CN105134079B - A kind of mechanical static backup automatic vertical drilling system - Google Patents

Abstract

The invention discloses a mechanical static pushing automatic vertical drilling system, which comprises a guide sleeve. The lower part of the guide sleeve is provided with a guide structure. The guide structure is driven by a driving mechanism. The guide sleeve is provided with a main shaft and an eccentric block. The sleeve is provided with a bearing, and the eccentric block is fixed on the bearing; the guide sleeve is provided with a drilling fluid flow channel, at least three first flow channels leading to the driving mechanism, and at least three second flow channels leading to the outside of the guide sleeve; There is also a valve structure on the bearing. When the eccentric block rotates, it can drive the valve structure to rotate. The part of the valve structure located on the side of the eccentric block can make the first flow channel and the second flow channel on this side conduct with the drilling fluid flow channel. The part of the valve structure on the side opposite to the eccentric block can close the second flow channel on this side, and only make the first flow channel communicate with the drilling fluid flow channel.

Description

A Mechanical Static Pushing Automatic Vertical Drilling System

technical field

The invention relates to the field of drilling equipment, in particular to a mechanical static pushing automatic vertical drilling system.

Background technique

At present, drilling engineering is an important means of resource and environmental exploration, and its research field is extending from the traditional surface to the polar regions, the ocean, and the deep part of the earth and the bottom of the ocean. Deep drilling will be an important means of deep earth exploration and the only way to obtain real objects deep in the earth. However, in the process of deep drilling, how to keep the wellbore vertical is a big problem. The problem of well deviation will directly restrict the drilling speed and drilling speed. Quality, and even the success or failure of the entire drilling project. For example, Songke No. 2 well intends to make the well depth reach 6,400 meters. With the continuous increase of well depth, the problem of well deviation will become more prominent and the harm will become more serious.

Many drilling projects, such as the Kola ultra-deep well in the former Soviet Union (the designed final hole depth is 15000m, the actual final hole depth is 12262m) and the German KTB main hole (the designed final hole depth is 10000m, the actual final hole depth is 9101m) are forced to finish early due to the uncontrollable hole deviation. hole. In order to solve this problem, a lot of theoretical analysis and field practice have been carried out at home and abroad, and anti-deflection methods such as rigid full-hole drilling tools, pendulum combined drilling tools, and off-axis drilling tools have been proposed successively. However, these methods are all at the expense of WOB. The passive anti-slant method that reduces the ROP in exchange for the anti-slant effect is not obvious, and even some formations cannot achieve the effect of anti-slant correction at all. Especially in the drilling construction of deep holes and ultra-deep holes, the effect of passive anti-slant methods is limited, and the construction time for deviation correction still accounts for a large proportion.

The emergence of automatic vertical drilling and rotary steerable drilling systems has brought major technological breakthroughs for deflection prevention and correction. Human intervention is required to automatically track the predetermined wellbore trajectory, which can successfully solve the problem of deflection prevention and correction in high-steep structures and complex formations with large dip angles. While ensuring the quality of the wellbore, it can release the drilling pressure and increase the ROP. The most important prerequisite for the main hole of the German KTB project to reach the depth of the final hole is the successful implementation of the vertical drilling strategy. The developed automatic vertical drilling system (VDS) was successfully applied to a hole depth range of 7500m, making KTB the world's most advanced drilling system at that time. The vertical borehole and the successful limitation of abrasive loads and torque provided the necessary prerequisites for a later implementation of the close clearance drilling and casing strategy. The development of the automatic vertical drilling system has further promoted the progress of the rotary steerable technology. Since the 1980s, foreign countries have carried out active anti-deviation technology research. Up to now, more than 10 companies have formed their own rotary steerable systems, and conducted field tests and applications, without exception, with vertical drilling capabilities. At present, there are mainly three companies with commercial application capabilities: Baker Hughes, Schlumberger and Halliburton.

The current static push-to-type automatic vertical drilling system mainly includes a guide sleeve that is arranged on the outside and relatively does not rotate. The lower part of the guide sleeve is used to connect the drill bit externally. There is a guide block driven by hydraulic pressure. When the well deviation is sensed, it sends a signal to the microprocessor in the guide sleeve to control the hydraulic system, so that the guide block protrudes outwards and pushes against the inner wall of the well to correct the well deviation. effect. But, there is following problem in existing above-mentioned automatic vertical drilling system:

First, the hydraulic drive system used to drive the guide block requires independent hydraulic pumps and other mechanisms, and the structure is complex, so that the size of the guide sleeve is too large to be applied to the drilling of small-diameter wellheads.

Second, the correction effect on the well deviation is not ideal, and there are large errors. The applicant found through a large number of engineering tests that one of the reasons for this error is that the structure design of the guide block is unreasonable and cannot be comprehensive, accurate and stable. play a guiding role.

