Valve bimetallic composite flange and method of manufacturing same

Abstract

The present application relates to a valve bimetallic composite flange and its manufacturing method, belonging to the valve casting technical field, characterized by: including the outer shell and the filling body; the outer shell adopts the steel plate stamping to form the disc-shaped shell; the disc-shaped shell has the center through hole connected with the outer cylindrical surface of the valve body channel, and the outer shell is provided with the pouring opening communicating with its inner cavity; the filling body is formed by pouring the molten iron into the inner cavity of the outer shell through the pouring opening and solidifying, and the valve body channel and the outer shell are fused and solidified to be connected as an integral structure. The product adopts the outer shell formed by the pressure casting of the precious metal alloy material and the filling body formed by pouring the molten iron into the inner cavity of the outer shell, and the bimetallic composite structure is composed, which solves the problems of environmental pollution and material loss existing in the present lost wax and sand casting process, the manufacturing process has less environmental pollution and low material loss; and under the condition of ensuring the product performance, the amount of precious metal material is greatly reduced. It has the advantages of environmental protection in production process, low product cost and the like.

Description

Technical Field

[0001] This invention belongs to the field of valve technology, and particularly relates to a bimetallic composite flange for valves and its manufacturing method. Background Technology

[0002] Flanges are key components of valves, typically welded to the inlet and outlet channels of the valve body for installation on pipelines. Currently, common flange manufacturing methods include lost-wax casting and sand casting. Molten steel is poured into a wax or sand mold, and after cooling and solidification, the wax and sand molds are melted and crushed to produce the flange blank. The main disadvantages of these methods are: lost-wax casting and sand casting result in significant material loss from wax and sand molds, leading to high production costs; furthermore, the discharge of wax and sand molds causes substantial environmental pollution; additionally, the entire product is cast from molten steel, resulting in high material costs. This is especially true for valves used in special media conditions, requiring corrosion resistance, high-temperature resistance, and oxidation resistance. Flanges in these applications require high-performance materials such as nickel-chromium alloys, which are very expensive, particularly for large-diameter flanges. Summary of the Invention

[0003] This invention addresses the shortcomings of existing technologies by providing a new production process that enables the product to possess the performance characteristics of high-performance materials while reducing material costs. Furthermore, the production process is environmentally friendly, with no material loss or environmental pollution, resulting in a low-cost and environmentally friendly product.

[0004] The technical solution for realizing the present invention is as follows: A bimetallic composite flange for a valve, characterized in that it comprises an outer shell and a filler; the outer shell is formed by stamping a steel plate into a disc-shaped shell, the disc-shaped shell having a central through hole that is interconnected with the outer cylindrical surface of the valve body channel, the central through hole being interconnected with the inner cavity of the outer shell, and a plurality of axial cylindrical holes being uniformly arranged along the circumferential direction in the outer shell plane outside the central through hole, the axial cylindrical holes being sealed and isolated from the inner cavity of the outer shell, and the outer shell having a casting port communicating with its inner cavity; the filler is formed by injecting molten iron into the inner cavity of the outer shell through the casting port and solidifying it, in the state where the outer shell and the valve body channel are connected, the molten iron injected into the cavity of the outer shell melts and solidifies the two together.

[0005] The preferred embodiment is that the disc-shaped shell is integrally formed by die-casting an upper disc, a lower cylinder, and a hollow cylinder. The two ends of the hollow cylinder are die-cast between the bottom surfaces of the upper disc and the lower cylinder, and its inner hole forms an axial cylindrical hole for sealing and isolating the inner cavity of the outer shell.

[0006] A preferred embodiment is that a plurality of axial positioning strips extending upward toward the disk are uniformly provided on the bottom surface of the lower cylinder along the circumferential direction of the central through hole, and the axial positioning strips have an inclination angle toward the center line of the central through hole.

