Magnetic heating of shape memory alloy pipe joints

Abstract

This utility model discloses a magnetically heated shape memory alloy pipe joint in the field of pipe fittings. It includes a coaxially arranged sleeve and a joint tube made of shape memory alloy. Shape memory alloy spring coils are located between the two ends of the joint tube and the sleeve. Multiple ferromagnetic heating blocks are arranged in a ring array on the outer wall of the middle part of the joint tube. Pressure sensors are located between the outer walls of the two ends of the joint tube and the inner walls of the spring coils. This utility model applies a specific magnetic field to the outside of the joint tube, causing the ferromagnetic heating blocks to generate eddy currents and heat up. This, in turn, causes the entire joint tube and spring coils to produce a thermal effect and deform uniformly. Simultaneously, the spring coils apply a clamping force to the joint tube, achieving a tight connection with the pipe being connected. During heating, the pressure signal fed back by the pressure sensors dynamically displays the connection status between the joint tube and the pipe being connected, thereby controlling the heating temperature and heating time. This improves resource utilization and ensures the tightness of the pipe joint.

Description

Technical Field

[0001] This utility model relates to the field of pipe joints, and in particular to a magnetically heated shape memory alloy pipe joint. Background Technology

[0002] Pipe fittings are parts in hydraulic systems that connect pipelines or mount pipelines onto hydraulic components. They are a general term for detachable connectors in fluid passages. They mainly include welded, compression fitting, and flared types. Types include end straight connectors, straight connectors, tees, elbows, connectors with live nuts, hinged connectors, plugs, and transition connectors. Shape memory pipe fittings are made of shape memory alloy materials. Shape memory alloys rely on the alloy's restoring force generated by the shape memory effect to clamp the connected pipes during the restoration process, achieving a tight connection. Therefore, heating devices are required when using shape memory alloy pipe fittings to connect pipelines. Traditional heating methods for shape memory alloy pipe fittings mainly use heating coils made of resistance wire, relying entirely on the experience of technicians. Temperature and heating effect are difficult to control, easily leading to resource waste, and the tightness of the joint is hard to guarantee. Utility Model Content

[0003] To overcome the aforementioned shortcomings of existing shape memory alloy pipe fittings during heating, the technical problem to be solved by this utility model is to provide a magnetically heated shape memory alloy pipe fitting that uses a conventional magnetic field to heat the pipe fitting.

[0004] The technical solution adopted by this utility model to solve its technical problem is: A magnetically heated shape memory alloy tube connector includes a sleeve and a connector tube made of shape memory alloy. The connector tube is coaxially disposed inside the sleeve. A spring ring made of shape memory alloy is provided between the outer wall of both ends of the connector tube and the inner wall of the sleeve. Multiple ferromagnetic heating blocks are arranged in a ring array on the outer wall of the middle part of the connector tube. A pressure sensor is provided between the outer wall of both ends of the connector tube and the inner wall of the spring ring.

[0005] Furthermore, the ferromagnetic heating blocks are provided in at least four layers along the axial direction of the connector tube, with at least three ferromagnetic heating blocks evenly distributed in each layer along the circumference of the connector tube.

[0006] Furthermore, the outer wall of the middle part of the connector tube is provided with multiple grooves, the inner end of the ferromagnetic heating block is nested in the grooves, and the outer end abuts against the inner wall of the sleeve.

[0007] Furthermore, the inner walls at both ends of the connector tube are provided with threaded structures.

[0008] Furthermore, the inner wall of the connector tube is coated with a wear-resistant coating.

[0009] The beneficial effects of this invention are as follows: By setting a ferromagnetic heating block on the outer wall of the connector tube, when a specific magnetic field is applied externally, eddy currents are generated in the ferromagnetic heating block, causing it to heat up. This results in a thermal effect and uniform deformation of the entire connector tube and the spring coil. The connector tube contracts and tightly connects with the pipe being connected. At the same time, the spring coil also contracts and applies a clamping force to the connector tube, thereby improving the reliability of the connection between the connector tube and the pipe being connected. In addition, during heating, the connection status between the connector tube and the pipe being connected can be dynamically displayed through the pressure signal fed back by the pressure sensor. This pressure can be correlated with the magnetic heating method to control the heating temperature and heating time, which can improve resource utilization and ensure the tightness of the pipe joint. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of this utility model.

