A type of floating hoop and float shoe for deep well cementing

Abstract

This invention relates to the field of cementing engineering tools, and discloses a floating hoop and float shoe for deep well cementing, comprising: a floating hoop, casing, float shoe, and guide cap connected in sequence by threads; the floating hoop is provided with a first one-way feeding unit, and the float shoe is provided with a second one-way feeding unit with the same structure as the first one-way feeding unit; the first one-way feeding unit includes: a fixedly set skirt structure: the top sealing plate is a trumpet-shaped gradually expanding cone surface, and the bottom sealing plate is a trumpet-shaped gradually contracting cone surface, both of which are coaxially fixed in the floating hoop. In this application, the central sealing ball, the edge sealing ball, and the reverse pushing ball are linked by a mechanical linkage, and the three channels are synchronously locked within 0.5s after the grouting ends to prevent cement slurry backflow. When the bottom hole back pressure is >5MPa, the reverse sealing component triggers the reconstruction of the spherical sealing surface, driving the central sealing ball and the edge sealing ball to increase the additional clamping force, and withstands an extreme back pressure of 105MPa.

Description

Technical Field

[0001] This invention relates to the field of cementing engineering tools, specifically to a floating hoop and float shoe for deep well cementing. Background Technology

[0002] In oil and gas well cementing operations, float collars and float shoes are crucial components. They are typically installed at the bottom of the casing string, and their main function is to allow cement slurry to pass smoothly during grouting and to quickly close the passage after grouting to prevent cement slurry from flowing back into the casing, ensuring the integrity of the cement sheath within the annulus and thus guaranteeing the long-term stability and safety of the wellbore.

[0003] Traditional float collars and float shoes mostly employ a one-way valve structure. These valves rely on spring preload or gravity to open and close. Specifically, during the grouting stage, because the pressure of the cement slurry is greater than the downhole back pressure, the one-way valve automatically opens, allowing the cement slurry to flow smoothly into the annular space. After grouting is completed, when the pumping pressure disappears, the one-way valve quickly closes under the action of the spring to prevent the cement slurry from flowing back into the casing. This design is simple and effective and is widely used in conventional cementing operations.

[0004] While traditional floats and hoop shoes meet basic cementing requirements to some extent, their limitations are becoming increasingly apparent with increasing exploration depth and complex geological conditions: Insufficient reliability due to a single sealing structure: Most traditional floats and hoop shoes rely on only one check valve or ball valve for sealing. Under high pressure differentials or in the presence of impurities, this single sealing method is prone to leakage or jamming, affecting the sealing effect; Slow sealing response: Due to the lack of an effective synchronization mechanism, existing floats and hoop shoes cannot immediately complete the full closure of the channel at the end of grouting, which may lead to some cement slurry backflow, affecting not only cementing quality but also subsequent construction difficulties; Limited resistance to extreme back pressure: Faced with abnormally high pressures at the bottom of the well (e.g., formation back pressure exceeding 5 MPa), traditional designs often lack sufficient adaptive adjustment capabilities. In such cases, the sealing surface may be ruptured by the high pressure, making it difficult to withstand extreme back pressures up to 105 MPa, posing safety hazards to downhole operations; Lack of a linkage mechanism: In current designs, the closure of the central channel, edge channel, and bottom channel is usually operated independently, without forming an effective linkage system. This means that in actual operation, the channels cannot be closed at the same time, which can easily lead to local erosion and further increase the risk of seal failure.

[0005] In summary, while traditional floatation rings and shoes can accomplish basic tasks under certain conditions, existing technologies still have significant room for improvement in addressing more complex geological environments and higher safety standards. To overcome these challenges, a more intelligent and efficient solution is needed to improve sealing performance, accelerate response speed, and enhance adaptability to extreme operating conditions. Summary of the Invention

[0006] The purpose of this invention is to provide a float band and float shoe for deep well cementing, so as to solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a floatation collar and float shoe for deep well cementing, comprising:

[0008] The floating collar, sleeve, floating shoe, and guide cap are connected in sequence by threads;

[0009] The float hoop is provided with a first one-way feeding unit, and the float shoe is provided with a second one-way feeding unit with the same structure as the first one-way feeding unit.

[0010] The first unidirectional feeding unit includes:

[0011] Fixed skirt structure: The top sealing plate is a flared, gradually expanding cone surface, and the bottom sealing plate is a flared, gradually contracting cone surface. The two are coaxially fixed inside the floating hoop.

[0012] Central sealing assembly: a central ball rod that runs through the bottom sealing plate, with a central sealing ball fixed at its top and corresponding to the central flow channel of the top sealing plate. A central telescopic plate is fitted over the central ball rod, and a central jacket layer is formed between the two to accommodate the first main spring.

[0013] Edge sealing assembly: Several edge balls surrounding the central ball, with an edge sealing ball fixed at the top and corresponding to the edge flow channel of the top sealing plate. An edge telescopic plate is fitted over the edge ball, and an edge jacket layer that accommodates the second main spring is formed between the two.

[0014] Reverse sealing assembly: The top of the reverse cue assembly is connected to both the central telescopic plate and the edge telescopic plate via a connecting rod, while the bottom of the assembly passes through the bottom flow channel of the bottom sealing plate and fixes the reverse push ball.

[0015] According to the above technical solution, the reverse cue assembly includes:

[0016] The club is fixed at the top to the connecting rod and at the bottom to the movable plate.

[0017] The nested movable rod is movably fitted outside the fixed cue stick, with the bottom fixed to push the ball in the opposite direction, and its outer wall forms an indented area with a diameter smaller than the bottom flow channel.

[0018] According to the above technical solution, a movable cavity is opened at the bottom of the reverse ball pusher, and a matching limiting plate is provided at the bottom of the movable cavity evenly distributed around the circumference;

[0019] The bottom of the movable plate is provided with a matching limiting groove corresponding to the matching limiting plate;

[0020] The nested movable rod has a lifting cavity inside, and a fixed plate is fixedly sleeved on the fixed ball rod. A return spring is provided between the fixed plate and the top of the lifting cavity.

[0021] When the movable plate descends to the bottom of the movable cavity, a compensation gap is formed between the two; when the back pressure in the well exceeds the threshold, the movable plate moves up to make the fitting limiting groove fit into the fitting limiting plate, forming a continuous sealing surface.

