CN106593297A - Straight hole drilling method for drilling machine - Google Patents

Abstract

The invention provides a method for drilling straight holes with a drilling rig, which is suitable for underground drainage drilling in coal mines. Stand the drill bit on a section of round drill pipe and start drilling. After drilling the distance of one section of drill pipe, connect a section of threaded drill pipe with the same outer diameter as the drill bit, and continue drilling until the thread The drill pipe enters the borehole, connects the ordinary circular drill pipe, and drills into the borehole to reach the designated position according to the general method. The method has the advantages of straight drilling trajectory, simple operation and effective slag discharge, and can effectively solve the deviation of the drill hole from the predetermined trajectory caused by uneven force on the drill bit. At the same time, the threaded drill pipe is easy to purchase, cheap, and low drilling cost.

Description

Drilling method for drilling straight holes

technical field

The invention relates to a method for drilling straight holes with a drilling rig, and is especially suitable for long-distance drilling in areas with uneven hardness and softness of surrounding rocks.

Background technique

Drainage is the fundamental way to solve the problem of coal mine gas. The position of the drainage borehole has a great influence on the efficiency of gas extraction. The drainage effect of the coal mine gas drainage borehole in my country is very poor, which reflects the actual position of the borehole and the design position. The problem of large deviations. At present, the main method of drilling is single-type drill pipe drilling. The drill pipe is mainly round. In this method, there is a certain gap between the drill pipe and the hole wall. When the drilling distance is long, due to the uneven force on the drill bit , the drill pipe begins to bend and deviate from the direction of the drilling axis, and it is difficult for the drill hole to reach the designated position.

Contents of the invention

Technical problem: The object of the present invention is to overcome the deficiencies in the prior art and provide a low-cost drilling method that can effectively prevent the drill pipe from drifting during the drilling process.

Technical solution: The drilling rig drilling method of the present invention comprises the following steps:

The method for drilling straight holes with a drilling rig uses a drill bit and a drill rod to drill, and the drill rod includes a circular drill rod and a threaded drill rod, comprising the following steps:

a. Select a round drill pipe as the first section of drill pipe, install the drill bit on the head of the first section of drill pipe, connect the tail of the first section of drill pipe with the drilling rig through the connecting piece, and start drilling;

b. When the first section of drill pipe is drilled into the drill hole, stop drilling, separate the drilling machine from the tail of the first section of drill pipe, and connect a section of threaded drill pipe through the connecting piece as the second section of drill pipe. Continue drilling after the drilling rig is connected with the threaded drill pipe;

c. When the threaded drill pipe is drilled into the drill hole, stop drilling, separate the drilling machine from the threaded drill pipe, and continue to connect a section of round drill pipe with the connecting piece to continue drilling;

d. Continue to drill the drill hole according to the conventional drilling method, use the connecting piece and the round drill rod to extend the drill rod until the drill hole reaches the designated position, and complete the drilling.

The threaded drill pipe has the same inner diameter as the ordinary round drill pipe, and is fastened through internal threads or connecting pieces with connecting threads at both ends. The outer diameter of the threaded drill pipe is the same as that of the drill bit, and the outer diameter of the two is larger than that of the round drill pipe. The threaded drill rod is composed of a hollow cylinder and an external thread, and is made of high-strength steel with high bending strength, which can effectively prevent the drill bit from bending when the force is uneven. The thread on the threaded drill rod is an ordinary threaded rod thread or a large helical thread, and the thread height of the large helical thread is 10mm-30mm, which can effectively improve the stability of drilling when drilling into a rock wall with a brittle structure.

Beneficial effects: the present invention effectively prevents the deviation of the drill rod during the drilling process and the deviation of the drilled hole from the designed position by connecting a threaded drill rod between the first round drill rod and the subsequent round drill rod. When starting to drill, determine the drilling angle and start drilling. The drill bit enters the surrounding rock (coal body), and the drill pipe also enters the surrounding rock (coal body). Direction OK. Since the second drill rod is a threaded drill rod, its outer diameter is the same as that of the drill bit, so the gap between the inner wall of the borehole and it is very small, which effectively limits the swing of the first two drill rods. When the drill bit is subjected to uneven force, the drill pipe will tend to deflect in the direction of the small force. At this time, because the gap between the drill pipe and the wall of the hole is small, the wall of the hole can effectively give the reaction force to the drill pipe, resulting in the failure of the drill pipe. Swing and deflection prevent the drilling direction of the drill bit from shifting. In addition, when the drilling distance is very long, due to the large number of drill pipes, it is inevitable that the drill pipes will shake and deviate. The swing of the drill rod behind cannot affect the drilling direction. At the same time, a large amount of drill cuttings will be discharged from the drill bit. The first section of the drill pipe adopts an ordinary round drill pipe, and the resistance of the drill cuttings is small when the gap between it and the hole wall is large. When the drill cuttings reach the second section of the drill pipe, the drill The flow rate of chips is greatly reduced, and the thread of the threaded drill pipe can effectively discharge slag at this time. If all threaded drill pipes are used, the drilling resistance will be very large, and only the second drill pipe adopts threaded drill pipes, which effectively controls the drilling resistance.

