Float collar and well cementation casing system

Abstract

The utility model discloses a float collar and a well cementation casing system. The float collar comprises a shell, an inner plug bush and a check valve core, wherein the inner plug bush and the check valve core are arranged in the shell; the check valve element is arranged below the inner inserting sleeve, and oil well cement is filled between the inner wall of the shell and the outer wall of the inner inserting sleeve and between the inner wall of the shell and the check valve element. The inner plug bush comprises a first hole section and a second hole section, and the aperture of the first hole section is larger than that of the second hole section; the first hole section is used for being matched with an inner pipe cementing plug, the second hole section is used for being matched with a drill rod rubber plug, and the second hole section is provided with a clamping spring groove so as to be matched with a clamping spring of the drill rod rubber plug to limit the drill rod rubber plug. The problems of easy plug reserving, empty replacement and the like of inner pipe method well cementation can be solved, and the well cementation construction risk is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of oilfield drilling inner tube cementing, in particular to a floating collar and cementing casing system. Background Art

[0002] The float collar is an important downhole tool for cementing construction. It has the function of forward flow and reverse cutoff, that is, the cement slurry flows forward and is injected into the annulus, while preventing the cement slurry in the annulus from flowing back into the pipe. After the rubber plug runs to the float collar position, the float collar needs to withstand the pressure of the forward impact pressure.

[0003] In surface cementing, the inner tube cementing process is often used to improve cementing construction efficiency and effectively control the amount of cement slurry used. The core tool of this process is the inner plug float collar. The specific construction process of surface cementing is as follows: insert the inner plug float collar at the bottom of the casing string, insert the drill bit into the casing, connect the plug that matches the inner plug float collar at the bottom of the drill bit, insert the plug into the float collar to form a seal, press the drill bit down with a 3-5t hanging weight, and then the cementing and cement slurry injection operation can be carried out. When the cement slurry returns from the annulus of the surface casing, use clean water to quantitatively replace the cement slurry in the drill bit. After the displacement reaches the designed amount, the drill is directly pulled out. Utility Model Content

[0004] The inventors of the present application have discovered that as the depth of surface cementing increases, the length of the drill bit increases, and the volume inside the pipe increases, inaccurate quantitative replacement of clean water may easily cause excessive cement slurry to remain in the pipe or cause emptying accidents, which in turn may affect the cementing effect of the surface cementing.

[0005] In view of the above problems, the present utility model is proposed to provide a floating collar and cementing casing system that overcomes the above problems or at least partially solves the above problems.

[0006] The utility model provides a floating collar, comprising: a shell, an inner sleeve and a check valve core arranged in the shell;

[0007] The check valve core is arranged below the inner sleeve, and the space between the inner wall of the housing and the outer wall of the inner sleeve, and between the inner wall of the housing and the check valve core is filled with oil well cement;

[0008] The inner sleeve comprises a first hole section and a second hole section, and the aperture of the first hole section is larger than the aperture of the second hole section;

[0009] The first hole section is used to cooperate with the inner pipe cementing plug, and the second hole section is used to cooperate with the drill pipe plug. The second hole section is provided with a retaining ring groove to cooperate with the retaining ring of the drill pipe plug to limit the drill pipe plug.

[0010] In an optional embodiment, the floating collar provided by the embodiment of the utility model further includes: a sealing baffle;

[0011] The sealing partition is arranged between the housing and the check valve core, and a sealing ring is arranged between the sealing partition and the housing, and between the sealing partition and the check valve core.

[0012] In an optional embodiment, the floating collar provided by the embodiment of the utility model further includes: a sealing baffle;

[0013] The sealing partition is arranged between the housing and the check valve core, and a sealing ring is arranged between the sealing partition and the housing, and between the sealing partition and the check valve core.

[0014] In an optional embodiment, the thickness of the sealing partition is 15mm-25mm.

