A piercing pin for an aluminum alloy seamless pipe extrusion machine

Abstract

The utility model relates to metal extrusion processing equipment technical field, specifically disclose a kind of aluminium alloy seamless pipe extruder's piercing needle, including needle body, the needle body is by rear section needle body, intermediate stress buffer ring and front section replaceable wear head three parts are connected in series by fastener and constitute, the both ends end surface of intermediate stress buffer ring is respectively provided with first concave spherical surface and second concave spherical surface, the front end of rear section needle body is equipped with the first convex spherical surface matched with first concave spherical surface, effectively relieve stress concentration at connecting place by three-section spherical surface connecting structure, greatly improve fatigue resistance and reliability, significantly reduce maintenance cost using replaceable wear head, spherical surface cooperation has self-centering effect and guarantees centring accuracy, high-temperature sealing structure prevents metal invasion and ensures long-term use stability, overall structure gives consideration to high performance and low cost, especially suitable for high-temperature high-pressure aluminium alloy extrusion piercing working condition.

Description

Technical Field

[0001] This utility model relates to the field of metal extrusion processing equipment technology, and specifically discloses a piercing needle for an aluminum alloy seamless tube extrusion press. Background Technology

[0002] Seamless aluminum alloy tubing is a type of material with a hollow cross-section and no seams, available in round, square, or rectangular shapes. It is made by piercing steel ingots or solid tubes to form a rough tube, followed by hot rolling, cold rolling, or cold drawing. During piercing, the piercing needle is in direct contact with the high-temperature copper ingot, subjected to extreme temperatures, pressures, and rapid heating and cooling, resulting in extremely harsh working conditions. Existing piercing needles are made of alloy steel, which suffers from reduced strength and stiffness at high temperatures, often leading to instability during piercing and a shorter service life due to the high temperatures. Since high-temperature resistant materials are more expensive than alloy steel, using only high-temperature resistant materials to manufacture piercing needles would result in high production costs.

[0003] Chinese Patent (Patent No.: CN202621610U, disclosing a piercing needle for an aluminum alloy seamless tube extrusion press) describes a piercing needle for such an press. The needle body includes a heat-resistant piercing tube and a mounting and fixing tube connecting the heat-resistant piercing tube. The heat-resistant piercing tube is a molybdenum-based alloy tube or a nickel-based alloy tube, and the mounting and fixing tube is an alloy steel tube. Compared with existing technologies, this invention's needle body is divided into two sections: a mounting and fixing tube and a heat-resistant piercing tube. The heat-resistant piercing tube is only used in the area in contact with the high-temperature copper ingot, which saves costs, withstands high temperatures and pressures, and extends the product's service life.

[0004] However, while the aforementioned perforation needles reduce costs, two main problems remain: 1. The heat-resistant perforation section and the mounting and fixing section are usually rigidly connected (e.g., threaded). Under frequent thermal cycling and high pressure, stress concentration easily occurs at the connection, leading to fatigue cracks or fractures. 2. After the heat-resistant section wears or is damaged, the entire section or the entire needle body needs to be replaced, and maintenance costs can still be optimized. Utility Model Content

[0005] This invention proposes a piercing needle for an aluminum alloy seamless tube extrusion press. The three-section spherical connection structure effectively alleviates stress concentration at the connection point, significantly improving fatigue resistance and reliability.

[0006] This utility model is implemented as follows: a piercing needle for an aluminum alloy seamless tube extrusion machine includes a needle body, which is composed of a rear needle body, an intermediate stress buffer ring, and a front replaceable wear-resistant head connected in series by fasteners. The two end faces of the intermediate stress buffer ring are respectively provided with a first concave spherical surface and a second concave spherical surface. The front end of the rear needle body is provided with a first convex spherical surface that cooperates with the first concave spherical surface. The rear end of the front replaceable wear-resistant head is provided with a second convex spherical surface that cooperates with the second concave spherical surface.

[0007] As a preferred embodiment of the piercing needle used in an aluminum alloy seamless tube extrusion press according to this utility model, the intermediate stress buffer ring is made of a nickel-based high-temperature alloy.

[0008] As a preferred embodiment of the piercing needle used in the aluminum alloy seamless tube extrusion press of this utility model, the replaceable wear-resistant head at the front end is made of molybdenum-based alloy material.