Third, sensors such as gravity accelerometers are electronic devices, which cannot be used in boreholes with a temperature higher than 120°C due to the limitation of downhole temperature.

In view of this, the present invention is proposed.

Contents of the invention

The purpose of the present invention is to provide a mechanical static pushing automatic vertical drilling system.

In order to achieve the above object, the mechanical static pushing automatic vertical drilling system provided by the present invention includes a guide sleeve, the lower part of the guide sleeve is provided with a guide structure, and the guide structure is driven by a driving mechanism.

The guide sleeve is provided with a main shaft and an eccentric block, the main shaft is provided with a bearing, and the eccentric block is fixed on the bearing;

The guide sleeve is provided with a drilling fluid flow channel, at least three first flow channels leading to the driving mechanism, and at least three second flow channels leading to the outside of the guide sleeve;

The bearing is also provided with a valve structure, which can drive the valve structure to rotate when the eccentric block rotates. The part of the valve structure located on the side where the eccentric block is located can make the first flow channel and the second flow channel on this side lead to the drilling fluid flow channel. Through communication, the part of the valve structure on the side opposite to the eccentric block can close the second flow channel on this side, so that only the first flow channel communicates with the drilling fluid flow channel.

Preferably, the valve structure includes an eccentric ring arranged on the bearing, which rotates together with the eccentric block around the main shaft;

The eccentric ring is provided with a first opening on the side away from the eccentric block, the first opening can conduct the drilling fluid flow channel with the first flow channel on this side, and the eccentric ring wall at the lower part of the first opening can block the second flow channel Conduction with the drilling fluid flow channel;

The eccentric ring is provided with a second opening on the side where the eccentric block is located, and the second opening can conduct the drilling fluid flow channel with the first flow channel and the second flow channel on the side at the same time.

Preferably, the guide structure includes a guide block, and the driving mechanism can make the guide block move radially and telescopically along the guide sleeve.

Preferably, the drive mechanism includes a base arranged at the lower part of the guide sleeve, a piston chamber is provided on the side of the base, and a piston capable of radially moving along the guide sleeve is provided in the piston chamber, and the piston can be pushed when moving away from the base. In the guide block, the piston cavity is connected to the first flow channel, and the end of the first flow channel away from the piston cavity is connected to the drilling fluid flow channel. One end of the second flow channel is connected to the drilling fluid flow channel, and the other end is connected to the outside of the guide sleeve. .

Preferably, the valve structure conducts three first flow passages on the side opposite to where the eccentric block is located, so that the three guide blocks protrude.

Preferably, the guide blocks include 4 first guide blocks and 4 second guide blocks, the first guide blocks and the second guide blocks are distributed at intervals along the circumference of the guide sleeve, the first guide blocks and the second The positions of the guide blocks are mutually staggered, so that each first guide block forms a triangular distribution with two adjacent second guide blocks.

Preferably, the first guide blocks and the second guide blocks are equally spaced along the circumference of the guide sleeve.

Preferably, the bearing includes an upper bearing and a lower bearing, the upper end of the eccentric block is fixed on the upper bearing, the lower end of the eccentric block is fixed on the lower bearing, and the eccentric ring is fixed on the lower part of the lower bearing.

The mechanical static pushing automatic vertical drilling system provided by the present invention has the following beneficial effects:

(1) Using the eccentric block and the eccentric ring to control the expansion and contraction of the guide block only involves the mechanical structure. Compared with electronic devices such as gyroscopes and gravity accelerometers, it is not affected by downhole temperature.

(2) It adopts the principle of dynamic push-and-push automatic vertical drilling control, but uses the difference between the inside and outside of the drilling fluid as the power source, reduces the structural components of the system, and is suitable for small-diameter automatic vertical drilling operations;

(3) The guide actuator adopts the distributed design of 8 guide blocks, which increases the thrust and improves the control accuracy. When the guide blocks are pushed out, a three-point support structure is formed to improve the stability.

Description of drawings

Fig. 1 is the main cross-sectional view of the mechanical static pushing automatic vertical drilling system provided by the present invention;

Fig. 2 is a partially enlarged schematic diagram of the driving mechanism and valve structure of the mechanical static pushing automatic vertical drilling system;

Fig. 3 is a schematic diagram of a partial three-dimensional structure of the base part of the guide structure;

Fig. 4 is the three-dimensional structure schematic diagram of eccentric ring;

Fig. 5 is a side expanded distribution diagram of the guide block.