[0015] In an optional embodiment, the first hole segment includes a tapered hole segment and a cylindrical segment;

[0016] One end of the cylindrical section is connected to the end of the tapered hole section with a smaller diameter, and the other end is connected to the second hole section. One or more of threads, patterns or grooves are arranged on the outer surface of the cylindrical section.

[0017] In an optional embodiment, when a thread is provided on the outer surface of the cylindrical segment, the thread is a right-handed trapezoidal thread, and the pitch of the thread is 5-10 mm, and the diameter is 100-110 mm.

[0018] In an optional embodiment, a boss is provided on the outer wall of the second hole section, a plurality of through holes are provided on the boss, and the through holes are filled with oil well cement.

[0019] In an optional embodiment, the floating collar provided by the embodiment of the utility model further includes: a drill pipe rubber plug;

[0020] The drill pipe rubber plug comprises: a frame, a leather cup sleeved on the upper part of the frame, and a sealing ring installation groove and a retaining spring arranged at the lower part of the frame;

[0021] The skeleton is used to cooperate with the second hole section to press and seal the second hole section.

[0022] In an optional embodiment, the inner sleeve is an inner aluminum sleeve.

[0023] Based on the same inventive concept, the embodiment of the utility model also provides a cementing casing system, including: a casing, a drilling tool, an inner pipe cementing plug and the above-mentioned floating collar;

[0024] The lower end of the casing is connected to the upper end of the shell of the floating collar;

[0025] The inner tube cementing plug and the drill tool are arranged in the casing, and the upper end of the inner tube cementing plug is connected to the lower end of the drill tool, and the lower end is plugged into the first hole section of the floating collar.

[0026] In an optional embodiment, the cementing casing system provided by the embodiment of the utility model further includes: a control unit;

[0027] The control unit is used to monitor whether the cement slurry in the casing and the wellbore annulus meets the preset requirements, and control the drill pipe rubber plug to be put into the drilling tool after the cement slurry meets the preset requirements; the preset requirement is: cement slurry returns from the casing and the wellbore annulus.

[0028] The beneficial effects of the above technical solution provided by the embodiment of the utility model at least include:

[0029] The floating collar provided by the embodiment of the utility model has an inner sleeve which is provided with a first hole section for cooperating with the inner pipe cementing plug and a second hole section for cooperating with the drill pipe plug, and a retaining spring groove is provided in the second hole section for cooperating with the spring of the drill pipe plug to limit the drill pipe plug; in the process of using clean water to replace the cement slurry in the drill tool during surface cementing, the drill pipe plug can be put into the drill tool, and the clean water can be used to replace the drill pipe plug to the position of the floating collar for collision and pressure, and the retaining spring of the drill pipe plug cooperates with the retaining spring groove of the floating collar to form a self-locking, at which time the process of replacing the cement slurry in the drill tool with the clean water is completed, compared with the existing method of quantitatively replacing the cement slurry with clean water, it can reduce the occurrence of excessive cement slurry in the pipe or empty cement slurry caused by inaccurate clean water metering; at the same time, the second hole section of the floating collar forms a self-locking with the drill pipe plug, which can further prevent the backflow of cement slurry.

[0030] Other features and advantages of the utility model will be described in the subsequent description, and partly become apparent from the description, or understood by practicing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings.

[0031] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0033] Figure 1It is a schematic diagram of the overall structure of the floating hoop in the embodiment of the utility model;

[0034] Figure 2 This is a schematic diagram of the structure of the inner sleeve of the embodiment of the utility model;

[0035] Figure 3 This is a schematic diagram of the structure of the rubber plug in the embodiment of the utility model;

[0036] Figure 4 This is a schematic diagram of the structure of the inner tube cementing plug in the embodiment of the utility model;

[0037] Figure 5 This is a schematic diagram of the inner pipe cementing plug in the embodiment of the utility model when it is inserted into the floating collar;

[0038] Figure 6 This is a schematic diagram of the drill pipe rubber plug in the embodiment of the utility model in the state of self-locking by collision pressure;

[0039] Figure 7 It is a schematic diagram of the floating collar flowing through the drill pipe after it is pulled out in the embodiment of the utility model.

