1. The utility model provides a drilling rod connecting device is used in float shoe well cementation which characterized in that includes: an upper connector, a lower connector and a helical structure; the upper connector is used for being connected with a drill rod, and the lower connector is used for being connected with the insertion head; the lower connector is connected with the upper connector, and the lower connector can move up and down relative to the upper connector;

the screw structure is disposed between the upper connector and the lower connector, the screw structure being configured to rotate the lower connector relative to the upper connector when the lower connector moves up and down relative to the upper connector.

2. The float shoe well cementation drill pipe connection device of claim 1, wherein the upper connector is provided with a sliding bore through which the lower connector is slidably disposed.

3. The connection device for the floating shoe cementing drill pipe according to claim 2, wherein the spiral structure comprises a spiral groove and a sliding block which is slidably embedded in the spiral groove, the spiral groove is arranged on the outer side wall of the lower connector, and the sliding block is arranged on the inner wall of the sliding hole.

4. The connection device for the drill rod for the float shoe well cementation according to claim 3, wherein the sliding block and the upper connector are of a split structure, a block through hole is formed in the side wall of the sliding hole, and the sliding block is arranged in the block through hole in a penetrating mode.

5. The connection device for the drill rod for the float shoe well cementation according to claim 4, characterized in that a nut press ring is connected outside the upper connector, the nut press ring surrounds the slippage blocks, and the outer end of each slippage block abuts against the inner wall of the nut press ring.

6. The connection device for the float shoe cementing drill pipe according to claim 3, characterized in that the outer side wall of the lower connector is provided with a plurality of spiral grooves distributed at intervals on the circumference.

7. The float shoe cementing drill pipe connection device according to claim 2, wherein the slide bore comprises an upper bore portion and a lower bore portion, the upper bore portion having an inner diameter smaller than an inner diameter of the lower bore portion; the lower connector comprises an upper column part matched with the upper hole part and a lower column part matched with the lower hole part, and sealing rubber rings are respectively arranged on the side walls of the upper column part and the lower column part.

8. The float shoe well cementing drill pipe connection device of claim 1, comprising a resilient mechanism disposed between the upper connector and the lower connector, the resilient mechanism configured to provide resistance to the lower connector approaching the upper connector.

9. The float shoe well cementing drill pipe connection device of claim 8, wherein the resilient mechanism comprises a spring.

10. A float shoe cementing pipe string, characterized by comprising an insertion head, a drill pipe, and a float shoe cementing drill pipe connecting device according to any one of claims 1 to 9;

the insertion head is connected to the lower connector, and the drill rod is connected to the upper connector.

Background

The well cementation operation in the operation process of the drilling method is the most important and lays the foundation for the subsequent drilling operation. After the surface layer water-stop pipe is lowered to a specified depth, well cementation operation must be carried out as soon as possible, and if a fault occurs in the process of the well cementation operation, a series of operation accidents such as well wall collapse can be caused.

The large-diameter surface layer water-resisting guide pipe is required to use a floating shoe when the operation is carried out by adopting a drilling method. Adopt the float shoe to carry out the well cementation operation, during the operation, need with the inside insert head of float shoe case matching inside, the filling of grout can be carried out to the cooperation part of both through the rubber ring after sealed. The insert head is installed on the drilling rod the lower extreme, transfers with the drilling rod together, when transferring to appointed marine riser bottom, and the insert head inserts inside the float shoe case.

In the above-mentioned operation, sometimes the drilling rod centralizer appears damaging, leads to the drilling rod not to be in the central state in the marine riser inside, and the plug-in head is difficult to insert smoothly inside the float shoe case. Sometimes, the arrangement of the floating shoe is not good, the valve core of the floating shoe is in a skew state in the floating shoe, and the valve core of the floating shoe and the drill rod are not concentric, so that the insertion head cannot be smoothly inserted into the valve core of the floating shoe. If the two conditions occur, the insertion head can be directly propped against the cement on the upper part of the float shoe or the upper end part of the valve core, and the insertion head can not be smoothly inserted into the float shoe for well cementation.

Disclosure of Invention

The invention aims to provide a drill rod connecting device for float shoe well cementation and a float shoe well cementation tubular column, which are used for relieving the technical problem that an insertion head cannot be smoothly inserted into a float shoe valve core in well cementation operation.

