Integrated jar capable of automatically adjusting underground operation pressure

Abstract

The utility model discloses an integrated jar capable of automatically adjusting underground operation pressure, which comprises a central shaft and a cylinder sleeved on the outer side of the central shaft, the central shaft is connected with the cylinder through an elastic piece for storing energy, and the central shaft is locked with the cylinder through a slip structure; the elastic part is arranged in a movable cavity, the movable cavity is located between the center shaft and the cylinder body, the movable cavity is communicated with an inner pressure cavity of the center shaft, the inner pressure cavity is elastically separated from an outer pressure environment through a constant pressure mechanism, and the inner pressure cavity is connected with the outer pressure environment through a pressure relief structure. According to the utility model, a constant pressure mechanism and a pressure relief structure are integrated on the central shaft, and automatic adjustment can be realized according to the change of internal pressure during operation, so that a better jarring jam releasing effect is obtained.

Description

Technical Field

[0001] The utility model relates to the technical field of petroleum downhole equipment, in particular to an integrated jar capable of automatically adjusting downhole operation pressure. Background Art

[0002] In oil well operations, whether drilling or logging, the equipment often gets stuck. Currently, most jars are used to release the stuck equipment. However, common jars are affected by the ambient temperature. When the temperature is high, the internal pressure increases, which may cause pressure loss and affect the service life of the equipment. Therefore, some jars are equipped with a structure to release the internal pressure temporarily. Although the abnormal increase of the internal pressure is avoided, the release of the internal pressure is intermittent and short-term, causing the internal pressure to fluctuate between the rise and fall. After the slips are unlocked, the acceleration generated by the release of the stored potential energy is unstable, thus affecting the effect of the jarring. Especially in an environment with large temperature fluctuations, the jarring effect is also greatly affected. Summary of the invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the utility model provides an integrated jar with automatic adjustment of downhole operating pressure, which integrates a constant pressure mechanism and a pressure relief structure into a central axis and can automatically adjust according to changes in internal pressure during operation, thereby obtaining a better jarring and unblocking effect.

[0004] Technical solution: To achieve the above-mentioned purpose, the utility model provides an integrated jar with automatic adjustment of downhole operating pressure, comprising a central axis and a cylinder sleeved on the outside of the central axis, wherein the central axis and the cylinder are connected by an elastic member for energy storage, and the central axis and the cylinder are locked by a cava structure; the elastic member is arranged in an active cavity, and the active cavity is located between the central axis and the cylinder, and the active cavity is connected to the internal pressure cavity of the central axis, and the internal pressure cavity is elastically separated from the external pressure environment by a constant pressure mechanism, and the internal pressure cavity is connected to the external pressure environment by a pressure relief structure.

[0005] Furthermore, the constant pressure mechanism includes a piston sleeve sleeved on the outside of the central axis, a piston cavity is formed between the piston sleeve and the central axis, a piston block is slidably arranged in the piston cavity, the piston block divides the piston cavity into two pressure chambers, the two pressure chambers are respectively connected to the external pressure environment and the internal pressure chamber, and the piston block is elastically connected to the end face of the piston cavity close to the external pressure environment connection port.

[0006] Furthermore, the pressure relief structure includes a pressure relief port connecting the internal pressure chamber and the external pressure environment, a top block is arranged outside the pressure port, the top block is pressed against the pressure relief port by a pre-stressed spring, and an end of the top block is adapted to the pressure port.

[0007] Furthermore, a guide hole is arranged outside the pressure release port, the top block cooperates with the guide hole piston in motion, and a through hole connecting the inner and outer end surfaces of the top block is arranged inside the top block.

[0008] Furthermore, the preload spring is axially arranged in the guide hole, one end of the preload spring is pressed against the top block, and the other end of the preload spring is pressed against the adjustment ring, and the adjustment ring is threadedly connected to the outer port of the guide hole.

[0009] Furthermore, an auxiliary chamber is formed between the middle part of the cylinder and the central axis, and the auxiliary chamber is connected to the external pressure environment; the part of the central axis located in the auxiliary chamber is provided with two opposite pressure surfaces, and the pressure surface facing the reset direction of the central axis is smaller than the pressure surface away from the reset direction of the central axis.

[0010] Beneficial effects: The utility model is an integrated jar with automatic adjustment of downhole operating pressure. This scheme sets a constant pressure mechanism so that the internal pressure of the equipment can be adaptively adjusted within an allowable range. The pure mechanical mechanism responds quickly, avoiding the extreme increase of internal pressure and affecting the stability of acceleration, thereby avoiding affecting the jarring and unblocking effect. By setting a pressure release structure, the internal pressure is released when the internal pressure increases to a certain threshold or may exceed the adjustable range of the constant pressure mechanism, and the constant pressure mechanism is used to maintain the stability of the pressure in the cavity, thereby reducing the influence of internal pressure fluctuations on the jarring effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Attached Figure 1 This is a schematic cross-sectional view of the overall structure of an embodiment of the utility model;

[0012] Attached Figure 2 This is a structural cross-sectional view of a constant pressure mechanism of an embodiment of the utility model;

[0013] Attached Figure 3 This is a structural diagram of a pressure relief structure according to an embodiment of the utility model. DETAILED DESCRIPTION

[0014] The utility model is further described below in conjunction with the accompanying drawings.

