阅读说明：本技术 一种井下压力平衡装置 (Underground pressure balancing device ) 是由 耿淦 顾鹏 时好振 于 2021-04-16 设计创作，主要内容包括：本发明涉及压力平衡技术领域,提供一种井下压力平衡装置,其中所述的钻铤内壁安装内筒,钻铤一端设公螺纹,另一端设母螺纹；钻铤内远离公螺纹一端设有过孔端盖,过孔端盖与内筒间安装止动环；过孔端盖顶部且活塞底部为钻井液室,活塞与滑块连杆机构间安装有碟簧组；顶杆一端与短连杆一端连接,短连杆另一端与推力杆一端连接,推力杆另一端与扶正块一端铰接,扶正块另一端与支撑杆一端铰接,支撑杆另一端与钻铤连接；优点为：本发明将可变的钻井液压力转换成碟簧组的压缩力,根据钻井液压力的变化调整扶正块的伸缩,将钻井液压力近乎恒定,同时可扶正钻具,对钻井轨迹纠斜；液压系统是纯机械,不包括电子和电气控制的组件,可靠性更高。(The invention relates to the technical field of pressure balance and provides a downhole pressure balance device, wherein an inner cylinder is arranged on the inner wall of a drill collar, male threads are arranged at one end of the drill collar, and female threads are arranged at the other end of the drill collar; a through hole end cover is arranged at one end, far away from the male thread, in the drill collar, and a stop ring is arranged between the through hole end cover and the inner cylinder; a drilling fluid chamber is arranged at the top of the via hole end cover and the bottom of the piston, and a disc spring group is arranged between the piston and the sliding block connecting rod mechanism; one end of the ejector rod is connected with one end of a short connecting rod, the other end of the short connecting rod is connected with one end of a thrust rod, the other end of the thrust rod is hinged with one end of a centering block, the other end of the centering block is hinged with one end of a supporting rod, and the other end of the supporting rod is connected with a drill collar; has the advantages that: the invention converts the variable drilling fluid pressure into the compression force of the disc spring group, adjusts the extension of the centralizing block according to the change of the drilling fluid pressure, ensures that the drilling fluid pressure is nearly constant, and simultaneously can centralize a drilling tool to correct the drilling track; the hydraulic system is purely mechanical, does not comprise components controlled electronically and electrically, and has higher reliability.)

1. The utility model provides a pressure balancing unit in pit, includes drill collar, drilling fluid chamber and slider link mechanism, its characterized in that: the drill collar is hollow, an inner cylinder is mounted on the inner wall of the drill collar, the inner cylinder is a water hole part, a male thread is arranged at one end of the drill collar and connected with a drilling tool assembly, a female thread is arranged at the other end of the drill collar and connected with a drill bit; a through hole end cover is arranged at one end, far away from the male thread, in the drill collar and fixed on the drill collar through the thread, a stop ring is arranged between the through hole end cover and the inner cylinder, and the inner cylinder and the stop ring are tightly pressed on the drill collar through the through hole end cover; the drilling fluid chamber is arranged at the top of the via hole end cover and the bottom of the piston, a shearing pin is arranged on one side of the drilling fluid chamber and on the wall of the drill collar, one end of the shearing pin extends into the piston, sealing rings are arranged on the piston and the inner cylinder, and a disc spring group is arranged between the piston and the slider connecting rod mechanism; the slide block connecting rod mechanism comprises a top rod, a short connecting rod, a thrust rod, a centering block and a supporting rod, wherein one end of the top rod is connected with one end of the short connecting rod through a hinge, the other end of the short connecting rod is connected with one end of the thrust rod through a hinge, the other end of the thrust rod is hinged with one end of the centering block through a pin and a hinge, the other end of the centering block is hinged with one end of the supporting rod through a pin and a hinge, and the other end of the supporting rod is connected with the drill collar through a hinge.

2. A downhole pressure equalizing device as in claim 1, wherein: 4 groups of sliding block link mechanisms are uniformly distributed in the peripheral direction of the outer part of the drill collar.

3. A downhole pressure equalisation device according to claim 1 or 2, wherein: the slide block connecting rod mechanism can radially extend to contact with the well wall.

