Ultrahigh pressure power head device for coal mine gas drainage drilling

Abstract

The invention belongs to the field of mechanical design, relates to an ultrahigh-pressure power head device for coal mine gas drainage drilling, and is particularly applied to a coal mine drilling machine. A traditional gas drainage drilling machine has the problems of leakage and damage when conveying ultrahigh-pressure water for hydraulic slotting, and gas drainage efficiency is limited. According to the invention, a novel connecting and sealing structure is adopted and comprises conical surface matching and end surface sealing of the water braid and the connecting rod, conical thread connection of the connecting rod and the driving drill rod and double-sealing-ring sealing, and an axial compensation spring is arranged, so that ultrahigh-pressure water up to 100MPa can be transmitted in the power head. According to the device, the problems in the prior art are solved, the gas drainage efficiency, the drilling operation continuity and the mine safety are improved, and meanwhile environmental protection and sustainable development are facilitated.

Description

Technical Field

[0001] The present invention belongs to the field of mechanical design and relates to a super high-pressure power head device for coal mine gas drainage boreholes. Background Art

[0002] In the process of coal mine exploitation and utilization, gas drainage is an important measure to ensure mine safety and improve exploitation efficiency. Traditional gas drainage methods mainly rely on drilling techniques of drilling rigs. Among them, the power head, as a key component of the drilling rig, plays a crucial role in driving the drill pipe to rotate and drilling into the coal seam.

[0003] In a conventional drilling rig structure, the water swivel at the tail of the power head is used to convey water into the borehole. This water passes through the hollow main shaft and the hollow active drill pipe inside the power head, and finally is transmitted to the external drill pipe and enters the borehole interior. This process not only helps to cool the drill bit and the drill pipe, but also can effectively carry and discharge the coal slag and rock cuttings generated during the drilling process, ensuring the smooth progress of the drilling operation. However, although this traditional drilling slag discharge method has been widely used in coal mine exploitation, with the continuous progress of coal mine exploitation technology and the increasing requirements for gas drainage, its limitations have become increasingly prominent.

[0004] In recent years, as a new gas drainage means, the hydraulic slotting technology has received wide attention for its high efficiency and environmental protection characteristics. This technology greatly improves the gas drainage efficiency by introducing super high-pressure water to precisely cut slots in the coal seam. However, the implementation of this advanced technology faces severe challenges, and the most critical one is that the structure of the conventional drilling rig power head cannot convey (withstand) super high-pressure water (100 MPa).

[0005] Specifically, the design and material selection of the existing drilling rig power head do not take into account the stringent requirements of super high-pressure water transmission. When attempting to use super high-pressure water for hydraulic slotting in a conventional drilling rig, due to the internal structure and materials of the power head being unable to withstand such high water pressure, leakage and damage often occur. This not only causes waste of water resources, but more importantly, it seriously affects the continuity and efficiency of the drilling operation, and may even pose a potential threat to the safety of the mine. The leaked high-pressure water may cause equipment failures and even casualties.

[0006] In addition, there are also deficiencies in the connection and sealing of the existing drilling rig power head. When transmitting high-pressure water, if the connection and sealing structure are not firm and reliable enough, leakage problems are likely to occur. This will not only reduce the efficiency of the drilling operation, but may also cause environmental pollution.

[0007] In summary, there are many problems and limitations in the power head device for coal mine gas drainage boreholes in transmitting ultra-high pressure water. These problems not only limit the wide application of the hydraulic slotting technology in the field of coal mine gas drainage, but also pose a potential threat to the safety and mining efficiency of the mine. Therefore, it is necessary to conduct in-depth research and improvement on the existing drill power head structure to meet the new requirements and challenges of coal mine gas drainage. Summary of the Invention

[0008] In view of this, the purpose of the present invention is to provide an ultra-high pressure power head device for coal mine gas drainage boreholes to solve the existing problems.

