Hollow universal joint

Abstract

The invention discloses a hollow universal joint, and relates to the technical field of offshore drilling equipment, the hollow universal joint comprises a hollow inner rod, an overflowing joint and a rotor connecting joint, connecting structures are arranged between the overflowing joint and the hollow inner rod, and connecting structures are arranged between the rotor connecting joint and the hollow inner rod; the connecting structure comprises a supporting seat and an inner ball seat, a first sealing gap is formed between the supporting seat and the inner ball seat, an inner rubber sheet is arranged in the first sealing gap, a torque transmission block is fixedly arranged outside the hollow inner rod, grooves are formed in the positions, corresponding to the torque transmission block, of the inner walls of the overflowing connector and the rotor connecting connector, and an outer ball seat is fixedly arranged outside the hollow inner rod. The end, close to the hollow inner rod, of the overflowing connector or the rotor connecting connector is in threaded connection with a pressing ring, a second sealing gap is formed between the pressing ring and the outer ball seat, and an outer rubber sheet is arranged in the second sealing gap and fixedly arranged on the hollow inner rod. The hollow universal joint is simple in structure, an instrument can penetrate through the hollow universal joint, and stable signal transmission is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of marine drilling equipment, in particular to a hollow universal joint. Background Art

[0002] The screw universal joint is a component in the screw drilling tool. There are two commonly used universal joints: petal type and ball joint type. The petal universal joint relies on the petal structure to transmit torque, but the root of the petal is subject to a large bending moment and is easily broken from the root of the petal. The ball joint type relies on the key block to transmit torque. Since the key block is in point contact with the outer casing, it is easy to be crushed. Moreover, most of the current universal joints are solid structures, which cannot realize the wired transmission of near-drill bit measurement parameters to the upper part of the screw. There are also hollow universal joints for rotary steerable drilling, which use a coupling to achieve the universal function. The interior of the universal joint fork is hollow, and the line can pass through the inside, but the structure is complex, there is a risk of failure, and it is not easy to repair after failure. Summary of the invention

[0003] The purpose of the present invention is to provide a hollow universal joint to solve the problems existing in the above-mentioned prior art, with a simple structure and the possibility of passing instruments inside to achieve stable signal transmission.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a hollow universal joint, comprising a hollow inner rod and a flow joint and a rotor connection joint respectively arranged at two ends of the hollow inner rod, a connection structure is arranged between the flow joint and the hollow inner rod, and between the rotor connection joint and the hollow inner rod; the connection structure comprises a support seat and an inner ball seat sequentially arranged in the flow joint or the rotor connection joint, a first sealing gap is formed between the support seat and the inner ball seat, an inner rubber is arranged in the first sealing gap, the inner rubber has a connection portion that can be threadedly connected to the hollow inner rod, a torque transmission block is fixedly arranged outside the hollow inner rod, a groove is provided on the inner wall of the flow joint and the rotor connection joint corresponding to the torque transmission block, an outer ball seat is fixedly arranged outside the hollow inner rod, a pressure ring is threadedly connected to one end of the flow joint or the rotor connection joint close to the hollow inner rod, a second sealing gap is formed between the pressure ring and the outer ball seat, an outer rubber is arranged in the second sealing gap, and the outer rubber is fixedly arranged on the hollow inner rod.

[0006] Preferably, a flow hole is provided on the flow joint.

[0007] Preferably, the connecting portion is made of metal.

[0008] Preferably, the inner rubber has a sealing portion made of rubber material, and the sealing portion is arranged in the first sealing gap.

[0009] Preferably, the sealing portion is vulcanized and fixed to the connecting portion.

[0010] Preferably, the outer rubber and the hollow inner rod are fixed by vulcanization or bundling.

[0011] Preferably, the flow joint and the rotor connection joint are both provided with an oil filling hole connected with the groove, and a plug is provided at the oil filling hole.

[0012] Compared with the prior art, the present invention has achieved the following technical effects:

[0013] The hollow universal joint provided by the present invention has a large-caliber hollow structure formed inside the hollow inner rod, and instruments can be passed through the interior to achieve stable signal transmission; an inner rubber and an outer rubber, and a double rubber sheath structure are adopted, and the internal spaces of the two rubbers can be filled with oil to improve the flexibility and reliability of the hollow universal joint; the overall structure of the device is simple, and it is easy to install and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 A schematic diagram of the overall structure of the hollow universal joint provided by the present invention;

[0016] Figure 2 for Figure 1 Middle AA section view;

[0017] In the figure: 1-current flow joint; 2-support seat; 3-inner ball seat; 4-inner rubber; 5-outer ball seat; 6-pressure ring; 7-outer rubber; 8-hollow inner rod; 9-rotor connecting joint; 10-torsion transmission block; 11-plug. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The purpose of the present invention is to provide a hollow universal joint to solve the problems existing in the prior art, with a simple structure and the possibility of passing instruments inside to achieve stable signal transmission.

