Spring type float collar float shoe for well cementation

Abstract

The utility model relates to the technical field of well cementation, in particular to a spring type float collar float shoe for well cementation. Comprising a float collar, a baffle ring is fixed in the float collar, a top ring is detachably and fixedly connected in the float collar below the baffle ring, a middle ring is hermetically mounted in the float collar between the top ring and the baffle ring, a fixing sleeve is concentrically fixed at the upper end of the middle ring, a sliding ring is slidably and hermetically connected in the vertical direction of an inner hole of the middle ring, and an outer ring is arranged in a ring cavity between the fixing sleeve and the sliding ring. A spring is arranged between the outer ring and the middle ring, a sealing column is inserted into the upper end of the sliding ring in a sliding and sealing mode, the upper end of the sealing column is fixedly connected with the upper end of the fixing sleeve, and the lower end of the float collar is connected with a float shoe. According to the utility model, the problems of easy corrosion, large cement resistance, complex installation and the like of the spring in the prior art are systematically solved through the sealing cavity for packaging the spring, the straight-through flow channel design, the modular assembly structure and the multi-stage redundant sealing.

Description

TECHNICAL FIELD

[0001] The utility model relates to a well cementing technical field, concretely relates to a spring type float collar float shoe for well cementing. BACKGROUND

[0002] The float collar float shoe is a kind of casing guide shoe or coupling capable of generating buoyancy, due to the high temperature resistance, good sealing and drillability of float shoe or float collar, convenient connection, thus can replace guide shoe, casing shoe etc., float shoe or float collar can be used not only for general technical casing and reservoir casing, but also for deep well, ultra-deep well and special process well.

[0003] The patent file with publication number CN220118093U discloses a spring type float collar float shoe for well cementing, which comprises a spring type float collar float shoe body and a base layer, the bottom of the spring type float collar float shoe body is fixedly connected with a liquid outlet head in communication, the inner wall of the spring type float collar float shoe body is fixedly connected with a stop block, the inner wall of the spring type float collar float shoe body is fixedly connected with a bottom shell, the inner wall of the bottom shell is fixedly connected with a connecting rod, the surface of the connecting rod is sleeved with a spiral spring, the top of the connecting rod is connected with a limiting seat, one end of the spiral spring is in close contact with the inner wall of the limiting seat, the other end of the spiral spring is in close contact with the inner wall of the bottom shell, and one end of the connecting rod is provided with a sealing mechanism. The assembly for controlling the one-way flow of cement of the spring type float collar float shoe is complex to install, and at the same time, the bottom shell for guiding the connecting rod needs to be arranged, the cement needs to flow through the through hole on the bottom shell and then be discharged through the liquid outlet head, which increases the resistance of cement discharge. In the technical scheme, the spring is exposed, the spring is easy to be contaminated and corroded, which affects the performance of the spring, and also reduces the service life of the spring.

[0004] To solve the problem of spring exposure, the patent file with publication number CN222253870U discloses a float collar float shoe for well cementing, mud enters the float collar float shoe body, the pressure of the mud pushes the sealing plate and the top protective shell, then the moving sealing plate extrudes the spring located in the top protective shell through the top protective shell, so that the top protective shell moves back to the inside of the moving groove in the bottom protective shell, and at the same time, the spring on the outside of the connecting rod moves back downward, then the mud flows to the through hole through the outside of the top protective shell and the bottom protective shell, and then the mud is discharged from the liquid outlet head into the well wall through the through hole, in this process, the top protective shell and the bottom protective shell protect the spring, so as to avoid the pollution and corrosion of the spring, thereby ensuring the performance of the spring and increasing the service life of the spring. In the technical scheme, the assembly for preventing cement from flowing backward is complex to install, and there is also the problem of large cement discharge resistance. SUMMARY

[0005] The utility model discloses a main purpose lies in providing a kind of cementing spring type float collar float shoe that can reduce cement discharge resistance, easy to install, can improve the efficiency of assembly.

[0006] In order to achieve the above object, the utility model provides technical scheme is:

[0007] A kind of cementing spring type float collar float shoe, including float collar, retaining ring is fixed in float collar, detachable fixed connection is established in the float collar below the retaining ring, top ring is sealed and installed in the float collar between retaining ring and top ring, fixed sleeve is fixed concentrically in the upper end of intermediate ring, sliding seal connection is established in the vertical direction of intermediate ring inner hole, outer ring is arranged in the ring cavity between fixed sleeve and sliding ring, outer ring is detachably fixed connection with sliding ring, outer ring and fixed sleeve inside sliding seal connection, spring is arranged between outer ring and intermediate ring, sliding seal plug-in has sealing column in the upper end of sliding ring, the upper end of sealing column is fixedly connected with the upper end of fixed sleeve by connecting rod, float shoe is connected in the lower end of float collar, float collar is connected with float shoe by screw thread, multiple outlet holes are set up on float shoe.