[0022] According to the above technical solution, the central telescopic plate and the edge telescopic plates have the same structure and similar functions, and the central telescopic plate includes:

[0023] A central fixing base fixed to the bottom sealing plate;

[0024] A lifting and movable sleeve is fitted outside the central cue stick. Its inner wall is provided with a lifting and sliding cavity. The top of the central fixed base extends into the lifting and sliding cavity and is fixedly installed with a lifting and sliding plate.

[0025] The auxiliary spring located in the lifting slide cavity has its two ends abutting against the lifting movable sleeve and the central fixed base, respectively.

[0026] According to the above technical solution, the central fixed base of the central telescopic plate extends to form a double straight gradually expanding conical surface guide section, which extends to the bottom flow channel inlet to guide the cement slurry to flow into the flow channel.

[0027] The edge fixing base of the edge telescopic plate is a straight cylindrical structure, and its outer wall is flush with the conical surface of the bottom sealing plate to form a continuous guide surface.

[0028] According to the above technical solution, the edges of the central flow channel, the edge flow channel and the bottom flow channel are all polished with rounded corners of R0.5-R1mm;

[0029] The inner walls of the central flow channel, edge flow channel and bottom flow channel are all covered with a 200-300μm tungsten carbide wear-resistant layer.

[0030] The outer surfaces of both the top and bottom sealing plates are covered with a 150-200μm tungsten carbide wear-resistant layer.

[0031] According to the above technical solution, a first spherical sealing groove is provided at one end of the central flow channel that contacts the central sealing ball, and a first silicon carbide sealing ring is embedded in the edge of the first spherical sealing groove to form a first spherical sealing groove.

[0032] The edge flow channel is provided with a second spherical sealing groove at one end that contacts the edge sealing ball, and a second silicon carbide sealing ring is embedded at the edge of the second spherical sealing groove.

[0033] The bottom flow channel is provided with a third spherical sealing groove at the end that contacts the reverse push ball, and a third silicon carbide sealing ring is inlaid on the edge of the third spherical sealing groove.

[0034] According to the above technical solution, the central flow channel is located in the central plane area of ​​the top sealing plate;

[0035] The edge flow channels are located in the conical area of ​​the top sealing plate and are evenly distributed along the circumference of the conical surface;

[0036] The bottom flow channel is located in the transition area between the conical surface and the plane of the bottom sealing plate, and is ≤10mm from the plane boundary;

[0037] A first honeycomb-shaped rectifier grille is disposed above the planar area of ​​the top sealing plate;

[0038] A second honeycomb-shaped rectifier grille is provided in the conical area of ​​the top sealing plate.

[0039] According to the above technical solution, the first honeycomb rectifier grille is embedded in the central flow channel inlet section in a layered nesting manner, including a honeycomb rectifier layer and a spiral guide layer from top to bottom.

[0040] The second honeycomb rectifier grille is embedded into the edge flow channel inlet through a conical bonding structure, and a shape memory alloy heat compensation ring is set between the two.

[0041] The embedding depth of both the first and second honeycomb rectifier grilles does not exceed 1 / 3 of the total length of the corresponding channel.

[0042] According to the above technical solution, the outer walls of the central sealing ball, the edge sealing ball, and the reverse pushing ball are all covered with double-layer sealing sleeves:

[0043] The inner layer is a 1.5-2mm hydrogenated nitrile rubber layer;

[0044] The outer layer is a 0.5-1mm compressible expandable graphite layer.

[0045] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0046] (1) Multi-level linkage sealing performance improvement: Triple sealing synergy: The central sealing ball, edge sealing ball and reverse push ball are linked by mechanical linkage. The three channels are locked synchronously within 0.5s when the grouting ends, preventing cement slurry backflow; Adaptive reinforcement of back pressure: When the bottom back pressure is >5MPa, the reverse sealing component triggers the reconstruction of the spherical sealing surface, driving the central sealing ball and edge sealing ball to increase the additional clamping force, and withstand the extreme back pressure of 105MPa.

[0047] (2) Improved adaptability to extreme working conditions: High pressure sealing stability: The linear sealing design of the central sealing ball and silicon carbide sealing ring, combined with the preload of the first main spring and the linkage boosting mechanism of the connecting rod, can still maintain a contact pressure of 126MPa under reverse pressure (105MPa), achieving zero leakage sealing; High temperature environment resistance: The shape memory alloy thermal compensation ring expands by 0.15mm at 150℃, accurately compensating for thermal deformation gaps and avoiding sealing failure caused by thermal stress. The expanded graphite layer expands at high temperature to fill micro-defects and maintain the integrity of the seal; Corrosion and abrasion protection: All inner walls of the flow channels and outer surfaces of the sealing plates are covered with a 200-300μm tungsten carbide wear-resistant layer with a hardness close to 9 Mohs. The wear resistance is 3 times higher than that of traditional hard chrome plating. The chemical inertness of the tungsten carbide coating effectively resists corrosion and abrasion. , It can withstand corrosive media and extend the equipment's lifespan by more than 5 times.

[0048] (3) Fluid control optimization: The first honeycomb rectifier grid (planar area) eliminates inlet turbulence and reduces local resistance loss through the honeycomb rectifier layer and spiral guide layer. The second honeycomb rectifier grid (conical area) corrects the fluid direction through the conical fitting structure, reduces vortex and backflow, and improves injection efficiency by 25%. The R0.5-R1mm rounded corner polishing of the channel edge further reduces fluid friction resistance and ensures uniform distribution of cement slurry.

[0049] (4) Redundancy and long life design of sealing system: Multiple sealing topology: Metal-silicon carbide-metal triple seal: The central sealing ball and silicon carbide ring form a rigid line seal, the hydrogenated nitrile rubber layer provides elastic buffering, the expanded graphite layer fills micro-defects, single-point failure does not affect the overall sealing performance, the auxiliary spring assists the seal, and can still maintain the sealing pressure when the main spring fails, improving safety by 90%; Fatigue resistance and long cycle operation: The lifting and lowering sleeve of the central telescopic plate provides elastic buffering through the auxiliary spring, with a theoretical life ≥ After one operating cycle, the shape memory alloy material can withstand... It can withstand repeated thermal cycles without failure and adapt to frequent start-up and shutdown conditions in deep wells.

[0050] (5) Improved engineering life and reliability: The central telescopic plate and the edge telescopic plate protect the first and second main springs throughout the process. The tool can be used 62 times (traditional tools ≤ 23 times). The first honeycomb rectifier grid and the second honeycomb rectifier grid form a filtration system to protect the sealing components from wear. The smooth surface of the tungsten carbide coating (Ra≤0.8μm) combined with the fluid pulsation effect can automatically remove attached particles and reduce the risk of blockage.

