Jet type heat treatment device suitable for cavity structure with large length-diameter ratio and wall thickness

Abstract

The utility model discloses a jet type heat treatment device suitable for a cavity structure with large length-diameter ratio and wall thickness, which comprises a placing table, a cavity structure to be subjected to heat treatment can be placed on the placing table and fixed, a jet device is arranged at one end of the placing table, the jet device comprises a plurality of jet pipes, jet holes are arranged on the jet pipes, and the jet holes are communicated with the placing table. The jet pipe can be inserted into the cavity structure and connected with the high-pressure jet pump, and the high-pressure jet pump provides power for cooling liquid needed by heat treatment and can spray the cooling liquid out of the jet holes in the jet pipe so as to conduct heat treatment on the interior of the cavity structure. The jet type heat treatment device suitable for the cavity structure with the large length-diameter ratio and the large wall thickness is simple in structure and ingenious in design, cooling liquid is brought into the cavity structure for heat treatment in the mode that the jet pipe is inserted into the cavity structure, and the heat treatment problem of internal materials of components with the large length-diameter ratio and the large wall thickness is effectively solved.

Description

Technical Field

[0001] The utility model relates to the field of casting heat treatment, in particular to a jet type heat treatment device suitable for a cavity structure with a large aspect ratio and thick wall. Background Art

[0002] At present, the casting process is used to obtain cavity structures with large aspect ratios and thick walls. It mainly uses high-temperature alloy solutions to flow and form in the mold and improve the structural strength through certain heat treatment processes. In the heat treatment process of the components, it is usually necessary to place the high-temperature structure in the heat treatment liquid to quickly cool the structure to obtain high-strength material properties. However, when carrying out the material heat treatment process for cavity structures with large aspect ratios and thick walls, the main problems are that the heat treatment liquid is difficult to effectively enter the cavity and the wall thickness is too large to be effectively heat treated, resulting in low heat treatment quality of the material inside the cavity, which in turn affects the strength and use of the structure. This phenomenon is particularly obvious for structures that are closed at one end. There are two main reasons for this phenomenon:

[0003] On the one hand, for the heat treatment process of high-temperature objects, boiling will occur when the heat treatment liquid contacts the wall of the high-temperature object, which reduces the heat treatment efficiency. This makes the heat treatment thickness of the high-temperature object have an upper limit. Boiling heat transfer is a form of convective heat transfer in which the liquid contacts the high-temperature wall and generates steam to take away the heat of the object. Figure 1As shown in the figure, during heat exchange, four heat exchange regions will appear on the wall of the high-temperature object: natural convection zone, nucleate boiling zone, transition boiling zone, and stable transient boiling. When the temperature difference is small, the heat exchange between the high-temperature object and the coolant belongs to natural convection. When the surface temperature of the object is slightly higher than the saturation temperature, bubbles are generated at the interface between the object wall and the cooling medium, and the nucleate boiling heat exchange stage begins. In this stage, as the temperature difference further increases, the heat transfer coefficient and heat flux density on the surface of the high-temperature object increase rapidly, and heat dissipation is mainly achieved through heat conduction. When the temperature difference continues to increase, the heat exchange enters the transition boiling stage. In this stage, the heat flux density decreases instead of increasing. The reason is that too many bubbles form at the interface between the object wall and the cooling medium, forming a gas film on the interface, which hinders the heat transfer from the hot surface to the liquid. When the temperature difference increases further, the heat exchange enters the stable transient boiling stage. In this stage, the interface is completely covered with a stable vapor film, the heat transfer coefficient is very small, and heat dissipation is mainly achieved through liquid film conduction. General water cooling will form a layer of steam film at the contact interface between the high-temperature object and the coolant. The object transfers heat to the coolant through the steam film, which is an order of magnitude lower than the heat transfer coefficient of direct contact between the high-temperature object and the coolant. Therefore, the presence of a large area of ​​steam film seriously affects the heat transfer efficiency. This situation is more significant for the heat treatment of large aspect ratio cavity structures. During heat treatment, due to the relatively small internal cavity of the large aspect ratio component, a large number of bubbles will form on the surface of the material during heat treatment, resulting in insufficient heat treatment of the material inside the cavity, which in turn affects the strength of the material after heat treatment. In particular, for structures with one end closed, it is even more difficult for the heat treatment liquid to effectively enter the closed end of the large aspect ratio structure. The material at this end is insufficiently heat treated, which can easily cause defects inside the material.

