A lifting device for molybdenum rod heat treatment

Abstract

The application discloses a kind of molybdenum rod heat treatment lifting appliance, which relates to the technical field of heat treatment process equipment of refractory metal (molybdenum and molybdenum alloy). The lifting appliance includes a cover plate that can be detachably installed on the furnace opening of a pit furnace and covers and seals the furnace opening. The cover plate is provided with a plurality of rotating rods that are arranged in a vertical direction and penetrate the cover plate. The lower ends of the rotating rods are detachably connected to a plurality of rotating rods and are synchronously rotated with the rotating rods. The cover plate is provided with a driving mechanism at the upper portion thereof, which is in driving connection with the plurality of rotating rods and is used to drive the rotating rods and the lifting rod to rotate. The cover plate is uniformly distributed with a plurality of support rods on the outer side thereof, which are in cooperation with the base on the outer side of the furnace opening of the pit furnace. The upper portion of the support rod is provided with a lifting lug for the overhead traveling crane to lift the cover plate. The molybdenum rod is continuously self-rotated by the driving mechanism, which realizes uniform heating in the circumferential direction and optimization of grain structure, and effectively prevents bending deformation caused by high-temperature creep.

Description

Technical Field

[0001] This application relates to the technical field of heat treatment equipment for refractory metals (molybdenum and molybdenum alloys), specifically a lifting tool for heat treatment of molybdenum rods. Background Technology

[0002] Molybdenum rods are widely used in metallurgy, aerospace, electronics, and nuclear industries due to their high melting point, high strength, and excellent high-temperature performance. Heat treatment is a key process for improving the internal structure of molybdenum rods, eliminating internal stress, and enhancing their overall mechanical properties. It is usually carried out in a pit furnace under high-temperature hydrogen atmosphere or vacuum conditions.

[0003] Currently, the commonly known heat treatment of molybdenum rods mostly uses a beam-type lifting device. Its basic structure involves a rigid beam directly spanning above the furnace opening of a pit furnace. Multiple lifting rods suspend the molybdenum rods from the lower part of the beam. Subsequently, an independent furnace cover, separate from the furnace opening, is fastened from the upper part of the beam to seal the furnace chamber. However, this beam-type lifting device has the following shortcomings in practical use:

[0004] 1. During the heat treatment of molybdenum rods, there is an unavoidable temperature difference between the "sun-facing side" (direct heating element) and the "shaded side" of the molybdenum rods, which leads to uneven heating in the circumferential direction of the molybdenum rods. This, in turn, causes asynchronous recrystallization, uneven grain size, and even thermal stress, affecting the consistency of material performance and service life.

[0005] 2. Under prolonged exposure to high temperatures, molybdenum rods are prone to creep due to their own weight, leading to bending deformation, making it difficult to guarantee the straightness of the product and resulting in a low yield.

[0006] 3. The lifting beam is actually located directly outside the furnace chamber and under the furnace cover of the pit furnace, rather than inside the furnace. The lifting beam is completely exposed to the high-temperature heat flow that continuously escapes from the furnace opening. Although the temperature in the furnace opening area is slightly lower than that in the center of the furnace chamber, in actual use, it will not only cause creep to the metal structure of the lifting beam, but also make it inconvenient for subsequent secondary lifting operations.

[0007] Therefore, there is an urgent need in this field for a special heat treatment lifting tool that can ensure uniform heating of molybdenum rods, effectively prevent deformation, and have excellent heat insulation and sealing performance. Summary of the Invention

[0008] To overcome the shortcomings of the prior art, this utility model discloses a lifting device for heat treatment of molybdenum rods. This utility model drives the molybdenum rod to rotate continuously through a driving mechanism, thereby achieving uniform heating in the circumferential direction and optimizing the grain structure, effectively preventing bending deformation caused by high-temperature creep.

[0009] To achieve the above objectives, this application provides the following technical solution:

[0010] A lifting device for heat treatment of molybdenum rods, comprising:

[0011] The cover plate is detachable and can be installed at the furnace opening of the pit furnace to cover and seal the furnace opening;

[0012] Multiple rotating rods are used to rotate vertically to seal the through-cover plate.

