Heat exchanger welding inspection clamp

Abstract

The utility model discloses a welding inspection clamp for a heat exchanger. The welding inspection clamp comprises a mounting bottom plate, a positioning support, a welding mandrel assembly, a reducing sleeve and an inspection mandrel. A plurality of supporting arms extend out of the positioning support in the same direction, the number of the supporting arms is consistent with that of connectors on the heat exchanger, each supporting arm is provided with a mounting hole, and X-axis and Y-axis numerical values in spatial position coordinates of the mounting holes are consistent with X-axis and Y-axis numerical values in spatial position coordinates of the connectors on the heat exchanger. And one end of the reducing sleeve is connected with an upper interface of the heat exchanger, and the other end is connected with the welding mandrel or the inspection mandrel. According to the utility model, the spatial position sizes of all joints of the novel heat exchanger meet the installation requirements, the sealing surfaces of multiple joints are protected in the welding process, and the novel heat exchanger has the function of post-welding detection.

Description

Technical Field

[0001] The utility model relates to a heat exchanger welding inspection fixture, in particular to a fixture structure with the functions of welding positioning and post-weld inspection, thereby ensuring the consistency of the spatial position and size of the heat exchanger interface and guaranteeing interchangeability. Background Art

[0002] Plate-fin heat exchangers have been widely used in aircraft and engine fields. With the upgrading of aircraft and engines, the demand for heat exchangers has also developed towards integrated and high-efficiency new heat exchangers. For example, new heat exchangers are integrated with filters, anti-freezing devices, temperature-sensing valves, pressure-sensing valves, signal devices and other functional components; in new heat exchangers ( Figure 1 ) structure, the channel is built-in, eliminating the traditional heat exchanger ( Figure 2 ) gas hood, which greatly saves space. However, the manufacturing difficulty of this new type of heat exchanger increases accordingly, mainly in the following aspects:

[0003] 1) The new heat exchanger integrates more functional components, and the spatial size has increased from 4 to 6 in traditional heat exchangers to more than ten;

[0004] 2) Due to the large number of integrated components and interfaces, the host has a small operating space during installation and a small adjustment margin. Therefore, the spatial position size of each interface is compressed from the traditional free tolerance (±2.5mm) to ±0.5mm;

[0005] 3) There are many integrated parts and dense welds, and the welding deformation generated during the product welding process is large;

[0006] 4) The joints of integrated functional components mostly adopt quasi-surface sealing, which is prone to bumps and scratches during welding, resulting in poor sealing after installation.

[0007] Therefore, it is necessary to design a welding inspection fixture to ensure that the spatial position dimensions and sealing effect of each interface meet the installation requirements of the new heat exchanger. Summary of the Invention

[0008] In response to the problems existing in the background technology, the utility model aims to provide a heat exchanger welding inspection fixture to ensure that the spatial position dimensions of all joints of the new heat exchanger meet the installation requirements, ensure that the sealing surfaces of multiple joints are protected during the welding process, and have the function of post-weld detection.

[0009] In order to solve the above problems, the present invention adopts the following technical solutions:

[0010] Heat exchanger welding inspection fixture, including:

[0011] An installation base plate, wherein the upper end surface of the installation base plate forms an installation reference surface;

[0012] A positioning support, the positioning support being vertically and detachably connected to the upper end surface of the mounting base, and having a plurality of support arms extending from the positioning support in the same side direction at different heights from the mounting base, the number of the support arms being consistent with the number of interfaces on the heat exchanger, each support arm having a mounting hole, and the X-axis and Y-axis values ​​of the spatial position coordinates of the mounting hole being consistent with the X-axis and Y-axis values ​​of the spatial position coordinates of the interface on the heat exchanger;

[0013] The welding mandrel and the inspection mandrel are inserted into the mounting hole of the positioning support during welding, and the inspection mandrel is inserted into the mounting hole of the positioning support when welding is completed and inspection is performed. An annular protrusion is coaxially provided on the welding mandrel and the inspection mandrel;

[0014] An adapter sleeve, one end of which is connected to the upper interface of the heat exchanger, and the other end of which is connected to the welding core shaft or the inspection core shaft.