[0051] (6) Optimization of maintenance costs and economic benefits: Reduce downtime maintenance frequency: The tungsten carbide wear-resistant layer extends the service life of the equipment to 2-3 years in harsh environments such as mines and oil fields (traditional equipment requires monthly maintenance), saving more than RMB 2 million in maintenance costs annually. The self-cleaning design reduces the need for manual cleaning and improves the continuity of operations; Improve operation efficiency: The dual-stage rectifier grid increases the cement slurry injection efficiency by 25%, shortens the cementing operation time, extends the service life of sealing components by 70%, reduces the frequency of spare parts replacement, and reduces operating costs. Attached Figure Description

[0052] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0053] Figure 1 This is a first perspective view of the present invention;

[0054] Figure 2 This is a second perspective view of the present invention;

[0055] Figure 3 This is an exploded view of the present invention;

[0056] Figure 4 This is a first partial three-dimensional schematic diagram of the present invention;

[0057] Figure 5 This is a second partial perspective view of the present invention;

[0058] Figure 6 This is a third partial perspective view of the present invention;

[0059] Figure 7 This is a fourth partial perspective view of the present invention;

[0060] Figure 8 This is a fifth partial perspective view of the present invention;

[0061] Figure 9 This is a sixth partial perspective view of the present invention;

[0062] Figure 10 This is a third-dimensional schematic diagram of the seventh part of the present invention;

[0063] Figure 11 This is the eighth partial perspective view of the present invention;

[0064] Figure 12 This is a third-dimensional schematic diagram of the ninth part of the present invention;

[0065] Figure 13 This is a three-dimensional schematic diagram of the tenth part of the present invention;

[0066] Figure 14 This is the eleventh partial perspective view of the present invention;

[0067] Figure 15 This is a twelfth partial perspective view of the present invention;

[0068] In the diagram: 1-Floating hoop, 2-Sleeve, 3-Floating shoe, 4-Guide cap, 5-First unidirectional feeding unit, 51-Skirt structure, 511-Top sealing plate, 5111-Central flow channel, 5112-Edge flow channel, 512-Bottom sealing plate, 5121-Bottom flow channel, 52-Bottom sealing plate, 521-Central ball rod, 522-Central sealing ball, 523-Central telescopic plate, 5231-Central fixed base, 5232-Lifting movable sleeve, 5233-Lifting slide cavity, 5234-Secondary spring, 5235-Double straight gradually expanding conical guide section, 5236-Lifting slide plate, 524-First main spring, 53-Edge sealing assembly, 531-Edge ball rod, 532-Edge sealing ball, 533-Edge telescopic plate, 5331-Edge fixed base. 534-Second main spring, 54-Reverse sealing assembly, 541-Connecting rod, 542-Reverse push ball, 5421-Moving cavity, 543-Fixed ball rod, 544-Moving plate, 5441-Matching limiting groove, 545-Nested moving rod, 5451-Lifting cavity, 546-Concave area, 547-Matching limiting plate, 548-Fixed plate, 549-Reset spring, 601-First spherical sealing groove, 602-First silicon carbide sealing ring, 603-Second spherical sealing groove, 604-Second silicon carbide sealing ring, 605-Third spherical sealing groove, 606-Third silicon carbide sealing ring, 701-First honeycomb rectifier grid, 702-Second honeycomb rectifier grid, 801-Hydrogenated nitrile rubber layer, 802-Compressible expandable graphite layer, 9-Second unidirectional feeding unit. Detailed Implementation

[0069] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0070] Please see Figure 1-15 The present invention provides a technical solution: a floating hoop and float shoe for deep well cementing, comprising:

[0071] The floating hoop 1, sleeve 2, floating shoe 3, and guide cap 4 are connected in sequence by threads;

[0072] The floating hoop 1 is provided with a first one-way feeding unit 5, and the floating shoe 3 is provided with a second one-way feeding unit 9 with the same structure as the first one-way feeding unit 5.

[0073] The first unidirectional feeding unit 5 includes:

[0074] The fixed skirt structure 51 has a top sealing plate 511 with a gradually expanding cone shape and a bottom sealing plate 512 with a gradually contracting cone shape. The two are coaxially fixed in the floating hoop 1.

[0075] Central sealing assembly 52: a central ball rod 521 that passes through the bottom sealing plate 512, with a central sealing ball 522 fixed at its top and corresponding to the central flow channel 5111 of the top sealing plate 511. A central telescopic plate 523 is fitted over the central ball rod 521, and a central jacket layer is formed between the two to accommodate the first main spring 524.

[0076] Edge sealing assembly 53: a plurality of edge rods 531 surrounding the central rod 521, with an edge sealing ball 532 fixed at its top and corresponding to the edge flow channel 5112 of the top sealing plate 511. An edge telescopic plate 533 is fitted over the edge rods 531, and an edge jacket layer for accommodating the second main spring 534 is formed between the two.

[0077] Reverse sealing assembly 54: The top of the reverse cue assembly is connected to the central telescopic plate 523 and the edge telescopic plate 533 simultaneously via the connecting rod 541, and the bottom passes through the bottom flow channel 5121 of the bottom sealing plate 512 and fixes the reverse push ball 542.

[0078] Specifically, the reverse cue assembly includes:

[0079] The fixed cue stick 543 is fixed at the top to the connecting rod 541 and at the bottom to the movable plate 544;

[0080] The nested movable rod 545 is movably sleeved outside the fixed ball rod 543, with the bottom fixed to the reverse push ball 542, and its outer wall forms an inner concave area 546 with a diameter smaller than the bottom flow channel 5121;

[0081] Specifically, the bottom of the reverse ball pusher 542 has a movable cavity 5421, and the bottom of the movable cavity 5421 is provided with a circumferentially distributed fitting limiting plate 547.

[0082] The bottom of the movable plate 544 is provided with a matching limiting groove 5441 corresponding to the matching limiting plate 547;

[0083] The nested movable rod 545 is provided with a lifting cavity 5451, and a fixed plate 548 is fixedly sleeved on the fixed ball rod 543. A return spring 549 is provided between the fixed plate 548 and the top of the lifting cavity 5451.

[0084] When the movable plate 544 descends to the bottom of the movable cavity 5421, a compensation gap is formed between the two; when the back pressure in the well exceeds the threshold, the movable plate 544 moves upward so that the fitting limiting groove 5441 fits into the fitting limiting plate 547 to form a continuous sealing surface.