[0013] Multiple booms are detachably connected to the lower ends of multiple rotating rods and rotate synchronously with the rotating rods. The lower ends of the booms are used to suspend the molybdenum rods.

[0014] The drive mechanism is fixedly installed on the upper part of the cover plate and is connected to multiple rotating rods for driving the rotating rods and the lifting rods to rotate, so as to achieve uniform heating of the molybdenum rod;

[0015] Multiple support rods are evenly distributed along the circumference of the cover plate on the outside of the cover plate, and cooperate with the base on the outside of the well furnace opening to support the cover plate.

[0016] Multiple lifting lugs are located on the upper part of multiple support rods and are used for overhead cranes to lift and transport cover plates.

[0017] Furthermore, the cover plate includes, from top to bottom, the following:

[0018] The carbon steel cold-faced layer forms the upper structural support of the cover plate;

[0019] A ceramic fiber insulation layer is fixed to the lower part of the carbon steel cold surface layer to prevent heat from being transferred upwards from the furnace.

[0020] A heat-resistant alloy protective layer is fixed to the lower part of the ceramic fiber insulation layer, forming the lower hot surface of the cover plate. Furthermore, the heat-resistant alloy protective layer has an inverted conical structure, with multiple support rods connected to the upper part of the heat-resistant alloy protective layer of the cover plate.

[0021] Furthermore, the sidewall of the heat-resistant alloy protective layer is provided with an annular groove arranged along its circumference, and a sealing ring is provided in the annular groove to form an interference fit soft seal with the inner wall of the furnace opening.

[0022] Furthermore, the drive mechanism includes:

[0023] Multiple transmission gears are fixedly installed on the upper ends of multiple rotating rods, and the multiple transmission gears mesh with each other;

[0024] The drive motor is fixedly mounted on the upper part of the cover plate, and its output end is connected to any transmission gear.

[0025] Furthermore, the upper part of the cover plate is provided with a mounting seat located above any of the transmission gears, and the drive motor is located on the upper part of the mounting seat.

[0026] Furthermore, the rotating rod rotates through the cover plate via a bearing assembly, which includes a bearing housing embedded in the cover plate and a bearing disposed within the bearing housing. The rotating rod is fixed to the inner ring of the bearing.

[0027] Furthermore, a heat-insulating coupling is coaxially fixedly connected to the lower end of the rotating rod, and the hanging rod can be detachably installed at the lower end of the heat-insulating coupling.

[0028] Furthermore, the suspension rod includes a lifting ring and a threaded rod located at the lower part of the lifting ring, and the lower end of the thermally insulating coupling is provided with a hook for suspending the lifting ring.

[0029] Furthermore, the inner surface of the hook is provided with a notch for accommodating the lifting ring.

[0030] Compared with the prior art, the beneficial effects of this application are:

[0031] The drive mechanism drives the meshing transmission gears to make all rotating rods and hanging rods rotate synchronously and smoothly, thereby driving the suspended molybdenum rod to rotate around its axis. This completely eliminates the temperature difference between the "sun-facing side" and the "shaded side" of the molybdenum rod caused by heating on one side in the furnace, ensuring the absolute uniformity of the temperature field of the molybdenum rod in the circumferential direction, and providing a fundamental guarantee for obtaining a uniform recrystallized structure and excellent material properties.

[0032] The continuous and slow rotation of the molybdenum rod ensures that the influence of its own gravity on high-temperature creep is evenly distributed throughout the circumference, avoiding the directional bending deformation caused by the continuous action of gravity in a single direction when suspended at rest, and significantly improving the straightness and yield of the heat-treated product.

[0033] The cover plate adopts a three-layer composite structure of "carbon steel cold surface layer - ceramic fiber insulation layer - heat-resistant alloy protective layer", and combined with the interference soft seal formed by the inverted conical protective layer and the flexible sealing ring, together forming an efficient thermal barrier and airtight barrier, which greatly blocks the upward transfer of heat in the furnace, protects the upper drive mechanism, and ensures the stability of the protective atmosphere in the furnace to prevent workpiece oxidation.