4. A downhole pressure equalizing device as in claim 1, wherein: the sliding block connecting rod mechanism and the disc spring group are exposed in mud outside the drill collar.

5. A downhole pressure equalizing device as in claim 1, wherein: the inner cylinder isolates drilling fluid in the drill collar from drilling fluid outside the drill collar.

6. A downhole pressure equalizing device as in claim 1, wherein: the drilling fluid chamber is annular.

7. A downhole pressure equalizing device as in claim 1, wherein: the outer surface of the righting block is provided with a wear-resistant layer or a wear-resistant belt.

8. A downhole pressure equalizing device as in claim 1, wherein: the hinge is a cylindrical hinge.

Technical Field

The invention relates to the technical field of pressure balance, in particular to an underground pressure balance device.

Background

With the continuous progress of drilling technology, various pressure balancing devices are widely used in the drilling industry. A common pressure balancing device utilizes the pressure difference between the drilling fluid in the drilling assembly and the drilling fluid in the borehole annulus to achieve the function of an instrument; the pressure differential may also be used to adjust the wings of the centralizer to drill in accordance with a predetermined trajectory. However, parameters such as the size of the well bore, the displacement of the drilling fluid, the viscosity, the drilling rate, the size of the drill bit nozzle, and the distance between the hydraulic system and the drill bit all affect the accuracy of the pressure difference; therefore, under different well conditions, the drilling parameters have great difference, so that the pressure difference is greatly changed, the accuracy of the pressure control of the drilling fluid is influenced, and the reliability of the instrument is greatly reduced. In addition, the conventional pressure balancing device is correspondingly set according to the current parameters such as displacement, viscosity and the like before the well is lowered, and if drilling parameters are changed, the pump needs to be stopped to adjust the pressure balancing device.

As a ready-to-use, thermally heatable rotary guide tool, pressure-equalizing devices are also used, which are relatively complex. Before the well is put in, the track data of the well is preset in the control circuit, the pressure balancing device provides power for the support wing plates during the well drilling, the magnitude of the hydraulic expenditure of 3 support wing plates is controlled by the underground control circuit, and the purpose of controlling the magnitude and the direction of the resultant biasing force is achieved. Therefore, the direction of the well track can be adjusted, and the size of the build-up rate can also be adjusted, so that the control of the guided drilling is realized. While pressure balancing devices have found reliable application in rotary steerable tools, due to their complexity, production and maintenance costs tend to be high. Thus, conventional oil and gas wells are not suitable.

Disclosure of Invention

The invention aims to solve the defects of the prior art and provide a downhole pressure balancing device.

The new technical scheme of the invention is as follows: a downhole pressure balancing device comprises a drill collar, a drilling fluid chamber and a slider link mechanism, wherein the drill collar is hollow, an inner cylinder is arranged on the inner wall of the drill collar and is a water hole part, a male thread is arranged at one end of the drill collar and is connected with a drilling tool assembly, a female thread is arranged at the other end of the drill collar and is connected with a drill bit; a through hole end cover is arranged at one end, far away from the male thread, in the drill collar and fixed on the drill collar through the thread, a stop ring is arranged between the through hole end cover and the inner cylinder, and the inner cylinder and the stop ring are tightly pressed on the drill collar through the through hole end cover; the drilling fluid chamber is arranged at the top of the via hole end cover and the bottom of the piston, a shearing pin is arranged on one side of the drilling fluid chamber and on the wall of the drill collar, one end of the shearing pin extends into the piston, sealing rings are arranged on the piston and the inner cylinder, and a disc spring group is arranged between the piston and the slider connecting rod mechanism; the slide block connecting rod mechanism comprises a top rod, a short connecting rod, a thrust rod, a centering block and a supporting rod, wherein one end of the top rod is connected with one end of the short connecting rod through a hinge, the other end of the short connecting rod is connected with one end of the thrust rod through a hinge, the other end of the thrust rod is hinged with one end of the centering block through a pin and a hinge, the other end of the centering block is hinged with one end of the supporting rod through a pin and a hinge, and the other end of the supporting rod is connected with the drill collar through a hinge.

4 groups of sliding block link mechanisms are uniformly distributed in the peripheral direction of the outer part of the drill collar.

The slide block connecting rod mechanism can radially extend to contact with the well wall.

