A heat exchanger tube forming mold for a gas heating hot water boiler

Abstract

The present invention relates to the technical field of heat exchange tube forming dies, and specifically to a heat exchange tube forming die for a gas heating hot water boiler, comprising a die seat, a die body, an extrusion column and a guide column, wherein the guide column is provided with a material taking component, and the material taking component is provided with a bayonet and a driving rod, wherein the bayonet is symmetrically installed on both sides of the central axis of the guide column, and a driving groove is coaxially opened in the guide column, and one end of the bayonet close to the central axis of the guide column extends into the driving groove, and the driving rod is slidably connected in the driving groove, and when the guide column moves to the material head position, the end face of the bayonet away from the central axis of the guide column will contact the inner circle of the material head, and further, when the extrusion column and the guide column are separated from the die seat, the material head will be separated from the guide column, thereby avoiding the problem that the heat exchange tube forming die has a depth and is inconvenient to remove the material head, thereby ensuring the rapid removal of the material head inside the heat exchange tube forming die while improving production efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchange tube forming dies, in particular to a heat exchange tube forming die for a heat exchanger used in a gas heating hot water boiler. Background Art

[0002] A gas heating water heater is a common household heating device used to provide heating and hot water services. A typical gas heating water heater includes a combustion chamber, a heat exchanger, a water pump, a control system and other components. A gas heating water heater heats water by burning gas (such as natural gas or liquefied petroleum gas), and then transports the hot water through pipes to the heating system or hot water tap to supply heating and hot water. A heat exchanger is a device used to transfer heat. It can transfer heat from one fluid to another without direct contact between the two. A heat exchanger is usually composed of components such as pipes, tube sheets, shells and heat transfer surfaces. Its working principle is based on heat transfer mechanisms such as heat conduction, convection and radiation. The heat exchange tube is one of the components of the heat exchanger. It is used to exchange heat between two media. It has good thermal conductivity and isothermal properties. It is a component that can quickly transfer heat energy from one point to another. The main components of the heat exchange tube include the tube body and the tube wall. The tube body is usually made of metal materials such as copper, stainless steel, aluminum, etc., with good thermal conductivity and corrosion resistance. The production of heat exchange tubes is achieved through extrusion, rolling, welding, tube drawing and rolling.

[0003] The heat exchanger tubes of the heat exchanger for gas heating hot water boilers are usually made of pipes with smaller diameters, and the extrusion production of heat exchanger tubes is suitable for the production of pipes with smaller diameters. The heat exchanger tubes are usually extruded by forming die extrusion in the extrusion production. Forming die extrusion is an extrusion process in which a metal blank is extruded into a workpiece along the cross-sectional shape of the mold cavity by the pressure of the forming die. Forming die extrusion is usually suitable for manufacturing parts with relatively simple cross-sectional shapes, such as round, square, rectangular, etc. During the extrusion process, the metal blank is fed into the inlet of the extrusion die, and is extruded from the outlet of the die under the extrusion force of the forming die to form the desired cross-sectional shape; in the extrusion production process of the heat exchanger tube, a certain length of the material head is usually left to prevent dirt from entering the interior of the product in the later stage of extrusion, and to prevent the extrusion gasket and the extrusion die from contact and collision, but the forming die has a depth, which makes it inconvenient to remove the material head.

[0004] In response to the above problems, the prior art has proposed some solutions. For example, Chinese patent application number: CN202110207576.5 provides a tin-bismuth solder strip and a continuous production process thereof. The continuous production process of the tin-bismuth solder strip comprises the following steps: (1) preheating the tin-bismuth alloy ingot and then hot extruding it; (2) secondary heating the hot-extruded material head, and then shearing it, and then adding the next preheated tin-bismuth alloy ingot for hot extrusion to obtain the tin-bismuth solder strip; in the step (2), the secondary heating temperature is 60-200°C; the present invention adopts the method of secondary heating residual pressure and shearing residual pressure to realize the continuous production process. The process can soften the billet and reduce the pressure requirement for shearing the billet, so as to achieve a balance between the billet temperature and the temperature of the next billet, and make the internal temperature field of the next billet uniform when it is extruded; on the other hand, the tail of the billet is sheared to combine the billet with the surface of the next billet, and at the same time, the key points of the production process are regulated to achieve the purpose of refining the material organization and improving the material processing performance; however, this solution requires the installation of a secondary heating element in the mold to perform secondary heating on the billet, which further increases the processing cost of the heat exchange tube, which is a burden for some small-scale or budget-limited manufacturers, and the quality of the finished heat exchange tube is reduced due to the inability to smoothly combine the billet with the next billet.