[0085] The reverse ball-and-stick assembly is the core sealing and dynamic response mechanism of this device, and its functional design aims to achieve the following objectives:

[0086] 1. Enhanced sealing under high-pressure reverse operating conditions:

[0087] Sealing trigger mechanism:

[0088] When the back pressure in the well exceeds a preset threshold (e.g., 5MPa), the reverse push ball 542 is pushed by the fluid pressure, overcomes the preload of the reset spring 549, and drives the movable plate 544 upward.

[0089] Formation of continuous sealing surfaces:

[0090] When the movable plate 544 moves to its limit position, the reverse push ball 542 engages with the matching limiting plate 547, filling the dynamic sealing gap and forming a complete spherical seal (radius of curvature R=15mm), and directly sealing the inlet of the bottom flow channel 5121.

[0091] The sealing strength is doubled:

[0092] Under extreme conditions (such as 105MPa back pressure), the contact pressure between the reverse push ball 542 and the third silicon carbide sealing ring 606 can reach 126MPa. The plastic flow of the expanded graphite layer 802 further fills the micro-defects, achieving zero leakage.

[0093] 2. Dynamic linkage control of the clamping force of the central / edge sealing components:

[0094] Mechanical linkage supercharging mechanism

[0095] Linkage drive principle:

[0096] The up-and-down movement of the movable plate 544 is transmitted to the central telescopic plate 523 and the edge telescopic plate 533 through the connecting rod 541, forming a linkage boosting effect.

[0097] Additional clamping force calculation (the additional clamping forces of the central sealing ball 522 and the edge sealing ball 532 are different. The central sealing ball 522 is connected by a short lever arm, while the edge sealing ball 532 is connected by a long lever arm, forming an asymmetric lever system. The central flow channel 5111 bears the main flow and needs to be sealed first. The flow of the edge flow channel 5112 is distributed to multiple balls, and the additional force requirement of a single ball is reduced):

[0098] Central sealing ball 522:

[0099] Additional clamping force =1.2 × back pressure (e.g., when the back pressure is 10 MPa) =12MPa).

[0100] Edge sealing ball 532:

[0101] Additional clamping force =0.8 × back pressure ( =8MPa).

[0102] Improved sealing stability:

[0103] Through coordinated pressurization, the contact pressure between the central / edge sealing ball and the corresponding sealing groove is significantly increased, ensuring that there is no slippage or leakage on the sealing surface under high-pressure reverse operating conditions.

[0104] Flow control in concave region 546

[0105] Dynamic alignment design:

[0106] During the cement slurry injection stage, the nested movable rod 545 moves down, and the concave area 546 is precisely aligned with the bottom flow channel 5121 to form a trapezoidal flow section (maximum opening width 2.5mm) to optimize fluid distribution.

[0107] Reverse shutdown protection:

[0108] When the reverse push ball 542 moves upward, the concave area 546 disengages from the bottom flow channel 5121, avoiding wear caused by reverse fluid scouring.

[0109] 3. Multi-stage sealing topology optimization and failure redundancy design:

[0110] Limiting interlocking structure

[0111] After the matching limiting groove 5441 of the movable plate 544 is fitted with the matching limiting plate 547, a continuous spherical sealing surface is formed, eliminating the sealing gap.

[0112] Redundancy design:

[0113] Even if a local sealing surface fails due to wear or impurities, the overall sealing surface after fitting can still maintain sealing performance, avoiding system collapse caused by single-point failure.

[0114] Compensation function of movable cavity 5421

[0115] Micro-permeability control:

[0116] The movable cavity 5421 at the bottom of the reverse push ball 542 allows a small amount of fluid to seep out (flow rate < 0.5 L / min), avoiding mechanical damage caused by stress concentration in the sealing.

[0117] Self-cleaning function:

[0118] Seepage can remove impurities and particles between sealing surfaces, reducing the risk of wear during long-term use.

[0119] Specifically, the central telescopic plate 523 and the edge telescopic plate 533 have the same structure and similar functions. The central telescopic plate 523 includes:

[0120] The central fixing base 5231 is fixed to the bottom sealing plate 512;

[0121] A lifting movable sleeve 5232 is fitted outside the central cue 521, and a lifting slide cavity 5233 is provided on its inner wall. The top of the central fixed base 5231 extends into the lifting slide cavity 5233 and is fixedly installed with a lifting slide plate 5236.

[0122] The auxiliary spring 5234, located in the lifting slide cavity 5233, abuts against the lifting movable sleeve 5232 and the central fixed base 5231 at its two ends respectively.

[0123] The central telescopic plate 523 is the core motion and sealing control component of this device, and its functional design aims to achieve the following objectives:

[0124] 1. Dynamic sealing and channel control

[0125] Sealing effect in the initial closed state

[0126] Main spring preload mechanism:

[0127] The first main spring 524 applies preload through the central fixed base 5231 of the central telescopic plate 523, pushing the central ball rod 521 to drive the central sealing ball 522 to tightly adhere to the first spherical sealing groove 601 (with the first silicon carbide sealing ring 602 embedded). At this time, the central sealing ball 522 and the first spherical sealing groove 601 form a line seal (contact width 0.25mm), and the sealing pressure is directly transmitted by the spring preload.

[0128] Secondary spring auxiliary mechanism:

[0129] The auxiliary spring 5234 is in a compressed state and transmits force upward through the sliding cavity 5233 of the lifting movable sleeve 5232, which helps the central sealing ball 522 maintain a seal even when the spring preload fails (such as local wear).

[0130] Channel opening during cement grout injection stage

[0131] Pressure burst response:

[0132] When the cement slurry pressure overcomes the preload of the first main spring 524, the central sealing ball 522 moves down along the central ball rod 521 and separates from the first spherical sealing groove 601, forming an annular flow gap (0.5-1.2mm in diameter), opening the central flow channel 5111.

[0133] Fluid rectification optimization:

[0134] The double-straight gradually expanding conical guide section 5235 of the central telescopic plate 523 guides the fluid to the inlet of the bottom flow channel 5121, reducing local resistance loss and avoiding fluid turbulence separation.

[0135] 2. Protect the main spring and sealing components from abrasion.

[0136] Isolate mud from corrosive media

[0137] Telescopic partition isolation design:

[0138] During the cement slurry injection stage, the central telescopic plate 523 moves down through the sliding cavity 5233 of the lifting movable sleeve 5232, isolating the main spring 524 from contact with the slurry and preventing spring corrosion.

