharged out of the pore. There is no danger of generating dust due to the action of the hole wall stabilizing liquid, and thirdly, there is no need to use a large amount of water as in the past, so there is less softening of the surrounding roadbed, and the environment and use It does not affect the equipment.

[Brief description of drawings]

The drawings are for explaining the embodiments of the present invention. FIG. 1 is a schematic side view of the device of the present invention, FIG. 2 is a sectional view of an essential part in a perforated state, FIG. 3 is a longitudinal sectional view of the perforated, 4 to 6 are a partial vertical sectional view, a front view and a rear view of the bit, respectively. a ... rock drill, c ... bit, 1 ... compressed air supply source,
2 ... air pipe, 3 ... swivel joint, 8 ... rod, 9 ... bit head, 9 '... spout hole, 10 ... body,
11 …… Joint part, 12 …… Chip, 13 …… Head recess, 14 ……
Joint recess, 15 …… Land, 17 …… Hole, 18 …… Mixed suspension.

Claims (3)

[Claims] 1. A hole wall stabilizing liquid supply device is connected to an air supply pipe connected to a swivel joint of a rock drill, and a rod head of the rock drill comprises a bit head, a body and a joint. The bit head has a relatively short length from the front end face to the vicinity of the embedded bottom of the chip, has a relatively deep and wide head recess on the outer periphery, and ejects into the head recess. A hole is drilled, the outer diameter of the body is smaller than that of the bit head, and the joint has an axial length shorter than that of the bit head and an outer diameter of the bit head. A soft rock drilling hole which is smaller than the diameter but larger than the outer diameter of the body and is screwed with a bit in which an outer peripheral surface of which is relatively shallow and wide and which has recesses and lands are alternately formed. apparatus. 2. A hole wall stabilizing liquid supply device is connected to an air supply pipe connected to a swivel joint of a rock drill, and the tip of the rod of the rock drill comprises a bit head, a body and a joint. The bit head has a relatively short length from the front end face to the vicinity of the embedded bottom of the chip, has a relatively deep and wide head recess on the outer periphery, and ejects into the head recess. A hole is drilled, the outer diameter of the body is smaller than that of the bit head, and the joint has an axial length shorter than that of the bit head and an outer diameter of the bit head. Use a soft rock drilling device that is smaller than the diameter but larger than the outer diameter of the body and that has a relatively shallow and wide joint recess and land alternately formed on its outer peripheral surface. Then, the compressed air mixed with the hole wall stabilizing liquid is ejected from the ejection hole of the above bit. , The mixed suspension formed by mixing the powder with the compressed air mixed with the stable liquid containing the hole wall is applied to the hole wall, and the excess mixed suspension is removed from the hole by the action of the compressed air mixed with the stable liquid containing the stable hole wall. A method for piercing soft rock, which comprises piercing while discharging into a soft rock. 3. The method for piercing soft rock according to claim 2, wherein the pore wall stabilizing liquid has a viscosity or a chemical property for stabilizing soft rock such as bentonite solution.