A mechanical drill string stick-slip vibration monitoring device and method

Abstract

The present invention discloses a mechanical drill string stick-slip vibration monitoring device and method, which includes an upper sub, an upper sub connecting block, a spiral shaft, a spiral sleeve, a middle cylinder, a lower cylinder, a pressure relief hole housing, a lower sub connecting block, and a lower sub; the upper sub, the upper sub connecting block, the spiral shaft, the middle cylinder, and the lower cylinder are sequentially threadedly connected from top to bottom, and the spiral sleeve, the pressure relief hole housing, the lower sub connecting block, and the lower sub are sequentially threadedly connected from top to bottom; the lower end of the lower cylinder is located inside the lower sub connecting block; both ends of the disc spring are respectively fixed on the disc spring wear-resistant adjustment collar; the disc spring wear-resistant adjustment collar is fixed on the lower sub connecting block; there is a cavity between the middle cylinder and the pressure relief hole housing, the middle cylinder is provided with a channel communicating with the cavity, and the pressure relief hole housing is provided with a water eye located below the cavity. The present invention can perform a pressure reduction operation when stick-slip vibration occurs underground, and feed it back to the wellhead staff as a signal in time to quickly carry out relevant work, preventing damage to the drill string and bit connected below.

Description

Technical Field

[0001] The present invention relates to a mechanical drill string stick-slip vibration monitoring device and method, belonging to the technical field of drilling tools. Background Technique

[0002] With the development of the petroleum industry, the scope of oil and gas exploration and development has gradually advanced from shallow formations to deep formations, and the proportion of deep well and ultra-deep well oil and gas development has gradually increased, which has become the current trend of oil and gas development. In deep wells and ultra-deep wells, due to the larger length-diameter ratio and smaller stiffness of the drill string, stick-slip vibration is more likely to occur under the hindrance of the formation. The stick-slip vibration of the drill string means that during the drilling process, the rotary table receives the energy input at the wellhead and transmits it to the bottom of the well through the drill string, while the drill bit remains in a sticky state because it cannot overcome the formation resistance. After the energy accumulated by the drill string is sufficient to break the sticky state, the drill bit rotates at a high speed under a huge driving force. The stick-slip vibration of the drill string is manifested as the continuous alternating cycle of the stickiness and slippage of the drill bit. The speed and acceleration of the drill bit during the slippage stage are usually relatively high, which is likely to cause damage to the lower drill string and the drill bit, further affecting the drilling efficiency and development cost.

[0003] However, the phenomenon of stick-slip vibration is very difficult to capture during the drilling process. If the stick-slip vibration occurring downhole can be observed in time, relevant work can be carried out quickly to prevent the further intensification of the stick-slip vibration. Summary of the Invention

[0004] In order to overcome the problems in the prior art, the present invention provides a mechanical drill string stick-slip vibration monitoring device and method to avoid the situation that the drill string and the drill bit are damaged due to excessive torque caused by stick-slip vibration.

[0005] The technical solution provided by the present invention to solve the above technical problems is: a mechanical drill string stick-slip vibration monitoring device, including an upper sub, an upper sub connecting block, a spiral shaft, a spiral sleeve, a middle cylinder, a lower cylinder, a pressure relief hole housing, a lower sub connecting block, and a lower sub;

[0006] The upper sub, the upper sub connecting block, the spiral shaft, the middle cylinder, and the lower cylinder are sequentially threadedly connected from top to bottom, the spiral sleeve, the pressure relief hole housing, the lower sub connecting block, and the lower sub are sequentially threadedly connected from top to bottom, and a disc spring wear-resistant adjustment collar and a disc spring are sequentially sleeved on the lower end of the lower cylinder from top to bottom;

[0007] The spiral shaft is helically and fittingly installed inside the spiral sleeve. The pressure relief hole housing sleeves the lower end of the spiral sleeve, the middle cylinder, the lower cylinder, the disc spring wear-resistant adjustment collar, and the disc spring. The lower end of the lower cylinder is located inside the lower joint connection block. Both ends of the disc spring are respectively fixed on the disc spring wear-resistant adjustment collar. The disc spring wear-resistant adjustment collar is fixed on the lower joint connection block. There is a cavity between the middle cylinder and the pressure relief hole housing. A channel communicating with the cavity is provided on the middle cylinder. A water eye located below the cavity is provided on the pressure relief hole housing.

[0008] A further technical solution is that a shock-absorbing buffer ring is provided at the bottom of the upper joint connection block.

[0009] A further technical solution is that a sealing ring Ⅰ is provided between the spiral shaft and the spiral sleeve.

[0010] A further technical solution is that a sealing ring Ⅰ is provided between the lower cylinder and the pressure relief hole housing.

[0011] A further technical solution is that a sealing ring Ⅱ is provided between the lower cylinder and the lower joint connection block.