[0015] Furthermore, the flatness of the upper end surface of the mounting base plate is less than or equal to 0.01.

[0016] Furthermore, the deviation between the X-axis and Y-axis values ​​in the spatial position coordinates of the mounting hole and the X-axis and Y-axis values ​​in the spatial position coordinates of the interface on the heat exchanger is less than or equal to 0.01 mm.

[0017] Furthermore, the Z-axis values ​​of the spatial position coordinates of the mounting holes are all greater than the Z-axis values ​​of the spatial position coordinates of the interface on the heat exchanger.

[0018] As a solution, the length of the matching surface between the welding mandrel and the inspection mandrel and the inner wall of the mounting hole is greater than the hole depth of the mounting hole.

[0019] As a solution, a locking screw is further provided on the support arm, and the end of the locking screw is pressed against the surface of the welding core shaft or the inspection core shaft.

[0020] Furthermore, the fitting clearance between the welding mandrel and the inspection mandrel and the mounting hole is less than or equal to 0.05 mm.

[0021] As a solution, the ends of the welding mandrel and the inspection mandrel are processed with chamfers.

[0022] As a solution, the surface of one end of the adapter sleeve connected to the interface on the heat exchanger is processed with an external thread, and the end connected to the welding core shaft and the inspection core shaft is provided with a blind hole.

[0023] Compared with the prior art, the present invention has the following features:

[0024] (1) The utility model is easy to disassemble during welding and inspection, and the welding mandrel and the inspection mandrel are both hole-shaft matched;

[0025] (2) The utility model adopts an adapter sleeve structure to protect the joint of the heat exchanger, and the sealing surface of the joint will not be bumped or scratched during the welding process;

[0026] (3) The present invention adopts a method of processing multiple mounting holes on the positioning support, the spatial positions of which are consistent with the interfaces on the heat exchanger, and the positioning support and the mounting base are detachably connected, so that it can adapt to the welding and inspection of heat exchangers of different specifications. On the other hand, the mounting holes unify the processing datum to ensure the accuracy of welding and inspection, and meet the requirements of the increased number of functional components and spatial position size relationship of the new heat exchanger; (4) The present invention extends the contact surface between the welding mandrel and the inspection mandrel and the mounting hole, further improving the accuracy of welding and inspection. On the other hand, by coaxially arranging annular protrusions on the welding mandrel and the inspection mandrel, and using the end face of the annular protrusion as the welding shrinkage measurement surface, the welding dimensional accuracy is controlled;

[0027] (5) The present invention solves the problem of narrowing the spatial position tolerance of each interface by limiting the flatness of the mounting base, the deviation value of the spatial position coordinates of the mounting hole and the interface on the heat exchanger, and the matching clearance between the welding mandrel and the inspection mandrel and the mounting hole;

[0028] (6) The positioning support of the present invention is an integral structure, and its rigidity is controlled by thickness and heat treatment, so as to adapt to the welding deformation problem caused by the large number of integrated parts and dense welds. The multiple arms on the positioning support all extend from the positioning support in the same direction, which facilitates welding and inspection operations and avoids interference problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a three-dimensional diagram of the structure of the new heat exchanger in the present utility model;

[0030] Figure 2 This is a three-dimensional diagram of the traditional heat exchanger structure;

[0031] Figure 3 This is a structural diagram of the new heat exchanger welding inspection fixture in this utility model;

[0032] In the figure: 1-installation base plate; 2-positioning support; 3-welding mandrel; 4-adapter sleeve; 5-inspection mandrel. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. However, it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to common technical knowledge and customary means in the field are included in the scope of the present invention.

[0034] like Figure 3 As shown, the novel heat exchanger welding inspection fixture includes: a mounting base plate 1, a positioning support 2, a welding core shaft assembly 3, an adapter sleeve 4 and an inspection core shaft 5.