The above object of the present invention can be achieved by the following technical solutions:

the invention provides a drill rod connecting device for float shoe cementing, which comprises: an upper connector, a lower connector and a helical structure; the upper connector is used for being connected with a drill rod, and the lower connector is used for being connected with the insertion head; the lower connector is connected with the upper connector, and the lower connector can move up and down relative to the upper connector; the screw structure is disposed between the upper connector and the lower connector, the screw structure being configured to rotate the lower connector relative to the upper connector when the lower connector moves up and down relative to the upper connector.

In a preferred embodiment, the upper connector is provided with a sliding hole, and the lower connector is slidably disposed through the sliding hole.

In a preferred embodiment, the helical structure includes a helical groove and a sliding block slidably embedded in the helical groove, the helical groove is disposed on an outer side wall of the lower connector, and the sliding block is disposed on an inner wall of the sliding hole.

In a preferred embodiment, the sliding block and the upper connector are of a split structure, a block through hole is formed in a side wall of the sliding hole, and the sliding block is arranged in the block through hole in a penetrating mode.

In a preferred embodiment, a nut press ring is connected to the outside of the upper connector, the nut press ring surrounds the sliding blocks, and the outer end of each sliding block abuts against the inner wall of the nut press ring.

In a preferred embodiment, the outer side wall of the lower connector is provided with a plurality of circumferentially spaced helical grooves.

In a preferred embodiment, the sliding hole includes an upper hole portion and a lower hole portion, the upper hole portion having an inner diameter smaller than an inner diameter of the lower hole portion; the lower connector comprises an upper column part matched with the upper hole part and a lower column part matched with the lower hole part, and sealing rubber rings are respectively arranged on the side walls of the upper column part and the lower column part.

In a preferred embodiment, the float shoe well cementation drill pipe connection includes a resilient mechanism disposed between the upper connector and the lower connector, the resilient mechanism configured to provide resistance to the lower connector approaching the upper connector.

In a preferred embodiment, the resilient means comprises a spring.

The invention provides a float shoe well cementation tubular column which comprises an insertion head, a drill rod and the float shoe well cementation drill rod connecting device, wherein the insertion head is connected with the drill rod; the insertion head is connected to the lower connector, and the drill rod is connected to the upper connector.

The invention has the characteristics and advantages that:

when the floating shoe valve core is not centered or the drill rod centralizer is damaged to cause the insertion head to be not centered, the drill rod connecting device for floating shoe well cementation can promote the insertion head to adjust the position to be aligned with the floating shoe valve core, so that the insertion head can be smoothly inserted into the floating shoe, and the well cementation operation is guaranteed. The beneficial effect that this drilling rod connecting device produced includes: (1) the difficulty of aligning the insertion head with the float shoe valve core is reduced, the drill rod connecting device is beneficial to the insertion of the insertion head into the float shoe valve core, the condition that the insertion head cannot be inserted into the float shoe valve core is reduced, and well cementation operation is guaranteed; (2) the efficiency of well cementation operation is effectively improved, and the difficulty in well cementation is reduced; (3) the efficiency of the opposite insertion of the insertion head and the floating shoe is improved; (4) reduce the damage to the guide surface of the insert head or the float shoe.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

1-3 are working process diagrams of the floating shoe well cementation drill rod connecting device provided by the invention;

FIG. 4 is a schematic structural diagram of a floating shoe well cementing drill pipe connecting device provided by the invention;

FIG. 5 is a schematic view of the upper connector of the floating shoe well cementing drill pipe connecting device shown in FIG. 4;

FIG. 6 is a schematic diagram of a nut press ring in the float shoe well cementing drill pipe connecting device shown in FIG. 4;

FIGS. 7-8 are schematic views of the lower connector of the float shoe well cementing drill pipe connecting device shown in FIG. 4;

9-10 are schematic structural views of the sliding block in the floating shoe well-cementing drill rod connecting device shown in FIG. 4;

FIG. 11 is a schematic structural view of an anti-rotation pin in the floating shoe well cementing drill pipe connecting device shown in FIG. 4.

The reference numbers illustrate:

10. floating shoes; 9. an insertion head; 91. a drill stem;

1. an upper connector; 11. a drill rod female buckle; 14. a threaded hole; 15. an external threaded portion; 16. a block through hole;

120. a slide hole; 12. an upper hole portion; 13. a lower hole portion;

2. an upper sealing rubber ring; 8. a lower sealing rubber ring;

30. an elastic mechanism; 3. a spring;

5. pressing a ring by a nut; 51. perforating the pin; 52. an internal thread portion; 4. anti-rotation pins;

60. a helical structure; 6. a sliding block; 75. a helical groove;

7. a lower connector; 72. an upper column portion; 74. a lower column portion;