[0034] This invention uses a drive mechanism to continuously rotate the molybdenum rod, achieving uniform heating in the circumferential direction and optimizing grain structure, effectively preventing bending deformation caused by high-temperature creep. At the same time, a multi-layer composite cover plate assembly physically isolates the drive mechanism from the high-temperature furnace chamber, and combined with an inverted conical sealing structure, it achieves efficient heat insulation and sealing of the furnace opening, protecting the transmission system and stabilizing the furnace atmosphere. Ultimately, while improving the consistency of molybdenum rod heat treatment quality and yield, it significantly improves the reliability and service life of the equipment. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of this utility model;

[0036] Figure 2 This is a schematic diagram of the cover plate structure of this utility model;

[0037] Figure 3 This is a schematic diagram of the rotating rod assembly structure of this utility model.

[0038] In the diagram: 1. Cover plate; 1.1. Carbon steel cold-faced layer; 1.2. Ceramic fiber insulation layer; 1.3. Heat-resistant alloy protective layer; 1.3.1. Annular groove; 1.4. Sealing ring; 2. Drive motor; 2.1. Mounting base; 2.2. Conductive head; 3. Transmission gear; 4. Support rod; 5. Lifting lug; 6. Lifting rod; 6.1. Lifting ring; 6.2. Threaded rod; 7. Rotating rod; 7.1. Lifting hook; 7.1.1. Notch; 7.2. Thermal insulation coupling; 7.3. Bearing seat; 7.4. Bearing. Detailed Implementation

[0039] The technical solution of this utility model will be described below with reference to the accompanying drawings of the embodiments of this utility model. In the description, it should be understood that if there are terms such as "upper", "lower", "front", "rear", "left", "right" indicating the orientation or positional relationship, they are only corresponding to the drawings of this utility model for the convenience of describing this utility model, and do not indicate or imply that the device or element referred to must have a specific orientation.

[0040] Please refer to the instruction manual appendix. Figure 1-3 This utility model provides a technical solution:

[0041] Example 1: A lifting device for heat treatment of molybdenum rods includes a cover plate 1 that can be detachably installed at the furnace mouth of a pit furnace and covers and seals the furnace mouth. Specifically, the cover plate 1 has a plurality of support rods 4 evenly distributed along its circumference on its outer side. The support rods 4 have lifting lugs 5 on their upper parts. The overhead crane lifts the cover plate 1 through the lifting lugs 5. When the cover plate 1 is lifted to the furnace mouth of the pit furnace, the support rods 4 are supported by the base on the outer side of the furnace mouth, so that the cover plate 1 is fastened to the furnace mouth.

[0042] The cover plate 1 is provided with multiple rotating rods 7 arranged vertically and rotating through the cover plate 1. Specifically, the rotating rods 7 rotate through the cover plate 1 via bearing assemblies. The bearing assembly includes a bearing seat 7.3 embedded in the cover plate 1 and a bearing 7.4 disposed in the bearing seat 7.3. The rotating rods 7 are fixed to the inner ring of the bearing 7.4. The lower end of the rotating rods 7 is provided with a suspension rod 6 that rotates synchronously with the rotating rods 7 and is used to suspend the molybdenum rod. The upper part of the cover plate 1 is provided with a drive mechanism that is connected to the multiple rotating rods 7 and drives the rotating rods 7 and the suspension rod 6 to rotate, so as to achieve uniform heating of the molybdenum rod. The drive mechanism includes multiple transmission gears 3 and a drive motor 2. The multiple transmission gears 3 are respectively fixedly installed on the upper ends of the multiple rotating rods 7 and mesh with each other. For example, the multiple rotating rods 7 can be distributed in a matrix or in a ring. Adjacent transmission gears 3 mesh with each other. The upper part of the cover plate 1 is provided with a mounting base 2.1 located on the upper part of any transmission gear 3. The drive motor 2 is located on the upper part of the mounting base 2.1, and its output end is connected to any transmission gear 3. In order to power the drive motor 2, the upper end of the drive motor 2 is provided with a conductive head 2.2 electrically connected to the drive motor 2. The inner surface of the well furnace cover is provided with a power supply head that corresponds to and matches the conductive head 2.2. After the well furnace cover is fastened, the power supply head is connected to the conductive head 2.2 to power the drive motor 2. Alternatively, a sliding contact line power supply system can be used, which supplies power through the contact between the brush at the upper end of the drive motor 2 and the sliding contact line on the inner surface of the furnace cover. Alternatively, a high-temperature resistant wireless power supply module can be used, which supplies power based on the principle of electromagnetic induction through the transmitter fixedly installed on the outside of the furnace cover and the receiver installed on the drive motor 2.

