Scalable vacuum piping structure for electron beam cold hearth furnace

Abstract

Provided is a telescopic vacuum pipe structure for an electron beam cold hearth furnace, comprising an outer pipe and an inner pipe, the right end of the outer pipe and the left end of the inner pipe are each provided with a flange for detachable fixed connection with an adjacent pipe, the inner pipe is a stepped pipe with an outer diameter at the left end larger than an outer diameter at the right end, the left end of the outer pipe is provided with a shock-resistant sealing connection assembly, the right end of the inner pipe is inserted into the inner part of the outer pipe through the shock-resistant sealing connection assembly, and the outer pipe and the inner pipe are sealingly connected by the shock-resistant sealing connection assembly. The telescopic vacuum pipe structure is optimized, the shock-resistant sealing connection assembly is used to sealingly connect the outer pipe and the inner pipe inserted into the outer pipe at one end, the problems of small telescopic compensation, easy leakage and short service life of the existing metal corrugated pipe connection structure are solved, and the sealing reliability, deformation resistance and service life of the vacuum pipe are improved.

Description

Technical Field

[0001] This utility model belongs to the field of electron beam cold hearth furnace technology, specifically relating to a retractable vacuum pipe structure for electron beam cold hearth furnaces. Background Technology

[0002] As a core component of high-vacuum equipment (such as electron beam cold hearth furnaces), the sealing performance of vacuum pipes directly determines the stability and safety of the system operation. Vacuum pipes often require prefabrication and precision machining, and length control is a critical indicator during installation. During installation, deviations in infrastructure and cumulative machining errors can cause deviations in pipe length. Excessive or insufficient deviations will compromise the fit accuracy of the joint surfaces: excessive length can lead to deformation of the interface under stress, creating tiny gaps; insufficient length will prevent effective sealing. Both can cause vacuum leakage, directly affecting the equipment's processing quality and operational safety.

[0003] Currently, the industry typically uses corrugated metal pipes as the connection structure for vacuum pipelines. These pipes are formed by rolling and welding thin steel plates. While they can meet basic connection requirements, they have significant technical limitations. From a process perspective, the thin steel plate material itself lacks rigidity, making it difficult to uniformly control the weld strength during the rolling and welding process. Furthermore, the corrugated structure design results in minimal expansion and contraction compensation. Under operating conditions such as temperature fluctuations and slight vibrations, this limited expansion and contraction capacity cannot offset deformation stress, easily leading to weld cracking or pipe wall damage, and consequently, leakage. Simultaneously, the thin steel plate has weak fatigue resistance; long-term, repeated small deformations accelerate material aging, resulting in a generally shorter service life for corrugated metal pipes, increasing equipment maintenance costs and downtime risks. Therefore, improvements are necessary to address these issues. Utility Model Content

[0004] The technical problem solved by this utility model is to provide a retractable vacuum pipe structure for an electron beam cold hearth furnace. By optimizing the vacuum pipe structure and using an anti-vibration sealing connection component to retractably and adjustably seal the outer pipe and the inner pipe inserted into the outer pipe at one end, the existing metal bellows connection structure is found to have small expansion compensation, easy leakage, and short service life. This improves the sealing reliability, deformation resistance and service life of the vacuum pipe.

[0005] The technical solution adopted in this utility model is: a retractable vacuum pipe structure for an electron beam cold hearth furnace, including an outer pipe and an inner pipe. The right end of the outer pipe and the left end of the inner pipe are provided with flanges for detachable connection with adjacent pipes. The inner pipe is a stepped pipe with a left end outer diameter larger than the right end outer diameter. The left end of the outer pipe is provided with a shock-resistant sealing connection assembly, and the right end of the inner pipe passes through the shock-resistant sealing connection assembly and is inserted into the outer pipe. The outer pipe and the inner pipe, which has been adjusted to the correct position, are sealed and connected by the shock-resistant sealing connection assembly.