[0035] 1. Mounting base plate 1: It is the mounting base and rigid body of the new heat exchanger welding inspection fixture. It is made of 30-50mm thick steel plate and stress-relief annealing before finishing to ensure that the flatness of the mounting surface is no greater than 0.01.

[0036] 2. Positioning support 2: This component is the key component to ensure the spatial position size of each interface. It is required that the spatial position size deviation of the mounting holes corresponding to each inspection core shaft 3 on the component is no more than 0.01mm, and the fitting clearance between each mounting hole and the welding core shaft 3 and the inspection core shaft 4 is no more than 0.05mm; the material is processed with steel plate or steel rod to ensure rigidity; the thickness of each mounting hole is required to be between 30 and 50mm; quenching and tempering treatment is performed before fine machining, and then CNC fine machining is adopted, with a 0.05mm allowance for the aperture, and paired grinding is adopted after fine machining to ensure that the fitting clearance with the welding core shaft 3 and the inspection core shaft 4 is no more than 0.05mm; the mounting holes are all designed to be concentrated in the same direction (side) of the same positioning support 2, which is convenient for operation and tooling manufacturing, with good integrity, and at the same time, the strength of the positioning support 2 is good;

[0037] 3. Welding mandrel 3: Made of steel rod. The length of the mating surface with the positioning support 2 is required to be 15 to 25 mm longer than the thickness of the mounting hole of the positioning support 2 (that is, the length of the outer cylindrical surface of the welding mandrel 3 is longer than the inner cylindrical surface of the mounting hole, so the guide cylindrical surface is enlarged at the mandrel head. Since the length of the inner cylindrical surface of the mounting hole is equal to the thickness of the support arm at the location of the mounting hole, the thickness value at this location is equivalent to the length of the inner cylindrical surface of the mounting hole). The end is processed with a guide angle of 10 to 15 degrees; quenching and tempering treatment is performed before fine machining, and grinding is used after fine machining to ensure that the gap between the welding mandrel 3 and the mounting hole of the positioning support 2 is not greater than 0.05 mm.

[0038] 4. Adapter sleeve 4: This is primarily used to prevent the steel welding mandrel 3 and inspection mandrel 5 from directly contacting the aluminum heat exchanger joint, preventing the aluminum heat exchanger joint from being scratched, squeezed, or deformed during repeated assembly and disassembly. The adapter sleeve 4 is typically made from brass rod, with one end having threads matching the heat exchanger joint (with an H6 thread tolerance) for securing the joint during assembly welding. The other end has a hole (with an H7 hole tolerance) for positioning the welding mandrel 3 and inspecting the inspection mandrel 5.

[0039] 5. Inspection mandrel 5: The inspection mandrel 5 is used to check the relative position and size of each joint after welding (the specific method is to replace the welding mandrel 3 with the corresponding inspection mandrel 5 after welding. The inspection mandrel 5 can be inserted into the hole on the adapter sleeve 4, and the gap with the end face of the positioning support 2 is not more than 0.5mm to be qualified). It is made of steel rod. It is required that the length of the mating surface with the positioning support 2 is 15 to 25 mm longer than the thickness of the mounting hole of the positioning support 2 (that is, the length of the outer cylindrical surface of the inspection core shaft 5 is longer than the inner cylindrical surface of the mounting hole, thereby increasing the guide cylindrical surface at the core shaft head. Since the length of the inner cylindrical surface of the mounting hole is equal to the thickness of the support arm at the location of the mounting hole, the thickness value at this location is equivalent to the length of the inner cylindrical surface of the mounting hole), and the end is processed with a guide angle of 10 to 15°; the diameter of the end that cooperates with the adapter sleeve 4 is 0.2 to 0.3 mm smaller than the hole on the adapter sleeve 4; quenching and tempering treatment is performed before fine machining, and grinding is used for matching after fine machining to ensure that the mating clearance between the inspection core shaft 5 and the mounting hole of the positioning support 2 is not greater than 0.05 mm.

