Cold machining circular milling cutter mechanical slotted screen pipe

Abstract

A cold machining circular milling cutter mechanical slotted screen pipe belongs to the technical field of oil and gas exploitation process, and comprises a base pipe, a support rib, a support ring and a slotted outer pipe, the slotted outer pipe is sleeved outside the base pipe, the base pipe is connected with the slotted outer pipe through the support rib and the support ring, the support rib penetrates through the gap of the slotted outer pipe and is welded on the base pipe, and the support ring is welded on the base pipe. The supporting ring is welded to the base pipe and connected with the gap outer pipe. According to the screen pipe, the cold machining mechanical slotting technology and the circular milling cutter machining mode are adopted, the overall strength of the screen pipe is improved, the sand prevention efficiency is improved to a great extent, and the problems that when a laser slotting screen pipe horizontal well descends, micro cracks and hole blasting exist, consequently, the seam width seriously exceeds the standard, and heat dissipation is difficult are solved. According to the high-strength mechanical slotted screen pipe for the horizontal well, the external extrusion resistance, the tensile strength and the roughness are superior to those of a laser slotted screen pipe, the service life is long, and the damage rate of the screen pipe is greatly reduced.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas extraction technology, specifically relating to a cold-working circular milling cutter for mechanically cutting slotted screens. Background Technology

[0002] Slotted screen completion is a relatively simple and practical well completion technology. It overcomes the problems of complex construction and low effectiveness of wire-wound screen sand control in deviated wells, and features simple sand control process, convenient operation, and low cost, making it widely used in major oilfields. In the mid-to-late 1990s, laser-processed slotted liners were widely used in China; however, due to the inherent characteristics of laser processing, the following problems exist:

[0003] This increases the likelihood of microcracks forming around the cut when the horizontal well liner is run into the well. Since laser processing is a thermal process, it inevitably creates a heat-affected zone near the cut during processing. Medium-carbon casing develops a surface hardened layer, further increasing the possibility of microcracks forming around the cut when the horizontal well liner is run into the well.

[0004] The presence of more than 2% of burst holes during laser processing and the significant exceedance of kerf widths caused by processing issues increase the difficulty of sand control. Furthermore, the laser-processed kerf end face has low surface finish due to the hot processing method, making self-cleaning difficult. Even if surface repair welding and polishing are used after burst holes, the welded area is only surface-welded, lacking internal connection, and the welding stress in the heat-affected zone reduces strength, making it difficult to guarantee that the pipe will not encounter problems during its installation in the well.

[0005] Continuous hot processing makes heat dissipation in the inner cavity of the pipe difficult, changes the structure of the original substrate, and causes severe deformation of the slotted liner due to huge thermal stress. The straightened slotted screen pipe has a lot of residual stress. The hot processing residue in the inner cavity is difficult to remove, making it difficult to operate inside the pipe.

[0006] In the early stages, horizontal wells that used laser-cut slotted screens for more than 10 years experienced a large number of damage and sand production issues. For example, in a certain block of the Shuguang Oilfield in Liaohe Oilfield, horizontal wells that used slotted screens for completion before 2015 had a damage rate as high as 58%. The damage to the screens was mainly manifested as punctures and deformation of the slots. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes a cold-worked circular milling cutter mechanically slotted screen pipe. The high-strength mechanically slotted screen pipe for horizontal wells consists of a base pipe, supporting ribs, supporting rings, and a slotted outer pipe. The slotted outer pipe is sleeved outside the base pipe. The base pipe is connected to the slotted outer pipe through the supporting ribs and supporting rings. The supporting ribs pass through the slots of the slotted outer pipe and are welded to the base pipe. The supporting rings are welded to the base pipe and connected to the slotted outer pipe.

[0008] Furthermore, the base tube is made of P110H material.

[0009] Furthermore, the base tube has spiral holes.

[0010] Furthermore, the supporting ribs are welded to the base pipe, with at least three spot welds on each spiral to ensure that there are no gaps between the supporting ribs and the base pipe.

[0011] Furthermore, the outer tube of the slit is made of 316L steel.

[0012] Furthermore, the slit in the outer tube is cut using a mechanical cutting method.

[0013] Furthermore, the slits on the outer tube of the slit are cut using parallel stitching.

[0014] Furthermore, the average hardness of the base tube is basically the same as the average hardness of the cut surface of the slotted outer tube.

[0015] Furthermore, the support ring is welded to the base pipe, and the upper end of the support ring is connected to the outer pipe of the slit to support and fix the outer pipe of the slit.

[0016] Furthermore, the base tube is connected to the next base tube via the upper end of the support ring.

[0017] The beneficial effects of this invention are as follows: This invention provides a high-strength slotted screen pipe for horizontal wells used for sand control. The screen pipe adopts cold working mechanical slotting technology and is processed by a circular milling cutter, which improves the overall strength of the screen pipe and greatly improves the sand control efficiency. It solves the problems of micro-cracks, burst holes leading to serious exceedance of slot width, and difficulty in heat dissipation that occurred when laser-cut slotted screen pipes were run into horizontal wells.

[0018] 1. The invented high-strength mechanically slotted screen pipe for horizontal wells has superior resistance to external extrusion, tensile strength, and roughness compared to laser-slotted screen pipes. It also has a long service life and greatly reduces the damage rate of screen pipes.

[0019] 2. The invented horizontal well high-strength mechanically slotted screen pipe adopts cold-working mechanical slotting technology and circular milling cutter processing method, which avoids the thermal impact of laser-slotted screen pipe on the slot during hot processing and reduces the possibility of micro-cracks around the slot.