[0043] During the heat treatment of molybdenum rods, the molybdenum rods are vertically suspended from the lower end of the suspension rod 6. After the cover plate 1 is hoisted and fastened to the furnace opening by an overhead crane, the molybdenum rods are inserted into the furnace. The cover plate 1 can provide heat insulation and sealing for the furnace opening. The drive motor 2 is started, and multiple transmission gears 3 are driven to rotate synchronously, thereby driving the rotating rod 7, the suspension rod 6, and the molybdenum rod to rotate synchronously. This not only prevents the temperature difference between the sun-facing side of the molybdenum rod facing the heating element and the shaded side facing away from the heating element, allowing the molybdenum rod to face the heat source evenly and eliminating the temperature gradient in the circumferential direction, but also effectively prevents the molybdenum rod from bending and deforming, avoiding plastic deformation of the molybdenum rod.

[0044] In Example 2, in order to enable the cover plate 1 to effectively seal and insulate the furnace opening of the pit furnace and provide strong protection for the safe and stable operation of the drive mechanism, the cover plate 1 is composed of a carbon steel cold surface layer 1.1, a ceramic fiber heat insulation layer 1.2, and a heat-resistant alloy protective layer 1.3 from top to bottom. The carbon steel cold surface layer 1.1 forms the upper structural support of the cover plate 1. The ceramic fiber heat insulation layer 1.2 is fixed to the lower part of the carbon steel cold surface layer 1.1 to prevent the upward transfer of heat in the furnace. The heat-resistant alloy protective layer 1.3 is fixed to the lower part of the ceramic fiber heat insulation layer 1.2 to form the lower hot surface of the cover plate 1.

[0045] In order to ensure that the sealing cover 1 can be effectively fastened inside the pit furnace opening, the heat-resistant alloy protective layer 1.3 has an inverted conical structure. Multiple support rods 4 are connected to the upper part of the heat-resistant alloy protective layer 1.3 of the cover plate 1. In order to ensure that the heat-resistant alloy protective layer 1.3 is effectively sealed to the pit furnace opening, the side wall of the heat-resistant alloy protective layer 1.3 is provided with an annular groove 1.3.1 arranged along its circumference. The annular groove 1.3.1 is provided with a sealing ring 1.4 that forms an interference fit soft seal with the inner wall of the furnace opening. The sealing ring 1.4 is made of ceramic fiber rope or graphite material.

[0046] To further improve the heat insulation and sealing performance of the cover plate 1, a heat insulation coupling 7.2 is coaxially fixedly connected to the lower end of the rotating rod 7. The heat insulation coupling 7.2 is embedded and rotatably installed on the lower surface of the cover plate 1, and the hanger 6 is installed at the lower end of the heat insulation coupling 7.2.

[0047] In embodiment three, in order to achieve vertical suspension of the suspension rod 6 and the molybdenum rod, the suspension rod 6 includes a lifting ring 6.1 and a threaded rod 6.2 located at the lower part of the lifting ring 6.1. The threaded rod 6.2 is threadedly connected to the threaded hole on the upper end face of the molybdenum rod.

[0048] To connect the boom 6 to the thermally insulating coupling 7.2, the lower end of the thermally insulating coupling 7.2 is provided with a hook 7.1 for suspending the lifting ring 6.1. To ensure the vertical and stable suspension of the boom 6 and the molybdenum rod, the inner surface of the hook 7.1 is provided with a notch 7.1.1 for accommodating the lifting ring 6.1. The notch 7.1.1 can be used to limit and lock the lifting ring 6.1, thereby preventing the lifting ring 6.1 from sliding inside the hook 7.1 during the rotation of the molybdenum rod.

[0049] The parts of this utility model not described in detail are prior art. It is obvious to those skilled in the art that this utility model is not limited to the details of the above exemplary embodiments, and that this utility model can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the above embodiments should be regarded as exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description. Therefore, it is intended to include all changes that fall within the meaning and scope of the equivalents of the claims in this utility model, and no reference numerals in the claims should be regarded as limiting the content of the claims.