[0005] Therefore, in view of the problem that the forming mold has a depth and is inconvenient to remove the material head, a forming mold for a heat exchanger tube of a heat exchanger for a gas heating hot water boiler is proposed. Summary of the invention

[0006] The object of the present invention is to provide a forming die for heat exchange tubes of a heat exchanger for a gas heating hot water boiler, so as to solve the problem that the forming die has a depth and is inconvenient for removing the material head.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A heat exchange tube forming mold for a gas heating hot water boiler, comprising a mold base, a mold body, an extrusion column and a guide column. The mold base, the mold body, the extrusion column and the guide column are coaxially installed in sequence. The guide column is provided with a material picking assembly, and the material picking assembly is provided with a bayonet and a drive rod. The bayonet is symmetrically installed on both sides of the central axis of the guide column. A drive groove is coaxially opened in the guide column, and one end of the bayonet close to the central axis of the guide column extends into the drive groove. The drive rod is slidably connected in the drive groove. When the drive rod moves to the bayonet position, the bayonet moves in a direction away from the central axis of the guide column.

[0009] When the heat exchange tube forming mold extrude the material blank, the material blank is added into the mold seat, the extrusion column and the guide column move into the mold seat, and the guide column moves toward the mold body. When the guide column moves into place, the extrusion column extrude the material blank. At this time, the material blank is pressed and extruded toward the mold body, and is guided by the guide column to form a round tube. When the extrusion of the material blank is completed, a certain gap will be left between the mold body and the extrusion column to prevent the extrusion column and the mold body from contacting and colliding. A material head is left in the gap. Further, the guide column moves toward the extrusion column. When the guide column moves to the material head position, the driving rod moves toward the mold body and pushes The pin moves in the direction away from the central axis of the guide column. At this time, the end face of the pin away from the central axis of the guide column will contact the inner circle of the material head. Further, the extrusion column and the guide column move in the direction away from the mold body. When the extrusion column and the guide column are separated from the mold seat, the drive rod moves in the direction away from the mold body. At this time, the pin will move in the direction of the central axis of the guide column, and the guide column also moves away from the mold body. After this action is completed, the material head will be separated from the guide column, avoiding the problem of depth of the heat exchange tube forming mold and inconvenience in removing the material head, ensuring the rapid removal of the material head inside the heat exchange tube forming mold while improving production efficiency.

[0010] Optionally, the material picking component includes a pneumatic clamp, an electric clamp and a magnetic clamp. All of the above three components can clamp the material head. The pneumatic clamp uses a pneumatic cylinder and a control valve to control the airflow to achieve the function of clamping, releasing or moving the workpiece. The advantages include fast operation speed, flexible movement, high reliability, and easy integration with other pneumatic components. However, the pneumatic clamp may require additional air source devices and pipelines, which are more complex. The electric clamp realizes the material picking operation through the electric principle. It uses an electric drive device, such as a motor, servo drive or stepper motor, to drive the movement of the clamp. The advantages of the electric clamp include It has high operating accuracy, adjustable force, and is easy to control and integrate into the automation system. However, electric clamps may be limited by the torque, speed, and accuracy of the electric drive device. Magnetic clamps use the magnetic principle to achieve material picking operations. They use electromagnets or permanent magnets to generate magnetic force to adsorb or release workpieces. The advantages of magnetic clamps include easy operation, no need for additional power sources, and suitability for smaller workpieces. However, the adsorption force of magnetic clamps may be limited by the material and surface conditions of the workpiece, and attention should be paid to objects or equipment that are sensitive to magnetic fields when using them. Therefore, the above three material picking components are not preferred solutions of the present invention.

[0011] Preferably, the material picking assembly includes a pin, a driving rod, a driving block and a spring leaf, a slide groove is opened in the front end of the guide column, the pin is slidably connected to the two ends of the slide groove, the end of the pin away from the central axis of the guide column is flush with the outer ring of the guide column, the driving block is installed on the front end surface of the driving rod, the cross-section of the driving block in the direction perpendicular to the central axis of the guide column is an isosceles triangle, and the spring leaf is installed between the pin and the guide column.