[0008] Specifically, the top ring is connected with the float collar by screw thread.

[0009] Specifically, the outer ring is connected with the sliding ring by screw thread.

[0010] Specifically, the lower end of the sealing column is provided with a guide cone surface.

[0011] Specifically, the intermediate ring is connected with the float collar by a sealing ring, the sliding ring is connected with the intermediate ring by a sealing ring, and the sealing column is connected with the sliding ring by a sealing ring.

[0012] Compared with the prior art, the utility model has the beneficial effects that:

[0013] 1. By encapsulating the spring in the sealed cavity formed by the fixed sleeve, the intermediate ring and the sliding ring, the spring is prevented from being directly exposed to the cement flow channel, the structure of the guide bottom shell or the protective shell in the prior art is cancelled, and the blocking components through which the cement flows are reduced. The cement directly passes through the straight-through flow channel formed by the inner cavity of the sliding ring and the sealing column to discharge, the flow channel has a large cross-sectional area and a short path, significantly reduces the flow resistance, and improves the cementing efficiency.

[0014] 2. The spring is completely isolated in the sealed cavity, so that the cement, mud or corrosive medium does not contact the spring.

[0015] 3. The intermediate ring, the sliding ring, the outer ring, the sealing column and the spring are preassembled as a whole module, and the threaded connection of the top ring and the float collar realizes quick installation and disassembly without complex positioning or additional guide structure. The threaded connection of the outer ring and the sliding ring allows independent replacement of the spring assembly, reducing maintenance costs.

[0016] 4, the intermediate ring is sealed and connected with the float collar, the slip ring is sealed and connected with the intermediate ring, and the sealing column is sealed and connected with the slip ring. A multi-stage sealing ring design forms a multi-layer redundant seal, effectively preventing high-pressure cement back seepage. The spring rebound force of the plug-in cooperation of the sealing column and the slip ring realizes rapid closure. The guide cone surface of the sealing column ensures accurate reset under reverse pressure, and the leakage prevention reliability is high.

[0017] 5, the guide cone surface at the lower end of the sealing column guides the centering of the slip ring and the sealing column when the spring rebounds, reduces the risk of eccentric wear, and prolongs the service life of the sealing assembly. BRIEF DESCRIPTION OF DRAWINGS

[0018] Fig. 1 is a sectional view of the float collar of the float shoe.

[0019] Fig. 2 is a top view of the cooperation of the sealing column, the slip ring and the intermediate ring.

[0020] The names of the parts in the drawings are: 1, float collar, 2, float shoe, 3, hole, 4, top ring, 5, retaining ring, 6, intermediate ring, 7, slip ring, 8, fixed sleeve, 9, outer ring, 10, spring, 11, sealing column, 12, connecting rod. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0022] Embodiment one: refer to Figs. 1-2 As shown in the figure, a spring type float collar float shoe for well cementing includes a float collar 1, a retaining ring 5 is fixed in the float collar 1, a top ring 4 is detachably fixed and connected in the float collar 1 below the retaining ring 5. Specifically, the top ring 4 is threadedly connected with the float collar 1.

[0023] An intermediate ring 6 is sealingly installed in the float collar 1 between the top ring 4 and the retaining ring 5, the intermediate ring 6 is sealingly connected with the float collar 1 through a sealing ring, a fixed sleeve 8 is concentrically fixed on the upper end of the intermediate ring 6, a slip ring 7 is slidingly and sealingly connected in the vertical direction of the inner hole of the intermediate ring 6, the slip ring 7 is sealingly connected with the intermediate ring 6 through a sealing ring, an outer ring 9 is arranged in the ring cavity between the fixed sleeve 8 and the slip ring 7, and the outer ring 9 is detachably fixedly connected with the slip ring 7. Specifically, the outer ring 9 is threadedly connected with the slip ring 7. A spring 10 is arranged between the outer ring 9 and the intermediate ring 6.