71. an upper seal ring groove; 73. a lower seal ring groove; 76. and (4) drilling rod male buckles.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

The invention provides a drill rod connecting device for floating shoe well cementation, which comprises the following components in percentage by weight as shown in figure 4: upper connector 1, lower connector 7 and helix 60; the upper connector 1 is used for connecting with a drill rod 91, and the lower connector 7 is used for connecting with an insertion head 9; the lower connector 7 is connected with the upper connector 1, and the lower connector 7 can move up and down relative to the upper connector 1; the screw structure 60 is provided between the upper connector 1 and the lower connector 7, and the screw structure 60 is configured to rotate the lower connector 7 relative to the upper connector 1 when the lower connector 7 moves up and down relative to the upper connector 1.

In the drilling operation, after the riser string is connected and lowered in place, the drill rod connecting device is connected with the drill rod 91, and the insertion head 9 is installed at the lower end of the drill rod connecting device. As shown in fig. 1 and 2, after the insertion head 9 is lowered to contact the cement guide surface, the lower ends of the lower connector 7 and the insertion head 9 are subjected to resistance, and the lower connector 7 and the insertion head 9 move upward relative to the upper connector 1; since the drill rod 91 and the upper connector 1 do not rotate, the lower connector 7 and the insertion head 9 rotate. The upper surface of the interior of the float 10 is usually provided with a guide surface of cement in the form of a cone, on which the lower connector 7 and the insertion head 9 are moved by rotation to a lower central position. With rotation and sliding, the insertion head 9 reaches the central position of the float shoe 10 on the cement guide surface, and insertion into the valve core of the float shoe 10 is realized.

When the valve core of the float shoe 10 is not centered or the insert head 9 is not centered due to the damage of the centralizer of the drill rod 91, the drill rod connecting device for float shoe well cementation can promote the insert head 9 to adjust the position to be aligned with the valve core of the float shoe 10, so that the insert head 9 can be smoothly inserted into the float shoe 10, and the well cementation operation is guaranteed. The beneficial effect that this drilling rod connecting device produced includes: (1) the difficulty of aligning the insert head 9 with the valve core of the float shoe 10 is reduced, the drill rod connecting device is beneficial to the insert head 9 to insert the valve core of the float shoe 10, the condition that the insert head 9 cannot be inserted into the valve core of the float shoe 10 is reduced, and the well cementation operation is guaranteed; (2) the efficiency of well cementation operation is effectively improved, and the difficulty in well cementation is reduced; (3) the efficiency of inserting the inserting head 9 and the floating shoe 10 is improved; (4) the damage to the guide surface of the insert head 9 or the float 10 is reduced.

The floating shoe well cementation drill rod connecting device is not limited to be applied to the floating shoe 10 with the conical guide surface, and under the condition that the guide surface of the floating shoe 10 is a plane, the lower connector 7 and the insertion head 9 rotate, so that the resistance of the insertion head 9 in the movement of the guide surface is reduced, and the insertion head 9 can be conveniently adjusted to move to be aligned with the valve core of the floating shoe 10.

For the rigid connection between the drill rod 91 and the insertion head 9, the drill floor needs to rotate to drive the drill rod 91 and the insertion head 9 to rotate, and the insertion head 9 is already in contact with the bottom, so that the difficulty in adjusting the position of the insertion head 9 is high. Compared with the case that the drill rod 91 is rigidly connected with the insertion head 9, the difficulty of adjusting the position of the insertion head 9 to insert the valve core of the floating shoe 10 is lower under the condition of using the drill rod connecting device.

In one embodiment, the upper end of the upper connector 1 is a drill rod box 11 to facilitate connection with a drill rod 91; the upper connector 1 has a grout passage inside. The lower end of the lower connector 7 is provided with a drill rod male buckle 76 so as to be connected with the insertion head 9, and the inside of the lower connector 7 is provided with a cement slurry drift diameter. When the drill rod connecting device is used, the drill rod 91 is lowered to the depth of the insertion head 9 close to the position of the floating shoe 10, and then the drill rod 91 is slowly lowered until the dead weight of the drill rod 91 completely acts on the floating shoe 10.

The connection manner between the upper connector 1 and the lower connector 7 is not limited to one, for example: the upper connector 1 is sleeved outside the lower connector 7, or the lower connector 7 is sleeved outside the upper connector 1. In one embodiment, the upper connector 1 is provided with a sliding hole 120, the lower connector 7 is slidably inserted into the sliding hole 120, and the sliding hole 120 guides the up-and-down movement of the lower connector 7.

