CN110029933A - Based on turbo-driven double speed PDC drill bit - Google Patents

Abstract

The invention discloses a two-speed PDC drill bit driven by a turbine, comprising an upper joint, upper and lower positioning blocks of a turbine shaft, large and small steel balls, turbine blades, an epitaxial large drill bit, a turbine shaft, a guide joint and a Y-shaped sealing ring , the extension of the large drill bit nozzle, the center small drill bit; the assembly sequence is to first install the turbine shaft on the turbine blade and the guide joint to form an integral part; the extension of the large drill bit nozzle, the Y-shaped sealing ring, and the lower positioning block of the turbine with small steel balls Put it into the epitaxial large drill bit, put the above integral parts into the epitaxial large drill bit; assemble the central small drill bit on the diversion joint; finally install the large steel ball, the upper positioning block of the turbine, and the upper joint in sequence. The invention drives the inner turbine of the epitaxial large drill bit through drilling fluid, and then drives the center small drill bit, and has the characteristics that the center small drill bit and the epitaxial large drill bit drill at different speeds.

Description

Turbine-driven two-speed PDC bit

technical field

The invention belongs to the field of oil and natural gas exploitation, and particularly relates to the design of a turbine-driven two-speed PDC drill bit.

Background technique

With the deepening of the exploration and development of oil and gas resources, there are more and more deep wells, ultra-deep wells and new oil and gas resource wells, and it is possible to drill into the "three high formations" (high rock hardness, high rock drillability grade, and high rock abrasiveness). In the process of drilling and breaking traditional PDC bits, the low rock breaking efficiency at the core is an important factor restricting the ROP. The main reason for the low rock-breaking efficiency in the core is that the cutting teeth in the core of the wellbore move at a low speed during the rock-breaking process, resulting in the core of the drill bit being "jacked" by the rock during the drilling process. Impact crushing of roller cone bits or rock breaking of PDC bits. This seriously affects the ROP and exploration and development costs in deep hard formations. ROP and service life are two important indicators to measure the performance of the drill bit, and improving the ROP has always been a key issue in drilling engineering. Under the premise of ensuring a certain service life, increasing the ROP is of great significance for increasing the total footage of the drill bit, reducing the number of trips and reducing production costs. Aiming at the problem of low ROP during drilling in deep hard formations, the two-speed PDC bit driven by the turbine of the present invention can use the turbine to drive the small central drill bit to break the rock in the center first, and at the same time use the drill string to drive the epitaxial large drill bit to rapidly drill It can effectively improve the drilling efficiency.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the problem that the core of the traditional PDC bit is "pushed" by the rock during the drilling process mentioned in the background art, resulting in a low ROP, and proposes a two-speed PDC bit driven by a turbine.

The technical scheme of the present invention is: a two-speed PDC drill bit driven by a turbine is composed of an upper joint, a positioning block on the turbine shaft, a large steel ball, a turbine blade, an epitaxial large drill bit, a turbine shaft, a small steel ball, a lower positioning block on the turbine shaft, and a flow guide. The joint is composed of a Y-shaped sealing ring, an extension large drill bit nozzle, and a small central drill bit, and is characterized in that: the assembly sequence is to assemble the turbine blade on the turbine shaft first, and connect the guide joint at the lower end of the turbine shaft by threaded connection to form an integral part; Install the epitaxial large drill nozzle on the epitaxial large drill bit, install a Y-shaped sealing ring in the groove of the epitaxial large drill bit, put the lower positioning block of the turbine into the epitaxial large drill bit, and put small steel balls in the groove of the lower positioning block of the turbine. The above-mentioned integral components are loaded into the epitaxial large drill bit; the central small drill bit is threadedly connected to the other end of the diversion joint; the large steel ball is loaded into the upper end of the turbine shaft, and then the positioning block on the turbine is installed, and the upper joint is connected by thread to complete the assembly.