[0040] Description of reference numerals:

[0041] 1. Shell; 2. Inner sleeve; 3. Check valve core; 4. Sealing diaphragm; 5. Oil well cement; 6. Drill pipe rubber plug; 7. Inner pipe cementing plug;

[0042] 21. First hole section; 22. Second hole section; 211. Tapered hole section; 212. Cylindrical section; 213. Thread; 221. Retaining ring groove; 222. Boss; 223. Through hole; 41. Sealing ring; 61. Frame; 62. Leather cup; 63. Retaining ring; 64. Sealing ring mounting groove. DETAILED DESCRIPTION

[0043] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0044] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] The inventors of the present application have discovered that as the depth of surface cementing increases, the length of the drill bit increases, and the volume inside the pipe increases, inaccurate quantitative water displacement measurement may easily cause excessive cement blockage or empty cement in the casing. In addition, in the event of excessive blockage, if abnormal conditions occur during the drilling process, such as the need to repair equipment, accidents of drilling bit welding in the pipe often occur, which in turn affects the cementing effect of the surface cementing.

[0047] In order to solve the problems existing in the prior art, the embodiment of the utility model provides a floating collar and cementing casing system to solve the problems of easy plugging, emptying and internal welding of drilling tools in the case of plugging during cementing of the inner tube, and avoid the risk of cementing construction. Among them, the inner wall described in this embodiment is the inner surface, and the outer wall is the outer surface.

[0048] The floating collar provided in the embodiment of the utility model refers to Figures 1 to 3 As shown, it comprises: a housing 1, an inner sleeve 2 and a check valve core 3 arranged in the housing 1;

[0049] The check valve core 3 is arranged below the inner sleeve 2, and the space between the inner wall of the housing 1 and the outer wall of the inner sleeve 2, and between the inner wall of the housing 1 and the check valve core 3 is filled with oil well cement 5;

[0050] The inner sleeve 2 includes a first hole section 21 and a second hole section 22, and the aperture of the first hole section 21 is larger than the aperture of the second hole section 22;

[0051] The first hole section 21 is used to cooperate with the inner pipe cementing plug 7, and the second hole section 22 is used to cooperate with the drill pipe plug 6. The second hole section 22 is provided with a retaining ring groove 221 to cooperate with the retaining ring 63 of the drill pipe plug 6 to limit the drill pipe plug 6.

[0052] The floating collar, in addition to being provided with a first hole section 21 for cooperating with the inner pipe cementing plug 7, is also provided with a second hole section 22 for cooperating with the drill pipe plug 6, and a retaining spring groove 221 is provided in the second hole section 22 for cooperating with the spring of the drill pipe plug 6 to limit the drill pipe plug 6; in the process of using clean water to replace the cement slurry in the drill tool in surface cementing, the drill pipe plug 6 can be put into the drill tool, and the drill pipe plug 6 can be replaced by clean water to the position of the floating collar for collision and pressure, and the retaining spring 63 of the drill pipe plug 6 and the retaining spring groove 221 of the floating collar can form a self-locking, at this time, the process of replacing the cement slurry in the drill tool with clean water is completed, compared with the existing method of using clean water to quantitatively replace cement slurry, it can reduce the occurrence of cement slurry in the pipe due to inaccurate clean water metering. The second hole section 22 of the floating collar forms a self-locking with the drill pipe plug 6, which can further prevent the backflow of cement slurry.

[0053] In one embodiment, referring to Figure 1 As shown, the floating collar of this embodiment may also include: a sealing baffle 4;

[0054] The sealing diaphragm 4 is disposed between the housing 1 and the check valve core 3 , and a sealing ring 41 is disposed between the sealing diaphragm 4 and the housing 1 , and between the sealing diaphragm 4 and the check valve core 3 .

