Novel self-grouting float collar convenient to use

Abstract

The invention relates to a novel self-grouting float collar convenient to use. The novel self-grouting float collar comprises an outer barrel shell. A sealing seat with a through hole is arranged in the outer barrel shell, an overflowing circular plate is mounted on one side of the sealing seat, a sealing rod is movably inserted in the center of the overflowing circular plate, the sealing rod penetrates through the overflowing circular plate and is inserted into a barrier plate, and a spring A is sleeved on a rod body of the sealing rod; the blocking plate is connected with a limiting mechanism, the limiting mechanism comprises two limiting columns, the two limiting columns are connected through an elastic rope, the limiting columns are connected with the inner wall of the outer barrel shell through a spring B, the sealing rod directly faces the elastic rope, and a blade is arranged at the end of the sealing rod. The sealing rod is fixed through the limiting mechanism, the sealing rod and the sealing seat are not sealed, and the cement paste is reversely conducted; cement paste is poured downwards, the spring A is compressed, the blade of the sealing rod cuts off the elastic rope, and the limiting column retracts through the spring B; limiting is not needed any more after grouting is stopped, and a one-way valve closed state is formed between the sealing rod and the sealing seat. The float collar has the beneficial effects that use is convenient, grouting time is saved, and the sealing performance of the float collar is improved.

Description

Technical Field

[0001] The invention relates to the technical field of downhole tools for oil and gas field development, in particular to a novel self-grouting floating collar that is easy to use. Background Art

[0002] At present, during the casing operation in oil and gas fields, a floating collar is installed at the bottom of the casing. The conventional floating collar commonly used on the market is essentially a one-way valve, which can only allow the liquid to flow in the forward direction, that is, it can only flow from the inside of the pipe to the outside of the pipe. Therefore, during the casing operation, each casing section needs to be paused to inject drilling fluid into the casing to avoid the situation where the casing buoyancy is greater than the casing gravity and the casing cannot be lowered. This process of injecting drilling fluid takes a certain amount of time, which reduces the efficiency of lowering the casing into the well.

[0003] Therefore, some floating hoops that can achieve self-grouting have also appeared on the market, which can basically be divided into float type self-grouting floating hoops and sliding sleeve plus flow hole type self-grouting floating hoops; for example, a ball-throwing float type self-grouting floating hoops disclosed in application number CN202110300352.9 mainly utilizes the characteristics of low-density floats that can float in drilling fluid, thereby realizing the switching function, but when the floating hoop is located in a highly deviated well or a horizontal well, the float may not be able to move according to the preset requirements, and the self-grouting function of the floating hoop cannot be well realized; and a self-grouting floating hoop disclosed in application number CN210798891U adopts a sliding sleeve plus flow hole structure, and its sealing valve core is sealed only by the elastic force of the spring sleeve on the sealing valve, and long-term use will cause the spring to fail, thereby causing the tightness between the sealing valve core and the grouting channel to be reduced, thereby the sealing effect is deteriorated, and when the check valve function is restored, the limit component fails and may be lost or damaged, which may bring risks to the next construction.

[0004] Therefore, based on the customer's feedback on the shortcomings of the existing self-grouting floating collar, the inventor has made further improvements according to the proposed defects and deficiencies to overcome the above problems. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a new self-grouting floating hoop that is easy to use and can effectively accommodate a limiting component to prevent the limiting component from affecting the flow of cement slurry or being damaged; improve the sealing performance of the floating hoop and ensure the stability of the floating hoop when sealing.

[0006] The object of the present invention is achieved through the following technical solutions: a new self-grouting floating collar which is easy to use, comprising an outer cylinder shell, a sealing rod, a baffle plate and a flow-through circular plate;

[0007] A sealing seat with a through hole is provided in the middle and upper part of the outer cylinder shell, a flow circular plate is installed on one side of the sealing seat, a plurality of flow holes are provided on the flow circular plate, and a sealing rod can be movably inserted in the center of the flow circular plate, one end of the sealing rod is located at the through hole of the sealing seat, and the sealing rod passes through the flow circular plate and a blocking plate, and a spring A is sleeved on the sealing rod;

[0008] The blocking plate is connected to the limiting mechanism, which includes an elastic rope and a limiting column. The two limiting columns are arranged opposite to each other and are connected by the elastic rope. The two limiting columns are connected to the left and right inner walls of the corresponding outer cylinder shell by a spring B. The other end of the sealing rod faces the elastic rope and a blade is arranged at the end to cut the elastic rope.