Further, as shown in fig. 5, 7 and 8, the slide hole 120 includes an upper hole portion 12 and a lower hole portion 13, an inner diameter of the upper hole portion 12 being smaller than an inner diameter of the lower hole portion 13; lower connector 7 includes an upper post portion 72 fitted to upper hole portion 12 and a lower post portion 74 fitted to lower hole portion 13, and the side walls of upper post portion 72 and lower post portion 74 are provided with a sealing rubber ring, respectively. As shown in fig. 4, the sealing rubber ring arranged on the upper column part 72 is an upper sealing rubber ring 2, and the upper sealing rubber ring 2 is used for sealing the upper ends of the lower connector 7 and the upper connector 1 to prevent cement slurry from leaking out in the well cementation process; the sealing rubber ring provided at the lower column part 74 is a lower sealing rubber ring 8, and the lower sealing rubber ring 8 is used for sealing the lower end of the lower connector 7 and the lower end of the upper connector 1, and preventing seawater from entering the sliding hole 120 to corrode internal components such as the spring 3. Through upper seal rubber ring 2 and lower seal rubber ring 8, strengthened sealed function, effectively prevent that grout from overflowing through drilling rod 91, also can effectively prevent that sea water from getting into inside drilling rod 91.

In one embodiment, the helical structure 60 includes a helical groove 75 and a sliding block 6 slidably embedded in the helical groove 75, the helical groove 75 and the sliding block 6 are respectively disposed on the upper connector 1 and the lower connector 7, and when the sliding block 6 is subjected to a vertical force, the sliding block 6 performs a helical motion along the helical groove 75 under the guiding action of the helical groove 75, so as to drive the lower connector 7 and the upper connector 1 to rotate relatively. Preferably, the spiral groove 75 is disposed on the outer side wall of the lower connector 7, the sliding block 6 is disposed on the inner wall of the sliding hole 120, and the sliding block 6 is fixed, so that when the sliding block 6 moves relatively in the spiral groove 75 of the lower connector 7, the lower connector 7 is driven by the sliding block 6 to rotate. As shown in fig. 9 and 10, the sliding block 6 is provided with a protrusion on one side, which matches the spiral groove 75 and can slide along the spiral groove 75.

Further, the sliding block 6 and the upper connector 1 are of a split structure, a block through hole 16 is formed in the side wall of the sliding hole 120, and the sliding block 6 is arranged in the block through hole 16 in a penetrating mode so that the lower connector 7 can be conveniently installed in the sliding hole 120. The sliding block 6 is fixedly connected with the upper connector 1. As shown in fig. 4-6, the nut press ring 5 is connected outside the upper connector 1, the nut press ring 5 surrounds the sliding blocks 6, the outer end of each sliding block 6 abuts against the inner wall of the nut press ring 5, the nut press ring 5 can prevent the sliding block 6 from coming out of the block through hole 16, and the connection stability between the upper connector 1 and the lower connector 7 is improved. After the nut pressing ring 5 is disassembled, the sliding block 6 can be taken out from the block through hole 16, so that the assembly and the disassembly are convenient, and the maintenance is convenient.

The nut press ring 5 is screwed to the upper connector 1, and as shown in fig. 4, 6 and 11, the nut press ring 5 has an internal threaded portion 52 for connection to the upper connector 1 inside, and the external threaded portion 15 fitted to the internal threaded portion 52 is provided on the outer wall of the upper connector 1; the upper portion of the nut press ring 5 is provided with a pin perforation 51, the anti-rotation pin 4 penetrating the pin perforation 51 is fixed on the upper connector 1, the anti-rotation pin 4 prevents the nut press ring 5 from rotating, and the anti-rotation pin 4 can adopt an inner hexagon bolt with an external thread.

As shown in fig. 7, the outer side wall of the lower connector 7 is provided with a plurality of spiral grooves 75 circumferentially spaced apart, and a plurality of sliding blocks 6 are respectively installed in the spiral grooves 75 to drive the lower connector 7 to rotate smoothly. Preferably, the lead angle of the helical groove is 60 °.

In an embodiment, the drill rod coupling device comprises a resilient means 30 arranged between the upper connector 1 and the lower connector 7, the resilient means 30 being configured to create a resistance to the lower connector 7 approaching the upper connector 1. The elastic mechanism 30 reserves a space for the relative up-and-down movement of the upper connector 1 and the lower connector 7, after the insertion head 9 is bottomed, the elastic mechanism 30 is compressed, the upper connector 1 can move downwards, and the upper connector 1 and the lower connector 7 generate the relative up-and-down movement, so that the sliding block 6 moves in the spiral groove 75 to drive the lower connector 7 to rotate. After the insertion head 9 is inserted into the float shoe 10, the pressing down is continued until the elastic means 30 is completely compressed and stops when the lower connector 7 and the upper connector 1 cannot be displaced any more. At this time, the grouting operation can be started after the up-and-down movement of the drill pipe 91 is limited.