In the picture:

1. Guide sleeve 2. Drill pipe 3. Drilling fluid channel 4. Upper bearing 5. Lower bearing 6. Eccentric block 7. Base 8. Guide block 9. Piston cavity 10. Piston 11. First flow channel 12. Second flow Road 13. Eccentric ring 81. First guide block 82. Second guide block 131. First opening 132. Second opening

detailed description

In order to enable those skilled in the art to better understand the solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Explanation of terms:

Gravity high side and gravity low side: On the plane composed of the instrument axis direction line and the gravity vertical line, the side where the instrument is located is the gravity high side, and the difference of 180° is the gravity low side.

Please refer to Figures 1-4, a mechanical static pushing automatic vertical drilling system provided by the present invention includes a guide sleeve 1, a drill pipe 2 is arranged inside the guide sleeve 1, the lower end of the drill pipe 2 is connected to a drill bit, and the guide sleeve 1 is outside It is relatively stationary and does not rotate with the drill pipe 2. A drilling fluid channel 3 is arranged inside the guide sleeve 1 for circulating the drilling fluid of the drilling system. With the drill pipe 2 as the main shaft, upper and lower bearings 4 and 5 are sleeved on the upper and lower parts of the main shaft respectively. An eccentric block 6 is arranged between the main shaft and the inner wall of the guide sleeve 1, and the two ends of the eccentric block 6 are respectively fixed on the upper bearing 4 and the inner wall of the guide sleeve 1. On the lower bearing 5, when the drilling system is tilted, the eccentric block 6 can take the main shaft (drill pipe 2) as the axis, rotate and slide along the inner wall of the guide sleeve 1 to the low side of gravity.

A guide structure is provided at the lower end of the guide sleeve 1. The guide structure includes a columnar base 7 as a whole. A plurality of guide blocks 8 are distributed along the circumference of the base 7 outside the base 7. The base 7 is provided with a drive guide block 8 along the guide. The drive mechanism for the radial telescopic movement of the sleeve 1 is also provided with an opening corresponding to the position of the guide block 8 on the guide sleeve 1, so that the guide block 8 can protrude from the opening. The quantity of guide block 8 in the present embodiment is 8, is divided into two groups, each group has 4, and each guide block in the first group of guide blocks is called first guide block 81, each guide block in the second group of guide blocks. The block is called the second guide block 82 . The first set of guide blocks is distributed along the circumference of the base at equal intervals, and the second set of guide blocks is located at the lower part of the first set of guide blocks, and is also distributed along the base at equal intervals in the circumferential direction, but each guide in the second set of guides The positions of the blocks are spaced apart from those of the first group of guide blocks, so that each guide block of the first group of guide blocks can form a triangular distribution with the guide blocks of its adjacent second group of guide blocks.

The driving mechanism for driving the guide block 8 includes a piston chamber 9 formed by recessing from the side of the base, and the piston chamber 9 is provided with a piston 10, the number and position of which are corresponding to each guide block 8, so as to push each guide block 8, the guide block 8 A return spring (not shown in the figure) is correspondingly arranged inside, and one end of each piston 10 away from the guide block 8 is connected to a first flow channel 11 . The end of the first flow channel 11 away from the piston cavity 9 leads to the drilling fluid flow channel 3 . A second flow channel 12 is also provided in the guide sleeve 1 , one end of the second flow channel 12 communicates with the drilling fluid flow channel 3 , and the other end communicates with the outside of the guide sleeve 1 .

An eccentric ring 13 is fixedly connected to the lower end of the lower bearing 5 so that the eccentric ring 13 rotates together with the eccentric block 6 . The eccentric ring 13 is provided with a first opening 131 on the ring wall of the side away from the eccentric block 6. The first opening 131 is in the shape of a bar, which can conduct the drilling fluid flow channel 3 with the first flow channel 11 on this side, and the second opening 131 is in the shape of a bar. The ring wall of the eccentric ring 13 at the bottom of the opening 131 can block the conduction between the second flow channel 12 on this side and the drilling fluid flow channel 3; the eccentric ring 13 is provided with a second opening 132 on the ring wall of the side where the eccentric block 6 is located , the second opening 132 can simultaneously connect the drilling fluid flow channel 3 with the first flow channel 11 and the second flow channel 12 on this side. In this way, when the eccentric block 6 rotates to the low side of gravity, the ring wall of the eccentric ring 13 on the high side of gravity can communicate with the first flow channel 11 of the side and the drilling fluid flow channel 3, while the second flow channel 12 is blocked, and drilling The liquid 3 flows into the piston cavity 9 through the first flow channel 11, and pushes the piston 10 and then pushes the guide block 8 out. The ring wall of the eccentric ring 13 on the low side of gravity can communicate with the drilling fluid flow channel 3 on the first flow channel 11 and the second flow channel 12 at the same time. The pressure is relieved through the second flow channel 12, so that the original protruding guide block 8 is reset under the action of the return spring.