[0009] When cement slurry flows from the flow circular plate to the sealing seat, the blocking plate and the sealing rod are fixed by the limiting mechanism, and the sealing rod and the sealing seat are not sealed, thereby realizing reverse conduction of cement slurry; when cement slurry flows from the sealing seat to the flow circular plate, spring A is compressed, the sealing rod presses down the blade at its end to cut the elastic rope, and the limiting column retracts through spring B; after the grouting is stopped, the limiting mechanism no longer limits, and a closed state is formed between the sealing rod and the sealing seat.

[0010] As a preferred technical solution of the present application, a plurality of short columns are provided on the end surface of the baffle plate facing the flow circular plate, and a plurality of short column grooves are provided on the flow circular plate corresponding to the positions of the plurality of short columns, and a spring C is arranged in the short column groove, and the spring C is connected to the short column; the baffle plate is pulled by a limiting mechanism so that the baffle plate and the flow circular plate are separated by a certain distance, which is conducive to the reverse conduction of cement slurry; after the sealing rod is pressed down and the elastic rope is cut by a blade, the baffle plate is fitted with the flow circular plate through the spring C to form a sealing state.

[0011] As a preferred technical solution of the present application, the multiple short column grooves are opened on the circumferential edge of the flow circular plate, and they do not interfere with the multiple flow holes on the flow circular plate.

[0012] As a preferred technical solution of the present application, a mounting groove is provided on the end surface of the baffle plate facing away from the flow circular plate, the sealing rod is inserted into the mounting groove and a sliding path is provided between the sealing rod and the mounting groove, the sealing rod can move along the sliding path and extend the end blade to cut the elastic rope.

[0013] As a preferred technical solution of the present application, the spring A is sleeved outside the sealing rod body, and one end of the spring A abuts against the lower side of the umbrella-shaped end of the sealing rod, and the other end abuts against the end surface of the flow circular plate.

[0014] As a preferred technical solution of the present application, the sliding channel is a plurality of vertical grooves opened inside the installation groove, a short protrusion is opened at the lower part of the sealing rod to adapt to the vertical groove, and the short protrusion is blocked at the lower end of the installation groove.

[0015] As a preferred technical solution of the present application, two mounting plates are relatively arranged at the lower end of the mounting groove, and the mounting plates are opened with holes, in which limit columns are inserted, the two limit columns are relatively arranged and an elastic rope is connected between the two, and a groove is opened on the inner wall of the outer cylinder shell relative to the position of the limit column. After the elastic rope is cut off, the spring B retracts the limit column into the groove to avoid blocking the cement slurry.

[0016] As a preferred technical solution of the present application, the limiting mechanism includes a spring seat, a lock tongue, and a lock tongue spring; the spring seat is inserted and fixed at the center of the flow circular plate, a long rod can be movably inserted in the spring seat, an elastic member is sleeved on the long rod, the end of the long rod is facing the through hole of the sealing seat and its tail passes through the flow circular plate through the spring seat, the long rod is limited by the lock tongue and the spring seat, the lock tongue is arranged at the tail end of the spring seat and is vertically inserted into the spring seat and the tail of the long rod, a lock tongue spring is sleeved on the lock tongue, one end of the lock tongue spring is against the outside of the spring seat, and the other end is against the end of the lock tongue;

[0017] The lock tongue is inserted into the tail of the long rod into the spring seat for locking and fixing. At this time, the lock tongue spring is compressed, the long rod and the sealing seat are not closed, and the cement slurry can flow from the flow circular plate to the sealing seat to realize reverse conduction; when the cement slurry is forwardly conducted, the long rod is pressed down, the lock tongue retracts and exits the long rod, and the lock tongue spring is not compressed; after the grouting is stopped, the lock tongue is no longer limited, and the long rod and the sealing seat are closed.

[0018] The present invention has the following advantages:

[0019] (1) Effectively store the limiting components to prevent them from affecting the flow of cement slurry or being damaged;

[0020] The existing self-grouting floating hoop achieves the self-grouting effect by limiting the sealing valve through the cooperation of limiting components such as floats and springs. However, when the cement slurry is poured, the existence of the limiting components will affect the flow of the cement slurry, or be damaged or lost due to the scouring of the cement slurry. The new self-grouting floating hoop designed in this scheme adopts a limiting mechanism composed of a limiting column, an elastic rope and a spring B that cooperate with each other. A blade is provided at the tail of the sealing rod, which can cut the elastic rope when under pressure, so that the limiting column retracts into the groove on the inner wall of the outer cylinder shell, which will not affect the subsequent flow of cement slurry and will not cause the limiting components to be lost or damaged due to impact. Through the structural design of this scheme, the reverse conduction and forward penetration and closure of cement slurry can be effectively realized, which improves the convenience and reliability of the use of the floating hoop. When the sealing rod is pressed down, it can accurately cut the elastic rope, quickly and effectively restore the one-way valve function, and at the same time improve the response speed and reliability of the limiting mechanism of the floating hoop.