[0012] The material taking assembly is used to clamp and take out the material head. When the extrusion column squeezes the blank, the pin is supported by the pressure of the spring and remains in the slide groove. At the same time, the driving rod and the driving block are also inactive. When the extrusion column completes the extrusion of the blank, the guide column will move to the material head position. At this time, the driving rod moves toward the mold body and pushes the pin to move away from the central axis of the guide column through the driving block. The end face of the pin away from the central axis of the guide column will contact the inner circle of the material head, thereby completing the clamping action, avoiding the problem that the heat exchange tube forming mold has a depth and is inconvenient to take out the material head, ensuring the rapid removal of the material head inside the heat exchange tube forming mold while improving production efficiency.

[0013] Preferably, a mounting groove is coaxially provided at the front end of the extrusion column, and an edge sealing ring is slidably connected in the mounting groove, the inner ring of the edge sealing ring is flush with the outer ring of the guide column, and the edge sealing ring is provided with a number of slots corresponding to the bayonet pin, and the cross-sectional size of the slots is the same as that of the slide grooves, and the edge sealing ring is used to cut off the connection between the forming tube and the material head. When the extrusion column completes the extrusion of the blank, the guide column will move to the position of the extrusion column and be flush with the front end face of the extrusion column. At this time, the driving rod moves toward the direction of the mold body and pushes the bayonet pin to move in the direction away from the central axis of the guide column through the driving block, and the end face of the bayonet pin away from the central axis of the guide column will be flush with the outer ring of the edge sealing ring, thereby The action of clamping the edge sealing ring is completed. Furthermore, in the process of the guide column and the edge sealing ring moving toward the mold body, since the outer ring of the edge sealing ring is larger than the inner ring of the material head, the inner ring of the material head will be scraped off by the edge sealing ring and accumulated in the direction of the forming tube. When the guide column and the edge sealing ring move to the position of the mold body, since the outer ring of the edge sealing ring is equal to the inner ring of the mold body, the connection between the material head and the forming tube will be cut off at this time, and the material blank on the front end face of the guide column and the edge sealing ring will be accumulated on the rear end face of the forming tube, so that the rear end face of the forming tube is closed, avoiding the problem of dirt entering the inside of the forming tube in the later stage of extrusion, and ensuring the molding quality of the heat exchange tube forming mold.

[0014] Preferably, a protrusion is provided on the end surface of the pin away from the central axis of the guide column, and the protrusion is heat-treated and has a hardness greater than 40HRC. The protrusion is used to increase the friction coefficient between the pin and the material head. When the end surface of the pin away from the central axis of the guide column contacts the inner ring of the material head, since the blank is heated and then extruded, the hardness of the material head will be less than 10HRC at this time. The protrusion that has been heat-treated can be easily embedded in the material head, avoiding the slipping of the pin due to the low friction coefficient when clamping the material head, making it inconvenient to remove the material head, ensuring the rapid removal of the material head inside the heat exchange tube forming mold while improving production efficiency.

[0015] Preferably, a roller is installed on the pin, and the roller is located at one end of the pin close to the central axis of the guide column. The angle between the slide groove and the central axis of the guide column is α, and the value range of α is 45°≤α≤75°. The roller is used to reduce the sliding friction between the pin and the drive block, thereby ensuring the service life of the drive block and the pin. When the pin clamps the material head and moves away from the mold body, the pin will generate a pulling force on the material head. At this time, the angle α decomposes the pulling force between the pin and the material head and generates a component force parallel to the slide groove. When the mass and surface roughness are the same, a larger angle (contact angle) can generate a greater friction. Suppose there is an object tilted on an inclined plane with an angle of θ. In this case, the component force perpendicular to the inclined plane (vertical component force) is determined by the mass of the object, which is mg*cos(θ), where m is the mass of the object. Where g is the acceleration of gravity, and the component force parallel to the inclined plane (parallel component force) is determined by the friction coefficient μ and the vertical component force, which is μ*mg*cos(θ). Therefore, the friction force F is determined by the parallel component force, that is, F=μ*mg*cos(θ). In the above formula, the mass m and the surface roughness are jointly determined by the acceleration of gravity g and the friction coefficient μ. When the mass and surface roughness are given, the change of the angle θ will directly affect the change of cos(θ), thereby determining the size of the vertical component force and the friction force. In this scheme, in order to increase the clamping force of the bayonet on the material head and ensure the elongation of the bayonet, the angle α is set to 60° to avoid the slipping of the bayonet pin due to the problem of too low friction when clamping the material head, which makes it inconvenient to remove the material head, thereby ensuring the rapid removal of the material head inside the heat exchange tube forming mold and improving production efficiency.