[0139] Material durability:

[0140] The central telescopic plate 523 is made of high wear-resistant alloy steel (with a 200-300μm tungsten carbide wear-resistant layer on the surface) to ensure long-term stable operation under high pressure and high temperature environments.

[0141] Sealing component protection

[0142] Silicon carbide sealing ring 602:

[0143] It is resistant to high temperatures (≤300℃) and wear (friction coefficient ≤0.01), and maintains rigid sealing properties under high pressure.

[0144] 3. Coordinate the movement of the edge / bottom sealing components.

[0145] Linkage drive mechanism

[0146] The downward movement of the central cue 521 transmits power to the reverse sealing assembly 54 through the connecting rod 541, pushing the nested movable rod 545 downward, so that the concave area 546 is precisely aligned with the bottom flow channel 5121, forming a trapezoidal flow section (maximum opening width 2.5mm).

[0147] Edge sealing assembly synchronous control

[0148] The central telescopic plate 523 and the edge telescopic plate 533 are linked by the connecting rod 541 to ensure the synchronous opening and closing of the central sealing ball 522 and the edge sealing ball 532, and to avoid sealing imbalance caused by unilateral movement.

[0149] Specifically, the central fixed base 5231 of the central telescopic plate 523 extends to form a double straight gradually expanding conical surface guide section 5235, which extends to the inlet of the bottom flow channel 5121 to guide the cement slurry to flow into the flow channel.

[0150] The edge fixing base 5231 of the edge telescopic plate 533 is a straight cylindrical structure, and its outer wall is flush with the conical surface of the bottom sealing plate 512 to form a continuous guide surface.

[0151] Specifically, the edges of the central flow channel 5111, the edge flow channel 5112, and the bottom flow channel 5121 are all polished with rounded corners of R0.5-R1mm;

[0152] The inner walls of the central flow channel 5111, the edge flow channel 5112 and the bottom flow channel 5121 are all covered with a 200-300μm tungsten carbide wear-resistant layer.

[0153] The outer surfaces of the top sealing plate 511 and the bottom sealing plate 512 are both covered with a 150-200μm tungsten carbide wear-resistant layer.

[0154] The rounded corner design (R0.5-R1mm) eliminates sharp angles at the channel edges, reducing turbulence and separation during fluid flow. The rounded transition allows for smoother fluid flow, preventing sudden velocity changes due to abrupt changes in direction and ensuring uniform fluid distribution to downstream equipment. The rounded corner area also reduces the direct impact of hard particles (such as gravel and carbides) on the channel walls, lowering the rate of localized wear. Tungsten carbide has a hardness close to 9 Mohs, significantly higher than that of metal substrates (such as stainless steel, which has a hardness ≤4 Mohs). Tungsten carbide (TMC) coatings effectively resist abrasive wear from gravel and hard particles. Under high-pressure fluid conditions (e.g., 105 MPa) or high-frequency vibration environments, the TMC coating absorbs localized stress, preventing substrate failure due to fatigue crack propagation. In acidic / alkaline environments, TMC forms a dense oxide film, preventing corrosive media from penetrating the substrate and extending channel life. The low surface roughness (Ra≤0.8μm) of the TMC coating reduces the probability of impurities (e.g., mud particles) adhering to the fluid, minimizing the risk of blockage. Through the synergistic effect of rounded corner polishing and the TMC coating, channels and sealing components function effectively under high pressure, high temperature, and corrosive media (e.g., containing...). , In muddy environments, it can operate continuously for more than 1,000 hours without failure, reducing the frequency of downtime maintenance (traditional hard chrome plating requires monthly maintenance, while tungsten carbide coating can extend to 2-3 years).

[0155] Specifically, a first spherical sealing groove 601 is provided at one end of the central flow channel 5111 that contacts the central sealing ball 522, and a first silicon carbide sealing ring 602 is embedded in the edge of the first spherical sealing groove 601.

[0156] The edge flow channel 5112 is provided with a second spherical sealing groove 603 at one end that contacts the edge sealing ball 532, and a second silicon carbide sealing ring 604 is embedded at the edge of the second spherical sealing groove 603.

[0157] The bottom flow channel 5121 is provided with a third spherical sealing groove 605 at the end that contacts the reverse push ball 542, and a third silicon carbide sealing ring 606 is inlaid on the edge of the third spherical sealing groove 605.

[0158] Specifically, the central flow channel 5111 is located in the central plane area of ​​the top sealing plate 511;

[0159] The edge flow channel 5112 is located in the conical area of ​​the top sealing plate 511 and is evenly distributed along the circumference of the conical surface;

[0160] The bottom flow channel 5121 is located in the transition area between the conical surface and the plane of the bottom sealing plate 512, and is ≤10mm from the plane boundary;

[0161] A first honeycomb-shaped rectifier grille 701 is provided above the planar area of ​​the top sealing plate 511;

[0162] A second honeycomb-shaped rectifier grille 702 is provided in the conical area of ​​the top sealing plate 511;

[0163] Specifically, the first honeycomb rectifier grille 701 is embedded in the inlet section of the central flow channel 5111 in a layered nesting manner, including a honeycomb rectifier layer and a spiral guide layer from top to bottom;

[0164] The second honeycomb rectifier grille 702 is embedded into the inlet of the edge flow channel 5112 through a conical bonding structure, and a shape memory alloy heat compensation ring is provided between the two.

[0165] The embedding depth of both the first honeycomb rectifier grille 701 and the second honeycomb rectifier grille 702 does not exceed 1 / 3 of the total length of the corresponding channel;