[0006] The seismic-resistant sealing connection assembly includes a fixed flange, a connecting flange, and a sealing ring. The connecting flange has an annular plate structure, and the right end of the central hole of the connecting flange has a 45° chamfer. The fixed flange is concentrically fixed to the left end of the outer pipe, and the hole wall of the fixed flange and the hole wall of the connecting flange located at the left end of the fixed flange are both reserved with the outer wall of the small diameter section of the inner pipe for the inner pipe to adjust its position. The sealing ring is adapted to fit into the annular groove formed by the chamfer of the connecting flange and the left end face of the fixed flange. When the fixed flange and the connecting flange are connected and locked by multiple fastening bolts, the sealing ring deforms and presses against the outer wall of the small diameter section of the inner pipe to achieve a seal.

[0007] Furthermore, the chamfer of the connecting flange and the left end face of the fixed flange form a triangular annular groove, and the sealing ring with a circular cross-section is adapted to the annular groove. When the fastening bolts are tightened, the connecting flange squeezes the sealing ring to deform it and press it against the outer wall of the small diameter section of the inner pipe.

[0008] Furthermore, with the multiple fastening bolts loosened, the seismic-resistant sealing connection assembly can move arbitrarily within the small-diameter section of the inner pipe, enabling the expansion and contraction adjustment of the entire pipe length.

[0009] Furthermore, the sealing ring is a standard silicone rubber O-ring.

[0010] Furthermore, the fixed flange has multiple through holes evenly distributed around its circumference, and the connecting flange has multiple threaded holes evenly distributed around its circumference that are adapted to the through holes. The fastening bolts pass through the through holes on the fixed flange and are adapted to connect with the threaded holes on the connecting flange.

[0011] Advantages of this utility model compared to the prior art: 1. In this technical solution, the inner and outer pipes are separated by a pre-reserved gap to allow the inner pipe to expand and contract smoothly along the length of the outer pipe, which increases the amount of expansion and contraction compensation and makes the expansion and contraction adjustment flexible. This meets the equipment's need to offset deformation stress through a large range of expansion and contraction under operating conditions such as temperature fluctuations and slight vibrations, and eliminates the leakage problem caused by pipeline damage due to insufficient expansion and contraction compensation. 2. The triangular cross-section sealing ring of this technical solution undergoes uniform deformation under the extrusion of the connecting flange, and fits tightly against the outer wall of the inner pipe, improving the sealing stability and reliability; at the same time, it enables the seismic-resistant sealing connection assembly to buffer the impact of equipment vibration and meet seismic requirements. 4. This technical solution uses a vacuum pipeline formed by sealing the inner and outer pipes with flanges fixed at the outer ends, which have a wall thickness greater than that of traditional corrugated pipes. This improves the fatigue resistance of the vacuum pipeline, allowing it to be used repeatedly for a long time under conditions requiring expansion and contraction, thus extending its service life. The sealing ring is easy to replace, effectively reducing equipment maintenance costs and downtime risks. The flange structure enables detachable connection with adjacent pipes, and the fastening bolt connection method facilitates installation, commissioning, and subsequent maintenance, improving equipment operation and maintenance efficiency and making disassembly and assembly convenient. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 for Figure 1 A magnified view of a portion of point A in the middle. Detailed Implementation