[0016] Preferably, the pin is provided with a friction portion and a support portion, the support portion is in an I-shape, the friction portion is located in grooves on both sides of the support portion, the two friction portions are respectively slidably connected to the front and rear side walls of the slide groove, the support portion is made of nickel-based alloy, and the friction portion is made of wear-resistant material, thereby ensuring the wear resistance of the contact surface between the pin and the slide groove, and the support portion is used to increase the pressure resistance of the contact surface between the protrusion and the material head. When the protrusion contacts the material head, since the nickel-based alloy performs well under high temperature conditions and has good creep resistance and high-temperature oxidation resistance, the problem of deformation of the pin due to too low creep resistance coefficient when clamping the material head is avoided, thereby ensuring the rapid removal of the material head inside the heat exchange tube forming mold.

[0017] Preferably, the driving rod is coaxially provided with a conveying path, and both ends of the conveying path are respectively connected with the rear end of the driving rod and the inside of the slide groove. Cooling liquid flows in the conveying path, and the coolant is used to cool the guide column moving toward the mold body, thereby avoiding the problem of damage to the mold body due to thermal expansion of the material when the edge sealing ring contacts the mold body, thereby ensuring the integrity of the heat exchange tube forming mold.

[0018] Preferably, a plurality of cooling channels are evenly distributed on the inner end surface of the support portion, and the plurality of cooling channels are countersunk holes, and the plurality of cooling channels are connected to the inside of the slide groove, and the plurality of cooling channels are circular. The cooling channels are used to cool the bayonet when clamping the material head, thereby avoiding the problem of deformation of the bayonet due to excessively high temperature when clamping the material head, and ensuring the rapid removal of the material head inside the heat exchange tube forming mold.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention arranges a material taking component in the guide column. When the driving rod moves toward the mold body, the bayonet will move away from the central axis of the guide column and clamp the inner circle of the material head. When the extrusion column and the guide column are separated from the mold seat, the driving rod moves away from the mold body. At this time, the bayonet will move in the direction of the central axis of the guide column, and the guide column will also move away from the mold body. After this action is completed, the material head will be separated from the guide column, avoiding the problem that the heat exchange tube forming mold has a depth and is inconvenient to take out the material head, ensuring the rapid removal of the material head inside the heat exchange tube forming mold while improving production efficiency.

[0021] 2. The present invention arranges an installation groove and an edge sealing ring in the extrusion column. When the guide column and the edge sealing ring move toward the mold body, the inner circle of the material head will be scraped off by the edge sealing ring and accumulated in the direction of the forming tube because the outer circle of the edge sealing ring is larger than the inner circle of the material head. When the guide column and the edge sealing ring move to the position of the mold body, the connection between the material head and the forming tube will be cut off, and the material blank on the front end surface of the guide column and the edge sealing ring will be accumulated on the rear end surface of the forming tube, so that the rear end surface of the forming tube is in a closed state, avoiding the problem of dirt entering the interior of the forming tube in the later stage of extrusion, thereby ensuring the molding quality of the heat exchange tube molding mold.