[0009] As a preferred embodiment of the piercing needle for an aluminum alloy seamless tube extrusion press according to this utility model, the fastener is a high-strength bolt. The fastener passes through the through holes on the rear section of the needle body and the intermediate stress buffer ring in sequence, and is threadedly connected to the rear end of the front section replaceable wear-resistant head.

[0010] As a preferred embodiment of the piercing needle used in an aluminum alloy seamless tube extrusion machine according to this utility model, a high-temperature soft sealing gasket is provided at the interface between the second convex spherical surface and the second concave spherical surface.

[0011] As a preferred embodiment of the piercing needle used in the aluminum alloy seamless tube extrusion press of this utility model, the high-temperature soft sealing gasket is made of nickel-based high-temperature alloy soft foil.

[0012] The beneficial effects of this utility model are:

[0013] The three-section spherical connection structure effectively alleviates stress concentration at the connection point, significantly improving fatigue resistance and reliability. The use of replaceable wear-resistant heads significantly reduces maintenance costs. The spherical fit has a self-centering function to ensure centering accuracy. The high-temperature sealing structure prevents metal intrusion and ensures long-term stability. The overall structure balances high performance and low cost, making it particularly suitable for high-temperature and high-pressure aluminum alloy extrusion and piercing applications. Attached Figure Description

[0014] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0015] Figure 1This is a cross-sectional view of the present invention.

[0016] Figure 2 This is an enlarged structural diagram of part a of this utility model.

[0017] The markings in the diagram are: 1. Rear needle body; 2. Middle stress buffer ring; 3. Front replaceable wear-resistant head; 4. Fastener; 5. First concave spherical surface; 6. Second concave spherical surface; 7. First convex spherical surface; 8. Second convex spherical surface; 9. High-temperature soft sealing gasket. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments to aid in understanding its content. Unless otherwise specified, the methods used in this invention are conventional methods; the raw materials and apparatus used, unless otherwise specified, are conventional commercially available products.

[0019] Please see Figure 1-2 A piercing needle for an aluminum alloy seamless tube extrusion machine includes a needle body, which is composed of a rear needle body 1, an intermediate stress buffer ring 2, and a front replaceable wear-resistant head 3 connected in series by fasteners 4. The two end faces of the intermediate stress buffer ring 2 are respectively provided with a first concave spherical surface 5 and a second concave spherical surface 6. The front end of the rear needle body 1 is provided with a first convex spherical surface 7 that cooperates with the first concave spherical surface 5. The rear end of the front replaceable wear-resistant head 3 is provided with a second convex spherical surface 8 that cooperates with the second concave spherical surface 6.

[0020] In this embodiment, the needle body is composed of a rear needle body 1, a middle stress buffer ring 2, and a front replaceable wear-resistant head 3 connected in series by fasteners 4. The middle stress buffer ring 2 has a first concave spherical surface 5 and a second concave spherical surface 6 at both ends. The front end of the rear needle body 1 has a first convex spherical surface 7 that mates with the first concave spherical surface 5. The rear end of the front replaceable wear-resistant head 3 has a second convex spherical surface 8 that mates with the second concave spherical surface 6. The spherical mating structure transforms the connection from a rigid connection to a flexible floating connection. When subjected to eccentric load or thermal stress, the front end is allowed to generate adaptive micro-oscillation, which transforms concentrated stress into uniform compressive stress, significantly improving fatigue resistance. At the same time, the front end can be replaced separately, greatly reducing maintenance costs.

[0021] As a technical optimization of this utility model, the intermediate stress buffer ring 2 is made of nickel-based high-temperature alloy.

[0022] In this embodiment, the intermediate stress buffer ring 2 is made of a nickel-based high-temperature alloy. This material maintains excellent strength and toughness under high-temperature conditions and can effectively withstand the high pressure and thermal cycling load during the extrusion process, ensuring the long-term stability and reliability of the stress buffer function.

[0023] As a technical optimization of this utility model, the replaceable wear-resistant head 3 at the front end is made of molybdenum-based alloy material.

[0024] In this embodiment: the replaceable wear-resistant head 3 at the front end is made of molybdenum-based alloy material. Molybdenum-based alloy has extremely high high-temperature hardness, wear resistance and anti-aluminum liquid adhesion properties, directly dealing with the high-temperature aluminum ingot contact area, greatly extending the working life of the front end.

[0025] As a technical optimization of this utility model, the fastener 4 is a high-strength bolt. The fastener 4 passes through the through holes on the rear needle body 1 and the intermediate stress buffer ring 2 in sequence, and is threadedly connected to the rear end of the front replaceable wear-resistant head 3.