[0011] The markings in the diagram are: 1-connector pipe, 2-sleeve, 3-spring ring, 4-ferromagnetic heating block, 5-pressure sensor, 6-threaded structure, 7-alternating magnetic field generator. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings.

[0013] It should be noted that if this utility model contains directional indicators such as up, down, left, right, front, and back, these terms are used to describe the relative positional relationships between components and are not specific references to the absolute positions of the components or the relationships between them. They are only used to explain the relative positional relationships and movement of the components in a specific posture. If the specific posture changes, the directional indicator will also change accordingly. If this utility model contains terms related to quantity such as "many," "multiple," or "several," these terms specifically refer to two or more.

[0014] like Figure 1 As shown, the present invention provides a magnetic heating shape memory alloy pipe connector, comprising a connector pipe 1 and a sleeve 2 made of shape memory alloy. The connector pipe 1 is coaxially disposed inside the sleeve 2. A spring coil 3 made of shape memory alloy is provided between the outer wall of both ends of the connector pipe 1 and the inner wall of the sleeve 2. Multiple ferromagnetic heating blocks 4 are arranged in a ring array on the outer wall of the middle part of the connector pipe 1. Pressure sensors 5 are provided on the inner wall of both ends of the connector pipe 1 and between the outer wall of the connector pipe 1 and the spring coil 3.

[0015] The sleeve 2 can be made of a common metal material with a certain structural strength to protect the internal connector tube 1. Invar alloy, specifically Fe-Ni36, is preferred due to its low expansion characteristics, which prevent deformation of the connector tube 1 during heating. The sleeve 2 can have a fixed retaining ring at one end and a detachable retaining ring at the other end to axially limit the connector tube 1. A spring ring 3 provides radial limiting between the connector tube 1 and the sleeve 2, ensuring a secure connection. The connector tube 1 is made of nickel-chromium-aluminum alloy and formed by casting. Appropriate heat treatment and shape memory training ensure it possesses good shape memory effect, allowing it to shrink under heat and return its cross-sectional shape from elliptical to circular. The ferromagnetic heating block 4 on the connector tube 1 can be made of ordinary cast iron or magnetic stainless steel. The spring ring 3 uses a shape memory alloy with better shape memory effect than the connector tube 1, meaning the deformation of the spring ring 3 after heating is greater than that of the connector tube 1, such as a Ti-Al-Cr alloy. This allows the spring ring 3 to provide clamping force to the connector tube 1 after heating. When installing the spring coil 3 between the connector pipe 1 and the sleeve 2, grooves can be provided on the outer wall of the connector pipe 1 and the inner wall of the sleeve 2 to limit the movement of the spring coil 3. Additionally, during installation, it is essential to ensure that the spring coil 3 undergoes a certain degree of compression deformation. This ensures that even after the spring coil 3 contracts due to heat, its outer ring still abuts against the inner wall of the sleeve 2, thus guaranteeing a secure connection between the connector pipe 1 and the sleeve 2. The pressure sensor 5 is preferably a resistive strain gauge, which is connected to an external pressure display device via a signal line. The signal line and display device can be removed after the pipeline connection is completed, or they can be retained for real-time monitoring of the tightening pressure during subsequent working stages.

[0016] The process of using this utility model is as follows: First, insert the two pipes to be connected into the two ends of the connector pipe 1. Then, use the alternating magnetic field generator 7 to cover the entire connector pipe 1. There are many small alternating magnetic field generators on the market, which can be purchased directly according to needs. Alternatively, an alternating magnetic field generator can be made by using coils and frequency converters according to actual conditions. Finally, use the magnetic field generated by the alternating magnetic field generator 7 to heat the ferromagnetic heating block 4, causing the connector pipe 1 and spring coil 3 to shrink under the action of thermal effect and tightly connect with the pipes. At the same time, due to the large deformation of the spring coil 3, it squeezes the connector pipe 1, causing the pressure detected by the pressure sensor 5 to change. When the pressure reaches the set threshold, it can be proven that the connector pipe 1 and the pipes are tightly connected. At this time, the alternating magnetic field generator can be turned off to complete the pipe docking work.