[0021] (2) Improve the sealing performance of the floating collar and ensure the stability of the floating collar during sealing;

[0022] The sealing structure of the sealing valve in most existing floating hoops is too simple, and the sealing valve core is sealed only by the elastic force of the spring. After long-term use, the spring of the sealing valve fails, resulting in a decrease in the tightness between the sealing valve core and the grouting channel, which makes it impossible to seal, and finally leads to leakage and backflow of cement slurry; the new self-grouting floating hoop designed in this scheme is designed with a baffle plate, which is arranged on one side of the flow circular plate, and the baffle plate and the flow circular plate are connected to the spring C through a short column. When the cement slurry flows from the sealing seat to the flow circular plate, the blade at the tail end of the sealing rod cuts the elastic rope to release the limit, and the spring C retracts and resets, so that the baffle plate fits with the flow circular plate, which can play a sealing role. The baffle plate is sealed with the flow circular plate, and the sealing rod and the sealing seat can be sealed at the same time. The device achieves a double sealing effect, which can effectively improve the sealing performance of the floating hoop and ensure the stability of the floating hoop when sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the present invention in a half-surface cross-section at a first viewing angle;

[0024] Figure 2 It is a structural schematic diagram of the present invention in a half-surface cross-section at a second viewing angle;

[0025] Figure 3 It is a schematic diagram of the structure after the sealing rod, the flow circular plate and the blocking plate of the present invention are installed;

[0026] Figure 4 It is a schematic structural diagram of a half-section view of the sealing rod, the flow circular plate and the baffle plate after installation of the present invention;

[0027] Figure 5 It is a structural schematic diagram of the sealing rod and the limiting mechanism of the present invention;

[0028] Figure 6 It is a structural schematic diagram of the blocking plate of the present invention;

[0029] Figure 7 It is a structural schematic diagram of a half-section view of a blocking plate of the present invention;

[0030] Figure 8 It is a schematic structural diagram of a half-surface cross-section of a first viewing angle of embodiment 2 of the present invention;

[0031] Fig. 9 It is a schematic structural diagram of a half-surface cross-section of a second viewing angle of embodiment 2 of the present invention;

[0032] In the figure: 1-outer cylinder shell, 2-sealing rod, 3-blocking plate, 4-flow circular plate, 5-sealing seat, 6-spring A, 7-elastic rope, 8-limiting column, 9-spring B, 10-spring C, 11-blade, 12-short column, 13-sliding path, 14-short protrusion, 15-mounting plate, 16-groove, 17-spring seat, 18-long rod, 19-lock tongue, 20-lock tongue spring. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following description.

[0034] It should be noted that the directions or positional relationships indicated by "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use, or are the directions or positional relationships commonly understood by those skilled in the art. Such terms are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0036] Therefore, based on the above issues, see Figure 1 The present invention proposes a novel self-grouting floating hoop which is easy to use to solve the problem.

[0037] (Example 1)

[0038] See also Figures 1 to 9 The embodiment of the present invention provides a new type of self-grouting floating collar which is easy to use, including an outer cylinder shell 1, a sealing rod 2, a blocking plate 3, a limiting mechanism and a flow circular plate 4;

[0039] Among them, see Figure 1 The outer cylinder shell 1 is cylindrical and a sealing seat 5 is arranged at the middle upper position inside the outer cylinder shell 1. A through hole for cement slurry to pass through is provided in the center of the sealing seat 5. A sealing rod 2, a flow circular plate 4 and a blocking plate 3 are installed on one side of the sealing seat 5, i.e., the middle and lower part of the outer cylinder shell 1;

[0040] Among them, see Figure 1 and Figure 2 The flow circular plate 4 is fixedly installed inside the outer cylinder shell 1 and a plurality of flow holes are evenly distributed on the flow circular plate 4. A sealing rod 2 is movably inserted at the center of the flow circular plate 4. One end of the sealing rod 2 is an umbrella-shaped end, which is arranged opposite to the through hole of the sealing seat 5, and the other end thereof penetrates the flow circular plate 4 and is connected with the blocking plate 3; the blocking plate 3 has a hole in the center and is protruded with a mounting groove facing away from the sealing seat 5. The sealing rod 2 is inserted in cooperation with the mounting groove and a spring A6 is sleeved on the outer side of the upper end of the sealing rod 2;

[0041] Among them, see Figure 1 and Figure 3The blocking plate 3 is connected to the limiting mechanism, which includes a limiting column 8, an elastic rope 7 and a spring B9; two mounting plates 15 are symmetrically arranged on the end surface of the mounting groove of the blocking plate 3, and the limiting column 8 is inserted in the mounting plate 15. The two limiting columns 8 are arranged opposite to each other and an elastic rope 7 is connected between the two. At the same time, the limiting column 8 is connected to the inner wall of the outer cylinder shell 1 through the spring B9; a blade 11 is provided at the other end of the sealing rod 2, and the blade 11 is arranged directly opposite to the elastic rope 7;