The turbine-driven two-speed PDC drill bit in the above scheme is characterized in that: the diversion joint is provided with three oblique holes uniformly distributed in the circumferential direction, and the drilling fluid extends from the annulus between the epitaxial large drill bit and the diversion joint, and passes through the diversion joint. The inclined hole enters the diversion joint, and thus enters the small central drill bit, and is ejected from the nozzle of the small central drill bit during drilling. The inclined hole is beneficial to reduce the pressure drop of the drilling fluid.

The turbine-driven two-speed PDC drill bit in the above scheme is characterized in that: there are grooves on the lower positioning block of the turbine and the turbine shaft, and small steel balls are loaded between the two grooves; when drilling, the turbine shaft drives the center small drill bit Rotate to break the rock to reduce the frictional resistance between the positioning block under the turbine and the turbine shaft.

The turbine-driven two-speed PDC drill bit in the above scheme is characterized in that: there are pits on the upper end of the turbine shaft and the positioning block on the turbine, and a large steel ball is installed between the two pits; when drilling, the turbine shaft drives the center The small drill bit rotates to break the rock, reducing the frictional resistance between the positioning block on the turbine and the turbine shaft.

The turbine-driven two-speed PDC drill bit in the above scheme is characterized in that: two Y-shaped sealing rings are designed between the extended large drill bit and the guide joint, and the opening directions of the two Y-shaped sealing rings are opposite, and the upper one faces upwards. , the bottom is downward; it can prevent the drilling fluid from flowing out or flowing in between the epitaxial large drill bit and the diversion joint.

The turbine-driven two-speed PDC drill bit in the above scheme is characterized in that: the upper positioning block of the turbine and the lower positioning block of the turbine are provided with a flow passage; the drilling fluid can push the turbine blades through the upper positioning block of the turbine, thereby driving the turbine shaft to rotate; After that, the drilling fluid can pass through the lower positioning block of the turbine, and part of it is ejected from the nozzle of the extended large drill bit, and the other part enters the small central drill bit through the guide joint and is ejected from the nozzle.

The beneficial effects of the present invention are: (1) the design of the turbine-driven two-speed PDC drill bit is compact and reasonable; (2) the dual-speed drilling function of the central small drill bit and the epitaxial large drill bit can be realized; (3) the mechanical Drilling speed, improve drilling efficiency.

Description of drawings

FIG. 1 is a schematic diagram of the structure of the turbine-driven two-speed PDC drill bit of the present invention.

FIG. 2 is a diagram showing the internal assembly components of FIG. 1 of the present invention.

FIG. 3 is a three-dimensional model diagram of FIG. 1 of the present invention.

FIG. 4 is a three-dimensional view of the lower positioning block of the turbine shaft in FIG. 1 of the present invention.

Explanation of reference numerals: 1. Upper joint, 2. Positioning block on turbine shaft, 3. Large steel ball, 4. Turbine blade, 5. Extended large drill bit, 6. Turbine shaft, 7. Small steel ball, 8. Lower positioning of turbine shaft Block, 9. Diversion joint, 10. Y-shaped sealing ring, 11. Expansion large drill nozzle, 12. Center small drill.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings:

According to the drawings, the two-speed PDC drill bit driven by the turbine is composed of an upper joint (1), a positioning block on the turbine (2), a large steel ball (3), a turbine blade (4), an epitaxial large drill bit (5), and a turbine Shaft (6), small steel ball (7), turbine lower positioning block (8), diversion joint (9), sealing ring (10), extended large drill bit nozzle (11), central small drill bit (12), its features are: Yes: the assembly sequence is to first assemble the turbine blade (4) on the turbine shaft (6), and connect the upper guide joint (9) at the lower end of the turbine shaft (6) by thread to form an integral part; place the turbine lower positioning block (8) ) into the epitaxial large drill bit (5), insert small steel balls (7) into the groove of the lower locating block (8) of the turbine, install the sealing ring (10) in the groove of the epitaxial large drill bit (5), and place the above The integral part is installed into the extended large drill bit (5); the large steel ball (3) is installed on the upper end of the turbine shaft (6), and then the upper positioning block (2) of the turbine is installed, and the upper joint (1) is connected by threads; (5) Install the epitaxial large drill nozzle (11), and the assembly is completed.