[0040] 6. After the above parts are assembled together, they are fixed by means of positioning pins and bolt connectors;

[0041] 7. Use laser marking, three-coordinate measurement and other methods to measure the assembled welding inspection fixture to ensure that the three-dimensional dimensions of the space meet the requirements of the tooling drawings.

[0042] Heat exchanger welding inspection fixture Figure 2 The steps for welding inspection of new heat exchangers include:

[0043] 1. Fix the heat exchanger body to the mounting base 1 of the welding inspection fixture through the holes on the heat exchanger mounting base;

[0044] 2. Fix the heat exchanger joint and adapter sleeve 4 through threaded connection, and test-fit the welding mandrel 3 on the heat exchanger welding inspection fixture. Ensure that there is a gap of 0.5 to 1 mm between the end face of the annular protrusion of the welding mandrel 3 and the surface of the positioning support 2 (the reserved axial welding shrinkage can be adjusted according to the actual size of the part welding seam), and then tighten the locking screw to fix the welding mandrel 3;

[0045] 3. Perform tack welding and welding on the joint and the heat exchanger body on the heat exchanger welding inspection fixture;

[0046] 4. After cooling, replace the welding mandrel 3 with the inspection mandrel 5 and check the relative position and size of the joint. Specifically, the inspection mandrel 5 can be inserted into the hole on the adapter sleeve 4, and the gap between the end face of the annular protrusion of the inspection mandrel 5 and the end face of the positioning support 2 is not greater than 0.5mm to be qualified.

[0047] like Figure 1The figure shows a new type of aluminum alloy heat exchanger. It integrates functional components such as a filter, temperature-sensing valve, pressure-sensing valve, and annunciator. It has three external joints, primarily made of 6061 aluminum alloy. Each joint has a spatial position tolerance of ±0.5mm, and the assembly with the main unit utilizes a 74° conical seal. The following further describes the design, production, and use of the heat exchanger welding inspection fixture, using this new type of heat exchanger as a starting point:

[0048] 1. Mounting base plate 1: Made of 35mm thick 45# steel plate. Stress relief annealing is performed before finishing, and the flatness of the mounting surface is not greater than 0.01mm;

[0049] 2. Positioning support 2: Machined from 45# steel rod. The spatial position dimensional deviation of the holes corresponding to the welding mandrel 3 and the inspection mandrel 5 shall not exceed 0.01mm, and the clearance between each hole and the welding mandrel 3 and the inspection mandrel 5 shall not exceed 0.05mm. The thickness of each mounting hole shall be 40mm. Before finishing, the holes shall be quenched and tempered, and then CNC finished, with a 0.05mm allowance for the hole diameter. After finishing, the holes shall be ground. The clearance between the holes and the welding mandrel 3 and the inspection mandrel 5 shall not exceed 0.05mm.

[0050] 3. Welding mandrel 3: Made from 45# steel bar. The length of the mating surface with the positioning support 2 is 20mm longer than the thickness of the location where the positioning support 2 mounting hole is located, and the end is machined with a 12° guide angle. It is quenched and tempered before finishing and ground after finishing. The gap between the welding mandrel 3 and the positioning support 2 is no more than 0.05mm.

[0051] 4. Adapter sleeve 4: Made of H62 brass rod. The thread tolerance for matching the upper joint of the heat exchanger is h6, and the hole tolerance for matching the welding core shaft 3 is h7.

[0052] 5. Inspection mandrel 5: It is made of 45# steel rod. The length of the mating surface with the positioning support 2 is 20mm longer than the thickness of the mounting hole of the positioning support 2, and the end is processed with a 12° guide angle; the diameter of the end that matches the adapter sleeve 4 is 0.3mm smaller than the hole on the adapter sleeve 4; it is quenched and tempered before fine machining, and the pairing is ground after fine machining to ensure that the clearance between the lower end face of the annular protrusion of the inspection mandrel 5 and the positioning support 2 is not greater than 0.05mm.