[0042] When cement slurry flows from the flow circular plate 4 to the sealing seat 5, the elastic rope 7, the limit column 8 and the spring B9 limit and fix the blocking plate 3 at the specified position. At this time, there is a certain distance between the sealing rod 2 and the sealing seat 5 (that is, the two are not closed), and the cement slurry can conduct in the reverse direction; when cement slurry flows from the sealing seat 5 to the flow circular plate 4, the sealing rod 2 is pressed downward, so that the blade 11 at the other end of the sealing rod 2 moves toward the elastic rope 7 and cuts off the elastic rope 7. At this time, the limit column 8 retracts to the inner wall of the outer cylinder shell 1 due to the action of the spring B9; after the grouting is stopped at this time, since the elastic rope 7 is cut off, the limit column 8 no longer limits the sealing rod 2, and the umbrella-shaped end of the sealing rod 2 is in close contact with the through hole of the sealing seat 5 due to the rebound of the spring A6, and the two form a closed state.

[0043] The existing cementing casing float collar is usually provided with a one-way valve inside, and has no self-grouting effect. The float collar is not practical and has low efficiency. In addition, the self-grouting float collar designed at present uses a limiting component to limit the sealing valve to achieve the purpose of self-grouting. However, after the self-grouting is completed, since the limiting component is generally arranged at the tail of the sealing valve, it will affect the flow of subsequent cement slurry, or cause the limiting component to be lost or damaged by impact when the cement slurry is poured down. This scheme designs a new self-grouting float collar that is easy to use, and realizes the sealing rod by setting a limiting mechanism on the blocking plate 3. 2, the sealing rod 2 is movably connected to the blocking plate 3, and cooperates with the limiting column 8, the elastic rope 7 and the spring B9 connected to the inner wall of the outer cylinder shell 1. In the initial state, the sealing rod 2 and the sealing seat 5 are separated by a certain distance to achieve reverse conduction. After pressure is applied to the sealing rod 2, the blade 11 at the lower end of the sealing rod 2 cuts off the elastic rope 7, thereby causing the limiting effect to disappear. The limiting column 8 is retracted by the spring B9 and is arranged in contact with the inner wall of the outer cylinder shell 1, which will not affect the subsequent flow of cement slurry. The limiting mechanism of this scheme is simple and practical, and is easy to operate and install.

[0044] In this embodiment, refer to Figure 1 and Figure 2 As for the outer cylinder shell 1, the interior of the outer cylinder shell 1 is hollow, and a sealing seat 5 is arranged on the upper part. The sealing seat 5 is a short cylinder with a through hole in the center. The diameter of the sealing seat 5 is matched with the inner diameter of the outer cylinder shell 1 and the sealing seat 5 is inserted and fixed inside the outer cylinder shell 1.

[0045] In this embodiment, refer to Figure 2 and Figure 3 As for the flow circular plate 4, the flow circular plate 4 is coaxially arranged with the outer cylinder shell 1 and is adaptively inserted and fixed in the middle and lower part of the outer cylinder shell 1. The flow circular plate 4 is separated from the sealing seat 5 by a certain distance. A plurality of flow holes are evenly distributed on the flow circular plate 4 for cement slurry to pass through. A mounting hole is arranged in the center of the flow circular plate 4, and a sealing rod 2 can be movably inserted in the mounting hole.

[0046] In this embodiment, refer to Figure 1-Figure 5 As for the sealing rod 2, the sealing rod 2 includes an umbrella-shaped end and a round rod body connected to the umbrella-shaped end; the sealing rod 2 is coaxially arranged with the outer cylinder shell 1 and the sealing rod 2 can be inserted in the center position of the flow circular plate 4 so as to be movable forward and backward, the umbrella-shaped end of the sealing rod 2 faces the through hole of the sealing seat 5, and a spring A6 is arranged on the outer sleeve of the front half of the rod body of the sealing rod 2, one end of the spring A6 abuts against the umbrella-shaped end, and the other end abuts against the front disk surface of the flow circular plate 4, the tail of the rod body of the sealing rod 2 passes through the flow circular plate 4 and is inserted into the blocking plate 3, and is movably matched with the blocking plate 3.