[0022] 3. The present invention provides a protrusion on the end face of the bayonet away from the central axis of the guide column. When the end face of the bayonet away from the central axis of the guide column contacts the inner ring of the material head, since the blank is heated and then extruded, the hardness of the material head will be less than 10HRC at this time. The protrusion processed by heat treatment can be easily embedded in the material head, avoiding the problem of the bayonet pin slipping due to the low friction coefficient when clamping the material head, making it inconvenient to remove the material head, and ensuring the rapid removal of the material head inside the heat exchange tube forming mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of a heat exchange tube forming mold for a heat exchanger for a gas-fired heating hot water boiler of the present invention;

[0024] Figure 2 It is a schematic structural diagram of the heat exchange tube forming mold for the gas-fired heating hot water boiler of the present invention after the material blank is sheared by the edge sealing ring;

[0025] Figure 3 It is a structural schematic diagram of the heat exchange tube forming mold for the gas heating hot water boiler of the present invention after the material head is clamped and pulled out by the clamping assembly;

[0026] Figure 4 For the present invention Figure 1 Sectional view at AA;

[0027] Figure 5 It is a cross-sectional view of the heat exchange tube forming die for the heat exchanger for the gas heating hot water boiler of the present invention after the guide column drives the edge sealing ring to cut the blank;

[0028] Figure 6 It is a cross-sectional view of the heat exchange tube forming mold for the gas heating hot water boiler of the present invention after the material head is clamped by the clamping pin;

[0029] Figure 7 It is a structural schematic diagram of a latch in a heat exchange tube forming die for a heat exchanger for a gas-fired heating hot water boiler according to the present invention;

[0030] Figure 8 For the present invention Figure 7 Sectional view at the middle BB;

[0031] In the figure: 1. mold base; 2. mold body; 3. extrusion column; 4. guide column; 5. material removal assembly; 501. latch; 502. drive rod; 503. drive block; 504. spring; 505. slide groove; 506. mounting groove; 507. edge banding ring; 508. slot; 509. protrusion; 510. roller; 511. friction part; 512. support part; 513. groove; 514. conveying channel; 515. cooling channel; 516. drive groove; 517. coolant; 6. blank; 7. material head; 8. forming tube; S1: blank extrusion direction; S2: material head removal direction. DETAILED DESCRIPTION

[0032] See also Figures 1 to 8 The present invention provides a heat exchange tube forming die for a gas heating hot water boiler, and the technical solution is as follows:

[0033] A heat exchanger tube forming mold for a gas heating hot water boiler, please refer to Figure 1 , including a mold base 1, a mold body 2, an extrusion column 3 and a guide column 4, wherein the mold base 1, the mold body 2, the extrusion column 3 and the guide column 4 are coaxially installed in sequence, and a material taking component 5 is provided on the guide column 4.

[0034] See also Figures 4 to 6 The front end of the extrusion column 3 is coaxially provided with a mounting groove 506, and a sealing ring 507 is slidably connected in the mounting groove 506. The inner ring of the sealing ring 507 is flush with the outer ring of the guide column 4. The sealing ring 507 is provided with a number of slots 508 corresponding to the bayonet 501, and the cross-sectional size of the slots 508 is the same as that of the slide groove 505.

[0035] See also Figures 4 to 8 The material taking assembly 5 includes a latch 501, a driving rod 502, a driving block 503 and a spring 504. A slide groove 505 is provided in the front end of the guide column 4. The angle between the slide groove 505 and the central axis of the guide column 4 is 60°. The latch 501 is slidably connected to both ends of the slide groove 505. The latch 501 is provided with a friction part 511 and a support part 512. Please refer to Figure 8The support portion 512 is in an I-shape, the friction portion 511 is located in the grooves 513 on both sides of the support portion 512, and a plurality of cooling channels 515 are evenly distributed on the inner end surface of the support portion 512. The plurality of cooling channels 515 are countersunk holes, and the plurality of cooling channels 515 are connected to the inside of the slide 505. The plurality of cooling channels 515 are circular, and the two friction portions 511 are respectively slidably connected to the front and rear side walls of the slide 505. The support portion 512 is made of a nickel-based alloy, and the friction portion 511 is made of a wear-resistant material. The end of the bayonet 501 away from the central axis of the guide column 4 is flush with the outer ring of the guide column 4. A protrusion 509 is provided on the end surface of the bayonet 501 away from the central axis of the guide column 4. The protrusion 509 is heat-treated and has a hardness greater than 40HRC. A roller 510 is installed on the pin 501, and the roller 510 is located at one end of the pin 501 close to the central axis of the guide column 4. A driving groove 516 is coaxially opened in the guide column 4, and one end of the pin 501 close to the central axis of the guide column 4 extends into the driving groove 516. The driving rod 502 is slidably connected in the driving groove 516, and the driving block 503 is installed on the front end surface of the driving rod 502. The cross-section of the driving block 503 in the vertical direction of the central axis of the guide column 4 is an isosceles triangle. The spring leaf 504 is installed between the pin 501 and the guide column 4. The driving rod 502 is coaxially opened with a conveying path 514, and the two ends of the conveying path 514 are respectively connected with the rear end of the driving rod 502 and the inside of the slide groove 505, and a coolant 517 flows in the conveying path 514.

