Multifunctional conduit head wellhead device for single cylinder and multiple wells

Abstract

The invention relates to the field of oil field wellhead devices, and discloses a multifunctional conduit head wellhead device for a single cylinder and multiple wells. A plurality of well slots are formed in a conduit head body, mandrel type casing hanger bodies are mounted in the well slots, notches are formed in the tops of the well slots, and annular limiting slots are formed in the inner walls of the upper parts of the well slots; a limiting pin is arranged on a side wing of the mandrel type casing hanger body, an adjusting bolt is installed on the circumference of the lower portion of the guide pipe head body, the bottom of the guide pipe head body and a marine riser are welded and sealed in a full-circumference mode, a supporting rib plate is welded between the guide pipe head body and the marine riser, and a fast-assembly mud pipeline is arranged on the side wing of the guide pipe head body. The well cementation connecting device body is installed on the upper portion of the mandrel type casing hanger body. The well cementation connecting device body is connected with a slurry pipeline. Casing pipe well cementation slurry enters and exits smoothly, and the construction efficiency is greatly improved; the stability of the whole wellhead device is enhanced, the use cost and the maintenance difficulty are reduced, and the installation is simple, convenient, feasible, safe and reliable.

Description

Technical Field

[0001] The invention relates to the field of oilfield wellhead devices, and in particular to a multifunctional catheter head wellhead device for single-barrel multi-wells. Background Art

[0002] In order to improve the efficiency of oil and gas production and enhance the space utilization of offshore platforms, oil fields have widely adopted single-drum multi-well technology. During the on-site installation of single-drum multi-well wellhead devices on offshore platforms, after running multiple spacer pipes, multiple spacer pipes need to be cemented simultaneously. During this process, the buoyancy generated by the mud will cause the casing to float up, seriously affecting the difficulty of construction. Figure 11 ) It is necessary to connect the casing from the drilling platform to the upper part of the core shaft hanger, and then inject mud from the casing. The process is cumbersome and affects the construction efficiency; and the sealing of the catheter head body and the watertight pipe often uses a large-diameter sealing ring, which increases the use cost and maintenance cost. Summary of the Invention

[0003] In order to overcome the defects of the prior art, the present invention provides a multifunctional catheter head wellhead device for single-tube multi-wells, and its technical solution is as follows: A multifunctional guide tube head wellhead device for single-tube multi-wells, comprising a guide tube head body, a watertight riser, a mandrel-type casing hanger assembly, and a cementing connection device assembly; the mandrel-type casing hanger assembly comprises a mandrel-type casing hanger body, and the cementing connection device assembly comprises a cementing connection device body; a plurality of well slots are provided inside the guide tube head body, and the mandrel-type casing hanger assembly is installed in the well slots, the well slot top is provided with a notch, the upper inner wall is provided with an annular limit groove, the side flanks of the mandrel-type casing hanger body are provided with threaded holes and are fixed with limited screws through them The limit pin is lowered from the notch and then rotated into the limit groove along with the core shaft casing hanger body. The lower circumference of the guide tube head body is evenly provided with threaded holes and adjusting bolts are installed through them. The bottom and the watertight pipe are fixed and sealed around the entire circumference. The side of the guide tube head body is reserved with a mud return outlet for connecting the quick-install mud pipeline. The lower part of the core shaft casing hanger body is installed with a vacant casing through the provided casing thread, and the upper part is installed with the cementing connection device body through the provided lifting thread. The cementing connection device body is installed with a mud pipeline joint for connecting the mud pipeline through a connecting short circuit.

[0004] Furthermore, the bottom of the catheter head body and the watertight pipe are fixed and sealed by welding.

[0005] Furthermore, support ribs are welded between the catheter head body and the watertight pipe.

[0006] Furthermore, a reserved pressure test hole is provided on the side wing of the catheter head body, and a screw plug is installed at the outer end of the pressure test hole after the pressure test is completed; after the adjusting bolt is removed after the adjustment task is completed, a sealing gasket and a sealing bolt are installed.

[0007] Furthermore, after the mandrel-type casing hanger body carries the limit pin and is rotated into position, a limit block is placed in the notch at the top of the well slot.

[0008] Furthermore, the upper and lower parts of the mandrel-type casing hanger body each have four S seals.

[0009] Furthermore, two eye screws are provided on the upper end surface of the cementing connection device body.

[0010] Furthermore, an O-ring is provided around the upper portion of the cementing connection device body.