[0012] A mechanical drill string stick-slip vibration monitoring method is characterized by including the following steps:

[0013] Step S1: Preset the monitoring torque of the disc spring by adjusting the disc spring wear-resistant adjustment collar.

[0014] Step S2: Connect a mechanical drill string stick-slip vibration monitoring device to the drill string near the drill bit and conduct operations deep into the well.

[0015] During normal drilling, the torque received by the lower joint is constantly changing. The spiral shaft will drive the middle cylinder and the lower cylinder to continuously move up and down, squeezing the disc spring wear-resistant adjustment collar and the disc spring. The cavity formed by the cooperation will also move up and down with the middle cylinder. At this time, the drilling fluid flows into the mechanical drill string stick-slip vibration monitoring device. Part of the drilling fluid flows out at the lower joint, and the other part of the drilling fluid flows into the cavity formed by the cooperation of the middle cylinder, the lower cylinder, and the pressure relief hole housing through the preset channel at the middle cylinder.

[0016] When stick-slip vibration occurs underground, the torque received by the lower joint instantaneously increases. The spiral shaft will drive the middle cylinder and the lower cylinder to quickly move downward, squeezing the disc spring wear-resistant adjustment collar and the disc spring. The cavity formed by the cooperation will also move downward with the middle cylinder and the lower cylinder. When the torque increases to exceed the initially preset monitoring torque, the cavity communicates with the water eye on the pressure relief hole housing, and part of the drilling fluid flows out from the water eye for pressure reduction operation.

[0017] Step S5: When the staff at the wellhead observes the pressure reduction signal, perform relevant operations in a timely manner.

[0018] Step S6: After the stick-slip vibration disappears, the torque on the lower joint decreases. The disc spring generates a large elastic force due to compression, causing the spiral shaft, the middle cylinder, and the lower cylinder to move upward.

[0019] Step S7: When the torque decreases to the initially preset monitoring torque, the cavity separates from the water eye on the pressure relief hole housing, and the drilling fluid pressure gradually recovers, and the pressure reduction signal disappears.

[0020] The present invention has the following beneficial effects:

[0021] (1) The present invention can perform pressure reduction operations when stick-slip vibration occurs underground, and feed back the signal to the wellhead staff in time to quickly carry out relevant work, preventing damage to the drill string and bit due to stick-slip vibration.

[0022] (2) The present invention can preset the magnitude of the monitoring torque by adjusting the disc spring wear-resistant adjustment collar, and the torque adjustment range is wide.

[0023] (3) The present invention can achieve automatic reset after the stick-slip vibration disappears. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of the present invention;

[0025] Figure 2 is a schematic structural diagram of the spiral shaft;

[0026] Figure 3 is a sectional view of the spiral sleeve;

[0027] Figure 4 is a sectional view of the middle cylinder;

[0028] Figure 5 is a sectional view of the lower cylinder.

[0029] As shown in the figure: 1 - upper joint, 2 - upper joint connecting block, 3 - shock absorption buffer ring, 4 - sealing ring I, 5 - spiral shaft, 6 - spiral sleeve, 7 - middle cylinder, 8 - lower cylinder, 9 - water eye, 10 - disc spring wear-resistant adjustment collar, 11 - pressure relief hole housing, 12 - disc spring, 13 - sealing ring II, 14 - lower joint connecting block, 15 - lower joint. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] AsFigures 1 to 5 As shown in the figure, a mechanical drill string stick-slip vibration monitoring device of the present invention includes an upper sub 1, an upper sub connection block 2, a spiral shaft 5, a spiral sleeve 6, a middle cylinder 7, a lower cylinder 8, a pressure relief hole housing 11, a lower sub connection block 14, and a lower sub 15;

[0032] The upper sub 1, the upper sub connection block 2, the spiral shaft 5, the middle cylinder 7, and the lower cylinder 8 are threadedly connected in sequence from top to bottom. The spiral sleeve 6, the pressure relief hole housing 11, the lower sub connection block 14, and the lower sub 15 are threadedly connected in sequence from top to bottom. A disc spring wear-resistant adjustment collar 10 and a disc spring 12 are sleeved on the lower end of the lower cylinder 8 in sequence from top to bottom;

[0033] The spiral shaft 5 is helically fitted and installed in the spiral sleeve 6. The pressure relief hole housing 11 sleeves the lower end of the spiral sleeve 6, the middle cylinder 7, the lower cylinder 8, the disc spring wear-resistant adjustment collar 10, and the disc spring 12. The lower end of the lower cylinder 8 is located inside the lower sub connection block 14, and the lower disc spring wear-resistant adjustment collar presses on the upper end face of the lower sub connection block 14. There is a cavity between the middle cylinder 7, the lower cylinder 8 and the pressure relief hole housing 11. A channel communicating with the cavity is provided on the middle cylinder 7, and a water eye 9 is provided on the pressure relief hole housing 11 below the cavity. A shock-absorbing buffer ring 3 is provided at the bottom of the upper sub connection block 2.