[0009] To achieve the above purpose, the present invention provides the following technical solution: An ultra-high pressure power head device for coal mine gas drainage boreholes includes a water swivel, a connecting rod, a main shaft, and a driving drill pipe; the water swivel is connected to the connecting rod through a conical surface fit and an end face sealing structure, the connecting rod passes through the main shaft and is connected to the driving drill pipe by a taper thread connection with a double seal ring sealing structure, and an axial compensation spring is also provided between the main shaft and the connecting rod; the water swivel, the connecting rod, and the driving drill pipe are axially connected and communicated.

[0010] Optionally, the conical surface fit angle between the water swivel and the connecting rod is 55° - 65°.

[0011] Optionally, the conical surface fit angle is preferably 60°.

[0012] Optionally, the axial compensation spring is sleeved on the outer periphery of the connecting rod, located between the water swivel and the main shaft, and the spring compression amount forms an axial gap of 1 - 3 mm.

[0013] Optionally, the double seal rings at the taper thread connection include two O-ring seals, which are respectively arranged at the front and rear positions of the taper thread connection part.

[0014] Optionally, the main shaft is a hollow shaft structure, and the inner diameter thereof has a fit clearance of 0.5 - 1 mm with the outer diameter of the connecting rod.

[0015] Optionally, the driving drill pipe adopts a hollow structure, and the inner hole diameter thereof is connected with the inner hole diameter of the connecting rod in an equal diameter manner.

[0016] Optionally, the sealing structure includes a second seal ring.

[0017] The beneficial effects of the present invention are as follows:

[0018] First of all, this device solves the problem that the conventional drill power head cannot transmit ultra-high pressure water. By adopting a new connection and sealing structure, it is ensured that the inside of the power head can withstand and transmit ultra-high pressure water up to 100 MPa. This improvement enables the hydraulic slotting technology to be widely applied in the field of coal mine gas drainage, thus greatly improving the gas drainage efficiency.

[0019] Secondly, the device improves the continuity and efficiency of the drilling operation. Since it can stably transmit ultra-high pressure water, it avoids operation interruptions and equipment failures caused by leakage and damage. This not only reduces the time and cost of downtime for maintenance, but also improves the overall efficiency of the drilling operation.

[0020] In addition, the device helps to enhance the safety of the mine. Traditional drill power heads are prone to leakage when transmitting high-pressure water, posing a potential threat to the safety of the mine. The new ultra-high pressure power head device effectively reduces the leakage risk by optimizing the connection and sealing structure, thus enhancing the safety of the operation environment.

[0021] Finally, the application of the device is also conducive to environmental protection and sustainable development. As an efficient means of gas drainage, the hydraulic slotting technology can reduce gas emissions during coal mining and reduce pollution to the atmospheric environment. At the same time, by improving the gas drainage efficiency, gas can also be utilized as a clean energy source, contributing to the green transformation and sustainable development of the coal mining industry.

[0022] In summary, the research and application of an ultra-high pressure power head device for coal mine gas drainage boreholes bring many beneficial effects, including solving technical problems, improving operation efficiency, enhancing mine safety, and promoting environmental protection and sustainable development. This innovative achievement is of great significance for promoting the technological progress and industrial upgrading of the coal mining industry.

[0023] Other advantages, objectives and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in preferred detail below in conjunction with the drawings, wherein:

[0025] Figure 1 is the overall structural schematic diagram of the present invention;

[0026] Figure 2 is Figure 1 the enlarged view of A in

[0027] Figure 3 is Figure 1 the enlarged view of B in

[0028] Reference numerals: water braid 1, spring 2, main shaft 3, connecting rod 4, sealing ring 5, active drill pipe 6, second sealing ring 7. Detailed implementation manners

[0029] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0030] Among them, the attached drawings are only for illustrative purposes, showing only schematic diagrams, not physical diagrams, and should not be construed as a limitation to the present invention; in order to better illustrate the embodiments of the present invention, some components in the attached drawings will be omitted, enlarged or reduced, which does not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the attached drawings may be omitted.

[0031] In the attached drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship, it is based on the orientation or positional relationship shown in the attached drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the attached drawings are only for illustrative purposes and should not be construed as a limitation to the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0032] Please refer to Figures 1 to 3 , which is a super high-pressure power head device for coal mine gas drainage boreholes. Its structure includes components such as a water swivel 1, a spring 2, a main shaft 3, a connecting rod 4, a sealing ring 5, and a driving drill pipe 6.

