Centralizer forming die

Abstract

The invention relates to the field of centralizer molds, in particular to a centralizer forming mold which comprises an inner mold and a plurality of outer molds distributed annularly, the outer molds wrap the inner mold to form an annular cavity with a spiral contour, the inner mold is provided with a vertical pouring gate and a tangential pouring gate, molten steel flows in the circumferential direction to wash impurities, and the impurities are discharged through a top riser; the outer die seam is located on the outer surface of the protruding part, and flash cleaning is convenient. The cooling system is composed of a first cooling pipe of the inner mold and a second cooling pipe of the outer mold, the first cooling pipe and the second cooling pipe extend along the convex part thread line, circulating cooling liquid is introduced, rapid heat dissipation of the thick-wall convex part is achieved, and shrinkage cavities are reduced through synchronous solidification. The top of the outer mold is provided with a confluence channel, the bottom of the outer mold is provided with a shunting channel, and flange connection is matched to realize cooling liquid circulation and optimize temperature uniformity. The problems that a traditional mold is difficult to demold, cooling is uneven, and impurities are left are solved, and the casting quality and production efficiency of the centralizer are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of centralizer molds, and particularly to a centralizer forming mold. Background Art

[0002] A centralizer is a key component in oil drilling operations, mainly used to stabilize the drill string, maintain the wellbore trajectory, and reduce the friction and wear between the drill tool and the wellbore wall. Its core function is to ensure that the drill string is always in the center position of the wellbore during the drilling process through mechanical support, thereby avoiding problems such as wellbore collapse and bit eccentric wear caused by drill string eccentricity, and improving drilling efficiency and safety at the same time.

[0003] Structurally, a centralizer is usually an annular component, composed of an internal installation cylinder and external helical protrusions and recesses distributed circumferentially. The installation cylinder is used to connect with the drill string, and the helical contour design of the protrusions and recesses can effectively guide the cuttings to be discharged, reduce the risk of sticking the drill, and provide uniform support through contact with the wellbore wall.

[0004] The manufacturing process of large centralizers is mainly casting. However, due to the special structure of the centralizer, problems such as difficult demolding, complex assembly of split molds, and difficult removal of surface flash often occur. These problems seriously affect production efficiency and increase the difficulty of subsequent processing.

[0005] In addition, due to the large transition of the wall thickness of the centralizer, casting defects are likely to occur during the pouring process due to untimely feeding, affecting the overall quality of the product. Summary of the Invention

[0006] In order to solve the foregoing technical problems, the present invention provides a centralizer forming mold, which solves the problems of low production efficiency and easy occurrence of casting defects through the design of a split mold and a local cooling system, and is specifically achieved through the following technical solutions: A centralizer forming mold of the present invention includes an inner mold and a plurality of outer molds surrounding and covering the outer surface of the inner mold, and an annular cavity of the centralizer is formed between the inner mold and the outer molds; The inner mold includes an inner cylinder and an outer cylinder coaxially fixed to the outer surface of the inner cylinder. A vertical sprue is provided inside the inner cylinder, a pouring cup is provided at the top, and the annular cavity is communicated with the bottom through a plurality of tangentially arranged gates; The outer mold includes a mold wall, a top wall is provided at the top of the mold wall, and a bottom wall is provided at the bottom. The top wall and the bottom wall are respectively in sealing lap with the outer cylinder; A cooling system includes a plurality of first cooling pipes arranged in the outer cylinder and a plurality of second cooling pipes arranged outside the mold wall. The contours of the first cooling pipes and the second cooling pipes extend along the thread direction and are aligned with the inner and outer sides of the protrusions of the centralizer; The cooling system further includes a shunt channel and a confluence channel. The shunt channel is respectively communicated with the bottoms of the first cooling pipe and the second cooling pipe, and coolant is input through a supply pipe. The confluence channel is respectively communicated with the tops of the first cooling pipe and the second cooling pipe, and the coolant is discharged through a return pipe.

[0007] Preferably, the top of the first cooling pipe buried inside the outer cylinder is communicated with the confluence channel through a first joint, and the bottom of the first cooling pipe is communicated with the shunt channel through a second joint to realize the circulating flow of the coolant.

[0008] Preferably, a plurality of risers are fixedly arranged on the upper surface of the top wall. The risers are communicated with the top of the annular cavity and are directly opposite to the top of the convex part of the centralizer.