[0055] Among them, the sealing baffle 4 can be specifically made of plastic material. The setting of the sealing baffle 4 can support and assist in sealing the oil well cement 5. When the oil well cement 5 cracks, the presence of the sealing baffle 4 can prevent the cement slurry injected into the well from flowing back along the cracks in the oil well cement 5.

[0056] The thickness of the sealing baffle 4 may be 15 mm to 25 mm. The specific thickness of the sealing baffle 4 is not specifically limited in the embodiment of the utility model and may be selected according to actual needs.

[0057] Further, see Figure 1 and Figure 2 As shown, the first hole section 21 of the inner sleeve 2 includes a tapered hole section 211 and a cylindrical section 212;

[0058] One end of the cylindrical section 212 is connected to the end of the tapered hole section 211 with a smaller diameter, and the other end is connected to the second hole section 22, and one or more of threads, patterns or grooves are arranged on the outer surface of the cylindrical section 212. The structural design of the tapered hole section 211 of the inner sleeve 2 can facilitate the introduction of the inner pipe cementing plug 7 when the floating collar is in use, wherein the structure of the inner pipe cementing plug 7 is referred to Figure 4 As shown, when in use, the sealing shaft at the lower end of the inner tube cementing plug 7 is provided with a sealing ring 41 which can cooperate with the inner hole of the cylindrical section 212 of the floating collar to form a seal.

[0059] In addition, threads, patterns or grooves may be provided on the outer surface of the cylindrical section 212 to help enhance the bonding strength between the inner sleeve 2 and the oil well cement 5 and prevent the inner sleeve 2 from rotating relative to the oil well cement 5 during subsequent drilling and removal, thereby preventing drilling and removal failure.

[0060] Further, see Figure 2 As shown, it is a schematic diagram of the structure in which a thread 213 is provided on the outer surface of the cylindrical section 212; and in the state in which the thread 213 is provided on the outer surface of the cylindrical section 212, the thread 213 can be a right-handed trapezoidal thread 213, and the pitch of the thread 213 can be 5-10mm, and the diameter is 100-110mm. That is, in order to better enhance the bonding strength between the inner sleeve 2 and the oil well cement 5, the provided thread 213 can be a coarse thread.

[0061] Reference Figure 2 As shown, a boss 222 is provided on the outer wall of the second hole section 22, and a through hole 223 is provided on the boss 222, and the through hole 223 is filled with oil well cement 5. The structure in which the boss 222 is provided on the outer wall of the second hole section 22 and the through hole 223 is provided on the boss 222 can further strengthen the bonding strength between the inner casing and the oil well cement 5 by filling the through hole 223 with oil well cement 5. Among them, the through holes 223 can be distributed along the circumferential direction of the boss 222, and the shape, size and number of the through holes 223 are not specifically limited in the embodiment of the utility model, and can be selected according to actual needs.

[0062] In one embodiment, the floating collar of the utility model may further include: a drill pipe rubber plug 6;

[0063] Reference Figure 3 As shown, the drill pipe rubber plug 6 comprises: a frame 61, a leather cup 62 sleeved on the upper part of the frame 61, and a sealing ring mounting groove 64 and a retaining spring 63 arranged at the lower part of the frame 61;

[0064] The skeleton 61 is used to cooperate with the second hole section 22 to press and seal the second hole section 22 .

[0065] Among them, the sealing ring installation groove 64 is used to install the sealing ring 41, so that after the drill pipe plug 6 runs to the matching position, the drill pipe plug 6 and the inner sleeve 2 form a seal and can be pressed. After the retaining spring 63 reaches the matching position, the tail of the retaining spring 63 bounces up and the tail is a straight shoulder surface that can form a self-locking with the retaining spring groove 221.