[0026] In this embodiment: the fastener 4 uses a high-strength bolt to connect the rear needle body 1 and the intermediate stress buffer ring 2, and is threaded to the front replaceable wear-resistant head 3. This structure provides a stable preload to ensure the overall connection rigidity. At the same time, the bolt connection method makes disassembly and assembly convenient and facilitates quick replacement of the front wear-resistant head.

[0027] As a technical optimization of this utility model, a high-temperature soft sealing gasket 9 is provided at the interface between the second convex spherical surface 8 and the second concave spherical surface 6.

[0028] In this embodiment: the high-temperature soft sealing gasket 9 maintains flexibility and sealing performance at high temperatures, effectively preventing aluminum metal from intruding into the spherical mating interface to avoid seizing, and ensuring the long-term effectiveness of the replaceable function.

[0029] As a technical optimization of this utility model, the high-temperature soft sealing gasket 9 is made of nickel-based high-temperature alloy soft foil.

[0030] In this embodiment: the high-temperature soft sealing gasket 9 is made of nickel-based high-temperature alloy soft foil, which can maintain flexibility and sealing performance at high temperatures.

[0031] The working principle and usage process of this utility model: The rear needle body 1 transmits axial pressure through the first convex spherical surface 7 and the first concave spherical surface 5 of the intermediate stress buffer ring 2. The front replaceable wear-resistant head 3 directly contacts the high-temperature aluminum ingot through the second convex spherical surface 8 and the second concave spherical surface 6 of the intermediate stress buffer ring 2. When subjected to eccentric force or thermal deformation, the intermediate stress buffer ring 2 allows the front replaceable wear-resistant head 3 to generate a small angle of sway through the spherical structure at both ends, so that the bending stress is converted into spherical contact compressive stress. At the same time, the fastener 4 composed of high-strength bolts provides sufficient pre-tightening force to maintain connection stability. The high-temperature soft sealing gasket 9 fills the gap of the spherical interface to prevent aluminum liquid from penetrating, thereby realizing the functions of stress buffering, sealing protection and quick replacement.

[0032] In the description of this utility model, it should be understood that the terms "left", "right", "up", "down", "top", "bottom", "front", "back", "inner", "outer", "back", "middle", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0033] However, the above description is only a specific embodiment of this utility model and should not be construed as limiting the scope of implementation of this utility model. Therefore, any substitution of equivalent components or equivalent changes and modifications made in accordance with the scope of protection of this utility model should still fall within the scope of the claims of this utility model.

Claims

1. A piercing needle for an aluminum alloy seamless tube extrusion press, comprising a needle body, characterized in that: The needle body is composed of three parts: a rear needle body (1), a middle stress buffer ring (2), and a front replaceable wear-resistant head (3), which are connected in series by fasteners (4). The two end faces of the middle stress buffer ring (2) are respectively provided with a first concave spherical surface (5) and a second concave spherical surface (6). The front end of the rear needle body (1) is provided with a first convex spherical surface (7) that matches the first concave spherical surface (5). The rear end of the front replaceable wear-resistant head (3) is provided with a second convex spherical surface (8) that matches the second concave spherical surface (6).

2. The piercing needle for an aluminum alloy seamless tube extrusion press according to claim 1, characterized in that: The intermediate stress buffer ring (2) is made of nickel-based high-temperature alloy.

3. The piercing needle for an aluminum alloy seamless tube extrusion press according to claim 1, characterized in that: The replaceable wear-resistant head (3) at the front end is made of molybdenum-based alloy material.

4. The piercing needle for an aluminum alloy seamless tube extrusion press according to claim 1, characterized in that: The fastener (4) is a high-strength bolt. The fastener (4) passes through the through holes on the rear needle body (1) and the intermediate stress buffer ring (2) in sequence, and is threaded to the rear end of the front replaceable wear-resistant head (3).

5. The piercing needle for an aluminum alloy seamless tube extrusion press according to claim 1, characterized in that: A high-temperature soft sealing gasket (9) is provided at the interface between the second convex spherical surface (8) and the second concave spherical surface (6).

6. The piercing needle for an aluminum alloy seamless tube extrusion press according to claim 5, characterized in that: The high-temperature soft sealing gasket (9) is made of nickel-based high-temperature alloy soft foil.

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