[0034] The working principle of this embodiment is as follows: When drilling normally, the spiral shaft 5, the middle cylinder 7, and the lower cylinder 8 move up and down with the change of torque. At this time, the cavity is separated from the water eye 9, and the drilling fluid only flows out from the lower sub 15. When stick-slip vibration occurs downhole, the lower sub 15 stops rotating, and the spiral shaft 5, the middle cylinder 7, and the lower cylinder 8 move downward with the increase of torque, squeezing the disc spring 12 until the cavity communicates with the water eye 9 when the initial preset monitoring torque is reached. At this time, the drilling fluid can flow out from both the water eye 9 and the lower sub 15 for pressure reduction operation.

[0035] After the stick-slip vibration disappears, the lower sub 15 rotates again. Under the action of the disc spring 12, the spiral shaft 5, the middle cylinder 7, and the lower cylinder 8 move upward with the decrease of torque until the cavity is separated from the water eye 9 when it is lower than the initial preset monitoring torque. At this time, the drilling fluid only flows out from the lower sub 15.

[0036] As Figure 1 shown, in this embodiment, in order to improve the sealing effect, a preferred implementation is that a sealing ring Ⅰ4 is provided between the spiral shaft 5 and the spiral sleeve 6, a sealing ring Ⅰ4 is provided between the lower cylinder 8 and the pressure relief hole housing 11, and a sealing ring Ⅱ13 is provided between the lower cylinder 8 and the lower sub connection block 14.

[0037] A mechanical drill string stick-slip vibration monitoring method, the steps of which are:

[0038] S1. Preset the monitored torque of the disc spring 12 by adjusting the disc spring wear-resistant adjusting collar 10;

[0039] S2. Install the described mechanical drill string stick-slip vibration monitoring device on the drill string and carry out operations deep downhole;

[0040] S3. During normal drilling, the torque received by the lower sub 15 is constantly changing. The spiral shaft 5 will drive the middle cylinder 7 and the lower cylinder 8 to move up and down continuously, squeezing the disc spring wear-resistant adjusting collar 10 and the disc spring 12, and the cavity will also move up and down with the middle cylinder 7. At this time, the drilling fluid flows into the upper sub 1, and then the drilling fluid flows through the upper sub connecting block 2, the spiral shaft 5, and the middle cylinder 7 in sequence. In the middle cylinder 7, the drilling fluid is divided into two parts. One part of the drilling fluid then flows through the lower cylinder 8, the lower sub connecting block 14, and the lower sub 15 in sequence, and finally flows out at the lower sub 15, while the other part of the drilling fluid flows into the cavity formed by the cooperation of the middle cylinder 7, the lower cylinder 8, and the pressure relief hole housing 11 through a preset channel at the middle cylinder 7;

[0041] S4. When stick-slip vibration occurs downhole, the torque received by the lower sub 15 increases instantaneously. The spiral shaft 5 will drive the middle cylinder 7 and the lower cylinder 8 to move downward rapidly, squeezing the disc spring wear-resistant adjusting collar 10 and the disc spring 12, and the cavity will also move downward with the middle cylinder 7 and the lower cylinder 8. When the torque increases to exceed the initially preset monitored torque, the cavity communicates with the water eye 9 on the pressure relief hole housing 11, so that part of the drilling fluid in the cavity flows out from the water eye 9 for pressure reduction operation;

[0042] S5. When the staff at the wellhead observes the pressure reduction signal, carry out relevant operations in a timely manner;

[0043] S6. After the stick-slip vibration disappears, the torque received by the lower sub decreases. The disc spring 12 will generate a large elastic force due to compression, causing the spiral shaft 5, the middle cylinder 7, and the lower cylinder 8 to move upward;

[0044] S7. When the torque decreases to the initially preset monitored torque, the cavity is separated from the water eye 9 on the pressure relief hole housing 11, and the drilling fluid pressure gradually recovers, and the pressure reduction signal disappears.