[0047] In this embodiment, refer to Figure 4 and Figure 6 As for the blocking plate 3, the blocking plate 3 is a circular plate and the diameter of the blocking plate 3 is smaller than the diameter of the flow circular plate 4. The blocking plate 3 is arranged on one side of the rear disc surface of the flow circular plate 4 and is arranged coaxially with the flow circular plate 4 (that is, there is a flow circular plate 4 between the blocking plate 3 and the sealing seat 5). The blocking plate 3 can just block the flow hole on the flow circular plate 4 and can play a sealing role; the center of the blocking plate 3 is opened and a mounting groove is protruded away from the flow circular plate 4. The rear half of the sealing rod 2 passes through the flow circular plate 4 and its tail is inserted into the mounting groove of the blocking plate 3. The mounting groove is provided with The sliding channel 13 is a vertical groove arranged in the installation groove along the axial direction of the installation groove. A plurality of sliding channels 13 are arranged in the installation groove, and a plurality of short protrusions 14 adapted to the vertical groove are protrudingly arranged around the circular side surface of the sealing rod 2 at the tail end of the sealing rod 2. The tail end of the sealing rod 2 can slide along the vertical groove in the installation groove, and a blade 11 is protrudingly arranged on the end surface of the tail end of the sealing rod 2; the lower end surface of the installation groove is sealed and a circular hole is opened in the center of the lower end surface for the blade 11 to extend out. When the sealing rod 2 is compressed and pressed downward, the tail end slides downward in the installation groove, and the blade 11 extends out of the installation groove to cut off the elastic rope 7.

[0048] Furthermore, a plurality of short columns 12 are provided on the end surface of the baffle plate 3 facing the flow circular plate 4, and a plurality of short column 12 grooves are provided on the flow circular plate 4 facing the baffle plate 3, the plurality of short column 12 grooves are opposite to the plurality of short columns 12 on the baffle plate 3, a spring C10 is provided in the short column 12 groove, one end of the spring C10 is connected to the inner bottom surface of the short column 12 groove, and the other end is connected to the end surface of the short column 12 of the baffle plate 3, in the initial state, the limiting mechanism pulls the baffle plate 3 so that the baffle plate 3 and the flow circular plate 4 are separated by a certain distance, and the spring C10 is in a stretched state, which is beneficial to the reverse conduction of the cement slurry, and when the cement slurry is forwardly conducted, the sealing rod 2 is pressed down so that the blade 11 cuts the elastic rope 7 to release the limit, and the spring C10 retracts and resets, and the baffle plate 3 fits with the flow circular plate 4 to play a sealing role.

[0049] Furthermore, the plurality of short column 12 grooves on the flow circular plate 4 are opened at the circumferential edge of the flow circular plate 4 , and the short column 12 grooves and the plurality of flow holes on the flow circular plate 4 do not interfere with each other.

[0050] Furthermore, the blade 11 at the rear end of the sealing rod 2 is set to be conical. When the sealing rod 2 is pressed downward, the blade 11 vertically releases the elastic rope 7 below and cuts it quickly. The overall structure is simple, compact and convenient.

[0051] It should be noted that after the self-grouting float collar is installed and before it is used, the baffle plate 3 needs to be pulled to a position closer to the flow circular plate 4 through the limiting mechanism (that is, to keep the flow holes on the flow circular plate 4 unobstructed) to ensure that after the self-grouting float collar is installed, the baffle plate 3 will not block the flow holes and affect the reverse penetration of the cement slurry.

[0052] It should be noted that after the sealing rod 2 is inserted into the mounting groove of the baffle plate 3, since the holes opened on the upper and lower end faces of the baffle plate 3 are only for the sealing rod 2 to enter and exit, the short protrusion 14 at the tail of the sealing rod 2 is blocked, so that the sealing rod 2 cannot escape from the baffle plate 3, that is, the sealing rod 2 can drive the baffle plate 3 to move. When the limiting effect is released, the sealing rod 2 can drive the baffle plate 3 to move downward each time it is pressed down. The spring C10 is stretched, that is, the short column 12 has been completely pulled out of the short column 12 groove, that is, the short column 12 has been completely bounced out of the flow circular plate 4, the baffle plate 3 is separated from the flow circular plate 4, and the cement slurry can be smoothly poured in.