The working process of the two-speed PDC bit driven by the turbine: the upper end of the upper joint (1) is connected to the drill string, and the drill string rotates while driving the epitaxial large drill bit (5) to rotate to break the rock; high-pressure drilling fluid is injected from the inside of the drill string, and the drilling fluid passes through The upper joint (1) of the two-speed PDC bit driven by the turbine flows through the positioning block (2) on the turbine shaft to push the turbine blade (4), and then drives the turbine shaft (6) to rotate; The joint (9) is connected, and the diversion joint (9) is connected with the small central drill bit (12); finally the turbine shaft (6) drives the small central drill bit (12) to rotate to break the rock; the drilling fluid continues to flow through the lower positioning block (8) of the turbine , enter the annulus between the large epitaxial drill bit (5) and the diversion joint (9), part of it is ejected from the nozzle (11) of the large epitaxial drill bit, and the other part enters the small central drill bit (12) through the diversion joint (9), It is sprayed from the nozzle to clean the bottom of the well, and the cuttings are carried out from the wellbore for drilling operations.

The diversion joint (9) in the above scheme is provided with three oblique holes uniformly distributed in the circumferential direction, and the drilling fluid enters the diversion through the inclined holes from the annulus between the epitaxial large drill bit (5) and the diversion joint (9). The flow joint (9) enters the central small drill bit (12), and is ejected from the nozzle during drilling, and the inclined hole is beneficial to reduce the pressure drop of the drilling fluid.

The turbine lower positioning block (8) and the turbine shaft (6) in the above scheme have grooves, and small steel balls (7) are loaded between the two grooves; when drilling, the turbine shaft (6) drives the center small drill bit ( 12) Rotate to break the rock to reduce the frictional resistance between the turbine lower positioning block (8) and the turbine shaft (6). There are pits on the upper end of the turbine shaft (6) and the positioning block (2) on the turbine, and a large steel ball (3) is installed between the two pits; when drilling, the turbine shaft (6) drives the small central drill bit (12) Rotating to break the rock reduces the frictional resistance between the positioning block (2) on the turbine and the turbine shaft (6).

Based on the turbine-driven two-speed PDC drill bit, two Y-shaped sealing rings (10) are designed between the extended large drill bit (5) and the guide joint (9), and the opening directions of the two Y-shaped sealing rings (10) are opposite to each other. , the upper part is upward, and the lower part is downward; the drilling fluid can be prevented from flowing out or flowing in between the epitaxial large drill bit (5) and the diversion joint (9).

Based on the turbine-driven two-speed PDC drill bit, the turbine upper positioning block (2) and the turbine lower positioning block (8) are provided with flow passages; the drilling fluid can push the turbine blades (4) through the turbine upper positioning block (2), thereby further The turbine shaft (6) is driven to rotate; after that, the drilling fluid can pass through the lower positioning block (8) of the turbine, a part of which is ejected from the nozzle (11) of the extended large drill bit, and the other part enters the small central drill bit (12) through the guide joint (9) .

For the two-speed PDC bit driven by the turbine in the above scheme, the assembly sequence is as follows: first, the turbine blade 4 is assembled on the turbine shaft 6, and the guide joint 9 is threadedly connected at the lower end of the turbine shaft 6 to form an integral part; The positioning block 8 is installed into the epitaxial large drill bit 5, the small steel ball 7 is installed in the groove of the lower positioning block 8 of the turbine, the sealing ring 10 is installed in the groove of the epitaxial large drill bit 5, and the above-mentioned integral parts are installed into the epitaxial large drill bit 5 ; Load the large steel ball 3 on the upper end of the turbine shaft 6, and then load the positioning block 2 on the turbine, and connect the upper joint 1 through the screw thread; Install the extension large drill bit nozzle 11 on the epitaxial large drill bit 5, and the assembly is completed.