By the elastic mechanism 30, the insertion head 9 can not suddenly generate large impact when contacting with the guide surface of the floating shoe 10, which is beneficial to protecting the end part and the guide surface of the insertion head 9; elastic mechanism 30 has the buffering effect, can avoid because rigid connection, insert head 9 to the inside cement face of float shoe 10 produce great impact to reduce the cement face because of assaulting the condition that the pothole appears, reduce and insert head 9 and receive the condition that the impact and appear damaging, make insert head 9 repeatedly usable. Through the elastic mechanism 30, the drill rod connecting device has an automatic reset function, can automatically reset after well cementation is finished, does not need manual reset operation in next use, and can improve the operation efficiency.

Further, the elastic mechanism 30 includes a spring 3, the spring 3 is located between the upper connector 1 and the lower connector 7, and plays a role of buffering and also plays a role of restoring, as shown in fig. 4, the spring 3 is sleeved outside the upper column part 72.

The installation steps of the drill rod connecting device comprise: (1) installing the upper sealing rubber ring 2 into an upper sealing ring groove 71 of the upper connector 1, and installing the lower sealing rubber ring 8 into a lower sealing ring groove 73 of the upper connector 1; (2) installing a spring 3 inside the upper connector 1; (3) the lower connector 7 is assembled with the upper connector 1; (4) installing the sliding block 6 in the block through hole 16 of the upper connector 1, and installing the bulge of the sliding block 6 in the spiral groove 75 of the lower connector 7; (5) the nut press ring 5 is installed outside the upper connector 1 through thread matching until the nut press ring 5 can completely cover the sliding block 6; (6) and installing the anti-rotation pin 4, screwing the anti-rotation pin 4 to the threaded hole 14 of the upper connector 1 through the pin perforation 51 of the nut press ring 5, and fastening.

The field application use method of the drill rod connecting device comprises the following steps: (1) the drill rod connecting device is lowered to the position of the floating shoe 10 and contacts the cement guide surface, the lower ends of the lower connector 7 and the inserting head 9 are subjected to resistance, the spring 3 is compressed, and when the sliding block 6 and the lower connector 7 move relatively through the spiral groove 75, the lower connector 7 rotates; (2) the rotation of the lower connector 7 and the insertion head 9 can make the lower connector move to a lower central position on the cement guide surface, and when the lower connector and the insertion head 9 rotate to the central position, the insertion head 9 is inserted into the floating shoe 10; (3) after the insertion head 9 is inserted into the float shoe 10, the downward pressure is continued until the spring 3 is completely compressed, the lower connector 7 and the upper connector 1 stop generating displacement, and at the moment, the grouting operation can be started after the up-and-down movement of the drill rod 91 is limited.

Example two

The invention provides a floating shoe well cementation tubular column, which comprises an insertion head 9, a drill rod 91 and the floating shoe well cementation drill rod connecting device, wherein the insertion head 9 is connected to a lower connector 7, and the drill rod 91 is connected to an upper connector 1. When the float shoe well cementation pipe column is used for well cementation, when the valve core of the float shoe 10 is not centered or the insertion head 9 is not centered due to the damage of the centralizer of the drill stem 91, the insertion head 9 can rotate and slide to reach the central position of the float shoe 10 on the cement guide surface, so that the float shoe well cementation pipe column can be inserted into the valve core of the float shoe 10, and the well cementation operation is guaranteed. The beneficial effects that this float shoe well cementation tubular column produced include: (1) the difficulty of aligning the insert head 9 with the valve core of the float shoe 10 is reduced, the insert head 9 is facilitated to be inserted into the valve core of the float shoe 10, the condition that the insert head 9 cannot be inserted into the valve core of the float shoe 10 is reduced, and the well cementation operation is guaranteed; (2) the efficiency of well cementation operation is effectively improved, and the difficulty in well cementation is reduced; (3) the efficiency of inserting the inserting head 9 and the floating shoe 10 is improved; (4) the damage to the guide surface of the insert head 9 or the float 10 is reduced.

The above description is only a few embodiments of the present invention, and those skilled in the art can make various changes or modifications to the embodiments of the present invention according to the disclosure of the application document without departing from the spirit and scope of the present invention.