[0166] The first honeycomb rectifier grille 701 and the second honeycomb rectifier grille 702 are fluid rectification devices composed of hexagonal honeycomb structures. Their core function is to optimize fluid flow characteristics through geometric structure, featuring low flow resistance, high stability, and strong impact resistance. The first honeycomb rectifier grille 701 is embedded above the planar area of ​​the top sealing plate 511, located at the inlet section of the central flow channel 5111. It adopts a layered nested structure, including a honeycomb rectification layer and a spiral guide layer from top to bottom. The honeycomb rectification layer is composed of hexagonal channels with a diameter of 0.8-1.2mm, used for initial fluid rectification and pressure equalization. The spiral guide layer guides the fluid to rotate axially through spiral channels, enhancing fluid uniformity and reducing turbulence separation. The embedding depth does not exceed 1 / 3 (approximately 10-15mm) of the total length of the central flow channel 5111 to avoid excessive compression of the flow channel leading to increased pressure loss. The second honeycomb rectifier grille 702 is embedded in the top sealing plate 511. The conical area of ​​the sealing plate 511 connects to the inlet of the edge flow channel 5112. It adopts a conical fitting structure, and the honeycomb channel is matched with the angle of the conical surface (30°-45°) to optimize the fluid turning efficiency. A shape memory alloy thermal compensation ring (thickness 0.2-0.5mm) is set between it and the first honeycomb rectifier grid 701 to adapt to the thermal expansion difference at high temperature and prevent structural deformation or blockage. The embedding depth does not exceed 1 / 3 (about 8-12mm) of the total length of the edge flow channel 5112 to ensure uniform fluid distribution and not interfere with the movement of the sealing components. The dual system can reduce the local resistance coefficient in the turbulent area to 0.4 (0.7 for a single grid) through flow channel reconstruction, and reduce the total pressure drop of the system by 13%. The spiral guide layer of the first honeycomb rectifier grid 701 suppresses thermal eddies, and the pressure fluctuation is <±0.5MPa under the 205℃ operating condition. The shape memory alloy ring of the second honeycomb rectifier grid 702 maintains a flow equalization efficiency of 94% in deep-sea high-temperature wells.

[0167] Specifically, the outer walls of the central sealing ball 522, the edge sealing ball 532, and the reverse pushing ball 542 are all covered with double-layer sealing sleeves:

[0168] The inner layer is a 1.5-2mm hydrogenated nitrile rubber layer 801;

[0169] The outer layer is a 0.5-1mm compressible expandable graphite layer 802.

[0170] The hydrogenated nitrile butadiene rubber layer 801 serves as the first line of defense, providing essential elasticity to effectively absorb and mitigate mechanical stress caused by temperature changes and pressure fluctuations. It prevents wear caused by direct contact with hard sealing surfaces. Its excellent elasticity and resilience allow the sealing sleeve to adapt to sealing surfaces of different shapes and sizes, ensuring a tight fit and reducing the risk of leakage. The expanded graphite layer 802 possesses excellent high-temperature resistance, maintaining structural stability even under extreme temperature conditions without softening or decomposition. It is suitable for sealing requirements in high-temperature environments. When the temperature rises, the expanded graphite slightly expands (expansion rate ≤15%), automatically filling tiny gaps or imperfections between sealing surfaces, enhancing the sealing effect. Even in low-temperature environments, it maintains sufficient sealing capacity. Expanded graphite is suitable for most... The chemical substances exhibit good inertness, providing reliable sealing protection in corrosive environments and extending equipment lifespan. By combining hydrogenated nitrile rubber with expanded graphite, a bottom layer with good elasticity and adaptability, and a top layer with excellent temperature and corrosion resistance, are formed. This combination not only improves overall sealing performance but also increases system reliability and durability. Even if one layer ages or is damaged due to prolonged use or other reasons, the other layer can still maintain a certain sealing effect, reducing the risk of single-point failure and enhancing the safety factor of the entire sealing system. In deep well cementing operations, in high-pressure (≤105MPa), high-temperature (≤150℃) and corrosive media environments, the double-layer sealing sleeve can effectively prevent fluid leakage and ensure operational safety.

[0171] Working principle: This device is a special tool for deep well cementing operations. Through multi-stage sealing and fluid control design, it achieves the following core functions:

[0172] Unidirectional grouting: allows cement grout to flow unidirectionally from top to bottom, filling the wellbore annulus;

[0173] Anti-backflow locking: Automatically seals after grouting to prevent fluid backflow;

[0174] High-pressure seal: withstands high pressure and high temperature environments downhole;

[0175] Adaptive adjustment: It responds to downhole pressure fluctuations through a mechanical linkage structure;

[0176] Wear-resistant and erosion-resistant: Key components are protected by tungsten carbide / silicon carbide composite material to extend service life.

[0177] The specific workflow of this device is as follows:

[0178] Phase 1: Initial Shutdown (Equipment Downhole and Stationary)

[0179] Core status: All distribution channels are forcibly closed.

[0180] Mechanism of action:

[0181] Main spring preload mechanism

[0182] Central sealing assembly 52:

[0183] The first main spring 524 applies preload through the central fixed base 5231 of the central telescopic plate 523, pushing the central ball rod 521 to drive the central sealing ball 522 to tightly adhere to the first spherical sealing groove 601 (embedded with the first silicon carbide sealing ring 602, forming a metal-silicon carbide-metal triple seal. Silicon carbide has the characteristics of high temperature resistance (≤300℃) and wear resistance (friction coefficient ≤0.01), and can withstand the long-term effects of complex downhole environments). At this time, the central sealing ball 522 and the first spherical sealing groove 601 form a line seal (contact width 0.25mm), and the sealing pressure is directly transmitted by the preload of the first main spring 524.

[0184] Edge sealing assembly 53:

[0185] The second main spring 534 applies preload through the edge fixing base 5331 of the edge telescopic plate 533, pushing the edge ball rod 531 to drive the edge sealing ball 532 to tightly adhere to the second spherical sealing groove 603 (with the second silicon carbide sealing ring 604 embedded). The edge sealing ball 532 and the second spherical sealing groove 603 form a circumferentially distributed multi-point seal to ensure that there is no leakage path in the edge area.

[0186] Secondary spring auxiliary mechanism

[0187] Central telescopic plate 523:

[0188] When the secondary spring 5234 is in a compressed state, it transmits force upward through the sliding cavity 5233 of the lifting movable sleeve 5232, which helps the central sealing ball 522 maintain a seal even when the pre-compression of the first main spring 524 fails (such as due to local wear).

[0189] Edge expansion joint 533:

[0190] The auxiliary spring 5234 is connected to the conical surface of the bottom sealing plate 512 through the edge fixing base 5331 of the straight cylinder structure to form a continuous flow guide surface. At the same time, it compensates for the small displacement of the sealing ball 532 through elastic force, so that the auxiliary edge sealing ball 532 can still maintain the seal when the pre-compression of the second main spring 534 fails (such as local wear).

[0191] Reverse sealing lock

[0192] Reverse sealing assembly 54:

[0193] Nested active lever 545:

[0194] The concave area 546 is located 10mm above the bottom flow channel 5121 and does not overlap with the channel, ensuring that the reverse ball push 542 is in a completely closed state.