[0007] A method for manufacturing a bimetallic composite flange for a valve, characterized by including a shell stamping process and a filler casting process; The outer casing stamping process includes: S1 installs the special stamping dies for the upper disc, lower cylinder, and hollow cylinder onto the press; S2 steel plates are placed in special stamping dies for the upper disc, lower cylinder, and hollow cylinder respectively. The press is turned on to stamp and form the upper disc, lower cylinder, and hollow cylinder. S3 places the upper disc, lower cylinder, and hollow cylinder into a special mold, and turns on the press to press the three together to form an outer shell. S4 outer shell demolding, burr removal, inspection and warehousing; The filling material casting process includes: S1 The outer shell is fitted onto the outer cylindrical surface of the valve body channel through the central through hole. The valve body channel is inserted from the bottom surface of the lower cylinder to the middle position of the central through hole. The outer shell is elastically clamped and installed on the outer cylindrical surface of the valve body channel by the axial positioning bar. A plug is set at the upper end of the valve body channel. The central through hole above the plug forms a casting port that communicates with the inner cavity. The S2 casting mechanism injects molten iron into the inner cavity of the outer shell through the casting port; After the S3 molten iron is poured into the casting port, the casting mechanism is removed, and the upper surface of the outer shell is pressed in until it is flush with the upper end surface of the valve body channel. After the S4 molten iron solidifies, precious metal alloy material is welded onto the gap between the upper plane of the outer shell and the outer cylindrical surface of the valve body channel. S5 is used for machining the weld overlay.

[0008] A preferred embodiment is to incorporate a shell heating process between process steps S1 and S2 of the filler casting process, heating the shell to a temperature range of 200°C to 300°C.

[0009] The advantages of this invention compared to existing technologies are as follows: the flange uses a bimetallic composite structure consisting of a shell formed by die casting of precious metal alloy materials and a filler formed by casting molten iron into the inner cavity of the shell. This solves the problems of environmental pollution and material loss in existing lost-wax and sand casting processes, resulting in a manufacturing process with less environmental pollution and lower material loss. Furthermore, it significantly reduces the amount of precious metal materials used while ensuring product performance. It offers advantages such as environmentally friendly production processes and low product costs. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the outer shell of the present invention.

[0011] Figure 2 This is the present invention. Figure 1 Top view.

[0012] Figure 3 This is the present invention. Figure 2 Cross-sectional view of the structure along the AA direction.

[0013] Figure 4 This is a structural schematic diagram of the connection state between the outer shell and the valve body channel of the present invention.

[0014] In the diagram: 1 Outer shell, 2 Central through hole, 3 Axial cylindrical hole, 4 Inner cavity, 5 Axial positioning strip, 6 Filler, 7 Valve body channel. Detailed Implementation

[0015] like Figure 1 , Figure 2 , Figure 3 , Figure 4 The illustrated bimetallic composite flange for valves is characterized by comprising an outer shell 1 and a filler 6. The outer shell 1 is formed into a disc shape by stamping steel plate. The disc shape has a central through hole 2 that is interconnected with the outer cylindrical surface of the valve body channel 7. The steel plate material is selected and determined according to the operating conditions of the medium used in the product to meet the performance requirements of the operating conditions of the medium. The central through hole 2 is interconnected with the inner cavity 4 of the outer shell 1, that is, the inner cavity 4 and the central through hole 2 are interconnected to form an integral cavity. A plurality of axial cylindrical holes 3 are evenly arranged along the circumferential direction in the plane of the outer shell 1 outside the central through hole 2. The axial cylindrical holes 3 are flange mounting holes. The axial cylindrical holes 3 are sealed and isolated from the inner cavity 4 of the outer shell 1 to prevent molten iron from leaking into the axial cylindrical holes 3 during casting. The outer shell 1 is provided with a casting port that connects to its inner cavity 4. The filler 6 is formed by molten iron being injected into the inner cavity 4 of the outer shell 1 through the casting port and solidifying. When the valve body channel 7 and the outer shell 1 are connected, the molten iron injected into the inner cavity 4 melts and solidifies the two into one.

[0016] The technical effect of this solution is that molten iron is injected into the outer shell 1 and solidified to form a filler 6. The outer shell 1 is made of a high-performance alloy material selected according to the properties of the medium being used, which meets the performance requirements of the medium such as corrosion resistance, wear resistance, and high temperature resistance. The filler 6 is made of low-value iron material, which provides the rigidity and strength requirements of the product, reduces the consumption of precious metal materials, and significantly reduces the product cost.

[0017] The outer shell 1 is composed of an upper disc, a lower cylinder, and a hollow cylinder, which are die-cast as a whole. The upper disc is placed at the upper end of the lower cylinder, and the two are die-cast and riveted together by a press. The two ends of the hollow cylinder are die-cast between the bottom surfaces of the upper disc and the lower cylinder, and its inner hole forms an axial cylindrical hole 3 that is sealed and isolated from the inner cavity 4 of the outer shell 1.

[0018] The technical effect of this feature is that it facilitates the stamping and die-casting manufacturing of the outer casing 1.