[0004] On the other hand, when using the traditional cooling pool cooling heat treatment process for thick-walled cavity materials, the effective heat treatment part is mostly the surface material of the cavity structure, and the heat treatment thickness is limited. In particular, the thickness of the effective heat treatment material is extremely limited due to the difficulty of the heat treatment liquid to enter the inner surface of the cavity (only the superficial surface material can meet the heat treatment process's material processing requirements). Therefore, it is difficult for the current heat treatment process to perform high-quality heat treatment on cavity structures with large aspect ratios and thick walls. In addition, if it is a multi-layer cavity structure, such as Figure 2 As shown, the material processing of the intermediate structure is also difficult to meet the relevant heat treatment process requirements. Therefore, it is urgent to design a jet heat treatment device suitable for large aspect ratio and thick wall cavity structure to solve the above problems. Utility Model Content

[0005] The utility model provides a jet-type heat treatment device suitable for cavity structures with large aspect ratios and thick walls, which has the effect of spraying cooling medium onto the inner surface of the cavity to cool the cavity structure with large aspect ratios and thick walls. The specific technical solution is as follows:

[0006] A jet heat treatment device suitable for cavity structures with large aspect ratios and thick walls, which includes a placement table, on which the cavity structure to be heat treated can be placed and fixed, and a jet device is provided at one end of the placement table. The jet device includes multiple jet tubes, each of which is provided with a spray hole. The jet tube can be inserted into the interior of the cavity structure. The jet tube is connected to a high-pressure jet pump, which provides power for the coolant required for heat treatment and can spray it from the spray hole on the jet tube to perform heat treatment on the interior of the cavity structure.

[0007] Furthermore, a plurality of groups of injection holes are arranged at intervals on the surface of the jet tube, each group of injection holes has four injection holes, and the angle between two adjacent injection holes in the same group is 90 degrees.

[0008] Furthermore, the jet device includes a moving platform, a first support frame is provided on the moving platform, the jet tube is provided on the first support frame, and the moving platform can drive the jet tube to move horizontally as a whole.

[0009] Furthermore, a second support frame is provided at the end of the placement table, and the second support frame can provide support and guidance for the jet tube.

[0010] Furthermore, one end of the jet tube close to the mobile station is connected to the infusion tube. The infusion tube is annular and has a liquid inlet on both sides. The infusion tube is connected to a high-pressure jet pump through the two liquid inlets.

[0011] Furthermore, a spray speed regulating device is connected to the jet tube, and the spray speed regulating device can adjust the flow rate and speed of the coolant sprayed from the spray hole of the jet tube.

[0012] Furthermore, the spray speed adjustment device includes an adjusting rod, which is inserted into the inside of the jet tube. An adjusting baffle is provided on the adjusting rod, which conflicts with the inner wall of the jet tube. There are multiple adjusting baffles and their positions correspond to the spray holes. Rotating the adjusting rod can change the size of the water outlet cross-section of the spray hole.

[0013] Furthermore, the regulating rod is connected to the regulating mechanism, and the regulating mechanism can drive multiple regulating rods to rotate synchronously to simultaneously regulate the flow rate and speed of the coolant in all the injection ports.

[0014] Furthermore, the end of the jet tube inserted into the cavity structure is arc-shaped, and a plurality of jet holes are axially inclinedly arranged on the arc surface.

[0015] Furthermore, a clamping and positioning assembly is provided on the placement table, and the clamping and positioning assembly can position and clamp the cavity structure placed on the placement table.

[0016] The utility model is suitable for the jet heat treatment device of the cavity structure with large aspect ratio and thick wall, with simple structure and ingenious design. By inserting the jet tube into the cavity structure, the coolant is brought into the cavity structure for heat treatment, thereby overcoming the unfavorable factor in the traditional heat exchange theory that the air film between the heat treatment liquid and the wall of the high-temperature object affects the heat treatment effect, and effectively solves the heat treatment problem of the internal materials of the components with large aspect ratio and thick wall.

