CN216691004U

CN216691004U - Constant-pressure constant-torque tool for well drilling

Info

Publication number: CN216691004U
Application number: CN202122666287.XU
Authority: CN
Inventors: 彭文玥; 石擎天; 严佳玲; 许毅; 陈俊; 李凤顺; 邓勤
Original assignee: Chengdu Asberi Technology Co ltd
Current assignee: Chengdu Asberi Technology Co ltd
Priority date: 2021-11-03
Filing date: 2021-11-03
Publication date: 2022-06-07
Anticipated expiration: 2031-11-03

Abstract

The utility model discloses a constant-pressure constant-torque tool for fluid drilling, which comprises an upper joint, an upper shell, a middle shell, a lower joint, a compensation joint, a mandrel, a limiting retaining ring, a piston, a nut, a disc spring group I, a disc spring group II and a disc spring group III, wherein the mandrel is provided with an inner through hole, a mandrel bypass hole and a limiting step, the upper shell is internally provided with the disc spring group I and the disc spring group II, the compensation joint is internally provided with the disc spring group III, the middle shell is internally provided with a multi-head thread groove and an oil injection hole, the lower joint is externally provided with a multi-head thread groove, the lower shell is provided with a combined sealing groove and an oil injection hole, the piston is provided with a combined sealing groove, the radial position and the axial position of the lower joint are changed by meshing of the multi-head thread groove of the middle shell and the multi-head thread groove of the lower joint, and the energy storage function of the disc spring group is combined to achieve the purpose of constant pressure and constant torque, and the tool has a compact structure, the drilling tool has strong functions, can protect different drilling tools according to different installation positions, and achieves the purpose of stable drilling.

Description

Constant-pressure constant-torque tool for well drilling

Technical Field

The utility model belongs to the technical field of downhole tools in oil and gas drilling engineering, and particularly relates to a constant-pressure constant-torque tool for preventing drill sticking and reducing stick-slip in ultra-deep wells and extended-reach wells.

Background

With the continuous development of the industry in China, the required exploitation amount of petroleum and natural gas is increasing day by day, the situation leads to the exhaustion of shallow layer oil gas resources, and in order to relieve the shortage problem of petroleum resources, petroleum exploitation is started to be carried out to deep wells and ultra-deep wells. However, in the process of drilling ultra-deep wells, extended reach wells and horizontal wells, when a continuous oil pipe works, particularly when a soft and hard staggered stratum is encountered, a PDC drill bit is easy to slip during drilling, which causes frequent tripping and torsional vibration of the drill bit and a drilling tool, which causes tooth breakage and damage of the drill bit, signal loss of an MWD logging instrument and damage of a downhole drilling tool assembly, so that the mechanical drilling speed and the rock breaking efficiency of the drill bit are reduced, and the drilling cost is increased. At present, most drilling sites adopt a tripping mode to solve the phenomena of drilling holding and sticking, and the drilling efficiency is greatly reduced.

Based on this, in order to prevent the drill bit drilling sticking, suppress brill and torsional vibration phenomenon, improve drilling efficiency, this paper provides a constant voltage and torque instrument that solves above problem.

Disclosure of Invention

The utility model aims to provide a constant-pressure and constant-torque tool which utilizes a disc spring set to absorb vibration energy in the axial direction and the radial direction so as to realize constant bit pressure and torque. The design of the large-lead multi-start thread can quickly transmit axial and radial vibration loads generated when the drill bit is drilled in a stratum to the disc spring group for absorption, and the purpose of constant pressure and constant torque is achieved.

