Drill rod

Abstract

The utility model belongs to the field of drilling tools, and particularly relates to a drill rod. Comprising a first rod body, a second rod body and a third rod body, the first rod body, the second rod body and the third rod body are fixedly connected; the central axes of the first rod body, the second rod body and the third rod body are the same; a first threaded groove extending towards the direction of the second rod body along the circumferential direction of the first rod body is formed in the peripheral surface of the first rod body; the second rod body comprises a first bearing part and a first transition part; the second threaded groove is formed in the peripheral face of the first transition part and the peripheral face of the first bearing part, the second threaded groove and the first threaded groove are integrally formed, and after the first threaded groove is in threaded connection with the drill bit, when the drill bit drills holes, stress concentrated at the threaded connection position of the drill bit and the first rod body can be transited to the second rod body through the second threaded groove; therefore, the situation that after the first rod body is in threaded connection with the drill bit, stress at the threaded connection position is excessively concentrated in the using process of the drill bit, and consequently the service life of the drill rod is shortened is avoided.

Description

Technical Field

[0001] The utility model belongs to the field of drilling tools, and particularly relates to a drill rod. Background Art

[0002] A drill rod is a tool that connects a drill bit and a rock drill in underground engineering. It is usually made of metal and has certain strength and hardness. In actual use, the drill rod is subjected to various stresses such as tension, compression, bending, torsion, and high-frequency impact. Therefore, its material and manufacturing process need to be specially designed and processed to ensure its reliability and durability in harsh working environments. The failure form of the drill rod is usually stress corrosion fatigue fracture. Therefore, choosing the appropriate material and treatment process is crucial for improving the service life of the drill rod.

[0003] Most of the existing drill rods are provided with threaded grooves at the connection with the drill bit. The drill rod is threadedly connected to the drill bit. During the use of the drill rod, under the action of various stresses such as tension, compression, bending, torsion, and high-frequency impact, the stress at the threaded connection between the drill rod and the drill bit will be too concentrated. Under the long-term high-stress action, the service life of the drill rod will be greatly reduced. Summary of the Utility Model

[0004] To solve the problem that during the use of the existing drill rod, stress will concentrate at the threaded connection between the drill rod and the drill bit, thereby reducing the service life of the drill rod, the utility model provides a drill rod.

[0005] This embodiment provides a drill rod, including:

[0006] A first rod body, a second rod body, and a third rod body; the first rod body, the second rod body, and the third rod body are fixedly connected; the central axes of the first rod body, the second rod body, and the third rod body are the same; a first threaded groove extending in the circumferential direction of the first rod body towards the second rod body is provided on the outer peripheral surface of the first rod body; the second rod body includes a first bearing portion and a first transition portion; one end of the first transition portion is fixedly connected to one end of the first bearing portion, and the other end is fixedly connected to one end of the first rod body. The outer circumference of the cross-sectional area of the first transition portion is circular, and the cross-sectional area of the first transition portion gradually increases from one end extending towards the first bearing portion to the other end; a second threaded groove is provided on the outer peripheral surface of the first transition portion and the outer peripheral surface of the first bearing portion, and the second threaded groove is integrally formed with the first threaded groove; the other end of the first bearing portion is fixedly connected to the third rod body.

[0007] In some embodiments, the third rod body includes a second bearing portion and a second transition portion, one end of the second transition portion is fixedly connected to the second bearing portion, and the other end is fixedly connected to one end of the first bearing portion.

[0008] In some embodiments, the outer periphery of the cross-sectional area of the second transition portion is circular, and the cross-section of the second transition portion gradually decreases in the direction of the first bearing portion along the axis of the third rod.

[0009] In some embodiments, the sum of the length of the first transition portion and the length of the first bearing portion is M1, the length of the second transition portion is M2, and the ratio of M1 to M2 is 1.2 to 1.4.

[0010] In some embodiments, the connecting end surface between the first transition portion and the first rod transitions to an arc surface.

[0011] In some embodiments, the maximum diameter of the outer periphery of the first transition portion is L1, the minimum diameter is L2, the diameter of the first rod is L3, and L1 is equal to L3; the ratio of L2 to L3 is 0.94 to 0.98.

[0012] In some embodiments, the ratio of L2 to L3 is 0.96.

[0013] In some embodiments, the length of the first rod is S1, the length of the second rod is S2, and the ratio of S1 to S2 is 1.85 to 1.98.

[0014] In some embodiments, the ratio of S1 to S2 is 1.9.

[0015] In some embodiments, the material of the third rod is hexagonal hollow steel.

[0016] To solve the problem that in the existing drill rod, stress will concentrate at the threaded connection between the drill rod and the drill bit during use, thereby reducing the service life of the drill rod, the present utility model has the following advantages:

[0017] 1. By providing a second thread groove on the outer peripheral surface of the first transition portion and the outer peripheral surface of the first bearing portion, and the second thread groove is integrally formed with the first thread groove. When the first thread groove is threadedly connected to the drill bit, during drilling, the stress concentrated at the threaded connection between the drill bit and the first rod can be transferred to the second rod through the second thread groove, thereby avoiding the stress at the threaded connection being too concentrated during the use of the drill bit after the first rod is threadedly connected to the drill bit, thus reducing the service life of the drill rod.