[0009] Preferably, flange plates are arranged on the outer sides of the ends of the shunt channel and the confluence channel, and the adjacent outer molds are hermetically butted through fasteners.

[0010] Preferably, the lead thread pitch and the rotation direction of the lead thread of the first cooling pipe are the same as those of the lead thread of the convex part profile.

[0011] Preferably, the shunt channel is butted with the second joint through a fourth joint, and the confluence channel is butted with the first joint through a third joint.

[0012] Preferably, the gate is arranged tangentially along the outer surface of the outer cylinder, so that the molten steel flows circumferentially after entering the annular cavity.

[0013] Preferably, the thread pitch and the rotation direction of the thread line track of the second cooling pipe are the same as those of the thread line track of the convex part.

[0014] Preferably, the axes of the shunt channel and the confluence channel coincide with the axis of the inner cylinder.

[0015] After adopting the above technical solutions, the beneficial effects of the present invention are as follows: 1. A plurality of outer molds distributed in a ring shape cover the inner mold to form a centralizer cavity. The outer mold joints are located on the outer surface of the convex part, and the flash is easy to remove. At the same time, the split outer mold design simplifies the mold assembly and disassembly process, and significantly reduces the operation complexity.

[0016] 2. The first and second cooling pipes extending along the thread line are respectively arranged on the inner mold and the outer mold, and are aligned with the convex part position. The convex part is quickly cooled by circulating coolant, promoting synchronous solidification of the thick-wall area and the thin-wall area, and effectively avoiding defects such as shrinkage cavities and porosity.

[0017] 3. The tangentially arranged gate enables the molten steel to flow circumferentially in the cavity, flushing impurities to float to the riser for discharge, reducing the risk of slag inclusion; the riser is directly opposite the top of the convex part to store molten steel for feeding, further reducing the probability of shrinkage cavities.

[0018] 4. Adopting the coolant flow mode from bottom to top, combined with the arc design of the confluence and diversion channels, realizes synchronous and uniform cooling of the inner and outer molds, ensures that the temperature gradient of the casting is controllable, and reduces the risks of deformation and cracking. Brief Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0020] Figure 1 It is a three-dimensional installation view of the centralizer forming die; Figure 2 It is a partial disassembled schematic view of the centralizer forming die; Figure 3 It is a structural schematic view of the centralizer; Figure 4 It is a structural schematic view of the inner mold and the outer mold; Figure 5 It is a partial cross-sectional view of the inner mold; Figure 6 It is a three-dimensional view of the outer mold from the first perspective; Figure 7 It is a three-dimensional view of the outer mold from the second perspective.

[0021] 100 - Centralizer, 101 - Installation cylinder, 102 - Convex part, 103 - Concave part; 200 - Inner mold, 201 - Inner cylinder, 202 - Sprue cup, 203 - Outer cylinder, 204 - First cooling pipe, 205 - First joint, 206 - Second joint, 207 - Installation disc, 208 - Gate; 300 - Outer mold, 301 - Mold wall, 302 - Top wall, 303 - Riser, 304 - Confluence channel, 305 - Third joint, 306 - Return pipe, 307 - Bottom wall, 308 - Second cooling pipe, 309 - Diversion channel, 310 - Supply pipe, 311 - Fourth joint. Detailed Embodiment

[0022] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without some of these specific details. The following description of the embodiments is only provided to provide a better understanding of the present invention by showing examples of the present invention.

[0023] The orientation terms appearing in the following description are all the directions shown in the drawings and do not limit the specific structure of the present invention. In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, the terms "installation, 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 directly connected or indirectly connected. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] An embodiment of the present invention provides a centralizer forming mold. Refer to Figures 1 to 4 , the centralizer forming mold includes an inner mold 200 and a plurality of outer molds 300. The plurality of outer molds 300 surround and cover the outer surface of the inner mold 200 to ensure that the inner mold 200 and the outer molds 300 surround and form an annular cavity of the centralizer 100 structure.

[0025] As Figure 3 shown, the centralizer 100 includes an installation cylinder 101 provided inside and a plurality of convex portions 102 uniformly and circumferentially fixed on the outer surface of the installation cylinder 101. There are concave portions 103 between the respective convex portions 102, and the contours of the convex portions 102 and the concave portions 103 extend along the direction of the thread line. Due to the spaced distribution of the convex portions 102 and the concave portions 103, the splicing positions of the plurality of outer molds 300 are located at.