[0053] 6. After the above parts are assembled together, they are fixed by means of positioning pins and bolts;

[0054] 7. Use three-coordinate measurement and other methods to measure the assembled welding inspection fixture to ensure that the three-dimensional dimensions of the space meet the requirements of the tooling drawings;

[0055] 8. Fix the heat exchanger body to the mounting base 1 of the qualified welding inspection fixture through the holes on the heat exchanger mounting base;

[0056] 9. Fix the heat exchanger joint and adapter sleeve 4 with threaded connections, and test-fit the welding mandrel 3 on the heat exchanger welding inspection fixture. Ensure that there is a 0.8mm gap between the lower end surface of the annular protrusion of the welding mandrel 3 and the positioning support 2 (reserved axial welding shrinkage), then tighten the locking screw to compress the welding mandrel 3.

[0057] 10. Perform tack welding and welding on the joint and the heat exchanger body on the heat exchanger welding inspection fixture;

[0058] 11. After cooling, replace the welding mandrel 3 with the inspection mandrel 5 and check the relative position and size of the joint to determine whether the result is qualified. The specific steps are: check that the mandrel 5 can be inserted into the adapter sleeve 4, and that the gap between the lower end face of the annular protrusion of the mandrel 5 and the end face of the positioning support 2 is 0.3mm;

[0059] 12. Remove the heat exchanger from the fixture, separate the adapter sleeve 4 from the connector on the product, and check whether the heat exchanger connector has any bumps or scratches;

[0060] 13. Carry out color inspection on the sealing surface of the heat exchanger joint to determine whether it is qualified.

[0061] The above is only one specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. Heat exchanger welding inspection fixture, characterized in that: include: A mounting base plate (1), wherein the upper end surface of the mounting base plate (1) forms a mounting reference surface; A positioning support (2), the positioning support (2) being vertically and detachably connected to the upper end surface of the mounting base plate (1), a plurality of support arms extending from the positioning support (2) in the same side direction and at different heights from the mounting base plate (1), the number of the support arms being consistent with the number of interfaces on the heat exchanger, each support arm being provided with a mounting hole, and the X-axis and Y-axis values ​​in the spatial position coordinates of the mounting hole being consistent with the X-axis and Y-axis values ​​in the spatial position coordinates of the interface on the heat exchanger; A welding mandrel (3) and an inspection mandrel (5), wherein during welding, the welding mandrel (3) is inserted into the mounting hole of the positioning support (2); after welding is completed and inspection is performed, the inspection mandrel (5) is inserted into the mounting hole of the positioning support (2); and an annular protrusion is coaxially arranged on the welding mandrel (3) and the inspection mandrel (5); An adapter sleeve (4), one end of which is connected to an interface on the heat exchanger, and the other end of which is connected to a welding mandrel (3) or an inspection mandrel (5).

2. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The flatness of the upper end surface of the mounting base plate (1) is less than or equal to 0.

01.

3. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The deviation between the X-axis and Y-axis values ​​in the spatial position coordinates of the mounting hole and the X-axis and Y-axis values ​​in the spatial position coordinates of the interface on the heat exchanger is less than or equal to 0.01 mm.

4. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The Z-axis values ​​in the spatial position coordinates of the mounting holes are all greater than the Z-axis values ​​in the spatial position coordinates of the interface on the heat exchanger.

5. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The length of the matching surface between the welding mandrel (3) and the inspection mandrel (5) and the inner wall of the mounting hole is greater than the hole depth of the mounting hole.

6. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The support arm is also provided with a locking screw, the end of which is pressed tightly against the surface of the welding mandrel (3) or the inspection mandrel (5).

7. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The matching clearance between the welding mandrel (3) and the inspection mandrel (5) and the mounting hole is less than or equal to 0.05 mm.

8. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The ends of the welding mandrel (3) and the inspection mandrel (5) are processed with chamfers.

9. The heat exchanger welding inspection fixture according to claim 1, characterized in that: The surface of one end of the adapter sleeve (4) connected to the interface on the heat exchanger is processed with an external thread, and the end connected to the welding mandrel (3) and the inspection mandrel (5) is provided with a blind hole.

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