[0013] The following will refer to the embodiments of this utility model. Figure 1-2 The technical solutions in the embodiments of this utility model are clearly and completely described herein. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0014] It should be noted that, unless otherwise stated herein, the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0015] In this document, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0016] Electron beam cold hearth furnaces use retractable vacuum pipe structures, such as... Figure 1-2As shown, the system includes an outer tube 1 and an inner tube 2. Both the right end of the outer tube 1 and the left end of the inner tube 2 are equipped with flanges 3 for detachable connection to adjacent pipes. The inner tube 2 is a stepped tube with a left-end outer diameter larger than the right-end outer diameter. The outer circumferential wall of the small-diameter section at the right end of the inner tube 2 is a lathe-machined surface, and the length of the small-diameter section of the inner tube 2 is the telescopic adjustment length of the vacuum pipeline. The left end of the outer tube 1 is equipped with a shock-resistant sealing connection assembly, and the right end of the inner tube 2 passes through this assembly and is inserted into the outer tube 1. The shock-resistant sealing connection assembly then seals the outer tube 1 and the inner tube 2, which is in position, together. This structure optimizes the vacuum pipeline structure by using a shock-resistant sealing connection assembly to provide a telescopically adjustable seal between the outer tube 1 and the inner tube 2, which is inserted into the outer tube 1 at one end. This solves the problems of small telescopic compensation, easy leakage, and short service life in existing metal corrugated pipe connection structures, thereby improving the sealing reliability, deformation resistance, and service life of the vacuum pipeline.

[0017] The earthquake-resistant sealing connection assembly is as follows: The earthquake-resistant sealing connection assembly includes a fixed flange 4, a connecting flange 5, and a sealing ring 6. The connecting flange 5 has an annular plate structure, and the right end of the center hole of the connecting flange 5 has a 45° chamfer. The fixed flange 4 is concentrically fixed to the left end of the outer pipe 1. Both the hole wall of the fixed flange 4 and the hole wall of the connecting flange 5 located at the left end of the fixed flange 4 have pre-reserved gaps with the outer wall of the small-diameter section of the inner pipe 2 for the expansion and contraction adjustment of the inner pipe 2. The sealing ring 6 is adapted to the chamfer of the connecting flange 5 and the left end face shape of the fixed flange 4. When the fixed flange 4 and the connecting flange 5 are connected and locked in the annular groove by multiple fastening bolts 7, the sealing ring 6 deforms and presses against the outer wall of the small diameter section of the inner pipe 2 to achieve a seal; in the above structure, the inner pipe 2 and the outer pipe 1 are separated by a reserved gap to allow the inner pipe 2 to move smoothly along the length of the outer pipe 1, which increases the amount of expansion and contraction compensation and makes the expansion and contraction adjustment flexible; it meets the needs of the equipment to offset the deformation stress by a large range of expansion and contraction under operating conditions such as temperature fluctuations and slight vibrations, and eliminates the leakage problem caused by pipeline damage due to small expansion and contraction compensation. In this design, the chamfered corner of the connecting flange 5 and the left end face of the fixed flange 4 form a triangular annular groove. A sealing ring 6 with a circular cross-section fits into this groove. When the fastening bolts 7 are tightened, the connecting flange 5 compresses the sealing ring 6, causing it to deform and press against the outer wall of the small-diameter section of the inner pipe 2. Specifically, with the multiple fastening bolts 7 loosened, the seismic-resistant sealing connection assembly can move arbitrarily within the small-diameter section of the inner pipe 2, allowing for expansion and contraction adjustment of the entire pipe length. Specifically, the sealing ring 6 is a standard silicone rubber O-ring, which is low-cost and easy to procure. In this structure, the circular cross-section sealing ring 6 undergoes uniform deformation under the pressure of the connecting flange 5, tightly fitting against the outer wall of the inner pipe 2, improving sealing stability and reliability. Simultaneously, the seismic-resistant sealing connection assembly can buffer the impact of equipment vibration, meeting seismic requirements. The detachable fixing structure of the fixed flange 4 and the connecting flange 5 is as follows: the fixed flange 4 has multiple through holes evenly distributed around its circumference, and the connecting flange 5 has multiple threaded holes evenly distributed around its circumference that are adapted to the through holes. The fastening bolt 7 passes through the through holes on the fixed flange 4 and is adapted to connect with the threaded holes on the connecting flange 5.