[0017] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0019] Figure 1 is the relationship diagram between heat flux and superheat temperature difference;

[0020] Figure 2 It is a cavity structure with large aspect ratio and thick wall;

[0021] Figure 3 This is a three-dimensional diagram of the jet heat treatment device of the utility model suitable for cavity structures with large aspect ratio and thick wall;

[0022] Figure 4 This is a schematic diagram of the jet tube of the jet heat treatment device of the present invention, which is suitable for a cavity structure with a large aspect ratio and thick wall, being ready for insertion;

[0023] Figure 5 This is a schematic diagram of the jet tube of the jet heat treatment device of the present invention, which is suitable for a cavity structure with a large aspect ratio and thick wall, after being inserted;

[0024] Figure 6 This is a schematic structural diagram of the jet hole of the jet tube of the jet type heat treatment device suitable for a cavity structure with a large aspect ratio and thick wall in the present invention;

[0025] Figure 7 This is a structural schematic diagram of the jet tube and regulating device of the jet type heat treatment device suitable for a cavity structure with a large aspect ratio and thick wall. DETAILED DESCRIPTION

[0026] In order to better understand the purpose, function and specific design scheme of the present invention, the following is a further detailed description of the jet heat treatment device of the present invention suitable for large aspect ratio and thick wall cavity structure with reference to the accompanying drawings.

[0027] like Figure 3-7 As shown, the jet heat treatment device of the utility model, which is suitable for cavity structures with large aspect ratio and wall thickness, includes a placing table 1. The cavity structure 3 to be heat treated can be placed on the placing table 1 and fixed. A jet device 2 is provided at one end of the placing table 1. The jet device 2 includes a plurality of jet tubes 21. The jet tubes 21 are provided with injection holes 22. The jet tubes 21 can be inserted into the interior of the cavity structure 3. The jet tubes 21 are connected to a high-pressure jet pump. The high-pressure jet pump provides power for the coolant required for heat treatment and can be ejected from the injection holes 22 on the jet tubes 21 to perform heat treatment on the interior of the cavity structure 3.

[0028] Specifically, the surface of the jet tube 21 is provided with multiple groups of injection holes 22, with a spacing of 5 to 10 cm between adjacent groups of injection holes 22. Each group of injection holes 22 consists of four injection holes, and the angle between adjacent injection holes 22 in the same group is 90 degrees. The main purpose of the coolant is to penetrate the air film and dissipate heat evenly. The material of the jet tube 21 can be ceramic or other high-temperature resistant materials. Preferably, the outer surface of the jet tube 21 is provided with a marking scale, and the scale value can be used to determine the length of the jet tube 21 that penetrates into the cavity structure 3.

[0029] The jet device 2 of this embodiment further includes a movable platform 4, on which a first support frame 41 is disposed. The jet tube 21 is disposed on the first support frame 41. The movable platform 4 can drive the jet tube 21 to move horizontally as a whole, thereby facilitating the insertion of the jet tube 21 into the interior of the cavity structure 3 on the placement platform 1. Preferably, a second support frame 11 is disposed at the end of the placement platform 1. The second support frame 11 can provide support and guidance for the jet tube 21, thereby ensuring stable and reliable insertion of the jet tube 21 into the interior of the cavity structure 3 on the placement platform 1.

[0030] One end of the jet tube 21 close to the movable platform 4 is connected to the liquid infusion tube 24. The liquid infusion tube 24 is annular and has a liquid inlet 25 on both sides. The liquid infusion tube 24 is connected to a high-pressure jet pump through the two liquid inlets 25. While increasing the coolant pressure in the jet tube 21, it can also make the pressure in the jet tube 21 at different positions more uniform.

[0031] like Figure 4 and Figure 7As shown, a spray rate adjustment device 5 is connected to the jet tube 21. The spray rate adjustment device 5 can adjust the flow rate and speed of the coolant sprayed from the spray hole 22 of the jet tube 21. The spray rate adjustment device 5 includes an adjustment rod 51, which is inserted into the jet tube 21 and is provided with an adjustment baffle 52. The adjustment baffle 52 contacts the inner wall of the jet tube 21. There are multiple adjustment baffles 52, and their positions correspond to the spray holes 22. Rotating the adjustment rod 51 can change the size of the water outlet cross-section of the spray hole 22, thereby changing the flow rate and speed of the coolant.