Description of drawings

Fig. 1 is the drill pipe drill bit connection schematic diagram of the present invention;

In the figure: 1-drilling surrounding rock, 2-drilling rod, 3-threaded drilling rod, 4-drilling hole, 5-circular drilling rod, 6-drilling bit.

detailed description

An embodiment of the present invention will be further described below in conjunction with accompanying drawing:

As shown in Figure 1, the drill rig of the present invention drills the straight hole drilling method, utilizes drill bit 6 and drill rod 2 to drill, and described drill rod 2 comprises circular drill rod 5 and threaded drill rod 3, and threaded drill rod 3 and Ordinary circular drill pipe 2 and drill pipe 5 have the same inner diameter, and are connected and fastened by internal threads or connecting pieces with connecting threads at both ends. 5 large.

The threaded drill rod 3 is composed of a hollow cylinder and an external thread, and is made of high-strength steel with high bending strength, which can effectively prevent the drill bit from bending when the force is uneven. The thread on the threaded drill rod 3 is an ordinary threaded rod thread or a large helical thread, and the thread height of the large helical thread is 10mm-30mm, which can effectively improve the stability of drilling when drilling into a rock wall with a brittle structure.

Including the following steps:

a. Select a section of round drill pipe 5 as the first section of drill pipe, install a drill bit 6 on the head of the first section of drill pipe, connect the tail of the first section of drill pipe with the drilling machine through a connecting piece, and start drilling;

b. When the first section of drill pipe is drilled into the drill hole 4, stop drilling, separate the drilling machine from the tail of the first section of drill pipe, and connect a section of threaded drill pipe 3 through the connecting piece as the second section of drill pipe , continue drilling after the drilling machine is connected with the threaded drill rod 3;

c. When the threaded drill rod 3 is drilled into the drill hole 4, stop drilling, separate the drilling machine from the threaded drill rod 3, and continue to connect a section of the circular drill rod 2 with a connector to continue drilling;

d. Continue to drill into the borehole 4 according to the conventional drilling method, use the connector and the circular drill pipe 5 to extend the drill pipe until the drill hole reaches the designated position, and complete the drilling.

Claims (5)

1. A drilling method for drilling straight holes, using a drill bit (6) and a drill rod (2) to drill, and the drill rod (2) includes a circular drill rod (5) and a threaded drill rod (3), It is characterized in that comprising the steps of: a. Select a round drill pipe (5) as the first section of drill pipe, install the drill bit (6) on the head of the first section of drill pipe, connect the end of the first section of drill pipe with the drilling machine through a connecting piece, and start to drill; b. When the first section of drill pipe is drilled into the drill hole (4), stop drilling, separate the drilling machine from the end of the first section of drill pipe, and connect a section of threaded drill pipe (3) through the connecting piece as the second section Two-section drill pipe, connect the drilling rig to the threaded drill pipe (3) and continue drilling; c. When the threaded drill pipe (3) is drilled into the drill hole (4), stop drilling, separate the drilling machine from the threaded drill pipe (3), and continue to connect a round drill pipe (2) with the connecting piece ), continue to drill; d. Continue to drill the drill hole (4) according to the conventional drilling method, use the connecting piece and the round drill rod (5) to extend the drill rod until the drill hole reaches the designated position, and complete the drilling. 2. The drilling method for drilling straight holes according to claim 1, characterized in that: the inner diameter of the threaded drill rod (3) is the same as that of the ordinary round drill rod (2) and the drill rod (5). The end is provided with the connecting piece of connecting thread for fastening. 3. The drilling method according to claim 1, characterized in that: the outer diameter of the threaded drill rod (3) is the same as that of the drill bit (6), and the outer diameter of the two is larger than that of the circular drill rod (5). 4. The method for drilling straight holes with a drilling rig according to claim 1, characterized in that: the threaded drill rod (3) is composed of a hollow cylinder and an external thread, and is made of high-strength steel with high bending strength and effective Prevents the bit from bending when uneven force is applied to the drill. 5. The drilling method according to claim 1, characterized in that: the thread on the threaded drill rod (3) is an ordinary threaded rod thread or a large helical thread, and the thread teeth of the large helical thread The height is 10mm-30mm. When drilling into the rock wall, the structure is brittle, which can effectively improve the stability of drilling.