[0026] The above structure of the centralizer 100 causes the wall thickness of the centralizer 100 to fluctuate at intervals along the circumferential direction. This structure makes it easy to appear casting defects during the casting process of the blank of the centralizer 100, and due to the spiral contour structure of the convex portions 102 and the concave portions 103, the assembly and demolding of the mold are difficult during the casting process of the centralizer 100.

[0027] Therefore, by arranging the plurality of outer molds 300 in a ring shape, on the one hand, it is convenient for the assembly and disassembly of the inner mold 200 and the outer molds 300, and on the other hand, the flash formed at the joints of the plurality of outer molds 300 is concentrated on the outer surface of the convex portions 102, which is convenient for the removal of the flash and the machining of the centralizer 100.

[0028] And a splicing gap is formed on the outer surface of the convex portion 102, which is beneficial to heat dissipation at the position of the convex portion 102. Since the convex portion 102 is the position with the thickest wall thickness in the centralizer 100, rapid cooling of the convex portion 102 facilitates the complete molding of the centralizer 100 and avoids casting defects such as shrinkage cavities and porosity.

[0029] As a further explanation of the above embodiment, see Figure 4 、 Figure 5 , the inner mold 200 includes an inner cylinder 201. A vertical runner is coaxially provided inside the inner cylinder 201. A pouring cup 202 is fixedly installed at the top of the inner cylinder 201, which is convenient for pouring molten steel into the vertical runner through the pouring cup 202 during the pouring process.

[0030] An outer cylinder 203 is coaxially fixed to the outer surface of the inner cylinder 201. A plurality of first cooling pipes 204 are buried inside the outer cylinder 203. The contour of the first cooling pipes 204 extends along the direction of the thread. The guiding thread of the contour of the first cooling pipes 204 has the same pitch and rotation direction as the guiding thread of the contour of the convex portion 102. The first cooling pipes 204 are aligned with the convex portion 102 inside and outside to achieve rapid cooling at the position of the convex portion 102.

[0031] The top of the first cooling pipe 204 is fixedly connected to a first joint 205, and the bottom of the first cooling pipe 204 is fixedly connected to a second joint 206. The second joint 206 is used to introduce the coolant into the first cooling pipe 204, and the first joint 205 is used to discharge the coolant in the first cooling pipe 204, realizing the circulating flow of the coolant inside the first cooling pipe 204, thereby completing the continuous cooling of the position of the convex portion 102.

[0032] A mounting disk 207 is coaxially fixed to the bottom of the outer surface of the outer cylinder 203, which is used to mount a plurality of outer molds 300 and seal and align them with the plurality of outer molds 300.

[0033] The bottom of the vertical runner inside the inner cylinder 201 is communicated with the outer surface of the outer cylinder 203 through a plurality of gates 208. The plurality of gates 208 penetrate the side walls of the inner cylinder 201 and the outer cylinder 203. The gates 208 are arranged tangentially to the outer surface of the outer cylinder 203. This structure enables the molten steel to enter the cavity formed by the inner mold 200 and the plurality of outer molds 300 from the vertical runner through the gates 208, and the molten steel entering the cavity flows circumferentially around the axis of the outer cylinder 203 inside the cavity.

[0034] On the one hand, the above pouring method is convenient for removing and flushing the residual impurities in the cavity by the molten steel, making the impurities concentrate on the surface of the molten steel and float, avoiding defects such as slag inclusion and sand inclusion in the casting. On the other hand, through the flow of the molten steel in the cavity, the temperature uniformity of the casting along the circumferential position can be ensured, avoiding defects such as gradual deformation and cracking caused by local overheating or overcooling.

[0035] As a further explanation of the above embodiments, see Figure 4 , Figure 6 , Figure 7 The outer mold 300 includes a mold wall 301, a top wall 302 is fixedly installed on the top of the mold wall 301, the inner circumferential surface of the top wall 302 is sealed and overlapped with the outer surface of the outer cylinder 203, and a plurality of risers 303 are fixedly provided on the upper surface of the top wall 302, the risers 303 pass through the top wall 302 and are connected with the top of the cavity, and a plurality of risers 303 are directly opposite to the top of the convex portion 102.

