Method for manufacturing a jack-up derrick base section

Abstract

This invention discloses a method for manufacturing a self-elevating derrick base section, comprising the following steps: 1) manufacturing the upper left base section, middle left base section, lower left base section, and upper right base section, middle right base section, and lower right base section respectively, and machining guide roller mounting holes for each; 2) placing the middle left base section, middle right base section, and back crossbeam on a rigid platform, adjusting the level, and assembling them into a component; 3) assembling the upper left base section and upper right base section, and continuing to assemble the back beam and diagonal tie rod; then welding the upper left base section and middle left base section, and the upper right base section and middle right base section respectively, to obtain the assembly; 4) placing the assembly horizontally on a support according to the projected dimensions, placing the lower left base section and lower right base section on a triangular support, and installing the left and right support legs on positioning fixtures respectively. After the relevant dimensions meet the requirements, final welding is performed. This method, by manufacturing the upper half of the base section as a whole, can control the dimensions of the upper half of the base section to meet the requirements, reducing the manufacturing difficulty.

Description

Technical Field

[0001] This invention belongs to the field of oil drilling and production equipment manufacturing technology, and relates to a method for manufacturing a self-elevating derrick base section. Background Technology

[0002] The self-elevating derrick is a new type of derrick that has been gradually adopted in recent years. The derrick is divided into 5 to 6 sections, with the derrick body installed on a base section. The derrick body can be assembled in sections at a low position, powered by a drilling winch or hydraulic winch. Lifting devices and guide rollers are located on the base section, and the H-beams of the rear columns of each section guide the lifting and installation of each section. Its characteristics include a high degree of modularity, lightweight individual modules, and a small installation footprint. The base section is mainly divided into left and right sections, connected by components such as back crossbeams and diagonal braces to form the frame.

[0003] Currently, the conventional method of fabricating left and right base sections separately, followed by side placement and installation of relevant back crossbeams and diagonal braces, often leads to the following problems due to assembly accuracy and welding deformation: 1) The dimensions of the upper half of the left and right base sections (the difference in left-right spacing and diagonal dimensions) cannot be simultaneously satisfied with the dimensions at the lower support, easily causing the cross-sectional dimensions of the base sections to exceed tolerances, resulting in jamming during the derrick's lifting process; 2) After the derrick is lifted and installed, the center of the top wellhead is skewed. Therefore, there is an urgent need to design a method for fabricating the base sections of a self-elevating derrick for oil drilling rigs to overcome the above shortcomings. Summary of the Invention

[0004] The purpose of this invention is to provide a method for manufacturing a self-elevating derrick base section, which solves the problem of jamming during the derrick lifting process caused by out-of-tolerance cross-sectional dimensions of the base section in the prior art.

[0005] The technical solution adopted in this invention is a method for manufacturing a self-elevating derrick base section, which is implemented according to the following steps:

[0006] Step 1: Using existing processes, fabricate the upper left base segment, middle left base segment, lower left base segment, upper right base segment, middle right base segment, and lower right base segment respectively, and machine the guide roller mounting holes on the upper left base segment and upper right base segment respectively;

[0007] Step 2: Place the left base section, right base section, and back crossbeam on a rigid platform, adjust their level, and then assemble them into a component using bolts.

[0008] Step 3: On the components from Step 2, assemble the left and right base sections. After checking that the positional dimensions of the left and right base sections meet the requirements, continue assembling the back beam and diagonal tie rod. Then, weld the connecting welds between the left and right base sections and between the right and right base sections respectively to obtain the assembled parts.

[0009] Step 4: Based on the projected dimensions and positions of each component in the derrick base section on the platform, place the assembly obtained in Step 3 horizontally onto the support. Place the lower left and lower right base sections onto the triangular support. Install the left and right support legs onto the positioning fixtures respectively. After checking that the relevant dimensions meet the requirements, perform the final welding in this state to complete the assembly.

[0010] The beneficial effects of this invention are that by manufacturing the upper half of the base section as a whole, the dimensions of the upper half of the base section can be controlled to meet the requirements, ensuring the manufacturing quality, making the derrick lifting process smooth and unobstructed, and reducing the manufacturing difficulty. Attached Figure Description

[0011] Figure 1 This is a three-dimensional schematic diagram of the self-elevating derrick base section of an oil drilling rig produced by the method of this invention;

[0012] Figure 2 This is a schematic diagram of the structure of the upper half of the left and right base segments produced by the method of the present invention;

[0013] Figure 3 This is a schematic diagram of the structure of the lower half of the left and right base segments produced by the method of the present invention;

[0014] Figure 4 This is a schematic diagram of assembling the middle part of the left and right base sections and the back crossbeam using the method of the present invention;

[0015] Figure 5 This is a top view of the upper half of the base segment assembled by the method of the present invention;

[0016] Figure 6 This is a schematic diagram of the horizontal assembly of the base segment using the method of the present invention;

[0017] Figure 7 yes Figure 6 Partial top view (support not shown).

[0018] In the diagram, 1. Left base segment, 2. Right base segment, 3. Back crossbeam, 4. Back beam, 5. Diagonal tie rod, 6. Tooling support, 7. Tooling lug, 8. Support, 9. Triangular support, 101. Upper left base segment, 102. Middle left base segment, 103. Lower left base segment, 104. Left support leg, 201. Upper right base segment, 202. Middle right base segment, 203. Lower right base segment, 204. Right support leg, A. Wellhead centerline I, B. Wellhead centerline II, C. Lug hole centerline. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0020] like Figure 1 The image shows a typical structure of an existing derrick.