[0015] As attached Figure 1-3 The integrated jar with automatic adjustment of downhole operating pressure comprises a central axis 1 and a cylinder 2 sleeved on the outside of the central axis 1. The central axis 1 and the cylinder 2 are connected by an elastic member 3 for energy storage, and the central axis 1 and the cylinder 2 are locked by a slip structure 4. When it is necessary to release the jam by jarring, the slip structure is unlocked to release the stored potential energy, which is converted into kinetic energy of an internal hammer, and the jam release action is completed by multiple jarring.

[0016] The elastic member 3 is arranged in an active chamber 12, and the active chamber 12 is located between the central axis 1 and the cylinder 2. The active chamber 12 is connected to the internal pressure chamber 11 of the central axis 1, and the internal pressure chamber 11 is elastically separated from the external pressure environment by a constant pressure mechanism 5. The internal pressure chamber 11 is connected to the external pressure environment through a pressure relief structure 6.

[0017] During multiple shock operations, the expansion and contraction of the elastic part will cause the size of the internal space to change, thereby causing the internal pressure to change. When the elastic part releases the tensile potential energy, the internal space will shrink and the pressure will increase, which will increase the resistance to the hammer and cause the acceleration to decrease rapidly, thereby reducing the shock effect. This solution sets a constant pressure mechanism. When the internal pressure fluctuates due to normal operation, it will automatically balance with the external pressure environment. The size of the inner cavity is adjusted by elastic expansion, so that the pressure of the inner cavity will not increase significantly, so as to achieve the purpose of balanced acceleration of the hammer after the cava structure is unlocked, so as to achieve a better effect of unblocking. Among them, the hammer is a fixed structure located on the central axis. After releasing the potential energy, it impacts the cylindrical structure, thereby driving the overall structure and the clamping position to form a relative movement trend to achieve unblocking.

[0018] In addition, whether it is the relative slippage of the central axis relative to the cylinder or the temperature rise in the well, it will cause the internal pressure to increase, which may exceed the adjustable range of the constant pressure mechanism. This solution sets a pressure release structure. When the pressure in the internal pressure chamber reaches a certain threshold, the internal pressure chamber is opened to connect with the external pressure environment, thereby releasing excess pressure and avoiding the influence of excessive internal pressure on the shock effect. And when the internal pressure is released, the constant pressure mechanism will make corresponding dynamic adjustments according to the change of internal pressure, so that in the working environment with abnormally high temperature, it can also maintain a high shock release effect.

[0019] As attached Figure 2 As shown, the constant pressure mechanism 5 includes a piston sleeve 51 sleeved on the outside of the central axis 1, a piston cavity is formed between the piston sleeve 51 and the central axis 1, a piston block 52 is slidably arranged in the piston cavity, the piston block 52 divides the piston cavity into two pressure chambers 53, the two pressure chambers 53 are respectively connected to the external pressure environment and the internal pressure chamber 11, and the piston block 52 is elastically connected to the end face of the piston cavity close to the external pressure environment connection port.

[0020] The size of the pressure chambers on both sides is adjusted by the sliding of the piston block in the piston chamber. When the pressure in the internal pressure chamber tends to increase due to the reduction of space, the piston block is pushed to slide toward the external pressure environment, thereby compressing the spring structure connected to the piston block and converting the increased pressure into elastic potential energy storage, so that the pressure in the internal pressure chamber will not increase significantly. The potential energy stored in the spring structure can be used to push the central axis back to reset after a shock.

[0021] The pressure relief structure 6 includes a pressure relief port 61 connecting the internal pressure chamber 11 and the external pressure environment, a top block 63 is arranged outside the pressure port 61, the top block 63 is pressed against the pressure relief port 61 by a pre-compression spring 66, and the end of the top block 63 is adapted to the pressure port 61. A guide hole 62 is arranged outside the pressure relief port 61, the top block 63 and the guide hole 62 are piston-movement matched, and a through hole 64 is arranged inside the top block 63 to connect its inner and outer end surfaces.

[0022] A certain pre-pressure is applied by the pre-pressure spring, and the pre-pressure is set according to the required internal pressure threshold. The pre-pressure is used to press the top block against the pressure release port 61 to ensure that when the internal pressure is maintained within the normal range, the internal pressure chamber is isolated from the external pressure environment. When the internal pressure exceeds the threshold, the pre-pressure is overcome to push the top block open, thereby achieving the purpose of releasing the internal pressure.