[0036] The above structural design is conducive to discharging the residue and sand particles floating with the molten steel to the outside through the riser 303, thereby ensuring the quality of the casting. At the same time, the extra molten steel stored in the risers 303 can be used to compensate for the shrinkage of the convex portion 102 when it is cooled, thereby avoiding the formation of shrinkage holes inside the convex portion 102 and affecting the product quality.

[0037] The outer side of the upper surface of the top wall 302 is fixed to the confluence channel 304, and a plurality of third joints 305 are fixedly installed on the inner side of the confluence channel 304. The third joints 305 are connected to the inside of the confluence channel 304, and the third joints 305 are connected to the first joints 205 by docking. A return pipe 306 is fixedly installed on the outer side of the confluence channel 304 for discharging the coolant in the confluence channel 304 to the outside.

[0038] Among them, the contour shape of the converging channel 304 is arc-shaped, and the axis of its contour shape coincides with the axis of the inner cylinder 201. This structure ensures that after several outer molds 300 are installed and spliced, the converging channels 304 at the top are just connected end to end, thereby facilitating the circulation and transportation of the coolant.

[0039] Among them, a flange is provided on the outer side of the end of the converging channel 304, so that the operator can complete the sealing connection and installation of several converging channels 304 by fasteners such as bolts.

[0040] The inner side of the bottom of the mold wall 301 is fixed to the bottom wall 307 , the inner circumferential surface of the bottom wall 307 is sealed and overlapped with the outer surface of the outer cylinder 203 , and the lower surface of the bottom wall 307 is sealed and overlapped with the upper surface of the mounting plate 207 .

[0041] The outer side of the bottom of the mold wall 301 is fixed to the diversion channel 309, and a plurality of fourth joints 311 are fixedly installed on the inner side of the diversion channel 309. The fourth joints 311 are connected to the interior of the bottom wall 307, and the fourth joints 311 are connected to the second joint 206 by docking. A flow supply pipe 310 is fixedly installed on the outer side of the diversion channel 309 for replenishing and transporting cooling liquid into the diversion channel 309.

[0042] A number of second cooling pipes 308 are fixedly installed on the outer surface of the mold wall 301. The top of the second cooling pipe 308 is communicated with the confluence channel 304, and the bottom of the second cooling pipe 308 is communicated with the shunt channel 309. This structure enables the coolant inside the shunt channel 309 to be transported to the confluence channel 304 through a number of second cooling pipes 308, thereby realizing the cooling of the outside of the installation cylinder 101 by the second cooling pipes 308.

[0043] Among them, the contour of the second cooling pipe 308 extends along the trajectory of the thread, and the pitch and rotation direction of the thread trajectory are the same as those of the thread trajectory of the convex part 102.

[0044] Among them, the contour shape of the shunt channel 309 is arc-shaped, and the axis of its contour shape coincides with the axis of the inner cylinder 201. After a number of outer molds 300 are installed and spliced together, the shunt channels 309 at their bottoms are just connected end to end, which is convenient for the circulating transportation of the coolant.

[0045] Among them, a flange is provided on the outer side of the end of the shunt channel 309, which is convenient for the operator to complete the sealing butt joint and installation of a number of shunt channels 309 through fasteners such as bolts.

[0046] The working principle of the present invention is as follows: When a number of outer molds 300 located on the outside are installed and butted annularly around the inner mold 200 to form the cavity of the aligner 100, the operator pours molten steel downward through the pouring cup 202 into the vertical pouring channel inside the inner cylinder 201. When the molten steel reaches the bottom of the inner cylinder 201, it flows into the bottom of the cavity through a number of tangentially arranged gates 208 and flows annularly inside the cavity and gradually fills the inside of the cavity.

[0047] In the above process, the molten steel flushes the impurities and sand grains in the cavity, making them float to the upper surface of the molten steel. As the molten steel level rises, they are finally discharged outward through a number of risers 303 provided at the top.

[0048] When the operator starts to pour molten steel into the cavity, the coolant is started to be injected into the shunt channel 309 through the supply pipe 310. A part of the coolant in the shunt channel 309 enters a number of first cooling pipes 204 through the fourth joint 311 and the second joint 206 to realize the cooling inside the aligner 100. The coolant in the first cooling pipe 204 flows back into the confluence channel 304 through the first joint 205 and the third joint 305 and is discharged outward through the return pipe 306.