The purpose of the utility model is realized by the following technical scheme:

a constant-pressure and constant-torque tool for well drilling comprises an upper shell, an upper joint connected with the upper shell through threads, a middle shell connected with the upper shell through threads, a mandrel connected with the upper joint through threads, a lower shell connected with the middle shell through threads, a piston connected with the lower joint through threads, a compensation joint connected with the lower joint through threads, a nut connected with the mandrel through threads, a disc spring group I and a disc spring group II which are arranged between the upper joint and the mandrel, a disc spring group III arranged between the compensation joint and the mandrel, a limit retaining ring arranged between the disc spring group I and the disc spring group II, an inner through hole, a mandrel bypass hole and a limit step which are arranged on the mandrel, a multi-head thread groove and an oil injection hole which are arranged inside the middle shell, a multi-head thread groove which is arranged outside the lower joint, a combined seal groove and an oil injection hole which are arranged inside the lower shell, and a combined seal groove which is arranged outside the piston, the lower joint can realize the switching of radial position and axial position through the meshing of multi-thread groove.

Preferably, the mandrel is provided with a limiting step, and the compression amount of the disc spring group I can be limited by matching with the limiting retaining ring, so that the disc spring group I is prevented from being excessively compressed.

Preferably, the multi-thread groove of the middle shell and the multi-thread groove of the lower joint have a helix angle of 20 to 40 °.

Preferably, the stiffness coefficient of the disc spring group II is 2-3 times of that of the disc spring group I, and the stiffness coefficient of the disc spring group III is the same as that of the disc spring group I.

Preferably, the mandrel and the upper joint are connected together through threads, and the relative rotation of the mandrel and the upper joint in the circumferential direction is prevented through a set screw.

Preferably, the piston and the lower joint are screwed together and prevented from relative rotation in the circumferential direction by a set screw.

Preferably, the nut and the mandrel are connected together through threads, the compression amount of the disc spring group III is adjusted through rotating the nut, and the relative rotation in the circumferential direction is prevented through the fastening screw after the adjustment is finished.

Compared with the prior art, the utility model has the beneficial effects that:

(1) the compression amount of the disc spring group III is adjusted by rotating the nut, so that the weight of a drill string connected to the lower part of the tool can be balanced, when the drill bit is connected and goes down to the well bottom together, the soft landing of the drill bit can be realized, and the instantaneous impact damage of the drill bit contacting the well bottom is avoided;

(2) when a drill bit at the bottom of a well is stuck or is blocked, the torque at the bottom of the well can be suddenly increased, the multi-head thread part of the lower connector rotates relatively, the disc spring group I and the disc spring group II contract rapidly, the drill string is shortened, the drill bit is gradually lifted away from the bottom of the well, the torque is gradually reduced, after the torque is reduced to a certain degree, the compression energy of the disc spring is released, the lower connector is driven to increase the torque to rotate, and finally the purpose of constant pressure and constant torque is achieved;

(3) the axial contraction energy storage capacity of the disc spring group is combined with the pressure and torsion transducing force of the multi-start thread, so that the axial vibration and the torsion vibration of a drill column can be reduced

(4) The design of different rigidity coefficients of the disc spring group I and the disc spring group II can realize rapid contraction aiming at different torques.

Description of the drawings:

FIG. 1 is a schematic structural view of the present invention;

in the figure: 1. the sealing structure comprises an upper shell, 2 parts of an upper joint, 3 parts of a middle shell, 4 parts of a mandrel, 5 parts of a lower shell, 6 parts of a lower joint, 7 parts of a piston, 8 parts of a compensation joint, 9 parts of a nut, 10 parts of a disc spring group I, 11 parts of a disc spring group II, 12 parts of a disc spring group III, 13 parts of a limit retaining ring, 31 parts of a multi-head thread groove of the middle shell, 32 parts of an oil filling hole of the middle shell, 41 parts of an inner through hole of the mandrel, 42 parts of a bypass hole of the mandrel, 43 parts of a limiting step of the mandrel, 51 parts of a combined sealing groove of the lower shell, 52 parts of the oil filling hole of the lower shell, 61 parts of the multi-head thread groove of the lower joint, and 71 parts of a combined sealing groove of the piston.