[0036] While working, see Figures 1 to 8 When the heat exchange tube forming die is extruding the material blank 6, the material blank 6 is added to the die seat 1, and the extrusion column 3 and the guide column 4 move in the direction of S1. When the guide column 4 moves into place, the extrusion column 3 extrude the material blank 6. At this time, the material blank 6 is pressed and extruded toward the die body 2, and is guided by the guide column 4 to form a round tube. Please refer to Figure 4 At the same time, the latch 501 is supported by the pressure of the spring 504 and remains in the slide groove 505. At the same time, the driving rod 502 and the driving block 503 are also inactive. After the extrusion of the blank 6 is completed, a certain gap will be left between the die body 2 and the extrusion column 3 to prevent the extrusion column 3 and the die body 2 from contacting and colliding. The blank 7 is left in the gap.

[0037] For further information, see Figure 2 and Figure 5, when the extrusion column 3 completes the extrusion of the blank 6, the guide column 4 will move to the position of the extrusion column 3 and be flush with the front end face of the extrusion column 3. At this time, the driving rod 502 moves in the direction of S1 and pushes the latch 501 to move away from the central axis of the guide column 4 through the driving block 503. The end face of the latch 501 away from the central axis of the guide column 4 will be flush with the outer ring of the edge banding ring 507, thereby completing the action of clamping the edge banding ring 507. In the process of the guide column 4 and the edge banding ring 507 moving in the direction of S1, since the outer ring of the edge banding ring 507 is larger than the inner ring of the material head 7, the inner ring of the material head 7 will be scraped off by the edge banding ring 507 and accumulated in the direction of the forming tube 8. When the heat exchange tube forming mold is in the position, since the outer circle of the edge sealing ring 507 is equal to the inner circle of the mold body 2, the connection between the material head 7 and the forming tube 8 will be cut off, and the guide column 4 and the material blank 6 on the front end face of the edge sealing ring 507 will be accumulated on the rear end face of the forming tube 8, so that the rear end face of the forming tube 8 forms a closed state, avoiding the problem of dirt entering the inside of the forming tube 8 in the later stage of extrusion, ensuring the forming quality of the heat exchange tube forming mold, and at the same time, the coolant 517 circulating in the conveying channel 514 cools down the guide column 4 and the edge sealing ring 507 moving in the S1 direction, avoiding the problem of damage to the mold body 2 due to thermal expansion of the material when the edge sealing ring 507 contacts with the mold body 2.

[0038] For further information, see Figure 3 and Figure 6 , when the connection between the material head 7 and the forming tube 8 is cut off, the guide column 4 moves in the direction of S2. When the guide column 4 moves to the position of the material head 7, the driving rod 502 moves in the direction of the mold body 2 and pushes the roller 510 on the bayonet 501 through the driving block 503 to make the bayonet 501 move in the direction away from the central axis of the guide column 4. The roller 510 is used to reduce the sliding friction between the bayonet 501 and the driving block 503, thereby ensuring the service life of the driving block 503 and the bayonet 501. At this time, the end face of the bayonet 501 away from the central axis of the guide column 4 will contact the inner ring of the material head 7. Since the blank 6 is heated and then moved The material head 7 is formed and extruded, so the hardness of the material head 7 will be less than 10HRC at this time. The protrusion 509 that has been heat treated can be easily embedded in the material head 7, and when the protrusion 509 contacts the material head 7, since the nickel-based alloy performs well under high temperature conditions and has good creep resistance and high-temperature oxidation resistance, the problem of deformation of the bayonet 501 due to the low creep resistance coefficient when the bayonet 501 is clamped in the material head 7 is avoided. At the same time, the cooling channel 515 in the support part 512 cools the bayonet 501, further avoiding the problem of deformation of the bayonet 501 due to excessively high temperature when the bayonet 501 is clamped in the material head 7.