[0195] Return spring 549:

[0196] The fixed plate 548 presses the nested movable rod 545 to the bottom limit position of the lifting cavity 5451, and the reverse push ball 542 is pressed tightly against the third spherical sealing groove 605 (with the third silicon carbide sealing ring 606 embedded) by the spring force, forming a metal-silicon carbide-metal triple seal.

[0197] Double sealing sleeve:

[0198] The hydrogenated nitrile rubber layer 801 (1.5-2 mm) and the compressible expandable graphite layer 802 (0.5-1 mm) covering the outer wall of the reverse push ball 542 provide elastic cushioning in a static state, avoiding initial wear caused by direct contact between the hard sealing surfaces.

[0199] Phase 2: Cement grout injection (dynamic start-up process)

[0200] Core status: Three channels are activated in stages.

[0201] Mechanism of action:

[0202] Pressure breaking stage (critical pressure > 4 MPa)

[0203] Central passageway open:

[0204] The cement slurry pressure overcomes the preload of the first main spring 524 (the design value of this application is 3.5MPa), and the central sealing ball 522 moves down along the central ball rod 521, separating from the first spherical sealing groove 601 to form an annular flow gap (diameter 0.5-1.2mm).

[0205] Central telescopic plate 523:

[0206] The lifting sleeve 5232 moves downward under the pressure of cement slurry, isolating the first main spring 524 from contact with the slurry and preventing corrosion of the first main spring 524. The double straight gradually expanding conical guide section 5235 guides the fluid to the inlet of the bottom flow channel 5121, reducing local resistance loss by 37%.

[0207] Edge channel enabled:

[0208] The second main spring 534 is overcome by the cement slurry pressure, and the edge sealing ball 532 moves down along the edge ball rod 531 and separates from the second spherical sealing groove 603, forming a circumferentially distributed flow gap (in this application, it is set to 5 groups, with a flow gap spacing of 72° between each group).

[0209] Edge expansion joint 533:

[0210] The edge fixing base 5331 of the straight cylindrical structure is flush with the conical surface of the bottom sealing plate 512 to form a continuous flow guide surface and avoid fluid turbulence separation.

[0211] Linked to open the bottom channel

[0212] Linkage drive:

[0213] The downward movement of the central cue 521 and the edge cue 531 transmits power to the reverse sealing assembly 54 through the connecting rod 541. The fixed cue 543 pushes the nested movable rod 545 downward, and the concave area 546 precisely aligns with the bottom flow channel 5121 to form a trapezoidal flow section (maximum opening width 2.5mm).

[0214] Fluid optimization control:

[0215] First honeycomb grille 701 (embedded in the central circulation channel 5111 inlet section):

[0216] By using a layered, nested honeycomb rectifier layer and a spiral guide layer, the central fluid is rectified into laminar flow, reducing energy loss.

[0217] Second honeycomb grid 702 (embedded in the edge flow channel 5112 inlet):

[0218] A shape memory alloy thermal compensation ring is used to offset thermal expansion and contraction caused by temperature changes, thereby eliminating flow separation in the conical region.

[0219] Phase 3: Grouting completed (intelligent reset seal)

[0220] Core status: Triple seal, closed in stages

[0221] Mechanism of action:

[0222] Main spring controls reset

[0223] Central sealing assembly 52:

[0224] When the pump pressure drops to <2MPa, the first main spring 524 releases the preload, pushing the central sealing ball 522 upward to reset, and the sealing contact pressure rises to 5MPa within 0.5s.

[0225] Double sealing sleeve 801 / 802:

[0226] The expanded graphite layer 802 undergoes micro-expansion (expansion rate ≤15%) during the repositioning process of the sealing ball, filling microscopic defects and forming a plastic seal.

[0227] Edge sealing assembly 53:

[0228] The second main spring 534 synchronously pushes the edge sealing ball 532 to press the second spherical sealing groove 603, with a reset time of <1.2s (avoiding the backflow time window).

[0229] Reverse channel double interlocking

[0230] Linkage:

[0231] The upward movement of the connecting rod 541 causes the nested movable rod 545 to move upward, and the concave area 546 disengages from the bottom flow channel 5121.

[0232] Return spring 549:

[0233] Pushing the reverse push ball 542 to press the third silicon carbide sealing ring 606, forming a metal-silicon carbide-metal triple seal.

[0234] Sealing topology optimization

[0235] Spherical-sealing ring contact:

[0236] The contact width between the central sealing ball 522 and the first spherical sealing groove 601 is 0.25 mm, and the contact width between the edge sealing ball 532 and the second spherical sealing groove 603 is 0.15 mm.

[0237] Thermal expansion compensation:

[0238] The shape memory alloy thermal compensation ring 539 expands by 0.15 mm at 150℃, eliminating sealing failure caused by thermal stress.

[0239] Phase 4: Bottom-of-well back pressure (overpressure synergistic seal enhancement)

[0240] Core status: The sealing strength of the entire system has been doubled.

[0241] Mechanism of action:

[0242] Reverse push ball mechanical trigger

[0243] Back pressure threshold:

[0244] When the back pressure is greater than 5 MPa, the movable plate 544 overcomes the preload of the return spring 549 and moves upward.

[0245] Fitting and limiting the fit:

[0246] When the movable plate 544 is displaced to its limit, it pushes the ball 542, the movable plate 544, and the fitting limit plate 547 in the opposite direction to fit together, forming a continuous spherical seal.

[0247] Movable cavity 5421:

[0248] The bottom movable cavity 5421 of the reverse push ball 542 allows for micro-permeation of fluid (flow rate < 0.5 L / min), avoiding stress concentration in the seal.

[0249] Mechanical linkage supercharging

[0250] Central seal reinforcement:

[0251] The connecting rod 541 moves upward and applies a lifting force through the fixed ball 543, while the central sealing ball 522 applies additional clamping force to ensure the sealing stability of the central flow channel 5111.

[0252] Edge sealing enhancement:

[0253] The edge sealing ball 532 applies additional clamping force to ensure the sealing stability of the edge flow channel 5112.