Claims

1. A lifting tool for heat treatment of molybdenum rods, characterized in that, include: The cover plate (1) can be detachably installed at the furnace opening of the pit furnace and used to cover and seal the furnace opening; Multiple rotating rods (7) are used to rotate vertically to seal the through cover plate (1); Multiple rods (6) are detachably connected to the lower ends of multiple rotating rods (7) and rotate synchronously with the rotating rods (7). The lower ends of the rods (6) are used to suspend the molybdenum rods. The drive mechanism is fixedly installed on the upper part of the cover plate (1) and is connected to multiple rotating rods (7) for driving the rotating rods (7) and the hanging rod (6) to rotate so as to achieve uniform heating of the molybdenum rod; Multiple support rods (4) are evenly distributed around the cover plate (1) on the outside of the cover plate (1) and cooperate with the base on the outside of the well furnace opening to support the cover plate (1). Multiple lifting lugs (5) are respectively located on the upper part of multiple support rods (4) for the overhead crane to lift the cover plate (1).

2. The lifting fixture for heat treatment of molybdenum rods according to claim 1, characterized in that: The cover plate (1) includes, from top to bottom: The carbon steel cold-faced layer (1.1) forms the upper structural support of the cover plate (1); A ceramic fiber insulation layer (1.2) is fixed to the lower part of the carbon steel cold surface layer (1.1) to prevent heat from being transferred upwards inside the furnace; A heat-resistant alloy protective layer (1.3) is fixed to the lower part of the ceramic fiber insulation layer (1.2) to form the lower hot surface of the cover plate (1).

3. The lifting fixture for heat treatment of molybdenum rods according to claim 2, characterized in that: The heat-resistant alloy protective layer (1.3) has an inverted conical structure, and multiple support rods (4) are connected to the upper part of the heat-resistant alloy protective layer (1.3) of the cover plate (1).

4. A lifting tool for heat treatment of molybdenum rods according to claim 3, characterized in that: The sidewall of the heat-resistant alloy protective layer (1.3) is provided with an annular groove (1.3.1) arranged along its circumference, and a sealing ring (1.4) is provided in the annular groove (1.3.1) to form an interference fit soft seal with the inner wall of the furnace opening.

5. A lifting tool for heat treatment of molybdenum rods according to claim 1, characterized in that: The drive mechanism includes: Multiple transmission gears (3) are fixedly installed on the upper ends of multiple rotating rods (7), and the multiple transmission gears (3) mesh with each other; The drive motor (2) is fixedly installed on the upper part of the cover plate (1), and its output end is driven by any transmission gear (3).

6. A lifting tool for heat treatment of molybdenum rods according to claim 5, characterized in that: The cover plate (1) is provided with a mounting seat (2.1) located on the upper part of any transmission gear (3), and the drive motor (2) is located on the upper part of the mounting seat (2.1).

7. A lifting tool for heat treatment of molybdenum rods according to claim 1, characterized in that: The rotating rod (7) rotates through the cover plate (1) via the bearing assembly. The bearing assembly includes a bearing seat (7.3) embedded in the cover plate (1) and a bearing (7.4) disposed in the bearing seat (7.3). The rotating rod (7) is fixed to the inner ring of the bearing (7.4).

8. A lifting fixture for heat treatment of molybdenum rods according to claim 7, characterized in that: The lower end of the rotating rod (7) is coaxially fixedly connected to a heat-insulating coupling (7.2), and the hanging rod (6) can be detachably installed at the lower end of the heat-insulating coupling (7.2).

9. A lifting tool for heat treatment of molybdenum rods according to claim 8, characterized in that: The suspension rod (6) includes a lifting ring (6.1) and a threaded rod (6.2) located at the lower part of the lifting ring (6.1). The lower end of the thermally insulating coupling (7.2) is provided with a hook (7.1) for suspending the lifting ring (6.1).

10. A lifting tool for heat treatment of molybdenum rods according to claim 9, characterized in that: The inner surface of the hook (7.1) is provided with a notch (7.1.1) for accommodating the lifting ring (6.1).

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