[0066] Furthermore, the inner sleeve 2 of this embodiment can be an inner aluminum sleeve, specifically a thin aluminum inner sleeve 2; the one-way valve core 3 can be a phenolic plastic one-way valve core 3, and the structure of the one-way flow valve can refer to the prior art, and this embodiment will not be described in detail here.

[0067] This embodiment exemplifies the casting process of the floating collar as follows:

[0068] (1) The inner sleeve 2 and the check valve core 3 are fixed in the middle of the housing 1 of the floating collar by a mold according to the design position of the assembly drawing;

[0069] (2) Filling and pouring the oil well cement 5 slurry from top to bottom into the annulus between the check valve core 3 and the housing 1;

[0070] (3) After filling to a preset height, a sealing baffle 4 is installed between the housing 1 and the check valve core 3. Both inner and outer ends of the sealing baffle 4 are provided with sealing rings 41 that cooperate with the check valve core 3 and the housing 1 to enhance the sealing between the check valve core 3 and the annulus of the housing 1;

[0071] (4) Continue pouring oil well cement 5 slurry in the annulus above the sealing baffle 4 until it is flush with the upper end of the inner sleeve 2;

[0072] (5) Waiting for a preset time for setting the oil well cement slurry at room temperature to form the floating collar product of this embodiment; wherein the preset waiting time for setting can be more than 10 days.

[0073] The floating collar of this embodiment is mainly used in cementing construction, and its use method is described as follows:

[0074] (1) Connect the float collar to the casing string and lower it to the designed position;

[0075] (2) The front end of the drill bit is connected to the matching inner tube cementing plug 7 and lowered into the casing. When the plug is inserted into the inner sleeve 2, the drill bit 3-5t is pressed down to form a seal. Then, cement slurry is injected into the drill bit. The structural diagram of the inner tube cementing plug and the inner sleeve of the floating collar forming a seal is shown in FIG. Figure 5 As shown;

[0076] (3) When cement slurry is seen returning from the casing and the wellbore annulus, the drilling tool is removed from the wellhead and the drill pipe cement head is used to insert the drill pipe plug 6. Clean water is used to displace the plug to the floating collar position to press and form a self-locking state. The structural diagram of the drill pipe plug 6 in the self-locking state after being pressed is shown in FIG. Figure 6 As shown;

[0077] (4) Return water to observe the backflow of cement slurry. After the backflow is cut off, the drilling tool and the inner pipe cementing plug 7 are lifted up. After the inner pipe column cement plug is pulled out, the structural diagram of the floating collar in the well state is shown in FIG. Figure 7 As shown;

[0078] (5) Later, use a drill bit to drill out the internal material and rubber plug of the float collar.

[0079] Based on the same inventive concept, the embodiment of the utility model also provides a cementing casing system, including: a casing, a drilling tool, an inner pipe cementing plug and the above-mentioned floating collar;

[0080] The lower end of the casing is connected to the upper end of the shell of the floating collar;

[0081] The inner tube cementing plug and the drilling tool are arranged in the casing, and the upper end of the inner tube cementing plug is connected with the lower end of the drilling tool, and the lower end is plugged with the first hole section of the floating collar.

[0082] In one embodiment, the cementing casing system of this embodiment may further include: a control unit;

[0083] The control unit is used to monitor whether the cement slurry in the casing and the wellbore annulus meets the preset requirements, and control the drill pipe rubber plug to be put into the drilling tool after the cement slurry meets the preset requirements; the preset requirement is: cement slurry returns from the casing and the wellbore annulus.

[0084] Regarding the cementing casing system in the above embodiment, the specific usage thereof has been described in detail in the embodiment related to the floating collar, and will not be elaborated here.

