Blowout preventer for downward drilling

Abstract

The utility model discloses a downward drilling blowout preventer, which relates to the field of underground coal mine drilling and comprises a blowout preventer body, an orifice pipe, a driving mechanism, a clamping pad, an extraction port and a slag discharge port. A blowout prevention cavity is formed in the blowout prevention device body, and a drill rod channel communicated with the blowout prevention cavity penetrates through the blowout prevention device body. An orifice pipe is mounted at the lower end of the drill rod channel; driving mechanisms are symmetrically arranged on the two sides of the upper end of the drill rod channel, and the driving ends of the driving mechanisms are connected with plugging blocks located in the drill rod channel. The blowout prevention device body is provided with an extraction opening and a slag discharging opening, and the extraction opening and the slag discharging opening are both communicated with the blowout prevention cavity. The device has the advantages that when gas is abnormal, the drill rod stops drilling, the driving mechanism drives the two plugging blocks to clamp the two sides of the drill rod, a drill rod channel can be plugged, and potential safety hazards are eliminated.

Description

Technical Field

[0001] The utility model relates to the field of underground drilling in coal mines, in particular to a downward drilling blowout prevention device. Background Art

[0002] Downward through-layer drilling construction is a gas control method for coal tunnel excavation and coal uncovering for cover. The construction space of the downward hole is small, and the automatic gas classification and control device with a large mechanical structure cannot be installed. At present, a simple flap blowout prevention device is generally used. This blowout prevention device is small in size, simple in structure, and easy to install. It is suitable for downward through-layer holes with narrow construction space. However, when gas abnormalities occur, the existing flap blowout prevention device cannot block the drill rod channel, which is easy to cause gas over-limit accidents and poses certain safety hazards; and there are problems with drainage and slag discharge, and the drill cuttings and slag cannot be discharged smoothly. Utility Model Content

[0003] The technical problem to be solved by the utility model is that the drilling rod channel can be blocked when the gas is abnormal.

[0004] The utility model achieves the solution to the above technical problems through the following technical means: a downward drilling blowout prevention device, including a blowout prevention device body, an orifice pipe, a driving mechanism, a clamping pad, an extraction port and a slag discharge port; a blowout prevention cavity is provided inside the blowout prevention device body, and a drill rod channel connected to the blowout prevention cavity is penetrated through the blowout prevention device body; an orifice pipe is installed at the lower end of the drill rod channel; a driving mechanism is symmetrically provided on both sides of the upper end of the drill rod channel, and the driving end of the driving mechanism is connected to a blocking block located in the drill rod channel; an extraction port and a slag discharge port are provided on the blowout prevention device body, and the extraction port and the slag discharge port are both connected to the blowout prevention cavity. When the gas is abnormal, the drill rod stops drilling, and the driving mechanism drives the two blocking blocks to clamp the two sides of the drill rod, so as to block the drill rod channel and eliminate safety hazards.

[0005] As an optimized technical solution, a methane sensor is also provided on the blowout prevention device body.

[0006] As an optimized technical solution, the central axis of the drill rod channel is located below the central axis of the blowout prevention device body. Lowering the center of the drill rod channel can prevent the drill cuttings from returning from the bottom of the hole from accumulating in the blowout prevention cavity. On the one hand, the slag discharge is smoother, and on the other hand, the space of the blowout prevention cavity above the drill rod is increased, which can buffer more gas and prevent excessive drill cuttings from being sucked in during negative pressure extraction.

[0007] As an optimized technical solution, a clamping ring joint is provided at the lower end of the drill pipe channel, and an annular pipe hoop is provided at the upper end of the orifice pipe and is fixedly connected to the clamping ring joint through the annular pipe hoop. The vulnerable orifice pipe parts are easy to replace, and the orifice pipe can be replaced separately after being worn, which saves costs and increases the service life of the blowout preventer.

[0008] As an optimized technical solution, the slag discharge port is arranged at a position on the lower side of the blowout prevention device body facing the coal and rock layer. The slag discharge port is downward, so that the drill cuttings and slag can be discharged smoothly.

[0009] As an optimized technical solution, the extraction port is arranged on the upper side of the blowout prevention device body and is arranged obliquely upward, so as to facilitate the installation and arrangement of the extraction pipeline.

[0010] As an optimized technical solution, two extraction ports are provided.

[0011] As an optimized technical solution, the driving mechanism adopts an oil cylinder.

[0012] As an optimized technical solution, the blocking block adopts a rubber pad.

[0013] As an optimized technical solution, the main body of the blowout prevention device is made of stainless steel.

[0014] The advantages of the utility model are:

[0015] 1. When the gas is abnormal, the drill rod stops drilling, and the driving mechanism drives the two blocking blocks to clamp the two sides of the drill rod, which can block the drill rod channel and eliminate safety hazards.

[0016] 2. Lowering the center of the drill pipe channel can prevent the drill cuttings from returning from the bottom of the hole from accumulating in the blowout prevention chamber. On the one hand, the slag discharge is smoother, and on the other hand, the space of the blowout prevention chamber above the drill pipe is increased, which can buffer more gas and prevent excessive drill cuttings from being sucked in during negative pressure extraction.

[0017] 3. The slag discharge port is facing downward, so the drill cuttings and slag can be discharged smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of a downward drilling blowout prevention device according to an embodiment of the utility model. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described in combination with the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the utility model.