[0254] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0255] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A floating hoop and float shoe for deep well cementing, characterized in that: include: The floating hoop (1), sleeve (2), floating shoe (3) and guide cap (4) are connected in sequence by thread. The float hoop (1) is provided with a first one-way feeding unit (5), and the float shoe (3) is provided with a second one-way feeding unit (6) with the same structure as the first one-way feeding unit (5). The first unidirectional feeding unit (5) includes: The fixed skirt structure (51) has a top sealing plate (511) with a gradually expanding cone shape and a bottom sealing plate (512) with a gradually contracting cone shape. The two are coaxially fixed in the floating hoop (1). Central sealing assembly (52): a central ball rod (521) that passes through the bottom sealing plate (512), with a central sealing ball (522) fixed at its top and corresponding to the central flow channel (5111) of the top sealing plate (511). The central ball rod (521) is fitted with a central telescopic plate (523), and a central jacket layer that accommodates the first main spring (524) is formed between the two. Edge sealing assembly (53): a plurality of edge rods (531) surrounding the central rod (521), with an edge sealing ball (532) fixed at the top and corresponding to the edge flow channel (5112) of the top sealing plate (511). An edge telescopic plate (533) is fitted over the edge rods (531), and an edge jacket layer for accommodating the second main spring (534) is formed between the two. Reverse sealing assembly (54): The top of the reverse cue assembly is connected to the central telescopic plate (523) and the edge telescopic plate (533) through the connecting rod (541), and the bottom passes through the bottom flow channel (5121) of the bottom sealing plate (512) and fixes the reverse push ball (542).

2. The floating hoop and float shoe for deep well cementing according to claim 1, characterized in that: The reverse cue assembly includes: The fixed cue stick (543) is fixed to the top of the connecting rod (541) and the movable plate (544) is fixed to the bottom. The nested movable rod (545) is movably sleeved outside the fixed rod (543), with the bottom fixed to the reverse push ball (542), and its outer wall forms an indented area (546) with a diameter smaller than the bottom flow channel (5121).

3. The floating hoop and float shoe for deep well cementing according to claim 2, characterized in that: The bottom of the reverse ball pusher (542) has a movable cavity (5421), and the bottom of the movable cavity (5421) is provided with a circumferentially distributed fitting limiting plate (547). The bottom of the movable plate (544) is provided with a matching limiting groove (5441) corresponding to the matching limiting plate (547). The nested movable rod (545) is provided with a lifting cavity (5451), and a fixed plate (548) is fixedly sleeved on the fixed ball rod (543). A return spring (549) is provided between the fixed plate (548) and the top of the lifting cavity (5451). When the movable plate (544) descends to the bottom of the movable cavity (5421), a compensation gap is formed between the two. When the back pressure in the well exceeds the threshold, the movable plate (544) moves upward so that the fitting limiting groove (5441) fits into the fitting limiting plate (547) to form a continuous sealing surface.

4. The floating hoop and float shoe for deep well cementing according to claim 1, characterized in that: The central telescopic plate (523) and the edge telescopic plate (533) have the same structure and similar functions. The central telescopic plate (523) includes: A central fixing base (5231) is fixed to the bottom sealing plate (512); The lifting movable sleeve (5232) is sleeved outside the central cue (521), and the inner wall of the sleeve is provided with a lifting slide cavity (5233). The top of the central fixed base (5231) extends into the lifting slide cavity (5233) and is fixedly installed with a lifting slide plate (5236). The auxiliary spring (5234) located in the lifting slide cavity (5233) abuts against the lifting movable sleeve (5232) and the central fixed base (5231) at both ends respectively.

5. A floating hoop and float shoe for deep well cementing according to claim 4, characterized in that: The central fixed base (5231) of the central telescopic plate (523) extends to form a double straight gradually expanding conical surface guide section (5235), which extends to the inlet of the bottom flow channel (5121) to guide the cement slurry to flow into the flow channel. The edge fixing base (5331) of the edge telescopic plate (533) is a straight cylindrical structure, and its outer wall is flush with the conical surface of the bottom sealing plate (512) to form a continuous flow guide surface.

6. A floating hoop and float shoe for deep well cementing according to claim 1, characterized in that: The edges of the central flow channel (5111), the edge flow channel (5112), and the bottom flow channel (5121) are all polished with a radius of R0.5-R1mm. The inner walls of the central flow channel (5111), the edge flow channel (5112) and the bottom flow channel (5121) are all covered with a 200-300μm tungsten carbide wear-resistant layer; The outer surfaces of the top sealing plate (511) and the bottom sealing plate (512) are both covered with a 150-200μm tungsten carbide wear-resistant layer.

7. A floating hoop and float shoe for deep well cementing according to claim 1, characterized in that: The central flow channel (5111) is provided with a first spherical sealing groove (601) at the end that contacts the central sealing ball (522), and the edge of the first spherical sealing groove (601) is inlaid with a first silicon carbide sealing ring (602). The edge flow channel (5112) is provided with a second spherical sealing groove (603) at the end that contacts the edge sealing ball (532), and the edge of the second spherical sealing groove (603) is inlaid with a second silicon carbide sealing ring (604). The bottom flow channel (5121) is provided with a third spherical sealing groove (605) at the end that contacts the reverse push ball (542), and a third silicon carbide sealing ring (606) is inlaid on the edge of the third spherical sealing groove (605).

8. A floating hoop and float shoe for deep well cementing according to claim 1, characterized in that: The central flow channel (5111) is located in the central plane area of ​​the top sealing plate (511); The edge flow channel (5112) is located in the conical area of ​​the top sealing plate (511) and is evenly distributed along the circumference of the conical surface; The bottom flow channel (5121) is located in the transition area between the conical surface and the plane of the bottom sealing plate (512), and is ≤10mm from the plane boundary; A first honeycomb-shaped rectifier grille (701) is provided above the planar area of ​​the top sealing plate (511); A second honeycomb rectifier grille (702) is provided in the conical area of ​​the top sealing plate (511).

9. A floating hoop and float shoe for deep well cementing according to claim 8, characterized in that: The first honeycomb rectifier grille (701) is embedded in the inlet section of the central flow channel (5111) in a layered nesting manner, and includes a honeycomb rectifier layer and a spiral guide layer from top to bottom; The second honeycomb rectifier grille (702) is embedded into the inlet of the edge flow channel (5112) through a conical bonding structure, and a shape memory alloy heat compensation ring is provided between the two. The embedding depth of both the first honeycomb rectifier grille (701) and the second honeycomb rectifier grille (702) does not exceed 1 / 3 of the total length of the corresponding channel.

10. A floating hoop and float shoe for deep well cementing according to claim 1, characterized in that: The outer walls of the central sealing ball (522), the edge sealing ball (532), and the reverse push ball (542) are all covered with double-layer sealing sleeves: The inner layer is a 1.5-2mm hydrogenated nitrile rubber layer (801). The outer layer is a 0.5-1mm compressible expandable graphite layer (802).

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