[0049] The coolant in another part of the flow diversion channel 309 enters the interior of a plurality of second cooling pipes 308 disposed outside the mold wall 301 from the bottom, is transmitted upward along the interior of the second cooling pipes 308 to the tops of the second cooling pipes 308, enters the confluence channel 304, and is finally discharged outward through a return pipe 306 disposed outside the confluence channel 304.

[0050] Through the circulation of the coolant inside and outside the cavity, synchronous cooling of the inside and outside of the cavity is achieved, and the cooling points are mainly concentrated in the region of the convex part 102 with a relatively thick wall thickness, enabling this part to dissipate heat quickly, thereby achieving synchronous solidification with the concave part 103 region with a relatively thin wall thickness and reducing casting defects such as shrinkage cavities and porosity.

[0051] The present invention adopts a coolant flow mode from bottom to top, thereby ensuring that the temperature inside the cavity gradually increases from bottom to top, facilitating the feeding of the molten steel at the top after the solidification of the molten steel at the bottom of the cavity and reducing the risk of casting defects.

[0052] In accordance with the embodiments of the present invention as described above, these embodiments do not describe all the details in detail, nor do they limit the invention to only the specific embodiments. Obviously, many modifications and variations can be made according to the above description. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and its modified use based on the present invention. Any modification, equivalent replacement, improvement, etc., made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A centralizer forming die, characterized in that, Comprising: An inner mold (200) and several outer molds (300) surrounding and covering the outer surface of the inner mold (200), an annular cavity of a centralizer (100) being formed between the inner mold (200) and the outer molds (300); The inner mold (200) includes an inner cylinder (201) and an outer cylinder (203) coaxially fixed to the outer surface of the inner cylinder (201). A vertical sprue is provided inside the inner cylinder (201), a pouring cup (202) is provided at the top, and the bottom is communicated with the annular cavity through several tangentially arranged gates (208); The outer mold (300) includes a mold wall (301), a top wall (302) is provided at the top of the mold wall (301), and a bottom wall (307) is provided at the bottom. The top wall (302) and the bottom wall (307) are respectively in sealing overlap with the outer cylinder (203); A cooling system, including several first cooling pipes (204) arranged inside the outer cylinder (203) and several second cooling pipes (308) arranged outside the mold wall (301). The profiles of the first cooling pipes (204) and the second cooling pipes (308) both extend along the thread direction and are aligned inside and outside with the convex portions (102) of the centralizer (100); The cooling system further includes a shunt channel (309) and a confluence channel (304). The shunt channel (309) is respectively communicated with the bottoms of the first cooling pipes (204) and the second cooling pipes (308), and coolant is input through a supply pipe (310). The confluence channel (304) is respectively communicated with the tops of the first cooling pipes (204) and the second cooling pipes (308), and the coolant is discharged through a return pipe (306).

2. The centralizer forming die according to claim 1, characterized in that, The top of the first cooling pipe (204) buried inside the outer cylinder (203) is communicated with the confluence channel (304) through a first joint (205), and the bottom of the first cooling pipe (204) is communicated with the shunt channel (309) through a second joint (206) to realize the circulating flow of the coolant.

3. The centralizer forming die according to claim 1, wherein Several risers (303) are fixedly provided on the upper surface of the top wall (302). The risers (303) are communicated with the top of the annular cavity and are directly opposite to the tops of the convex portions (102) of the centralizer (100).

4. The aligner forming die according to claim 1, characterized in that, Flange plates are provided on the outer sides of the ends of the shunt channel (309) and the confluence channel (304), and the adjacent outer molds (300) are sealed and docked through fasteners.

5. The aligner forming die according to claim 1, wherein The lead thread pitch and rotation direction of the guiding thread of the first cooling pipe (204) are the same as those of the profile of the convex portion (102).

6. The centralizer forming die according to claim 2, wherein, The shunt channel (309) is docked with the second joint (206) through a fourth joint (311), and the confluence channel (304) is docked with the first joint (205) through a third joint (305).

7. The centering device forming die according to claim 1, wherein, The gates (208) are arranged tangentially along the outer surface of the outer cylinder (203) so that the molten steel flows circumferentially after entering the annular cavity.

8. The aligner forming die according to claim 1, wherein, The thread pitch and rotation direction of the thread track of the second cooling pipe (308) are the same as those of the thread track of the convex portion (102).

9. The centralizer forming die according to claim 1, characterized in that, The axes of the shunt channel (309) and the confluence channel (304) both coincide with the axis of the inner cylinder (201).

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