[0085] The above-mentioned floating collar of the embodiment of the utility model can specifically adopt oil well cement casting + phenolic plastic single flow valve core + thin aluminum insert structure as the internal structure of the floating collar. The internal material is easy to drill out, which can ensure the timeliness of PDC drillability. At the same time, the high-strength oil well cement can bear the pressure that meets the industry standards. In addition, a drill pipe rubber plug sealing part and a retaining ring groove are reserved at the lower part of the inner sleeve of the floating collar to achieve the sealing and self-locking of the floating collar. When the floating collar is used, a drill pipe rubber plug is put into the drill tool to scrape the cement slurry on the inner wall of the drill tool, ensuring that there is no cement inside the drill tool and avoiding plugging in the pipe at a later time. At the same time, the collision and self-locking of the drill pipe rubber plug and the floating collar can avoid the occurrence of emptying and can further prevent the backflow of cement slurry.

[0086] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0087] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than those clearly stated in each claim. On the contrary, as reflected in the attached claims, the utility model is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the attached claims are hereby expressly incorporated into the detailed description, with each claim acting alone as a separate preferred embodiment of the utility model.

[0088] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A floating collar, characterized in that: include: A housing and an inner sleeve and a check valve core arranged in the housing; The check valve core is arranged below the inner sleeve, and the space between the inner wall of the housing and the outer wall of the inner sleeve, and between the inner wall of the housing and the check valve core is filled with oil well cement; The inner sleeve comprises a first hole section and a second hole section, and the aperture of the first hole section is larger than the aperture of the second hole section; The first hole section is used to cooperate with the inner pipe cementing plug, and the second hole section is used to cooperate with the drill pipe plug. The second hole section is provided with a retaining ring groove to cooperate with the retaining ring of the drill pipe plug to limit the drill pipe plug.

2. The floating collar according to claim 1, characterized in that: Also includes: Sealing bulkhead; The sealing partition is arranged between the housing and the check valve core, and a sealing ring is arranged between the sealing partition and the housing, and between the sealing partition and the check valve core.

3. The floating collar according to claim 2, characterized in that: The thickness of the sealing partition is 15mm-25mm.

4. The floating collar according to claim 1, characterized in that: The first hole section includes a tapered hole section and a cylindrical section; One end of the cylindrical section is connected to the end of the tapered hole section with a smaller diameter, and the other end is connected to the second hole section. One or more of threads, patterns or grooves are arranged on the outer surface of the cylindrical section.

5. The floating collar according to claim 4, characterized in that: When a thread is provided on the outer surface of the cylindrical segment, the thread is a right-handed trapezoidal thread, and the pitch of the thread is 5-10 mm and the diameter is 100-110 mm.

6. The floating collar according to claim 1, characterized in that: A boss is arranged on the outer wall of the second hole section, a plurality of through holes are arranged on the boss, and the through holes are filled with oil well cement.

7. The floating collar according to claim 1, characterized in that: Also includes: Drill pipe plug; The drill pipe rubber plug comprises: a frame, a leather cup sleeved on the upper part of the frame, and a sealing ring installation groove and a retaining spring arranged at the lower part of the frame; The skeleton is used to cooperate with the second hole section to press and seal the second hole section.

8. The floating collar according to any one of claims 1 to 7, characterized in that: The inner insert sleeve is an inner insert aluminum sleeve.

9. A cementing casing system, characterized in that: include: Casing, drilling tool, inner pipe cementing plug and floating collar as claimed in any one of claims 1 to 8; The lower end of the casing is connected to the upper end of the shell of the floating collar; The inner tube cementing plug and the drill tool are arranged in the casing, and the upper end of the inner tube cementing plug is connected to the lower end of the drill tool, and the lower end is plugged into the first hole section of the floating collar.

10. The cementing casing system according to claim 9, characterized in that: Also includes: Control unit; The control unit is used to monitor whether the cement slurry in the casing and the wellbore annulus meets the preset requirements, and control the drill pipe rubber plug to be put into the drilling tool after the cement slurry meets the preset requirements; the preset requirements are: cement slurry returns from the casing and the wellbore annulus.

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