[0032] The adjustment rods 51 are connected to an adjustment mechanism 53, which is fixed to the movable platform 4. The adjustment mechanism 53 can drive multiple adjustment rods 51 to rotate synchronously, thereby simultaneously adjusting the flow rate and speed of the coolant at all injection ports. In this embodiment, the adjustment mechanism 53 is a gear train structure, including an adjustment motor 54 connected to a reducer. The adjustment motor 54 and the reducer are fixed to the movable platform 4. The reducer is connected to the driving gear of the gear train. The driving gear drives the rotation of each driven gear, thereby driving the adjustment rods 51 in each jet tube 21 to rotate synchronously, thereby adjusting the flow rate and speed of the coolant at the injection port 22.

[0033] The maximum injection velocity of the coolant is designed to be able to effectively penetrate the air film formed at the interface between the object wall and the cooling medium due to the high temperature difference. The collision pressure threshold for penetrating the air film is P0. When the speed of the coolant ejected from the inside of the jet tube 21 is u, the pressure value generated by the coolant can be calculated according to the Bernoulli equation of fluid mechanics according to formula (1):

[0034] P=0.5ρu 2 (1)

[0035] Where P is the coolant collision pressure, ρ is the coolant density, and u is the coolant injection velocity.

[0036] When formula (2) is satisfied, the coolant ejected from the jet tube 21 can begin to penetrate the air film formed at the interface between the object wall and the cooling medium due to the excessive temperature difference.

[0037] P=P0 (2)

[0038] According to formulas (1) and (2), it can be deduced that the minimum speed at which the coolant ejected from the multi-stage spray rod can penetrate the air film formed at the interface between the object wall and the cooling medium due to the high temperature difference is

[0039]

[0040] The high-pressure jet pump can use this speed as the minimum speed for breaking the film and adjust the cooling liquid speed through the injection speed regulating device 5.

[0041] It is worth noting that, if Figure 6 As shown, the end of the jet tube 21 inserted into the cavity structure 3 is arc-shaped, that is, the end of the jet tube 21 away from the moving platform 4 is arc-shaped, and multiple jet holes 23 are axially inclined on the arc surface. The coolant ejected by the jet hole 23 not only penetrates the air film and evenly dissipates heat, but also accelerates the flow of the coolant inside the cavity structure 3. Its main effect on accelerating the flow of the coolant can be quantitatively described by the following formula. When the injection speed of the coolant is u, the reverse pressure P1 generated in the axial direction can be quantitatively expressed as

[0042] P1=Pcosθ (4)

[0043] When the cavity cross-sectional area is S, the thrust generated by the coolant injection is

[0044] F=P1×S (5)

[0045] When the mass of the coolant in the cavity is M, the acceleration caused by the injection of the heat treatment liquid is

[0046] a=F / M (6)

[0047] On this basis, the speed requirement of the circulation flow of the cooling liquid in the heat treatment process can be further met by adjusting the injection speed of the heat treatment liquid.

[0048] The high-pressure jet pump of this embodiment can set the injection process according to the required injection speed, and a mature industrial product can be selected for the high-pressure jet pump.

[0049] like Figure 3 As shown, a clamping and positioning assembly 6 is provided on the placement table 1. The clamping and positioning assembly 6 can position and clamp the cavity structure 3 placed on the placement table 1. The clamping and positioning assembly 6 includes a positioning plate 61. The positioning plate 61 is vertically movably provided above both sides of the placement table 1. The positioning plate 61 is connected to a positioning drive assembly. The positioning drive assembly can drive the positioning plate 61 to move so that the positioning plate 61 conflicts with the cavity structure 3 and clamps the cavity structure 3. The drive assembly can be a pneumatic cylinder or an electric cylinder. It can be understood that by pushing the positioning plates 61 on both sides, the cavity structure 3 can be placed in the center of the placement table 1 to facilitate the insertion of the jet tube 21. Preferably, a guide plate 62 is connected above the positioning plate 61. The guide plate 62 is tilted toward the outside of the two sides of the placement table 1, thereby providing a guiding function when the cavity structure 3 is placed.

[0050] Preferably, the placement platform 1 includes a liftable lifting platform 12, the upper surface of the lifting platform 12 is used to place the cavity structure 3, and the lower surface of the lifting platform 12 is connected to a lifting mechanism, which can drive the lifting platform 12 to move up and down, thereby adjusting the height of the cavity structure 3 to be aligned with the jet tube 21. The lifting mechanism can be a jack or the like.