[0053] In this embodiment, refer to Figure 5 and Figure 7As for the limiting mechanism, two relative mounting plates 15 are vertically protruded from the lower end surface of the mounting groove of the blocking plate 3. The two mounting plates 15 are respectively fixedly connected to the left and right circular side edges of the mounting groove. A mounting hole is opened in the mounting plate 15. The limiting column 8 is inserted into the mounting plate 15 through the mounting hole, so that the two limiting columns 8 are relatively arranged on the blocking plate 3 and are connected by an elastic rope 7. At the same time, grooves 16 are opened on the left and right inner side walls of the outer cylinder shell 1. A spring B9 is connected to each of the left and right grooves 16. The free ends of the left and right springs B9 are respectively connected to the The left and right opposing limiting columns 8 are connected; the grooves 16 provided on the left and right inner walls of the outer cylinder shell 1 are located in the middle and lower part of the outer cylinder shell 1, the spring C10 is connected in the groove 16, the spring C10 is connected to the limiting column 8, the left and right limiting columns 8 are connected by the elastic rope 7, when the floating hoop is installed in the initial state, since the limiting column 8 is inserted into the mounting plate 15, the limiting column 8 pulls the blocking plate 3, the blocking plate 3 is separated from the flow circular plate 4 by a certain distance, and pulls the sealing rod 2, so that the sealing rod 2 is separated from the sealing seat 5 by a certain distance, and the sealing rod 2 and the blocking plate 3 are limited.

[0054] Furthermore, after the blade 11 of the sealing rod 2 cuts the elastic rope 7, the two left and right limit posts 8 are retracted into the grooves 16 of the left and right inner walls of the outer cylinder shell 1 respectively under the resetting and retracting action of the spring C10 to avoid affecting the subsequent flow of cement slurry.

[0055] (Example 2)

[0056] See also Figure 8 and Fig. 9 On the basis of embodiment 1, the limiting mechanism can also adopt another form, that is, the limiting mechanism includes a spring column, a lock tongue 19 and a lock tongue spring 20; the spring seat 17 is a cylindrical shell, the interior of which is hollow, and the spring column is fixedly inserted in the center of the flow circular plate 4 (the two are embedded or threaded or welded), and a long rod 18 is movably inserted in the spring seat 17, and the top end of the long rod 18 is set to a conical end, and the conical end is directly opposite to the through hole of the sealing seat 5, and an elastic member is provided on the outer sleeve of the long rod 18 One end of the elastic member abuts against the conical end, and the other end abuts against the flow circular plate 4. When the long rod 18 is pressed downward by force, the elastic member will contract. When the long rod 18 is not under force, the elastic member stretches and resets, and the conical end abuts against the through hole of the sealing seat 5, and the two are closed; the rod body of the long rod 18 passes through the flow circular plate 4 through the spring seat 17, and the tail of the long rod 18 is fixed to the spring seat 17 through a locking tongue 19. Since the spring seat 17 is fixed to the flow circular plate 4, the long rod 18 is fixed to the flow circular plate 4 through the locking tongue 19 - Changan is fixed and limited.

[0057] Furthermore, the lock tongue 19 is arranged at the tail end of the spring seat 17, and the lock tongue 19 is vertically inserted into the spring seat 17, and penetrates into the tail end of the long rod 18, and abuts against the limit block fixed at the tail end of the long rod 18. A lock tongue spring 20 is sleeved on the lock tongue 19, one end of the lock tongue spring 20 is connected to the outer side of the spring seat 17 shell, and the other end abuts against the tail end of the lock tongue 19. The lock tongue 19 is inserted into the tail end of the long rod 18 toward the spring seat 17 and the long rod 18 is locked and fixed. At this time, the elastic member is compressed, and the tapered end of the long rod 18 is spaced a certain distance from the through hole of the sealing seat 5, that is, the two are not sealed. At the same time, the lock tongue spring 20 is compressed, and the mud flows from the flow circular plate 4 to the sealing seat 5, thereby realizing reverse conduction; when the cement slurry is poured in the forward direction, the long rod 18 is pressed downward, and the lock tongue 19 is driven by the lock tongue spring 20 to retract and withdraw from the long rod 18, and no longer limits the long rod 18. After the grouting is stopped, the lock tongue 19 no longer plays a limiting role.

[0058] Furthermore, a through hole is opened at the corresponding position of the tail of the spring seat 17 and the tail end of the long rod 18, and the lock tongue 19 is inserted into the tail end of the long rod 18 through the through hole; the top of the lock tongue 19 (that is, the position abutting against the limit block at the tail of the long rod 18) is an arc surface and has a groove 16, which abuts against the limit block.

[0059] It should be noted that in Example 2, the locking tongue 19 limiting mechanism cooperates with the long rod 18 that can be extended forward and backward. After the reverse penetration is achieved, the locking tongue 19 becomes invalid, and the long rod 18 cooperates with the spring sleeved on the outside thereof, which can realize the one-way valve function in an orderly and rapid manner. The structure is simple and easy to operate, saving grouting time.