[0011] Furthermore, when the placeholder casing is lowered, the lower portion of the mandrel-type casing hanger assembly is connected to the placeholder casing, and the upper portion is connected to the lifting casing through the mandrel-type casing hanger delivery and retrieval tool.

[0012] Furthermore, the mandrel-type casing hanger assembly suspends the surface casing via the surface casing slip hanger located on the inner step thereof.

[0013] Compared with the prior art, the present invention has the following beneficial technical effects: 1. The present invention connects the mud pipeline through the mud pipeline joint of the cementing connection device body and connects the quick-install mud pipeline through the mud return outlet reserved on the side of the catheter head body, ensuring smooth inflow and outflow of mud during cementing of the occupying casing, achieving significant cementing effect and greatly improving construction efficiency.

[0014] 2. The guide tube head body and the watertight pipe of the present invention are sealed by welding, and the stability of the overall wellhead device is improved by adding supporting ribs, thereby reducing the cost of use and the difficulty of maintenance.

[0015] 3. The present invention makes the installation of the mandrel type casing hanger body simple, easy, safe and reliable through the combined design of the limit pin, the notch, the limit groove and the limit block.

[0016] 4. The present invention adopts a combined design of an adjusting bolt, a sealing gasket and a sealing bolt, which not only facilitates the adjustment of the position of the catheter head body so that it remains coaxial with the watertight pipe, but also solves the sealing problem after the adjusting bolt is removed.

[0017] 5. The present invention improves the sealing performance of the installation of the mandrel-type casing hanger body and the cementing connection device body through the combined design of the S seal and the O-ring.

[0018] 6. The present invention facilitates the overall lifting of the cementing connection device assembly through the lifting eye screw.

[0019] 7. The present invention is convenient for hanging both the placeholder casing and the surface casing, thus saving space in the wellhead device and improving installation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the structure of the mandrel type casing hanger assembly of the present invention; Figure 2 It is a structural schematic diagram of the cementing connection device assembly of the present invention; Figure 3 A schematic diagram of adjusting the position of the catheter head body, installing it to the watertight pipe, and welding it according to the present invention; Figure 4 This is a schematic diagram of installing the sealing bolt after the welding of the catheter head body of the present invention is completed; Figure 5 This is a schematic diagram of the quick-install mud pipeline installed on the side wing of the catheter head body of the present invention; Figure 6 A schematic diagram of installing a mandrel-type casing hanger according to the present invention; Figure 7 A top view schematic diagram of a rotating mandrel casing hanger according to the present invention; Figure 8 This is a schematic diagram of installing a cementing connection device on a mandrel-type casing hanger according to the present invention; Figure 9 A schematic diagram of installing a surface casing slip hanger on a mandrel-type casing hanger according to the present invention; Figure 10 This is an isometric view of the multifunctional catheter head wellhead assembly of the present invention; Figure 11 This is a schematic diagram of the installation of a traditional conductor head and riser; In the figure: 1-S seal, 2-mandrel casing hanger body, 3-connecting screw, 4-limiting pin, 5-mud pipeline joint, 6-connecting short circuit, 7-lifting eye screw, 8-O-ring, 9-cementing connection device body, 10-guide tube head body, 11-screw plug, 12-adjusting bolt, 13-support rib, 14-water-relief pipe, 15-sealing gasket, 16-sealing bolt, 17-quick-install mud pipeline, 18-lifting casing, 19-mandrel casing hanger delivery and retrieval tool, 20-mandrel casing hanger assembly, 21-occupying casing, 22-limiting block, 23-mud pipeline, 24-cementing connection device assembly, 25-surface casing, 26-surface casing slip hanger, 27-notch, 28-lifting thread, 29-casing thread, 30-well slot, 31-limiting slot. DETAILED DESCRIPTION

[0021] The present invention is described in detail below with reference to specific embodiments and accompanying drawings. Example 1