[0018] 2. By setting the outer diameter of the second thread groove to be smaller than the outer diameter of the first thread groove, the groove of the second thread groove is shallower, which is beneficial to reducing the stress concentration during heat treatment when the second rod is heat-treated. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of a drill rod;

[0020] Figure 2 is Figure 1 The partial enlarged schematic view of part A in

[0021] In the figure: 10, the first rod body; 20, the second rod body; 21, the first bearing part; 22, the first transition part; 30, the third rod body; 31, the second bearing part; 32, the second transition part. Detailed implementation manners

[0022] The present disclosure will now be described with reference to several exemplary embodiments. It should be understood that these embodiments are described only to enable those of ordinary skill in the art to better understand and thus implement the present disclosure, rather than to imply any limitation on the scope of the present disclosure.

[0023] As used herein, the term "comprising" and its variants are to be construed as open-ended terms meaning "including but not limited to". The term "based on" is to be construed as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be construed as "at least one embodiment". The term "another embodiment" is to be construed as "at least one other embodiment". The orientation or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc. are based on the orientation or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation, or be constructed and operated in a specific orientation. Also, some of the above terms may be used to represent other meanings in addition to representing orientation or positional relationships. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present application can be understood according to specific circumstances. In addition, the terms "installed", "arranged", "provided with", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral structure; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, or there may be internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, the meaning of "a plurality" is two or more.

[0024] This embodiment discloses a drill rod, as Figure 1 , Figure 2 shown, including:

[0025] A first rod body 10, a second rod body 20, and a third rod body 30; the first rod body 10, the second rod body 20, and the third rod body 30 are fixedly connected; the central axes of the first rod body 10, the second rod body 20, and the third rod body 30 are the same; a first thread groove (not shown in the figure) extending in the circumferential direction of the first rod body 10 towards the second rod body 20 is provided on the outer peripheral surface of the first rod body 10; the second rod body 20 includes a first bearing portion 21 and a first transition portion 22; one end of the first transition portion 22 is fixedly connected to one end of the first bearing portion 21, and the other end is fixedly connected to one end of the first rod body 10. The outer circumference of the cross-sectional area of the first transition portion 22 is circular, and the cross-sectional area of the first transition portion 22 gradually increases from one end extending towards the first bearing portion 21 to the other end; a second thread groove (not shown in the figure) is provided on the outer peripheral surface of the first transition portion 22 and the outer peripheral surface of the first bearing portion 21, and the second thread groove is integrally formed with the first thread groove; the other end of the first bearing portion 21 is fixedly connected to the third rod body 30.

[0026] In this embodiment, by providing a second thread groove on the outer peripheral surface of the first transition portion 22 and the outer peripheral surface of the first bearing portion 21, and the second thread groove is integrally formed with the first thread groove. When the first thread groove is threadedly connected to the drill bit, during drilling, the stress concentrated at the threaded connection between the drill bit and the first rod body 10 can be transferred to the second rod body 20 through the second thread groove, thereby avoiding the stress at the threaded connection being too concentrated during the use of the drill bit after the first rod body 10 is threadedly connected to the drill bit, and thus reducing the service life of the drill rod.

[0027] Moreover, by setting the outer diameter of the second thread groove to be smaller than the outer diameter of the first thread groove, the groove of the second thread groove is shallower, which is beneficial to reducing the heat treatment stress concentration during the heat treatment of the second rod body 20.

[0028] In some embodiments, as Figure 1 shown, the third rod body 30 includes a second bearing portion 31 and a second transition portion 32. One end of the second transition portion 32 is fixedly connected to the second bearing portion 31, and the other end is fixedly connected to one end of the first bearing portion 21.

[0029] In this embodiment, the third rod body 30 includes a second bearing portion 31 and a second transition portion 32. One end of the second transition portion 32 is fixedly connected to the second bearing portion 31, and the other end is fixedly connected to one end of the first bearing portion 21, which can make the force between the second rod body 20 and the first rod body 10 transition more evenly during drilling, so that the torsion force received by the third rod body 30 is more uniform.

[0030] In some embodiments, as Figure 1 shown, the outer periphery of the cross-sectional area of the second transition portion 32 is circular, and the cross-section of the second transition portion 32 gradually decreases in the axial direction of the third rod body 30 toward the first bearing portion 21.

[0031] In this embodiment, by making the outer periphery of the cross-sectional area of the second transition portion 32 circular and the cross-section of the second transition portion 32 gradually decrease in the axial direction of the third rod body 30 toward the first bearing portion 21, the force between the second rod body 20 and the first rod body 10 can be made to transition more evenly, so that the torsion force received by the third rod body 30 is more uniform, and the situation where the service life of the drill rod is greatly reduced due to uneven torque transmission between the second rod body 20 and the third rod body 30 can be avoided.

[0032] In some embodiments, the sum of the length of the first transition portion 22 and the length of the first bearing portion 21 is M1, the length of the second transition portion 32 is M2, and the ratio of M1 to M2 is 1.2 to 1.4.