Claims (6)

1. A two-speed PDC drill driven by a turbine, consisting of an upper joint (1), a positioning block on the turbine shaft (2), a large steel ball (3), a turbine blade (4), an epitaxial large drill bit (5), and a turbine shaft (6) ), a small steel ball (7), a positioning block (8) under the turbine shaft, a guide joint (9), a Y-shaped sealing ring (10), a large extension drill nozzle (11), and a small center drill (12). Yes: the assembly sequence is to first assemble the turbine blade (4) on the turbine shaft (6), and connect the upper guide joint (9) to the lower end of the turbine shaft (6) by threaded connection to form an integral part; give the extension large drill bit (5) Install the epitaxial large drill nozzle (11), install the Y-shaped sealing ring (10) on the groove of the epitaxial large drill (5), and install the turbine lower positioning block (8) into the epitaxial large drill (5). A small steel ball (7) is installed in the groove of the lower positioning block (8), and the above-mentioned integral part is installed into an epitaxial large drill bit (5); the other end of the guide joint (9) is connected with a small central drill bit (12) by threads; A large steel ball (3) is installed on the upper end of the turbine shaft (6), and then the upper positioning block (2) of the turbine is installed, and the upper joint (1) is connected by a thread, and the assembly is completed. 2. The two-speed PDC drill bit based on turbine drive according to claim 1, characterized in that: three oblique holes uniformly distributed in the circumferential direction are opened on the guide joint (9), and the drilling fluid extends from the epitaxial large drill bit (5) The annular space between the diversion joint (9) and the diversion joint (9) enters the diversion joint (9) through the inclined hole, and then enters the small central drill bit (12), and is ejected from the nozzle of the small central drill bit (12) during drilling. It is beneficial to reduce the pressure drop of drilling fluid. 3. The two-speed PDC drill bit based on turbine drive according to claim 1, characterized in that: there are grooves on the turbine lower positioning block (8) and the turbine shaft (6), and small steel balls are loaded between the two grooves (7); During drilling, the turbine shaft (6) drives the small central drill bit (12) to rotate to break the rock, thereby reducing the frictional resistance between the lower turbine positioning block (8) and the turbine shaft (6). 4. The two-speed PDC drill bit based on turbine drive according to claim 1, characterized in that: there are pits on the upper end of the turbine shaft (6) and the positioning block (2) on the turbine, and are installed between the two pits The large steel ball (3); when drilling, the turbine shaft (6) drives the small central drill bit (12) to rotate to break the rock, thereby reducing the frictional resistance between the positioning block (2) on the turbine and the turbine shaft (6). 5. The two-speed PDC drill bit based on turbine drive according to claim 1, characterized in that: two Y-shaped sealing rings (10) are designed between the epitaxial large drill bit (5) and the guide joint (9), and the two The opening directions of the Y-shaped sealing rings (10) are opposite, with the upper one facing upwards and the lower one facing downwards; it can prevent drilling fluid from flowing out or flowing in between the extended large drill bit (5) and the guide joint (9). 6. The two-speed PDC drill bit based on turbine drive according to claim 1, characterized in that: the upper positioning block (2) of the turbine and the lower positioning block (8) of the turbine are provided with an overflow channel; the drilling fluid can be positioned by the upper turbine The block (2) pushes the turbine blades (4), which in turn drives the turbine shaft (6) to rotate; after that, the drilling fluid can pass through the lower positioning block (8) of the turbine, and part of it is ejected from the epitaxial large drill nozzle (11), and the other part is injected through the guide. The flow joint (9) enters the small central drill bit (12), which is ejected from the nozzle.