[0024] A sealing column 11 is slidingly and sealingly inserted into the upper end of the slip ring 7, the sealing column 11 is sealingly connected with the slip ring 7 through a sealing ring, a guide cone surface is formed at the lower end of the sealing column 11, and the upper end of the sealing column 11 is fixedly connected with the upper end of the fixed sleeve 8 through a connecting rod 12.

[0025] The lower end of the float hoop 1 is connected to the float shoe 2. The float hoop 1 and the float shoe 2 are threaded together. The float shoe 2 has multiple outlet holes 3.

[0026] During assembly, the intermediate ring 6, slip ring 7, fixed sleeve 8, outer ring 9, sealing column 11 and connecting rod 12 are integrated as a whole. The intermediate ring 6 is placed in the floating hoop 1 below the top ring 4, and then the top ring 4 is threaded into the floating hoop 1. After the top ring 4 and the retaining ring 5 clamp the intermediate ring 6, the assembly is completed.

[0027] The intermediate ring 6, slip ring 7, outer ring 9, sealing post 11, and spring 10 are pre-assembled as a single module. Quick installation and disassembly are achieved through the threaded connection between the top ring 4 and the floating hoop 1, eliminating the need for complex positioning or additional guiding structures. The threaded connection between the outer ring 9 and the slip ring allows for independent replacement of the spring 10 assembly, reducing maintenance costs.

[0028] During operation, float hoop 1 and float shoe 2 are connected to the casing string. Float shoe 2 can guide the casing string as it descends.

[0029] During cementing, the cement inside the casing string pushes the slip ring 7 downward, compressing the spring 10. When the sealing column 11 separates from the slip ring 7, the cement is discharged downward through the inner cavity of the slip ring 7. The cement enters the float shoe 2 and is discharged through the outlet hole 3.

[0030] When the cement pressure in the casing above the float hoop 1 decreases, the slip ring 7 moves upward under the elastic force of the spring 10 and re-seals the sealing column 11, thus preventing cement backflow.

[0031] Example 2: Based on Example 1, referring to... Figs. 1-2 As shown, the outer ring 9 is connected to the inner sliding seal of the fixed sleeve 8.

[0032] Since the outer ring 9 is slidably sealed to the fixed sleeve 8, a sealed cavity is formed between the fixed sleeve 8, the intermediate ring 6 and the slip ring 7, which can effectively isolate cement and prevent cement from contacting the spring 10. The spring 10 is located in the sealed cavity, which can effectively prevent moisture from entering the spring 10.

[0033] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A spring-type float collar float shoe for cementing well, comprising a float collar (1), characterized in that, The floating collar (1) is fixed with a blocking ring (5), and a top ring (4) is detachably fixed and connected below the floating collar (1). The floating collar (1) between the top ring (4) and the blocking ring (5) is sealingly installed with an intermediate ring (6), and the upper end of the intermediate ring (6) is concentrically fixed with a fixed sleeve (8). The vertical direction of the inner hole of the intermediate ring (6) is slidingly and sealingly connected with a sliding ring (7). The ring cavity between the fixed sleeve (8) and the sliding ring (7) is provided with an outer ring (9), and the outer ring (9) is detachably fixed and connected with the sliding ring (7). The outer ring (9) is slidingly and sealingly connected with the inside of the fixed sleeve (8). The outer ring (9) and the intermediate ring (6) are provided with a spring (10). The upper end of the sliding ring (7) is slidingly and sealingly inserted with a sealing column (11). The upper end of the sealing column (11) is fixedly connected with the upper end of the fixed sleeve (8) through a connecting rod (12). The lower end of the floating collar (1) is connected with a float shoe (2), and a plurality of outlet holes (3) are formed in the float shoe (2).

2. The spring-type float collar float shoe of claim 1, wherein, The top ring (4) is threadedly connected with the floating collar (1).

3. The spring-type float collar float shoe of claim 1, wherein, The outer ring (9) is threadedly connected with the sliding ring (7).

4. The spring-type float collar float shoe of claim 1, wherein, The lower end of the sealing column (11) is provided with a guide conical surface.

5. The spring-type float collar float shoe of claim 1, wherein, The intermediate ring (6) is sealingly connected with the floating collar (1) through a sealing ring. The sliding ring (7) is sealingly connected with the intermediate ring (6) through a sealing ring. The sealing column (11) is sealingly connected with the sliding ring (7) through a sealing ring.

6. The spring-type float collar float shoe of claim 1, wherein, The floating collar (1) is threadedly connected with the float shoe (2).

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