[0017] To ensure that the ferromagnetic heating blocks 4 heat the joint pipe 1 evenly, based on the general pipe size and overlap length, the ferromagnetic heating blocks 4 are preferably arranged in at least four layers evenly spaced along the axial direction of the joint pipe 1, with at least three ferromagnetic heating blocks 4 evenly distributed in each layer along the circumference of the joint pipe 1. This saves materials and ensures that there are enough ferromagnetic heating blocks 4 to heat the joint pipe 1 evenly.

[0018] When installing the ferromagnetic heating block 4, multiple grooves can be provided on the outer wall of the middle part of the connector tube 1. The inner end of the ferromagnetic heating block 4 is nested in the groove, and the outer end abuts against the inner wall of the sleeve 2. The ferromagnetic heating block 4 can be fixedly connected to the connector tube 1 by adhesive bonding, and a certain gap can be reserved between the inner end of the ferromagnetic heating block 4 and the side wall of the groove so that when the connector tube 1 shrinks, the ferromagnetic heating block 4 will not abut against the groove and affect the deformation of the connector tube 1.

[0019] Furthermore, to improve the reliability of the connection between the connector pipe 1 and the connected pipe, threaded structures 6 are provided on the inner walls at both ends of the connector pipe 1. The threaded structures 6 can increase the friction between the connector pipe 1 and the connected pipe, thereby preventing detachment. In addition, a wear-resistant coating can be sprayed onto the inner wall of the connector pipe 1 to improve the wear resistance and corrosion resistance of the pipe joint and extend the service life of the entire pipe joint.

[0020] This invention utilizes a ferromagnetic heating block 4 on the outer wall of the connector tube 1. When a specific magnetic field is applied externally, eddy currents are generated within the ferromagnetic heating block 4, causing it to heat up. This heats the entire connector tube 1 and the spring coil 3, causing them to deform uniformly. The connector tube 1 contracts and tightly connects with the pipe being connected. Simultaneously, the spring coil 3 also contracts, applying a clamping force to the connector tube 1, thereby improving the reliability of the connection between the connector tube 1 and the pipe being connected. Furthermore, during heating, the connection status between the connector tube 1 and the pipe being connected can be dynamically displayed through the pressure signal fed back by the pressure sensor 5. This pressure can be correlated with the magnetic heating method to control the heating temperature and heating time. This not only improves resource utilization but also ensures the tightness of the pipe joint, demonstrating excellent practicality and application value.

Claims

1. A magnetically heated shape memory alloy tube connector, comprising a connector tube (1) made of shape memory alloy material, characterized in that: It also includes a sleeve (2), the connector tube (1) is coaxially arranged inside the sleeve (2), and a spring ring (3) made of shape memory alloy is provided between the outer wall of both ends of the connector tube (1) and the inner wall of the sleeve (2). Multiple ferromagnetic heating blocks (4) are arranged in a ring array on the outer wall of the middle part of the connector tube (1), and a pressure sensor (5) is provided between the outer wall of both ends of the connector tube (1) and the inner wall of the spring ring (3).

2. The magnetically heated shape memory alloy pipe joint as described in claim 1, characterized in that: The ferromagnetic heating block (4) is provided in at least four layers along the axial direction of the connector tube (1), and at least three ferromagnetic heating blocks (4) are evenly distributed in each layer along the circumferential direction of the connector tube (1).

3. The magnetically heated shape memory alloy pipe joint as described in claim 2, characterized in that: The outer wall of the middle part of the connector tube (1) is provided with multiple grooves, the inner end of the ferromagnetic heating block (4) is nested in the grooves, and the outer end abuts against the inner wall of the sleeve (2).

4. The magnetically heated shape memory alloy pipe joint as described in claim 1, characterized in that: The inner walls at both ends of the connector tube (1) are provided with threaded structures (6).

5. The magnetically heated shape memory alloy pipe joint as described in claim 4, characterized in that: The inner wall of the connector tube (1) is coated with a wear-resistant coating.

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