[0033] Embodiment 1,

[0034] Water swivel 1: As the water inlet component of the device, it is used to introduce external water source into the device. A special designed conical surface fit plus end face seal structure is used to connect the water swivel 1 and the connecting rod 4;

[0035] In this embodiment, the angle of the conical surface fit is preferably 60° (the angle selection can be between 55° - 65°) to ensure good sealing performance under super high-pressure conditions.

[0036] In this embodiment, the sealing structure includes a second sealing ring 7 for enhancing the sealing effect.

[0037] Spring 2: As an axial compensation spring, it is sleeved on the outer periphery of the connecting rod 4 and is located between the water braid 1 and the main shaft 3. The compression amount of the spring 2 correspondingly forms an axial gap of 1-3 mm (gap at P) for realizing the telescopic amount of the active drill pipe 6 when connecting the next drill pipe, and preventing the thread from jamming.

[0038] Main shaft 3: It has a hollow shaft structure and is used to accommodate the connecting rod 4 and transmit water flow. A fitting gap of 0.5-1 mm is maintained between the inner diameter of the main shaft 3 and the outer diameter of the connecting rod 4 to ensure unobstructed water flow and stable connection.

[0039] Connecting rod 4: The connecting rod 4 passes through the main shaft 3 and is connected to the active drill pipe 6 by taper threads.

[0040] In this embodiment, in order to ensure that ultra-high pressure water does not leak during transmission, the taper thread connection is sealed with a double sealing ring 5 (such as two O-ring seals), which are respectively arranged at the front and rear positions of the taper thread connection part to ensure that ultra-high pressure water does not leak during transmission.

[0041] Active drill pipe 6: The active drill pipe 6 is designed with a hollow structure, and the inner hole diameter thereof is the same as the inner hole diameter of the connecting rod 4 to ensure that water flow can smoothly pass from the water braid 1 through the connecting rod 4, the main shaft 3 and finally reach the inside of the drill hole.

[0042] Embodiment 2

[0043] In this embodiment, its working principle includes: As shown in Figure 1 The water braid 1 and the connecting rod 4 are connected and sealed by a 60° conical surface plus an end face sealing ring structure. The connecting rod 4 passes through the main shaft 3 and is connected to the active drill pipe 6 by taper threads and double sealing rings to ensure that high-pressure water does not leak when entering the water braid, passing through the connecting rod and reaching the active drill pipe. Compared with the prior art, a new connection and sealing structure is adopted to enable the transmission of ultra-high pressure water inside the power head.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. An ultra-high pressure power head device for coal mine gas extraction drilling, characterized in that: Including water braid, connecting rod, main shaft and active drill pipe; The water braid is connected to the connecting rod through a conical surface matching and an end face sealing structure. The connecting rod passes through the main shaft and is connected to the active drill rod by a conical thread matching double sealing ring sealing structure. An axial compensation spring is also provided between the main shaft and the connecting rod. The water braid, the connecting rod and the active drill rod are connected along the axis.

2. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 1, characterized in that: The matching angle between the conical surface of the water braid and the connecting rod is 55°-65°.

3. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 2 is characterized in that: The cone fit angle is preferably 60°.

4. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 1 is characterized in that: The axial compensation spring is sleeved on the outer periphery of the connecting rod and is located between the water braid and the main shaft. The spring compression amount forms an axial gap of 1-3mm correspondingly.

5. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 1 is characterized in that: The double sealing rings at the tapered thread connection include two O-rings, which are respectively arranged at the front and rear positions of the tapered thread connection part.

6. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 1, characterized in that: The main shaft is a hollow shaft structure, and its inner diameter maintains a matching clearance of 0.5-1mm with the outer diameter of the connecting rod.

7. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 1 is characterized in that: The active drill rod adopts a hollow structure, and the inner hole diameter thereof is connected to the inner hole diameter of the connecting rod in an equal diameter.

8. The ultra-high pressure power head device for coal mine gas extraction drilling according to claim 1 is characterized in that: The sealing structure includes a second sealing ring.

Images