[0019] A plurality of axial positioning strips 5 extending upwards are evenly provided on the bottom surface of the lower cylindrical shell 1 along the circumferential direction of the central through hole 2. The axial positioning strips 5 have an inclination angle that is inclined toward the center of the central through hole 2, so that the inner plane of each axial positioning strip 5 forms a conical surface, which facilitates the positioning connection between the shell 1 and the valve body channel 7.

[0020] The technical effect of this feature is that by utilizing the elasticity of the axial positioning bar 5, the outer shell 1 is clamped and positioned on the valve body channel 7, so that the outer shell 1 can be displaced axially along the valve body channel 7 under the action of external force. This facilitates the adjustment of the axial position between the outer shell 1 and the valve body channel 7, making positioning convenient and eliminating the need for a special positioning device to position the outer shell 1 on the outer cylindrical surface of the valve body channel 7.

[0021] A method for manufacturing a bimetallic composite flange for a valve, characterized by including a shell stamping process and a filler casting process; The outer casing stamping process includes: S1 installs the special stamping dies for the upper disc, lower cylinder, and hollow cylinder onto the press respectively; S2 places steel plates into special stamping dies for an upper disc, a lower cylinder, and a hollow cylinder, respectively, and turns on the press to stamp them into an upper disc, a lower cylinder, and a hollow cylinder, respectively. S3 places the upper disc, lower cylinder, and hollow cylinder in a special mold, and turns on the press to press the three together to form an outer shell. In this process step, the lower cylinder is first placed in a special mold that has been installed on the press, the upper disc is placed at the open end of the lower cylinder, and the two ends of the hollow cylinder are pressed between the lower cylinder and the upper disc, so that the inner hole of the hollow cylinder is aligned with the circular hole in the plane of the upper disc and the lower cylinder. The press is then turned on to punch and rivet the connection of the three together. S4 outer shell 1 demolding, burr removal, inspection and warehousing; The filling material casting process includes: S1 The outer shell 1 is fitted onto the outer cylindrical surface of the valve body channel 7 through the central through hole 2. The valve body channel 7 is inserted from the bottom surface of the lower cylinder of the outer shell 1 to the middle position of the central through hole 2. The outer shell 1 is elastically clamped and positioned on the outer cylindrical surface of the valve body channel 7 by the axial positioning bar 5. A plug with a movable fit with its inner hole is provided at the upper end of the valve body channel 7 to seal and isolate the inner hole of the valve body channel 7 from the central through hole 2. The central through hole 2 above the plug forms a casting port that communicates with the inner cavity 4, allowing molten iron to flow into the inner cavity 4 quickly from the casting port. The upper surface of the plug has an upwardly convex conical surface. During casting, molten iron flows into the inner cavity 4 along the periphery of the conical surface, accelerating the flow speed of molten iron. The S2 casting mechanism injects molten iron into the inner cavity 4 of the outer shell 1 through the casting port; when the inner cavity 4 is filled with molten iron, the external force pushes the upper end face of the valve body channel 7 to align with the upper disc plane of the outer shell 1. When the valve body channel 7 is pressed into the central through hole 2, it pushes the plug and the molten iron in the casting port out of the central through hole 2, and at the same time squeezes the molten iron in the inner cavity 4 to increase the density of the filler 6. S3 removes the plug and molten iron that comes out of the center through hole 2; After the S4 molten iron solidifies, precious metal alloy material is welded into the weld overlay groove formed between the outer cylindrical surface of the valve body channel 7 and the chamfer of the inner hole of the upper disk of the outer shell 1. S5 is used for machining the weld overlay.

[0022] The technical advantages of this solution are: molten iron is injected into the cavity formed between the outer shell 1 and the valve body channel 7 and solidifies into a flange, which is then cast into an integral structure with the valve body channel 7. This results in low production costs and an environmentally friendly process. In the casting process, the valve body channel 7 is pressed into the central through hole 2 of the outer shell 1 to seal the casting port, thus avoiding the need for a casting port treatment process. This simplifies the casting process steps.

[0023] A heating process for the outer shell 1 is set between the S1 and S2 process steps of the filler casting process. The outer shell 1 is heated to a temperature range of 200℃ to 300℃ to improve the fluidity of molten iron in the inner cavity 4 of the outer shell 1 during casting.

[0024] The structure and manufacturing method of the bimetallic composite flange of the present invention can also be used on pipelines. When used on pipelines, simply fit the outer shell 1 onto the outer cylindrical surface of the pipeline, and then cast it according to the above-mentioned filling casting process to fuse the outer shell 1, the filling 6 and the pipeline together.