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] The present invention provides a hollow universal joint, such as Figures 1-2 As shown, it includes a hollow inner rod 8 and a flow joint 1 and a rotor connection joint 9 respectively arranged at both ends of the hollow inner rod 8, the flow joint 1 is provided with an internal thread for connecting with the screw drive shaft, the rotor connection joint 9 is provided with an external thread, and a connection structure is provided between the flow joint 1 and the hollow inner rod 8 and between the rotor connection joint 9 and the hollow inner rod 8; the connection structure includes a support seat 2 and an inner ball seat 3 sequentially arranged in the flow joint 1 or the rotor connection joint 9, a first sealing gap is formed between the support seat 2 and the inner ball seat 3, an inner rubber 4 is arranged in the first sealing gap, the inner rubber 4 has a connection portion that can be threadedly connected to the hollow inner rod 8, a torsion block 10 is fixedly arranged outside the hollow inner rod 8, and the flow joint 1 and A petal-shaped groove is provided on the inner wall of the rotor connecting joint 9 corresponding to the torque transmission block 10. After the torque transmission block 10 is installed on the hollow inner rod 8, it is aligned and installed inside the petal-shaped groove. An outer ball seat 5 is fixedly provided outside the hollow inner rod 8. The outer ball seat 5 is semi-ring-shaped, and two semi-rings can form a complete circular ring. A pressure ring 6 is threadedly connected to one end of the flow joint 1 or the rotor connecting joint 9 close to the hollow inner rod 8. A second sealing gap is formed between the pressure ring 6 and the outer ball seat 5. An outer rubber 7 is provided in the second sealing gap. The outer rubber 7 is installed between the outer ball seat 5 and the pressure ring 6. The size of the outer rubber 7 is slightly larger than the size of the second sealing gap. After the installation is completed, the outer rubber 7 is deformed under pressure to achieve sealing. The outer rubber 7 is fixedly provided on the hollow inner rod 8.

[0022] In some embodiments, a flow hole is provided on the flow joint 1, and the mud can enter the transmission shaft through the flow hole.

[0023] In some embodiments, the inner rubber 4 is a metal-rubber assembly, wherein the connecting portion is made of metal and is provided with external threads to achieve threaded connection between the inner rubber 4 and the hollow inner rod 8 .

[0024] In some embodiments, the inner rubber 4 has a sealing portion made of rubber material, which is arranged in the first sealing gap. The sealing portion is installed between the support seat 2 and the inner ball seat 3. The size of the sealing portion is slightly larger than the size of the first sealing gap formed between the support seat 2 and the inner ball seat 3. After the installation is completed, the sealing portion is deformed under pressure to achieve sealing.

[0025] In some embodiments, the sealing portion made of rubber is vulcanized and bonded to the connecting portion made of metal.

[0026] In some embodiments, the outer rubber 7 and the hollow inner rod 8 are fixed by vulcanization or bundling.

[0027] In some embodiments, an oil filling hole connected to the groove is provided on the flow joint 1 and the rotor connection joint 9. Furthermore, the oil filling hole can be connected to the space formed between the inner rubber 4 and the outer rubber 7. A plug 11 is provided at the oil filling hole. After the device is assembled, oil is filled through the oil filling hole and then blocked with the plug 11 to prevent leakage.

[0028] The hollow universal joint provided by the present invention has a large-caliber hollow structure formed inside the hollow inner rod 8, and instruments can be passed through the interior to achieve stable signal transmission; an inner rubber 4 and an outer rubber 7 are adopted, and a double rubber sheath structure is adopted, and the internal spaces of the two rubbers can be filled with oil to improve the flexibility of the hollow universal joint; the overall structure of the device is simple, and it is easy to install and maintain.

[0029] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A hollow universal joint, characterized in that: It comprises a hollow inner rod and a flow joint and a rotor connection joint respectively arranged at both ends of the hollow inner rod, and a connection structure is arranged between the flow joint and the hollow inner rod and between the rotor connection joint and the hollow inner rod; The connection structure includes a support seat and an inner ball seat which are sequentially arranged in the flow joint or the rotor connection joint, a first sealing gap is formed between the support seat and the inner ball seat, an inner rubber is arranged in the first sealing gap, the inner rubber has a connecting portion that can be threadedly connected to the hollow inner rod, a torque transmission block is fixedly arranged outside the hollow inner rod, grooves are provided on the inner walls of the flow joint and the rotor connection joint corresponding to the torque transmission block, an outer ball seat is fixedly arranged outside the hollow inner rod, a pressure ring is threadedly connected to one end of the flow joint or the rotor connection joint close to the hollow inner rod, a second sealing gap is formed between the pressure ring and the outer ball seat, an outer rubber is arranged in the second sealing gap, and the outer rubber is fixedly arranged on the hollow inner rod.

2. The hollow universal joint according to claim 1, characterized in that: The flow-through joint is provided with a flow-through hole.

3. The hollow universal joint according to claim 1, characterized in that: The connecting part is made of metal.

4. The hollow universal joint according to claim 3, characterized in that: The inner rubber has a sealing portion made of rubber material, and the sealing portion is arranged in the first sealing gap.

5. The hollow universal joint according to claim 4, characterized in that: The sealing portion is vulcanized and fixed on the connecting portion.

6. The hollow universal joint according to claim 1, characterized in that: The outer rubber and the hollow inner rod are fixed by vulcanization or bundling.

7. The hollow universal joint according to claim 1, characterized in that: The flow joint and the rotor connection joint are both provided with oil filling holes communicated with the groove, and plugs are provided at the oil filling holes.

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