[0023] Preferably, the guide hole is opened along the radial direction of the cylinder, the internal pressure cavity extends along the axis of the central axis, and the pressure relief port is located at the inner end center of the guide hole. The top block is matched with the guide hole piston movement to ensure that its inner and outer end surfaces are resistant to internal and external pressures, and its sliding movement is more stable. After the top block is pushed away from the pressure relief port, the internal pressure is released to the atmosphere through the through hole inside the top block. Figure 3 As shown, the inner end surface of the top block can be set to a pointed cone shape so as to better cooperate with the pressure relief port, and the inner port of the through hole can be divided into multiple ports evenly distributed on the cone surface.

[0024] Preferably, the pre-compression spring 66 is axially arranged in the guide hole 62, one end of the pre-compression spring 66 is pressed against the top block 63, and the other end is pressed against the adjustment ring 65, and the adjustment ring 65 is threadedly connected to the outer end of the guide hole 62. The distance between the adjustment ring and the pressure release port can be changed by adjusting the thread, thereby adjusting the applied pre-compression force, and then adjusting the pressure release threshold.

[0025] As attached Figure 1 As shown in b, an auxiliary chamber 7 is formed between the middle of the cylinder 2 and the central axis 1, and the auxiliary chamber 7 is connected to the external pressure environment; the part of the central axis 1 located in the auxiliary chamber 7 is provided with two opposite pressure surfaces, and the pressure surface facing the reset direction of the central axis 1 is smaller than the pressure surface away from the reset direction of the central axis 1. That is, a piston area difference is formed on the central axis at the auxiliary chamber position, which can assist in pushing the reset of the central axis of the jar under the action of external pressure.

[0026] Preferably, the elastic member 3 is a disc spring, as shown in the attached Figure 1 As shown in a in the middle, a disc spring can be added to the central axis to increase the impact speed during release after unlocking, thereby enhancing the shock force and further enhancing the shock effect.

[0027] The above is only a description of the preferred embodiment of the present invention. Ordinary technicians in this technical field can make several modifications and optimizations based on the above disclosure without departing from the above basic principles. These improvements and optimizations should be regarded as the understood protection scope of the present invention.

Claims

1. An integrated jar with automatic adjustment of downhole operation pressure, characterized in that: The invention comprises a central shaft (1) and a cylinder (2) sleeved on the outside of the central shaft (1); the central shaft (1) and the cylinder (2) are connected via an elastic member (3) for energy storage; and the central shaft (1) and the cylinder (2) are locked via a slip structure (4); The elastic member (3) is arranged in an active chamber (12), and the active chamber (12) is located between the central axis (1) and the cylinder (2). The active chamber (12) is connected to the internal pressure chamber (11) of the central axis (1), and the internal pressure chamber (11) is elastically separated from the external pressure environment by a constant pressure mechanism (5). The internal pressure chamber (11) is connected to the external pressure environment through a pressure relief structure (6).

2. The integrated jar with automatic downhole operation pressure adjustment according to claim 1, characterized in that: The constant pressure mechanism (5) comprises a piston sleeve (51) sleeved on the outside of the central axis (1), a piston chamber is formed between the piston sleeve (51) and the central axis (1), a piston block (52) is slidably arranged in the piston chamber, the piston block (52) divides the piston chamber into two pressure chambers (53), the two pressure chambers (53) are respectively connected to the external pressure environment and the internal pressure chamber (11), and the piston block (52) is elastically connected to the end face of the piston chamber close to the external pressure environment connection port.

3. The integrated jar with automatic downhole operation pressure adjustment according to claim 2 is characterized in that: The pressure relief structure (6) comprises a pressure relief port (61) connecting the internal pressure chamber (11) and the external pressure environment, a top block (63) is arranged on the outside of the pressure relief port (61), the top block (63) is pressed against the pressure relief port (61) by a pre-compression spring (66), and an end of the top block (63) is adapted to the pressure relief port (61).

4. The integrated jar with automatic downhole operation pressure adjustment according to claim 3 is characterized in that: A guide hole (62) is arranged outside the pressure release port (61), the top block (63) cooperates with the guide hole (62) in piston motion, and a through hole (64) is arranged inside the top block (63) to connect the inner and outer end surfaces thereof.

5. The integrated jar with automatic downhole operation pressure regulation according to claim 4, characterized in that: The preload spring (66) is axially arranged in the guide hole (62), one end of the preload spring (66) is pressed against the top block (63), and the other end is pressed against the adjustment ring (65), and the adjustment ring (65) is threadedly connected to the outer end of the guide hole (62).

6. The integrated jar with automatic downhole operation pressure regulation according to claim 1, characterized in that: An auxiliary chamber (7) is formed between the middle of the cylinder (2) and the central axis (1), and the auxiliary chamber (7) is connected to an external pressure environment; the portion of the central axis (1) located in the auxiliary chamber (7) is provided with two opposing pressure surfaces at a spacing, and the pressure surface facing the reset direction of the central axis (1) is smaller than the pressure surface away from the reset direction of the central axis (1).

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