[0060] The present invention discloses a novel self-grouting floating collar which is easy to use. After the self-grouting floating collar in the present invention is installed, two limiting columns 8 inserted at the bottom end of the installation groove of the blocking plate 3 are connected by an elastic rope 7, and the limiting column 8 is connected to the outer cylinder shell 1 by a spring B9. The blocking plate 3 is stretched to a specified position by the limiting mechanism, so that there is a certain distance between the blocking plate 3 and the flow circular plate 4, and between the sealing rod 2 and the sealing seat 5. At this time, cement slurry flows from the flow circular plate 4 to the sealing seat 5, realizing the reverse conduction of cement slurry; when the cement slurry flows from the sealing seat 5 to the flow circular plate 4, the sealing rod 2 is pressed downward by the cement slurry, so that the tail end of the sealing rod 2 is in the installation groove. The sliding path 13 slides downward, and when it slides to the lowest end of the installation groove, the blade 11 at the tail end of the sealing rod 2 extends out of the installation groove and cuts off the elastic rope 7. At this time, the limit columns 8 at the left and right ends are reset and retracted into the inner wall groove 16 at the corresponding position of the outer cylinder shell 1 through the spring B9, and the limit mechanism no longer plays a limiting role; after the grouting is stopped, since it is no longer limited, it is rebounded by the spring A6, and the end of the sealing rod 2 is in contact with the through hole of the sealing seat 5 for sealing. At the same time, the spring C10 retracts, and the blocking plate 3 fits the flow circular plate 4 to play a sealing role; when the cement slurry is poured in again, the sealing rod 2 is pressed downward, and at the same time, the blocking plate 3 is driven to move downward, and the cement slurry can flow from the sealing seat 5 to the flow circular plate 4, playing the role of a one-way valve.

[0061] The casing floating collar used for cementing usually has a one-way valve arranged inside the floating collar, and has no self-grouting effect. This floating collar cannot achieve reverse penetration of cement slurry, is not practical and has low work efficiency. Some floating collars currently designed to achieve self-grouting effect usually have a limiting component arranged at the tail of the sealing valve, and the limiting component is used to limit the sealing valve and the sealing seat 5 to maintain a certain distance to achieve the reverse penetration effect. However, when the subsequent cement slurry flows, the limiting component is easily impacted and lost or damaged. At the same time, the sealing structure in most floating collars is relatively simple, and it is sealed only by spring elastic force. In deep wells, the high temperature and high pressure environment causes the spring to fail, resulting in a decrease in the tightness between the sealing valve core and the grouting channel, which makes it impossible to seal, and ultimately causes leakage and backflow of cement slurry and reduces the quality of cementing. This scheme designs a new self-grouting floating collar, which is more The utility model is easy to use. The sealing rod 2 is limited by the cooperation of the limiting column 8, the elastic rope 7, the spring B9 and the blocking plate 3. When the blade 11 of the sealing rod 2 cuts the elastic rope 7, the limiting column 8 returns to the groove 16 of the inner wall of the outer cylinder shell 1, which will not affect the subsequent flow of cement slurry and will not cause the limiting component to be lost or damaged due to impact. At the same time, the blocking plate 3 is arranged on the lower side of the flow circular plate 4. The blocking plate 3 is movably connected with the sealing rod 2. The blocking plate 3 and the flow circular plate 4 are connected with the spring C10 through the short column 12. The cement slurry is forwardly conducted. After the blade 11 cuts the elastic rope 7 to release the limit, the spring C10 retracts and resets, so that the blocking plate 3 fits with the flow circular plate 4, which can play a sealing role. Together with the sealing rod 2, it has a double sealing effect to avoid leakage and backflow of cement slurry due to sealing failure. The structure of the present scheme is simple and compact, and it is easy to install and use.

[0062] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A new self-grouting floating collar that is easy to use, characterized by: It comprises an outer cylindrical shell (1), a sealing rod (2), a blocking plate (3) and a flow-through circular plate (4); A sealing seat (5) with a through hole is arranged in the middle upper part of the outer cylinder shell (1), a flow circular plate (4) is installed on one side of the sealing seat (5), a plurality of flow holes are arranged on the flow circular plate (4), and a sealing rod (2) is movably inserted in the center of the flow circular plate (4), one end of the sealing rod (2) is located at the through hole of the sealing seat (5), and the sealing rod (2) penetrates the flow circular plate (4) and a blocking plate (3) to be inserted, and a spring A (6) is sleeved on the rod body of the sealing rod (2); The blocking plate (3) is connected to a limiting mechanism, which comprises an elastic rope (7) and a limiting column (8). The two limiting columns (8) are arranged opposite to each other and are connected via the elastic rope (7). The two limiting columns (8) are connected to the left and right inner walls of the corresponding outer cylinder shell (1) via a spring B (9). The other end of the sealing rod (2) faces the elastic rope (7) and a blade (11) is arranged at the end to cut the elastic rope (7). When cement slurry flows from the flow circular plate (4) to the sealing seat (5), the blocking plate (3) and the sealing rod (2) are fixed via the limiting mechanism, and the sealing rod (2) and the sealing seat (5) are not sealed, thereby realizing reverse conduction of cement slurry; when cement slurry flows from the sealing seat (5) to the flow circular plate (4), the spring A (6) is compressed, and the sealing rod (2) presses down the blade (11) at its end to cut the elastic rope (7), so that the limiting column (8) retracts via the spring B (9); after the grouting stops, the limiting mechanism no longer limits, and a closed state is formed between the sealing rod (2) and the sealing seat (5).