The sliding block connecting rod mechanism and the disc spring group are exposed in mud outside the drill collar.

The inner cylinder isolates drilling fluid in the drill collar from drilling fluid outside the drill collar.

The drilling fluid chamber is annular.

The outer surface of the righting block is provided with a wear-resistant layer or a wear-resistant belt.

The hinge is a cylindrical hinge.

The invention has the beneficial effects that: the invention converts the variable drilling fluid pressure into the compression force of the disc spring group, adjusts the extension of the centralizing block according to the change of the drilling fluid pressure, ensures that the drilling fluid pressure is nearly constant, and simultaneously can centralize a drilling tool to correct the drilling track; the hydraulic system is purely mechanical, does not comprise components controlled electronically and electrically, and has higher reliability.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural diagram of the working state of the present invention.

Fig. 3 is an external structural view of the present invention.

Wherein: 1. the drill collar comprises a drill collar body 2, a centering block 3, a support rod 4, a thrust rod 5, a short connecting rod 6, a push rod 7, a disc spring group 8, a piston 9, an inner cylinder 10, a shearing pin 11, a through hole end cover 12, a stop ring 13 and a drilling fluid chamber.

Detailed Description

The invention will be further described with reference to the accompanying drawings.

A downhole pressure balancing device comprises a drill collar 1, a drilling fluid chamber 13 and a slider link mechanism, wherein the drill collar 1 is hollow, an inner cylinder 9 is arranged on the inner wall of the drill collar 1, the inner cylinder 9 is a water hole part, one end of the drill collar 1 is provided with a male thread, the male thread is connected with a drilling tool assembly, the other end of the drill collar 1 is provided with a female thread, and the female thread is connected with a drill bit; a via hole end cover 11 is arranged at one end, far away from the male thread, in the drill collar 1, the via hole end cover 11 is fixed on the drill collar 1 through threads, a stop ring 12 is arranged between the via hole end cover 11 and the inner cylinder 9, and the inner cylinder 9 and the stop ring 12 are tightly pressed on the drill collar 1 through the via hole end cover 11; the drilling fluid chamber 13 is arranged at the top of the via hole end cover 11 and the bottom of the piston 8, a shearing pin 10 is arranged on one side of the drilling fluid chamber 13 and on the wall of the drill collar 1, one end of the shearing pin 10 extends into the piston 8, sealing rings are arranged on the piston 8 and the inner cylinder 9, and a disc spring group 7 is arranged between the piston 8 and the slider link mechanism; the slider link mechanism comprises a top rod 6, a short connecting rod 5, a thrust rod 4, a centering block 2 and a supporting rod 3, one end of the top rod 6 is connected with one end of the short connecting rod 5 through a hinge, the other end of the short connecting rod 5 is connected with one end of the thrust rod 4 through a hinge, the other end of the thrust rod 4 is hinged with one end of the centering block 2 through a pin and a hinge, the other end of the centering block 2 is hinged with one end of the supporting rod 3 through a pin and a hinge, and the other end of the supporting rod 3 is connected with the drill collar 1 through a hinge.

4 groups of sliding block link mechanisms are uniformly distributed in the peripheral direction of the outside of the drill collar 1.

The slide block connecting rod mechanism can radially extend to contact with the well wall.

The slide block link mechanism and the disc spring group 7 are exposed in mud outside the drill collar 1.

The inner cylinder 9 isolates the drilling fluid in the drill collar 1 from the drilling fluid outside the drill collar 1.

The drilling fluid chamber 13 is annular.

And the outer surface of the righting block 2 is provided with a wear-resistant layer or a wear-resistant belt.

The hinge is a cylindrical hinge.

The utility model provides a pressure balancing unit in pit, under the state of opening the pump, well drilling fluid pressure increases in the well, drilling fluid enters into well drilling fluid chamber 13 through via hole end cover 11 in, drilling fluid promotes piston 8, the motion of piston 8 is cut shear pin 10, piston 8 continues to move compression dish spring group 7, piston 8 and then promote the action of slider link mechanism, make and right piece 2 open, right piece 2 progressively is close the wall of a well, reach the effect of balanced intraocular pressure effect promptly, simultaneously through the contact of right piece 2 with the wall of a well, can right the drilling tool, play the effect of rectifying to the drilling track.