[0020] like Figure 1As shown, an embodiment of the utility model discloses a downward drilling blowout prevention device, including a blowout prevention device body 1, an orifice pipe 2, a driving mechanism 3, a clamping pad (not shown), a methane sensor (not shown), a extraction port 4 and a slag discharge port 5.

[0021] The blowout preventer body 1 is made of stainless steel, a blowout preventer cavity is arranged inside the blowout preventer body 1, and a drill rod channel connected to the blowout preventer cavity runs through the blowout preventer body 1; the central axis of the drill rod channel is located 100 mm below the central axis of the blowout preventer body 1, and lowering the center of the drill rod channel can prevent the drill cuttings returning from the bottom of the hole from accumulating in the blowout preventer cavity. On the one hand, the slag discharge is smoother, and on the other hand, the space of the blowout preventer cavity above the drill rod is increased, which can buffer more gas, and it is not easy to suck in too much drill cuttings during negative pressure extraction.

[0022] A clamping ring joint is welded at the lower end of the drill rod channel, and an annular pipe hoop is welded at the upper end of the orifice pipe 2 and is fixedly connected to the clamping ring joint through the annular pipe hoop. The orifice pipe 2 is used to reinforce the borehole and install the blowout prevention device body 1. The drill rod 6 passes through the drill rod channel and the orifice pipe 2 in sequence and then enters the coal rock layer 7.

[0023] Driving mechanisms 3 are symmetrically arranged on both sides of the upper end of the drill rod channel, and the driving ends of the driving mechanisms 3 are connected to the blocking blocks located in the drill rod channel. The driving mechanism 3 adopts an oil cylinder, and the blocking blocks adopt a rubber pad.

[0024] A methane sensor is provided on the main body 1 of the blowout prevention device, and the driving mechanism 3, the methane sensor and the drilling rig are all connected to the PLC electronic control box. When the methane sensor detects gas abnormality, the PLC electronic control box first cuts off the power supply of the drilling rig to stop the drill rod 6 from drilling, and then controls the two driving mechanisms 3 to drive the blocking blocks to clamp the two sides of the drill rod 6 to block the drill rod channel.

[0025] Two 2-inch extraction ports 4 are arranged on the upper side of the blowout prevention device body 1, and the extraction ports 4 are connected to the blowout prevention cavity; the extraction ports 4 are arranged upwardly and tilted to facilitate the installation and arrangement of the extraction pipeline.

[0026] A slag discharge port 5 is arranged on the lower side of the blowout prevention device body 1 facing the coal rock layer 7, and the slag discharge port 5 is connected to the blowout prevention cavity; the slag discharge port 5 is arranged to be inclined downward, and the drill cuttings and drill slag returned from the hole can be smoothly discharged out of the blowout prevention device body 1.

[0027] Working principle: first, after drilling a hole in the coal rock layer 7, fix the orifice pipe 2, and fix the blowout prevention device body 1 to the orifice pipe 2. At this time, the drill rod channel and the slag discharge port 5 are open to facilitate slag discharge; then install the methane sensor to detect the initial methane amount; then the drill rod 6 passes through the drill rod channel and the orifice pipe 2 in turn and enters the coal rock layer 7, and the PLC electrical control box controls the start of the drilling rig to ensure the fluid supply pressure and fluid supply speed, so that drilling work can be carried out; when the methane sensor detects gas abnormality, the PLC electrical control box first cuts off the power supply of the drilling rig to stop the drill rod 6 from drilling, and then controls the driving mechanism to drive the two blocking blocks to clamp the two sides of the drill rod 6 to block the drill rod channel.

[0028] 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 aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A downward drilling blowout prevention device, characterized in that: The blowout preventer comprises a blowout preventer body, an orifice pipe, a driving mechanism, a clamping pad, an extraction port and a slag discharge port; a blowout preventer cavity is arranged inside the blowout preventer body, and a drill rod channel connected to the blowout preventer cavity is penetrated through the blowout preventer body; an orifice pipe is installed at the lower end of the drill rod channel; driving mechanisms are symmetrically arranged on both sides of the upper end of the drill rod channel, and the driving end of the driving mechanism is connected to a blocking block located in the drill rod channel; an extraction port and a slag discharge port are arranged on the blowout preventer body, and both the extraction port and the slag discharge port are connected to the blowout preventer cavity.

2. The downward drilling blowout prevention device according to claim 1, characterized in that: A methane sensor is also provided on the blowout prevention device body.

3. The downward drilling blowout prevention device according to claim 1, characterized in that: The central axis of the drill rod channel is located below the central axis of the blowout prevention device body.

4. The downward drilling blowout prevention device according to claim 1, characterized in that: A clamping ring joint is arranged at the lower end of the drill pipe passage, and an annular pipe hoop is arranged at the upper end of the orifice pipe and is fixedly connected to the clamping ring joint through the annular pipe hoop.

5. The downward drilling blowout prevention device according to claim 1, characterized in that: The slag discharge port is arranged at a position on the lower side of the blowout prevention device body facing the coal rock layer.

6. The downward drilling blowout prevention device according to claim 1, characterized in that: The extraction port is arranged on the upper side of the blowout prevention device body and is arranged obliquely upward.

7. The downward drilling blowout prevention device according to claim 1, characterized in that: The extraction ports are provided with two.

8. The downward drilling blowout prevention device according to claim 1, characterized in that: The driving mechanism adopts an oil cylinder.

9. The downward drilling blowout prevention device according to claim 1, characterized in that: The blocking block adopts a rubber pad.

10. The downward drilling blowout prevention device according to claim 1, characterized in that: The main body of the blowout prevention device is made of stainless steel.

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