[0021] Reference Figure 2 , Figure 3 , Figure 4 , Figure 5 The self-elevating derrick base section manufactured by the method of the present invention comprises two main parts: a left base section 1 and a right base section 2. The left base section is an integral welded structure composed of the upper left base section 101, the middle left base section 102, the lower left base section 103, and the left support leg 104. The right base section 2 is an integral welded structure composed of the upper right base section 201, the middle right base section 202, the lower right base section 203, and the right support leg 204. Finally, it is horizontally connected and fixed by components such as the back crossbeam and the diagonal tie rod.

[0022] The method of this invention involves first fabricating the upper half of the base segment, and then assembling it with the lower half of the base segment, specifically implemented according to the following steps:

[0023] Step 1: Using existing processes, fabricate the upper left base segment 101, middle left base segment 102, lower left base segment 103, and the upper right base segment 201, middle right base segment 202, and lower right base segment 203 respectively. Also, machine the guide roller mounting holes on the upper left base segment 101 and the upper right base segment 201 respectively. (See...) Figure 2 , Figure 3 ;

[0024] Step 2: Place the left base segment 102, the right base segment 202, and the back crossbeam 3 on the rigid platform. After adjusting the level, assemble them into a component using bolts. (See...) Figure 4 ;

[0025] Step 3: On the components from Step 2, assemble the left base section upper 101 and the right base section upper 201. After checking that the positional dimensions of the left base section upper 101 and the right base section upper 201 meet the requirements, continue assembling the back beam 4 and the diagonal tie rod 5; then weld the connecting welds between the left base section upper 101 and the left base section middle 102, and between the right base section upper 201 and the right base section middle 202, respectively, to obtain the assembled parts, see... Figure 5 ;

[0026] In step 3, before welding, check the following process dimensions: whether the upper 101 of the left base section and the upper 201 of the right base section are vertical; the distance between the upper 101 of the left base section and the upper 201 of the right base section; and the difference in diagonal dimensions of the cross-sections of the upper 101 of the left base section and the upper 201 of the right base section. If the above dimensions fully meet the process requirements, the hoisting process of the derrick can be guaranteed to be smooth and without obstruction.

[0027] Step 4: Based on the projected dimensions and positions of each component in the derrick base section on the platform, place the assembly obtained in Step 3 horizontally onto the support 8. Place the lower left base section 103 and the lower right base section 203 onto the triangular support 9. Install the left support leg 104 and the right support leg 204 onto the positioning fixtures. After checking that the relevant dimensions meet the requirements, perform the final welding in this state. See [link to documentation]. Figure 6 , Figure 7 .

[0028] In step 4, ensure the following process requirements are met:

[0029] 4.1) In the projected dimensions, the center line of the wellhead (II, B) is perpendicular to the center line of the lug hole (C). This requirement ensures that after the base section is installed on site, the center of the wellhead is centered and does not deviate in the left and right directions, which is a prerequisite for the center of the wellhead to be centered in the left and right directions after the overall derrick is installed.

[0030] 4.2) In the projected dimensions, the centerline I(A) of the wellhead is horizontal. This requirement ensures that after the base section is installed on site, the center of the wellhead is centered and does not deviate in the front-back direction. This is a prerequisite for the center of the wellhead to be centered in the front-back direction after the overall derrick is installed.

[0031] 4.3) The positioning fixture consists of a general-purpose fixture support 6 and a fixture lug 7 bolted to the fixture support 6. After the fixture lugs 7 at both ends are installed, their pin holes should be checked to be coaxial and at the same height.

Claims

1. A method for manufacturing a self-elevating derrick base section, characterized in that, The specific steps are as follows: Step 1: Using existing processes, fabricate the upper left base segment (101), middle left base segment (102), lower left base segment (103), upper right base segment (201), middle right base segment (202), and lower right base segment (203), and machine the guide roller mounting holes on the upper left base segment (101) and upper right base segment (201) respectively; Step 2: Place the left base section (102), the right base section (202), and the back crossbeam (3) on the rigid platform, adjust the level, and assemble them into a component with bolts; Step 3: On the components from Step 2, assemble the left base section (101) and the right base section (201). After checking that the position and dimensions of the left base section (101) and the right base section (201) meet the requirements, continue assembling the back beam (4) and the diagonal tie rod (5). Then, weld the connecting welds between the left base section (101) and the left base section (102) and between the right base section (201) and the right base section (202) to obtain the assembled parts. Step 4: Based on the projected dimensions and positions of each component in the derrick base section on the platform, place the assembly obtained in Step 3 horizontally onto the support (8), place the lower left base section (103) and the lower right base section (203) onto the triangular support (9), and install the left support leg (104) and the right support leg (204) onto the positioning fixture respectively. After checking that the relevant dimensions meet the requirements, perform the final welding in this state to complete the assembly.

2. The method of fabricating a jack-up rig cellar section of claim 1, wherein: In step 3, before welding, check the following process dimensions: whether the left base section (101) and the right base section (201) are vertical; the distance between the left base section (101) and the right base section (201); and the difference in diagonal dimensions between the cross sections of the left base section (101) and the right base section (201).

3. The method for manufacturing the self-elevating derrick base section according to claim 1, characterized in that: In the aforementioned projection size position, the projection line wellhead centerline II (B) is perpendicular to the ear seat hole centerline (C).

4. The method for manufacturing the self-elevating derrick base section according to claim 1, characterized in that: In the projected dimensions, the wellhead centerline I(A) is horizontal.

5. The method for manufacturing the self-elevating derrick base section according to claim 1, characterized in that: The positioning fixture consists of a general-purpose fixture support (6) and a fixture lug (7) bolted to the fixture support (6). After the fixture lugs (7) at both ends are installed, their pin holes should be checked to be coaxial and at the same height.

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