When working, the guide sleeve 1 and the drill bit are drilled with the entire drilling system. When the drilling tool is inclined, the eccentric block 6 rotates and slides to the low side of gravity. At this time, the first opening 131 of the eccentric ring 13 is located on the high side of gravity, which can cut off The second flow channel 12 communicates with the drilling fluid flow channel 3 so that the first flow channel 11 communicates with the drilling fluid flow channel 3 . The drilling fluid automatically flows into the three first flow channels 11 located on the high side of gravity, one of which is connected to the piston chamber 9 corresponding to the first guide block 81, and the other two first flow channels are connected to the piston chamber 9 adjacent to the first guide block 81. The piston cavity corresponding to the two second guide blocks 82, through the piston 10 in the piston cavity 9, pushes a first guide block 81 on the high side of gravity and two second guide blocks 82 adjacent to it, forming a triangular support structure supported in the well. For the inner wall, because the triangular support structure has a large support surface, the coverage of the inner wall of the well is also large, the effect of correcting the well deviation is more accurate and comprehensive, and the triangular support structure is also more stable and reliable. At this time, the second opening 132 of the eccentric ring 13 is located on the low side of gravity, which can make the first flow channel 11 conduct with the drilling fluid flow channel 3, and also make the drilling fluid flow channel 3 conduct with the second flow channel 12. Whether the drilling fluid on this side is in the drilling fluid flow channel 3 or the first flow channel 11, it will flow out of the guide sleeve 1 along the second flow channel 12 to release pressure due to the internal and external pressure difference, so that the guide block 8 on this side can be retracted. and remain indented.

The mechanical static pushing automatic vertical drilling system provided by the present invention has been introduced in detail above. In this paper, specific examples are used to illustrate the principles and implementation modes of the present invention, and the descriptions of the above embodiments are only used to help understand the core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims (5)

1. a kind of mechanical static backup automatic vertical drilling system, including guide sleeve, the bottom of guide sleeve are provided with guide frame, Guide frame is driven by drive mechanism, it is characterised in that is provided with main shaft and eccentric block in the guide sleeve, is arranged with main shaft Bearing, eccentric block are fixed on bearing；

Drilling fluid runner, at least three first flows for being conducted to drive mechanism and at least three conductings are provided with guide sleeve Second flow channel outside to guide sleeve；

Valve mechanism is additionally provided with the bearing, eccentric block can drive valve mechanism to rotate when rotating, and valve mechanism is positioned at bias The part of block side can be such that the first flow of the side, second flow channel is turned on drilling fluid runner, valve mechanism with partially The part of heart block opposite side can close the second flow channel of the side, only make first flow and drilling fluid flow passage；

The guide frame includes guide pad, and drive mechanism can be such that guide pad is moved along the radial expansion of guide sleeve；It is described Drive mechanism includes being arranged on the base of guide sleeve bottom, and the side of base is provided with plunger shaft, provided with can be along in plunger shaft The piston that guide sleeve moves radially, piston can promote the guide pad, plunger shaft connection when being moved to the direction away from base The first flow, the one end of first flow away from plunger shaft and the drilling fluid flow passage, second flow channel one end is communicated to Drilling fluid runner, the other end are communicated to outside guide sleeve；Opposite side of the valve mechanism in eccentric block position turns on Three first flows, so that three guide pads stretch out.

A kind of 2. tool formula static state backup automatic vertical drilling system according to claim 1, it is characterised in that the valve Structure includes an eccentric hoop being arranged on the bearing, is together rotated around main shaft with eccentric block；

Eccentric hoop is provided with the first opening in the side away from eccentric block, and the first opening can be by the first of drilling fluid runner and the side Runner turns on, and the eccentric hoop ring wall of the first lower opening portion can block the conducting of second flow channel and drilling fluid runner；

Eccentric hoop is provided with the second opening in eccentric block side, and the second opening can be by the first-class of drilling fluid runner and the side Road and second flow channel simultaneously turn on.

3. a kind of mechanical static backup automatic vertical drilling system according to claim 1, it is characterised in that described to lead Include the circumference of 4 the first guide pads and 4 the second guide pads, the first guide pad and the second guide pad each along guide sleeve to block In being spaced apart, the position of the first guide pad and the second guide pad is mutually staggered, make that each first guide pad is adjacent thereto two Individual second guide pad forms Triangle-Profile.

4. a kind of mechanical static backup automatic vertical drilling system according to claim 3, it is characterised in that described the One guide pad and the second guide pad each along guide sleeve circumference in being spacedly distributed.

A kind of 5. mechanical static backup automatic vertical drilling system according to claim 2, it is characterised in that the axle Contract and include upper bearing (metal) and lower bearing, the upper end of the eccentric block is fixed on upper bearing (metal), and the lower end of eccentric block is fixed on lower axle Hold, the eccentric hoop is fixed on the bottom of lower bearing.