[0033] In this embodiment, the ratio of M1 to M2 is set to 1.2 to 1.4, so that the length of the second transition portion 32 is greater than the sum of the length of the first transition portion 22 and the length of the first bearing portion 21, and the situation where the compressive strength of the first transition portion 22 is greatly reduced due to the too long second thread groove can be prevented during the use of the drill rod.

[0034] In some embodiments, the connecting end surface of the first transition portion 22 and the first rod body 10 is transitioned to an arc surface.

[0035] In this embodiment, by setting the transition at the connecting end surface of the first transition portion 22 and the first rod body 10 to an arc surface, the stress between the first transition portion 22 and the first rod body 10 can be made to transition evenly.

[0036] In some embodiments, the maximum diameter of the outer periphery of the first transition portion 22 is L1, the minimum diameter is L2, the diameter of the first rod body 10 is L3, and L1 is equal to L3; the ratio of L2 to L3 is 0.94 to 0.98.

[0037] In this embodiment, by setting the ratio of L2 to L3 to be 0.94 - 0.98, the difference between the maximum and minimum diameters of the outer periphery of the first transition portion 22 is not too large, which can ensure the torsional strength resistance of the first transition portion 22.

[0038] In some embodiments, the ratio of L2 to L3 is 0.96.

[0039] In this embodiment, as a preferred solution, the ratio of L2 to L3 is 0.96.

[0040] In some embodiments, the length of the first rod body 10 is S1, the length of the second rod body 20 is S2, and the ratio of S1 to S2 is 1.85 - 1.98.

[0041] In this embodiment, the length of S1 is about 81 mm. As a preference, the ratio of S1 to S2 is 1.9.

[0042] In some embodiments, the material of the third rod body 30 is hexagonal hollow steel.

[0043] The working principle of the present utility model is as follows:

[0044] By providing a second thread groove on the outer peripheral surface of the first transition portion 22 and the outer peripheral surface of the first bearing portion 21, and the second thread groove is integrally formed with the first thread groove. When the first thread groove is thread - connected to the drill bit, during the drilling of the drill bit, the stress concentrated at the thread connection between the drill bit and the first rod body 10 can be transferred to the second rod body 20 through the second thread groove, thereby avoiding the stress concentration at the thread connection during the use of the drill bit, which may reduce the service life of the drill rod.

[0045] Those of ordinary skill in the art can understand that the above - mentioned embodiments are specific cases for implementing the present disclosure, and in practical applications, various changes can be made in form and details without departing from the spirit and scope of the present disclosure.

Claims

1. A drill rod, characterized in that: The drill rod comprises: The first rod body, the second rod body, and the third rod body; the first rod body, the second rod body, and the third rod body are fixedly connected; the central axes of the first rod body, the second rod body, and the third rod body are the same; the outer circumferential surface of the first rod body is provided with a first thread groove extending along the circumference of the first rod body toward the second rod body; the second rod body includes a first bearing portion and a first transition portion; one end of the first transition portion is fixedly connected to one end of the first bearing portion, and the other end is fixedly connected to one end of the first rod body, the outer circumference of the cross-sectional area of ​​the first transition portion is circular, and the area of ​​the cross-sectional area of ​​the first transition portion gradually increases from one end on the side where the first bearing portion is located to the other end; the outer circumferential surface of the first transition portion and the circumferential surface of the first bearing portion are provided with a second thread groove, and the second thread groove is integrally formed with the first thread groove; the other end of the first bearing portion is fixedly connected to the third rod body.

2. A drill rod according to claim 1, characterized in that: The third rod body includes a second bearing portion and a second transition portion, wherein one end of the second transition portion is fixedly connected to the second bearing portion, and the other end of the second transition portion is fixedly connected to one end of the first bearing portion.

3. A drill rod according to claim 2, characterized in that: The outer periphery of the cross-sectional area of ​​the second transition portion is circular, and the cross-sectional area of ​​the second transition portion gradually decreases along the third rod body axis direction toward the first bearing portion.

4. A drill rod according to claim 2, characterized in that: The sum of the length of the first transition portion and the length of the first bearing portion is M1, the length of the second transition portion is M2, and the ratio of M1 to M2 is 1.2-1.

4.

5. A drill rod according to claim 1, characterized in that: The connecting end surface between the first transition portion and the first rod body transitions to a curved surface.

6. A drill rod according to claim 1, characterized in that: The maximum diameter of the outer circumference of the first transition portion is L1, the minimum diameter is L2, the diameter of the first rod body is L3, L1 is equal to L3; the ratio of L2 to L3 is 0.94-0.

98.

7. A drill rod according to claim 6, characterized in that: The ratio of L2 to L3 is 0.

96.

8. A drill rod according to claim 1, characterized in that: The length of the first rod is S1, the length of the second rod is S2, and the ratio of S1 to S2 is 1.85-1.

98.

9. A drill rod according to claim 8, characterized in that: The ratio of S1 to S2 is 1.

9.

10. A drill rod according to claim 1, characterized in that: The third rod body is made of hexagonal hollow steel.

Images