[0039] For further information, see Figure 3, the extrusion column 3 and the guide column 4 move in the direction of S2. When the extrusion column 3 and the guide column 4 are separated from the mold base 1, the driving rod 502 moves in the direction of S2. At this time, the pin 501 will move in the direction of the central axis of the guide column 4. At the same time, the guide column 4 also moves in the direction of S2. After the action is completed, the material head 7 will be separated from the guide column 4, avoiding the problem that the heat exchange tube forming mold has a depth and is inconvenient to remove the material head 7, thereby ensuring the molding quality and integrity of the heat exchange tube forming mold.

[0040] A specific embodiment of the present invention is described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above described embodiment. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments without departing from the principles and ideas of the present invention should still fall within the scope of protection of the present invention.

Claims

1. A heat exchanger tube forming die for a gas heating water heater, comprising a die base (1), a die body (2), an extrusion column (3) and a guide column (4), wherein the die base (1), the die body (2), the extrusion column (3) and the guide column (4) are coaxially sleeved and installed in sequence, and characterized in that: The guide column (4) is provided with a material taking assembly (5), and the material taking assembly (5) comprises a bayonet (501), a driving rod (502), a driving block (503) and a spring leaf (504). The bayonet (501) is symmetrically mounted on both sides of the central axis of the guide column (4). A driving groove (516) is coaxially provided in the guide column (4). One end of the bayonet (501) close to the central axis of the guide column (4) extends into the driving groove (516). The driving rod (502) is slidably connected in the driving groove (516). When the driving rod (502) moves to the bayonet (501) position, The bayonet (501) moves in a direction away from the central axis of the guide column (4); a slide groove (505) is provided in the front end of the guide column (4); the bayonet (501) is slidably connected to the two ends of the slide groove (505); the end of the bayonet (501) away from the central axis of the guide column (4) is flush with the outer ring of the guide column (4); the driving block (503) is installed on the front end surface of the driving rod (502); the cross section of the driving block (503) in the direction perpendicular to the central axis of the guide column (4) is an isosceles triangle; the spring leaf (504) is installed between the bayonet (501) and the guide column (4).

2. The heat exchange tube forming mold for a gas heating water heater according to claim 1, characterized in that: The front end of the extrusion column (3) is coaxially provided with a mounting groove (506), and a sealing ring (507) is slidably connected in the mounting groove (506). The inner ring of the sealing ring (507) is flush with the outer ring of the guide column (4). The sealing ring (507) is provided with a number of slots (508) corresponding to the number of the bayonet pins (501), and the cross-sectional size of the slots (508) is the same as that of the slide groove (505).

3. The heat exchange tube forming mold for a gas heating water heater according to claim 2, characterized in that: A protrusion (509) is provided on the end surface of the latch (501) away from the central axis of the guide column (4); the protrusion (509) is heat-treated and has a hardness greater than 40HRC.

4. The heat exchange tube forming mold for a gas heating water heater according to claim 3, characterized in that: A roller (510) is mounted on the bayonet (501), and the roller (510) is located at one end of the bayonet (501) close to the central axis of the guide column (4). The included angle between the slide groove (505) and the central axis of the guide column (4) is α, and the value range of α is 45°≤α≤75°.

5. The heat exchange tube forming mold for a gas heating water heater according to claim 2, characterized in that: The latch (501) is provided with a friction portion (511) and a support portion (512); the support portion (512) is in an I-shape; the friction portion (511) is located in grooves (513) on both sides of the support portion (512); the two friction portions (511) are respectively slidably connected to the front and rear side walls of the slide groove (505); and the support portion (512) is made of a nickel-based alloy.

6. The heat exchange tube forming mold for a gas heating water heater according to claim 2, characterized in that: The driving rod (502) is coaxially provided with a conveying path (514), and two ends of the conveying path (514) are respectively connected to the rear end of the driving rod (502) and the inside of the sliding groove (505).

7. The heat exchange tube forming mold for a gas heating water heater according to claim 5, characterized in that: A plurality of cooling channels (515) are evenly distributed on the inner end surface of the support portion (512), and the plurality of cooling channels (515) are all countersunk holes, and the plurality of cooling channels (515) are all connected to the inside of the slide groove (505), and the plurality of cooling channels (515) are all circular.

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