2. A novel self-grouting floating collar that is easy to use according to claim 1, characterized in that: The blocking plate (3) is provided with a plurality of short columns (12) on the end surface facing the flow circular plate (4); the flow circular plate (4) is provided with a plurality of short column (12) grooves corresponding to the plurality of short columns (12); a spring C (10) is arranged in the short column (12) groove, and the spring C (10) is connected to the short column (12); the blocking plate (3) is pulled by a limiting mechanism so that the blocking plate (3) and the flow circular plate (4) are separated by a certain distance, which is conducive to reverse conduction of cement slurry; after the sealing rod (2) is pressed down and the blade (11) cuts the elastic rope (7), the blocking plate (3) is fitted with the flow circular plate (4) through the spring C (10) to form a sealing state.

3. A novel self-grouting floating collar that is easy to use according to claim 2, characterized in that: The plurality of short column (12) grooves are arranged on the circumferential edge of the flow circular plate (4) and do not interfere with the plurality of flow holes on the flow circular plate (4).

4. A novel self-grouting floating collar that is easy to use according to claim 2, characterized in that: The blocking plate (3) has an installation groove on its end surface facing away from the flow-through circular plate (4), the sealing rod (2) is inserted into the installation groove and a sliding path (13) is provided between the sealing rod (2) and the installation groove, the sealing rod (2) can move along the sliding path (13) and extend the end blade (11) to cut the elastic rope (7).

5. A novel self-grouting floating collar that is easy to use according to claim 1, characterized in that: The spring A (6) is sleeved outside the rod body of the sealing rod (2), and one end of the spring A (6) abuts against the lower side of the umbrella-shaped end of the sealing rod (2), and the other end abuts against the end surface of the flow-through circular plate (4).

6. A novel self-grouting floating collar that is easy to use according to claim 4, characterized in that: The sliding channels (13) are multiple vertical grooves opened inside the installation groove, and the lower part of the sealing rod (2) is provided with a short protrusion (14) adapted to the vertical groove, and the bottom end surface of the installation groove blocks the short protrusion (14).

7. A novel self-grouting floating collar that is easy to use according to claim 6, characterized in that: Two mounting plates (15) are arranged opposite to each other at the lower end of the mounting groove. The mounting plates (15) are provided with holes, and the limiting columns (8) are inserted into the holes. The two limiting columns (8) are arranged opposite to each other and an elastic rope (7) is connected between the two. A groove (16) is provided on the inner side wall of the outer cylinder shell (1) at a position opposite to the limiting columns (8). After the elastic rope (7) is cut off, the spring B (9) retracts the limiting column (8) into the groove (16) to avoid blocking the cement slurry.

8. A novel self-grouting floating collar that is easy to use according to claim 1, characterized in that: The limiting mechanism comprises a spring seat (17), a locking tongue (19), and a locking tongue spring (20); the spring seat (17) is inserted and fixed at the center of the flow circular plate (4); a long rod (18) is movably inserted in the spring seat (17); an elastic member is sleeved on the long rod (18); the end of the long rod (18) faces the through hole of the sealing seat (5) and the tail of the long rod (18) passes through the flow circular plate (4) through the spring seat (17); the long rod (18) is limited by the locking tongue (19) and the spring seat (17); the locking tongue (19) is arranged at the tail end of the spring seat (17) and is vertically inserted into the spring seat (17) and the tail of the long rod (18); a locking tongue spring (20) is sleeved on the locking tongue (19); one end of the locking tongue spring (20) abuts against the outer side of the spring seat (17) and the other end abuts against the end of the locking tongue (19); The lock tongue (19) is inserted into the spring seat (17) and locked at the tail of the long rod (18). At this time, the lock tongue spring (20) is compressed, the long rod (18) and the sealing seat (5) are not sealed, and the cement slurry can flow from the flow circular plate (4) to the sealing seat (5) to achieve reverse conduction; when the cement slurry is forwardly conducted, the long rod (18) is pressed down, the lock tongue (19) retracts and exits the long rod (18), and the lock tongue spring (20) is not compressed; after the grouting is stopped, the lock tongue (19) is no longer limited, and the long rod (18) and the sealing seat (5) are sealed.

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