[0022] See also Figures 1 to 10A multifunctional guide tube head wellhead device for single-tube multi-wells, comprising a guide tube head body 10, a watertight riser 14, a mandrel-type casing hanger assembly 20, and a cementing connection device assembly 24; the mandrel-type casing hanger assembly 20 comprises a mandrel-type casing hanger body 2, and the cementing connection device assembly 24 comprises a cementing connection device body 9; a plurality of well slots 30 are provided inside the guide tube head body 10, and the mandrel-type casing hanger assembly 20 is installed in the well slots 30, the well slots 30 are provided with notches 27 at the top and an annular limit groove 31 on the upper inner wall, and the mandrel-type casing hanger body 2 has threaded holes on its flanks and is fixed to a limited position by connecting screws 3. Pin 4, after the limit pin 4 is lowered from the notch 27, it rotates with the core shaft casing hanger body 2 into the limit groove 31, the lower circumference of the guide tube head body 10 is evenly provided with threaded holes and the adjusting bolts 12 are installed through them, the bottom and the watertight pipe 14 are fixed and sealed all around, and the side of the guide tube head body 10 is reserved with a mud return outlet for connecting the quick-install mud pipeline 17; the lower part of the core shaft casing hanger body 2 is installed with a placeholder casing 21 through the provided casing thread 29, and the upper part is installed with the cementing connection device body 9 through the provided lifting thread 28, and the cementing connection device body 9 is installed with a mud pipeline joint 5 for connecting the mud pipeline 23 through the connecting short circuit 6. Example 2

[0023] See also Figures 1 to 10 A multifunctional catheter head wellhead device for single-tube multi-wells, based on the technical solution described in Example 1, adopts welding to fix and seal the bottom of the catheter head body 10 and the watertight pipe 14; supporting ribs 13 are welded between the catheter head body 10 and the watertight pipe 14 to increase stability. Example 3

[0024] See also Figures 1 to 10 A multifunctional catheter head wellhead device for single-tube multi-wells, based on the technical solution described in Example 1, has a reserved pressure test hole on the side of the catheter head body 10. After the pressure test is completed, a screw plug 11 is installed at the outer end of the pressure test hole; after the adjustment bolt 12 is removed after the adjustment task is completed, a sealing gasket 15 and a sealing bolt 16 are installed to ensure a reliable seal. Example 4

[0025] See also Figures 1 to 10 A multifunctional casing head wellhead device for single-bore multi-wells, based on the technical solution described in Example 1, wherein a mandrel-type casing hanger body 2 carrying a limit pin 4 is rotated into position and a limit block 22 is placed in the notch 27 at the top of the well slot 30 to prevent the mandrel-type casing hanger body 2 from falling out. Example 5

[0026] See also Figures 1 to 10A multifunctional casing head wellhead device for single-bore multi-wells, based on the technical solution described in Example 1, has four S seals on the upper and lower parts of the mandrel-type casing hanger body 2. The S seals are resistant to high temperatures and corrosion and can maintain stable performance under high pressure and extreme working conditions. Example 6

[0027] See also Figures 1 to 10 A multifunctional catheter head wellhead device for single-tube multiple wells, based on the technical solution described in Example 1, has two lifting eye screws 7 provided on the upper end surface of the cementing connection device body 9 to facilitate overall lifting; an O-ring 8 is provided around the upper portion of the cementing connection device body 9 to ensure sealing during installation. Example 7

[0028] See also Figures 1 to 10 A multifunctional casing head wellhead device for single-tube multi-wells, based on the technical solution described in Example 1, when the placeholder casing 21 is lowered, the lower part of the mandrel casing hanger assembly 20 is connected to the placeholder casing 21, and the upper part is connected to the lifting casing 18 through the mandrel casing hanger delivery tool 19. Example 8

[0029] See also Figures 1 to 10 A multifunctional casing head wellhead device for single-bore multi-wells, based on the technical solution described in Example 1, a mandrel-type casing hanger assembly 20 hangs the surface casing 25 through the surface casing slip hanger 26 located on the inner step thereof.

[0030] In order to enable those skilled in the art to better understand the present invention, the basic working process is briefly described as follows: Reference Figure 3 First, hoist the catheter head body 10 horizontally so that it sits steadily on the watertight pipe 14, install the screw plug 11 to the reserved pressure test hole, install the adjusting bolt 12 at the threaded holes evenly distributed around the bottom of the catheter head body 10, and adjust the position of the catheter head body 10 so that it remains coaxial with the watertight pipe 14; weld the bottom of the catheter head body 10 to the watertight pipe 14 around the entire circumference, and weld the supporting ribs 13, refer to Figure 11 Compared with the traditional installation of the conduit head and the watertight pipe, the large-size sealing rubber ring and grease injection are used to improve the installation efficiency and reduce the cost. Figure 4-5 , remove the adjusting bolt 12 and install the sealing gasket 15 and the sealing bolt 16, and install the quick-install mud pipeline 17 on the side of the catheter head body 10.