FIG. 2 is a cross-sectional view of the housing of the present invention;

in the figure: 3. middle casing, 31, middle casing multi-thread groove, 32, middle casing oil filler point.

FIG. 3 is a cross-sectional view of the lower fitting of the present invention;

in the figure: 6. and the lower joint 61 is a multi-head thread groove of the lower joint.

The specific implementation mode is as follows:

the following non-limiting examples serve to illustrate the utility model.

Example (b):

as shown in fig. 1 to 3, a constant-pressure constant-torque tool for drilling comprises an upper shell (1), an upper joint (2) connected with the upper shell (1) through threads, a middle shell (3) connected with the upper shell (1) through threads, a mandrel (4) connected with the upper joint (2) through threads, a lower shell (5) connected with the middle shell (3) through threads, a piston (7) connected with a lower joint (6) through threads, a compensation joint (8) connected with the lower joint through threads, a nut (9) connected with the mandrel through threads, a disc spring group I (10) and a disc spring group II (11) arranged between the upper shell (1) and the mandrel (4), a disc spring group III (12) arranged between the lower joint (6) and the mandrel (4), and a limit stop ring (13) arranged between the disc spring group I (10) and the disc spring group II (11), wherein an inner through hole (41) and a disc spring group II (11) are formed in the mandrel (4), Dabber by-pass hole (42) and spacing step (43), multi-thread groove (31) and oil filler point (32) have been seted up to well casing (3) inside, multi-thread groove (61) have been seted up to lower clutch (6) outside, combination seal groove (51) and oil filler point (52) have been seted up to lower casing (5) inside, combination seal groove (71) have been seted up to piston (7) outside, the switching of radial position and axial position is realized in the meshing of multi-thread groove (61) on lower clutch (6) accessible lower clutch (6) and multi-thread groove (31) on well casing (3).

The constant-pressure constant-torque drilling device described in the embodiment mainly comprises two working modes: a drill-down mode and a normal drilling mode.

In a drilling mode, a tool is connected into a drilling tool assembly, the tool to be protected, such as a rotary steering tool, an MWD (measurement while drilling), a screw motor, a drill bit and the like, is connected to the lower portion of the tool assembly, the weight of a lower drilling tool is calculated, the compression amount of a disc spring group III is adjusted according to the weight of the lower drilling tool, so that the generated reset force is basically balanced with the weight of the lower drilling tool, at the moment when the drilling tool assembly is lowered into and contacted with a well bottom, the impact force of the lower drilling tool on the well bottom is basically zero, and when the drilling tool assembly continues to descend, a disc spring group I and a disc spring group II are compressed.