[0018] The outer tube 1 is formed by welding a pipe section with a flange 3 at one end to a seamless steel pipe, and the welding position is far away from the flange 3, thereby avoiding the impact of welding on the processing accuracy.

[0019] This technical solution uses a vacuum pipeline formed by sealing the inner pipe 2 and the outer pipe 1 with a flange 3 fixed at the outer end, which has a wall thickness greater than that of a traditional corrugated pipe. This improves the fatigue resistance of the vacuum pipeline, allowing it to be used repeatedly for a long time under conditions requiring expansion and contraction, thus extending its service life. The sealing ring 6 is easy to replace, effectively reducing equipment maintenance costs and downtime risks. The flange structure enables detachable connection with adjacent pipelines, and the fastening bolts 7 facilitate installation, commissioning, and subsequent maintenance, improving equipment operation and maintenance efficiency and making disassembly and assembly convenient.

[0020] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0021] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A retractable vacuum pipe structure for an electron beam cold hearth furnace, characterized in that: It includes an outer pipe (1) and an inner pipe (2). The right end of the outer pipe (1) and the left end of the inner pipe (2) are provided with flanges (3) for detachable connection with adjacent pipes. The inner pipe (2) is a stepped pipe with a left outer diameter larger than the right outer diameter. The left end of the outer pipe (1) is provided with a seismic-resistant sealing connection assembly. The right end of the inner pipe (2) passes through the seismic-resistant sealing connection assembly and is inserted into the outer pipe (1). The seismic-resistant sealing connection assembly seals the outer pipe (1) and the inner pipe (2) which has been adjusted to the correct position.

2. The retractable vacuum pipe structure for an electron beam cold hearth furnace according to claim 1, characterized in that: The seismic-resistant sealing connection assembly includes a fixed flange (4), a connecting flange (5), and a sealing ring (6). The connecting flange (5) has an annular plate structure, and the right end of the center hole of the connecting flange (5) has a 45° chamfer. The fixed flange (4) is concentrically fixed to the left end of the outer tube (1), and the hole wall of the fixed flange (4) and the hole wall of the connecting flange (5) located at the left end of the fixed flange (4) are both reserved with the outer wall of the small diameter section of the inner tube (2) for the expansion and contraction adjustment of the inner tube (2). The sealing ring (6) is adapted to the annular groove formed by the chamfer of the connecting flange (5) and the left end face of the fixed flange (4). When the fixed flange (4) and the connecting flange (5) are connected and locked by multiple fastening bolts (7), the sealing ring (6) deforms and presses against the outer wall of the small diameter section of the inner tube (2) to achieve sealing.

3. The retractable vacuum pipe structure for an electron beam cold hearth furnace according to claim 2, characterized in that: The chamfer of the connecting flange (5) and the left end face of the fixing flange (4) form a triangular annular groove. The sealing ring (6) with a circular cross-section is fitted into the annular groove. When the fastening bolt (7) is tightened, the connecting flange (5) squeezes the sealing ring (6) to deform it and press it against the outer wall of the small diameter section of the inner tube (2).

4. The retractable vacuum pipe structure for an electron beam cold hearth furnace according to claim 3, characterized in that: With the multiple fastening bolts (7) loosened, the anti-vibration sealing connection assembly can move arbitrarily in the small diameter section of the inner pipe (2), thereby realizing the expansion and contraction adjustment of the entire pipe length.

5. The retractable vacuum pipe structure for an electron beam cold hearth furnace according to any one of claims 2-4, characterized in that: The sealing ring (6) is a standard silicone rubber O-ring.

6. The retractable vacuum pipe structure for an electron beam cold hearth furnace according to claim 2, characterized in that: The fixed flange (4) has multiple through holes evenly distributed around its circumference, and the connecting flange (5) has multiple threaded holes evenly distributed around its circumference that are adapted to the through holes. The fastening bolt (7) passes through the through holes on the fixed flange (4) and is adapted to connect with the threaded holes on the connecting flange (5).

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