[0031] Reference Figure 6, connect the mandrel casing hanger assembly 20 with the occupying casing 21, then connect the lifting casing 18 with the mandrel casing hanger delivery tool 19, and then connect the mandrel casing hanger assembly 20 with the mandrel casing hanger delivery tool 19.

[0032] Reference Figure 7 , slowly lower the occupying casing 21. During the lowering process, the limit pin 4 should be aligned with the notch on the catheter head body 10. After lowering into place, rotate the mandrel type casing hanger assembly 20 90°, and place the two limit blocks 22 into the notch 27 of the catheter head body 10 respectively. Observe the marks A and B above the mandrel type casing hanger assembly 20 to clearly know the rotation angle of the mandrel type casing hanger assembly 20.

[0033] Reference Figure 8 After the dummy casings 21 and mandrel-type casing hanger assemblies 20 in all well slots 30 have been lowered, the cementing connector assembly 24 is installed on the mandrel-type casing hanger assembly 20 and connected to the mud line 23 to begin cementing operations. Mud and waste liquid generated during the lowering of the dummy casings 21 and cementing operations are returned to the mud pit via the quick-install mud line 17 on the side of the guide tube head body 10, significantly reducing cementing time and ease of operation.

[0034] Reference Figure 9 The surface casing 25 is suspended by a surface casing slip hanger 26 located on the inner step of the mandrel casing hanger assembly 20, which saves space in the wellhead device and improves the efficiency of installation.

Claims

1. A multifunctional casing head wellhead device for single-tube multi-wells, comprising a casing head body, a watertight riser, and a mandrel-type casing hanger assembly, characterized in that: It also includes a cementing connection device assembly; the core shaft casing hanger assembly includes a core shaft casing hanger body, and the cementing connection device assembly includes a cementing connection device body; a number of well grooves are opened inside the guide tube head body, and the core shaft casing hanger assembly is installed in the well groove, the top of the well groove is provided with a notch, the upper inner wall is provided with an annular limit groove, the side wing of the core shaft casing hanger body has a threaded hole and a limit pin is fixed by a connecting screw. After the limit pin is lowered from the notch, it rotates with the core shaft casing hanger body into the limit groove, the lower part of the guide tube head body is evenly provided with threaded holes and adjusting bolts are installed thereby, the bottom and the watertight pipe are fixed and sealed all around, and a mud return outlet is reserved on the side wing of the guide tube head body for connecting a quick-install mud pipeline; the lower part of the core shaft casing hanger body is installed with a occupier casing through the set casing thread, and the upper part is installed with the cementing connection device body through the set lifting thread, and the cementing connection device body is installed with a mud pipeline joint for connecting the mud pipeline through a connecting short circuit.

2. The multifunctional catheter head wellhead device for single-tube multi-wells according to claim 1 is characterized in that: The bottom of the catheter head body and the watertight pipe are fixed and sealed by welding.

3. The multifunctional catheter head wellhead device for single-tube multi-wells according to claim 1 is characterized in that: Support ribs are welded between the catheter head body and the watertight pipe.

4. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1 is characterized in that: The side wing of the catheter head body is provided with a reserved pressure test hole. After the pressure test is completed, a screw plug is installed at the outer end of the pressure test hole; after the adjustment bolt is removed after the adjustment task is completed, a sealing gasket and a sealing bolt are installed.

5. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1 is characterized in that: The mandrel type casing hanger body carries the limit pin and is rotated into position, and a limit block is placed in the notch at the top of the well slot.

6. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1 is characterized in that: The upper and lower parts of the mandrel-type casing hanger body are each provided with four S seals.

7. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1 is characterized in that: The upper end surface of the cementing connection device body is provided with two lifting eye screws.

8. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1 is characterized in that: An O-type sealing ring is provided around the upper part of the cementing connection device body.

9. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1, characterized in that: When the placeholder casing is lowered, the lower part of the mandrel-type casing hanger assembly is connected to the placeholder casing, and the upper part is connected to the lifting casing through the mandrel-type casing hanger delivery and withdrawal tool.

10. The multifunctional catheter head wellhead device for single-tube multiple wells according to claim 1, characterized in that: The mandrel type casing hanger assembly suspends the surface casing through the surface casing slip hanger located on the inner step of the mandrel type casing hanger assembly.

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