In a normal drilling mode, a disc spring group I and a disc spring group II are in a compressed state, in order to protect the disc spring group I from exceeding the maximum load, a limiting step is arranged on a mandrel, the maximum compression amount of the disc spring group I is protected through a limiting retaining ring, the rest load is borne by the disc spring group II, when a drill bit starts to contact with rocks to break the rocks, the drilling pressure applied to the drill bit is connected through the threads of an upper connector, an upper shell and a middle shell, and is transmitted to a lower connector through the multi-start thread meshing of the middle shell and the lower connector, so that the lower connector rotates and moves in the direction of the upper connector to compress the disc spring group I and the disc spring group II, and finally is transmitted to a lower drilling tool through a compensation connector and finally transmitted to the drill bit; in the clockwise rotation process of the shell of the drilling tool, the torque is transmitted to the lower joint through the multi-thread meshing of the middle shell and the lower joint, if the torque transmitted by the lower joint is converted into an axial force and then is larger than the load force borne by the disc spring group I and the disc spring group II, the lower joint further upwards compresses the disc spring group I and the disc spring group II, finally the torque is transmitted to the lower drilling tool and the drilling bit through the compensation joint to drive the drilling bit to rotate clockwise, and after the drilling pressure and the torque are transmitted to the drilling bit, the drilling bit starts to normally drill; when the drill bit encounters soft and hard staggered strata, hard strata or overlarge drilling pressure, the drill bit has the phenomenon of drill bit jamming or larger stick-slip, the received reaction torque is increased, at the moment, the multi-head thread grooves on the middle shell and the lower connector rotate relatively to drive the lower connector, the compensation connector, the lower drilling tool and the drill bit to quickly move upwards to compress the disc spring group I and the disc spring group II, so that the cutting depth of the drill bit is reduced, the reaction torque received by the drill bit is gradually reduced along with the reduction of the cutting depth, when the reaction torque disappears, the axial force stored in the disc spring group I and the disc spring group II is gradually released and transmitted to the lower connector, the axial force is converted into torque through the meshing of the multi-head thread grooves and transmitted to the lower drilling tool and the drill bit to continue normal drilling, and the drill bit does not leave rock stratum all the time in the whole process, in conclusion, the drill bit reaction torque caused by the strata or the drilling pressure is increased, the constant-pressure constant-torque tool can quickly respond and finally achieve the purpose of constant-pressure constant-torque drilling.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A constant pressure and torque tool for well drilling is characterized in that: comprises an upper shell (1), an upper joint (2) connected with the upper shell (1) through threads, a middle shell (3) connected with the upper shell (1) through threads, a mandrel (4) connected with the upper joint (2) through threads, a lower shell (5) connected with the middle shell (3) through threads, a piston (7) connected with a lower joint (6) through threads, a compensation joint (8) connected with the lower joint through threads, a nut (9) connected with the mandrel through threads, a disc spring group I (10) and a disc spring group II (11) are arranged between the upper shell (1) and the mandrel (4), a disc spring group III (12) is arranged between the lower joint (6) and the mandrel (4), and a limit retaining ring (13) arranged between the disc spring group I (10) and the disc spring group II (11), wherein an inner through hole (41), a mandrel hole (42) and a limit step (43) are arranged on the mandrel (4), the multi-thread groove (31) and the oil filler point (32) are formed in the middle shell (3), the multi-thread groove (61) is formed in the outer portion of the lower connector (6), the combined sealing groove (51) and the oil filler point (52) are formed in the inner portion of the lower shell (5), the combined sealing groove (71) is formed in the outer portion of the piston (7), and the multi-thread groove (61) in the lower connector (6) can be meshed with the multi-thread groove (31) in the middle shell (3) to achieve changes of radial positions and axial positions.

2. The constant pressure and torque tool for well drilling according to claim 1, wherein: the limiting step (43) is formed in the mandrel (4), and the compression amount of the disc spring group I (10) can be limited by matching with the limiting retaining ring (13), so that the disc spring group I (10) is prevented from being excessively compressed.

3. The constant pressure and torque tool for well drilling according to claim 1, wherein: the multi-thread groove (31) of the middle shell (3) and the multi-thread groove (61) of the lower joint (6) have a helix angle of 20-40 degrees.

4. The constant pressure and torque tool for well drilling according to claim 1, wherein: the rigidity coefficient of the disc spring group II (11) is 2-3 times that of the disc spring group I (10), and the rigidity coefficient of the disc spring group III (12) is the same as that of the disc spring group I (10).

5. The constant pressure and torque tool for well drilling according to claim 1, wherein: the mandrel (4) is connected with the upper joint (2) through threads, and the relative rotation of the mandrel and the upper joint in the circumferential direction is prevented through a set screw.

6. The constant-pressure and constant-torque tool for drilling according to claim 1, wherein: the piston (7) is connected with the lower joint (6) through threads, and the circumferential relative rotation of the piston and the lower joint is prevented through a set screw.

7. The constant pressure and torque tool for well drilling according to claim 1, wherein: the nut (9) is connected with the mandrel (4) through threads, the compression amount of the disc spring group III (12) is adjusted through rotating the nut (9), and the disc spring group III is prevented from rotating in the circumferential direction through a set screw after the adjustment is finished.