[0025] The casting gate of the present invention can also be set on the inner or outer circular surface of the two sides of the outer shell 1. After casting is completed, the casting gate needs to be processed, and the processing of the casting gate is more difficult. The time for molten iron to fill the inner cavity 4 of the outer shell 1 is also longer.

Claims

1. A bimetallic composite flange for valves, characterized in that: It includes an outer shell (1) and a filler (6); the outer shell (1) is formed by stamping steel plate into a disc-shaped shell, the disc-shaped shell has a central through hole (2) that is connected to the outer cylindrical surface of the valve body channel (7), the central through hole (2) is connected to the inner cavity (4) of the outer shell (1), and a number of axial cylindrical holes (3) are uniformly arranged in the circumferential direction in the plane of the outer shell (1) outside the central through hole (2), and the axial cylindrical holes (3) are sealed and isolated from the inner cavity (4) of the outer shell (1); the outer shell (1) is provided with a casting port that connects to its inner cavity (4); the filler (6) is formed by injecting molten iron into the inner cavity (4) of the outer shell (1) through the casting port and solidifying it. After the valve body channel (7) and the outer shell (1) are connected together, molten iron is injected into the inner cavity (4) to melt and solidify the two into an integral structure.

2. The valve bimetallic composite flange according to claim 1, characterized in that: The outer shell (1) is composed of an upper disc, a lower cylinder and a hollow cylinder die-cast as a whole. The upper disc is placed at the upper end of the lower cylinder and the two are pressed and riveted together by a press. The two ends of the hollow cylinder are die-cast between the bottom surfaces of the upper disc and the lower cylinder, and its inner hole forms an axial cylindrical hole (3) that is sealed and isolated from the inner cavity (4) of the outer shell (1).

3. The valve bimetallic composite flange according to claim 2, characterized in that: A plurality of axial positioning strips (5) extending upward in the direction of the central through hole (2) are uniformly provided on the bottom surface of the lower cylinder of the outer shell (1). The axial positioning strips (5) have an inclination angle towards the center of the central through hole (2).

4. A method for manufacturing a valve bimetallic composite flange as described in claim 3, characterized in that: This includes the outer shell stamping process and the filler casting process; The outer casing stamping process includes: S1 installs the special stamping dies for the upper disc, lower cylinder, and hollow cylinder onto the press respectively; S2 places steel plates into special stamping dies for an upper disc, a lower cylinder, and a hollow cylinder, respectively, and turns on the press to stamp them into an upper disc, a lower cylinder, and a hollow cylinder, respectively. S3 places the upper disc, lower cylinder, and hollow cylinder into a special mold, and turns on the press to press the three together to form an outer shell (1). S4 outer shell (1) Demolding, deburring, inspection and warehousing; The filling material casting process includes: S1 The outer shell (1) is fitted onto the outer cylindrical surface of the valve body channel (7) through the central through hole (2). The valve body channel (7) is inserted from the bottom surface of the lower cylinder of the outer shell (1) into the middle position of the central through hole (2). The axial positioning bar (5) elastically clamps and positions the outer shell (1) on the outer cylindrical surface of the valve body channel (7). A plug with a movable fit with its inner hole is provided at the upper end of the valve body channel (7). The plug seals and isolates the inner hole of the valve body channel (7) from the central through hole (2). The central through hole (2) above the plug forms a casting port that communicates with the inner cavity (4). The upper surface of the plug has an upwardly protruding conical surface. The S2 casting mechanism injects molten iron into the inner cavity (4) of the outer shell (1) through the casting port; when the inner cavity (4) is filled with molten iron, it is pushed by external force to align the upper end face of the valve body channel (7) with the upper disc plane of the outer shell (1), and the valve body channel (7) is pressed into the central through hole (2), pushing the plug and the molten iron in the casting port out from the central through hole (2); S3 removes the plug and molten iron ejected from the central through hole (2); After the S4 molten iron solidifies, precious metal alloy material is welded into the weld overlay groove formed between the outer cylindrical surface of the valve body channel (7) and the inner hole of the upper disk of the outer shell (1). S5 is used for machining the weld overlay.

5. The manufacturing method of the valve bimetallic composite flange according to claim 4, characterized in that: in Between the S1 and S2 process steps of the filler casting process, a heating process for the outer shell (1) is set, with the heating temperature of the outer shell (1) ranging from 200℃ to 300℃.

Images