[0020] 3. The invented horizontal well high-strength mechanically slotted screen pipe is processed using a cold-working mechanical slotting method, resulting in uniform slot width, smooth surface, high gloss, and self-cleaning function. The mechanical slotting method used in the processing maintains the original structure of the base material and avoids the problem of deformation of the base pipe due to heating. Attached Figure Description

[0021] Figure 1 This is a structural diagram of the high-strength slotted screen pipe for horizontal wells according to the present invention;

[0022] Figure 2This is a schematic diagram of the base tube structure of the present invention;

[0023] Figure 3 A schematic diagram of the circumferential unfolding of the support rib of the present invention;

[0024] Figure 4 Schematic diagram of the support ring structure of the present invention;

[0025] Figure 5 A schematic diagram of the front structure of the slotted outer tube of the present invention;

[0026] Figure 6 A schematic diagram of the side structure of the slit outer tube of the present invention.

[0027] 1. Base tube, 2. Supporting rib, 3. Supporting ring, 4. Outer tube of the gap. Detailed Implementation

[0028] To make the technical means and objectives of this invention easier to understand, the invention is further described below in conjunction with specific embodiments. A cold-worked circular milling cutter mechanically slotted screen pipe for horizontal wells is composed of a base pipe, supporting ribs, supporting rings, and a slotted outer pipe. The slotted outer pipe is sleeved outside the base pipe. The base pipe is connected to the slotted outer pipe through the supporting ribs and supporting rings. The supporting ribs pass through the slots of the slotted outer pipe and are welded to the base pipe. The supporting rings are welded to the base pipe and connected to the slotted outer pipe.

[0029] The base tube is made of P110H material.

[0030] The base tube has spiral holes.

[0031] The supporting ribs are welded to the base pipe, and each spiral has at least 3 spot welds to ensure that there are no gaps between the supporting ribs and the base pipe.

[0032] The outer tube of the slit is made of 316L steel.

[0033] The slit in the outer tube is cut using a mechanical cutting method.

[0034] The slits on the outer tube of the slit are cut using parallel slits.

[0035] The average hardness of the base tube is basically the same as the average hardness of the cut surface of the outer tube.

[0036] Among them, such as Figure 4 As shown, the support ring is welded to the base pipe, and the upper end of the support ring is connected to the outer pipe of the slit to support and fix the outer pipe of the slit.

[0037] The base tube is connected to the next base tube via the upper end of the support ring.

[0038] A type of cold-worked circular milling cutter mechanically slotted screen pipe commonly used in horizontal well sand control construction is a high-strength horizontal well slotted screen pipe. This high-strength mechanically slotted screen pipe for horizontal wells consists of a base pipe, supporting ribs, supporting rings, and an outer slotted pipe. For example... Figure 1 As shown.

[0039] Base tube 1 Figure 2 As shown, it is made of P110H material, with spiral holes, a spiral axial spacing of 60mm, and a hole diameter of 10mm.

[0040] The base pipe 1 and the slotted outer pipe are connected to the support ring 3 via support ribs 2. The support ribs 2 are welded to the base pipe, with at least 3 spot welds on each spiral to ensure no gaps between them and the base pipe. The circumferential unfolded diagram is shown below. Figure 3 As shown;

[0041] The outer tube 4 of the slot is made of 316L steel, and the slots are cut mechanically, with 50 parallel slots per week. Figures 5-6 As shown.

[0042] Through indoor tests, the mechanically slotted screen tube has an average external extrusion strength of 22 MPa, an average roughness of 1.17 μm, an average tensile strength of over 800 MPa, and the average hardness of the base tube is basically the same as that of the slotted surface, indicating that it was not affected by heat treatment.

[0043] Field test of high-strength slotted screen pipe in horizontal wells achieved a 100% success rate, with zero pump inspections and an average daily fluid production of 52.34 m³. 3 / d,a average daily oil production 16.14m 3 / d.

[0044] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A cold-worked round cutter mechanical slot screen characterized by, The high-strength mechanical slotted screen pipe for horizontal well is composed of a base pipe (1), a supporting rib (2) and a supporting ring (3), and a slotted outer pipe (4) is sleeved on the base pipe (1), the base pipe (1) is connected with the slotted outer pipe (4) through the supporting rib (2) and the supporting ring (3), the supporting rib (2) is welded on the base pipe (1) through the slotted outer pipe (4), and the supporting ring (3) is welded on the base pipe (1) and connected with the slotted outer pipe (4).

2. The cold finished round mill mechanical slot screen of claim 1 wherein, The base pipe (1) is made of P110H material.

3. The cold finished round mill mechanical slot screen of claim 1 wherein, The base pipe (1) is provided with spiral holes.

4. The cold finished round mill mechanical slot screen of claim 3 wherein, The supporting rib (2) is welded on the base pipe (1), and each spiral is spot-welded at least three times to ensure that the supporting rib (2) has no gap with the base pipe (1).

5. The cold finished round mill mechanical slot screen of claim 1 wherein, The slotted outer pipe (4) is made of 316L steel material.

6. The cold finished round mill mechanical slot screen of claim 1 wherein, The slotted outer pipe (4) is cut by mechanical cutting.

7. The cold finished round mill mechanical slot screen of claim 1 wherein, The slotted outer pipe (4) is cut in parallel.

8. The cold finished round mill mechanical slot screen of claim 6 wherein, The average hardness of the base pipe (1) is basically the same as the average hardness of the slotted surface of the slotted outer pipe (4).

9. The cold finished round mill mechanical slot screen of claim 1 wherein, The supporting ring (3) is welded on the base pipe (1), the upper end of the supporting ring (3) is connected with the slotted outer pipe (4), and the slotted outer pipe (4) is supported and fixed.

10. The cold finished round mill mechanical slot screen of claim 9, wherein, The base pipe (1) is connected with the next base pipe through the upper end of the supporting ring (3).

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