[0051] The use process of the jet heat treatment device of the utility model, which is suitable for cavity structures with large aspect ratio and thick wall, is as follows:

[0052] (1) Determine the type of heat treatment liquid (air cooling, water cooling, oil cooling, etc.), the heat treatment process flow, etc. based on the basic properties of the cavity structure 3 to be heat treated, the material property requirements after heat treatment, and other information.

[0053] (2) According to the initial heat treatment environment, the basic properties of the cavity structure 3 to be heat treated, the material property requirements after heat treatment, and other conditions, the membrane rupture pressure and the injection liquid flow rate of the component heat treatment process are calculated and determined, and the injection liquid injection process is determined.

[0054] (3) Insert the jet tube 21 into the cavity, turn on the high-pressure jet pump, and fill the jet tube 21 with coolant. If the film needs to be broken due to temperature difference, first adjust the flow rate of the jet liquid until it meets the requirements. Wait until the inner surface temperature of the cavity structure 3 drops to a point where no air film is generated. Then, control the baffle 52 again to allow the coolant to be sprayed onto the inner surface of the cavity structure 3 to achieve heat dissipation. Then, further adjust the injection speed of the jet liquid through the injection speed adjustment device 5 according to the process conditions of the required heat treatment.

[0055] (4) After the heat treatment of the cavity structure 3 is completed, the high-pressure jet pump is first turned off, and then the jet tube 21 is withdrawn, thereby completing the heat treatment of the component with a large aspect ratio and thick wall.

[0056] The utility model is suitable for the jet heat treatment device of the cavity structure with large aspect ratio and thick wall, with simple structure and ingenious design. By inserting the jet tube into the cavity structure, the coolant is brought into the cavity structure for heat treatment, thereby overcoming the unfavorable factor in the traditional heat exchange theory that the air film between the heat treatment liquid and the wall of the high-temperature object affects the heat treatment effect, and effectively solves the heat treatment problem of the internal materials of the components with large aspect ratio and thick wall.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A jet heat treatment device suitable for large aspect ratio and thick wall cavity structure, characterized in that: It includes a placement table, on which the cavity structure to be heat treated can be placed and fixed. A jet device is provided at one end of the placement table. The jet device includes multiple jet tubes. The jet tubes are provided with injection holes. The jet tubes can be inserted into the interior of the cavity structure. The jet tubes are connected to a high-pressure jet pump. The high-pressure jet pump provides power for the coolant required for heat treatment and can spray it from the injection holes on the jet tubes to perform heat treatment on the interior of the cavity structure.

2. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 1, characterized in that: A plurality of groups of injection holes are arranged at intervals on the surface of the jet tube, each group of injection holes consists of four injection holes, and the angle between two adjacent injection holes in the same group is 90 degrees.

3. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 1, characterized in that: The jet device comprises a moving platform, a first supporting frame is arranged on the moving platform, the jet tube is arranged on the first supporting frame, and the moving platform can drive the jet tube to move horizontally as a whole.

4. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 3, characterized in that: A second support frame is provided at the end of the placement platform, and the second support frame can provide support and guidance for the jet tube.

5. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 3, characterized in that: The end of the jet tube close to the mobile platform is connected to the infusion tube. The infusion tube is annular and has a liquid inlet on both sides. The infusion tube is connected to a high-pressure jet pump through the two liquid inlets.

6. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 1, characterized in that: The jet pipe is connected with a spray speed regulating device, which can adjust the flow rate and speed of the coolant sprayed from the spray hole of the jet pipe.

7. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 6, characterized in that: The spray speed adjustment device includes an adjusting rod, which is inserted into the inside of the jet tube. An adjusting baffle is provided on the adjusting rod, which conflicts with the inner wall of the jet tube. There are multiple adjusting baffles and their positions correspond to the spray holes. Rotating the adjusting rod can change the size of the water outlet cross-section of the spray hole.

8. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 7, characterized in that: The regulating rod is connected to the regulating mechanism, and the regulating mechanism can drive multiple regulating rods to rotate synchronously to simultaneously regulate the flow rate and speed of the coolant of all the injection ports.

9. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 1, characterized in that: The end portion of the jet tube inserted into the cavity structure is arc-shaped, and a plurality of jet holes are axially inclinedly arranged on the arc surface.

10. The jet heat treatment device suitable for cavity structures with large aspect ratio and thick wall according to claim 1, characterized in that: The placement table is provided with a clamping and positioning component, which can position and clamp the cavity structure placed on the placement table.

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