[0045] As described above, it is not any form of limitation to the present invention. Although the present invention has been disclosed through the above embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to form equivalent embodiments with equivalent changes within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A mechanical drill string stick-slip vibration monitoring device, characterized in that, it includes an upper sub (1), an upper sub connecting block (2), a spiral shaft (5), a spiral sleeve (6), a middle cylinder (7), a lower cylinder (8), a pressure relief hole housing (11), a lower sub connecting block (14), and a lower sub (15); The upper sub (1), the upper sub connecting block (2), the spiral shaft (5), the middle cylinder (7), and the lower cylinder (8) are threadedly connected in sequence from top to bottom. The spiral sleeve (6), the pressure relief hole housing (11), the lower sub connecting block (14), and the lower sub (15) are threadedly connected in sequence from top to bottom. A disc spring wear-resistant adjustment collar (10) and a disc spring (12) are sleeved on the lower end of the lower cylinder (8) in sequence from top to bottom; The spiral shaft (5) is installed in the spiral sleeve (6) in a spiral fit. The pressure relief hole housing (11) sleeves the lower end of the spiral sleeve (6), the middle cylinder (7), the lower cylinder (8), the disc spring wear-resistant adjustment collar (10), and the disc spring (12). The lower end of the lower cylinder (8) is located inside the lower sub connecting block (14). Both ends of the disc spring (12) are fixed on the disc spring wear-resistant adjustment collar (10), and the disc spring wear-resistant adjustment collar (10) is fixed on the lower sub connecting block (14). There is a cavity between the middle cylinder (7) and the pressure relief hole housing (11). The middle cylinder (7) is provided with a channel communicating with the cavity. The pressure relief hole housing (11) is provided with a water eye (9) located below the cavity; When drilling normally, the spiral shaft (5), the middle cylinder (7), and the lower cylinder (8) move up and down with the change of torque. At this time, the cavity is separated from the water eye (9); When stick-slip vibration occurs underground, the lower sub (15) stops rotating. The spiral shaft (5), the middle cylinder (7), and the lower cylinder (8) move downward with the increase of torque, squeezing the disc spring (12), until the cavity communicates with the water eye (9) when the initial preset monitoring torque is reached; After the stick-slip vibration disappears, the lower sub (15) rotates again. Under the action of the disc spring (12), the spiral shaft (5), the middle cylinder (7), and the lower cylinder (8) move upward with the decrease of torque until the cavity is separated from the water eye (9) when it is lower than the initial preset monitoring torque.

2. The mechanical drill string stick-slip vibration monitoring device according to claim 1, characterized in that, a shock absorption and buffering ring (3) is provided at the bottom of the upper sub connecting block (2).

3. The mechanical drill string stick-slip vibration monitoring device according to claim 1, characterized in that, a sealing ring Ⅰ (4) is provided between the spiral shaft (5) and the spiral sleeve (6).

4. The mechanical drill string stick-slip vibration monitoring device according to claim 1, characterized in that, a sealing ring Ⅰ (4) is provided between the lower cylinder (8) and the pressure relief hole housing (11).

5. The mechanical drill string stick-slip vibration monitoring device according to claim 1, characterized in that, a sealing ring Ⅱ (13) is provided between the lower cylinder (8) and the lower sub connecting block (14).

6. A mechanical drill string stick-slip vibration monitoring method, characterized in that, it includes the following steps: Step S1: Preset the monitored torque of the disc spring (12) by adjusting the disc spring wear-resistant adjusting collar (10). Step S2: Connect the mechanical drill string stick-slip vibration monitoring device described in Claim 1 to the drill string near the drill bit and conduct operations deep downhole. Step S3: During normal drilling, the torque received by the lower sub (15) is constantly changing. The spiral shaft (5) drives the middle cylinder (7) and the lower cylinder (8) to move up and down continuously, squeezing the disc spring wear-resistant adjusting collar (10) and the disc spring (12). The cavity formed by their cooperation also moves up and down with the middle cylinder (7) and the lower cylinder (8). At this time, drilling fluid flows into the mechanical drill string stick-slip vibration monitoring device. Part of the drilling fluid flows out at the lower sub (15), and another part of the drilling fluid flows into the cavity formed by the cooperation of the middle cylinder (7), the lower cylinder (8), and the pressure relief hole housing (11) through a preset channel at the middle cylinder (7). Step S4: When stick-slip vibration occurs downhole, the torque received by the lower sub (15) increases instantaneously. The spiral shaft (5) drives the middle cylinder (7) and the lower cylinder (8) to move downward rapidly, squeezing the disc spring wear-resistant adjusting collar (10) and the disc spring (12). The cavity also moves downward with the middle cylinder (7) and the lower cylinder (8). When the torque increases to exceed the initially preset monitored torque, the cavity communicates with the water eye (9) on the pressure relief hole housing (11), and part of the drilling fluid flows out from the water eye (9) for pressure reduction operation. Step S5: When the staff at the wellhead observes the pressure reduction signal, perform relevant operations in a timely manner. Step S6: After the stick-slip vibration disappears, the torque received by the lower sub (15) decreases. The disc spring (12) generates a large elastic force due to compression, causing the spiral shaft (5), the middle cylinder (7), and the lower cylinder (8) to move upward. Step S7: When the torque decreases to the initially preset monitored torque, the cavity separates from the water eye (9) on the pressure relief hole housing (11), and the drilling fluid pressure gradually recovers, and the pressure reduction signal disappears.

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