A pressure spring tube and a manufacturing method thereof

Abstract

The present application provides a pressure spring tube and a manufacturing method thereof. The pressure spring tube is a hollow tube, and the material can be selected from stainless steel or elastic alloy. The manufacturing method steps are blanking, cleaning and drying, solution heat treatment, cleaning and drying, winding and forming, cleaning and drying, end face turning, cleaning and drying, quenching, cleaning and drying, tempering, cleaning and drying, hardness and grain size detection; the present invention provides a sensitive element that can withstand large pressure and large displacement, and at the same time proposes its specific manufacturing method.

Description

Technical Field

[0001] The present application belongs to the technical field of aviation pressure instruments, and specifically relates to a pressure spring tube and a manufacturing method thereof. Background Art

[0002] In the field of aviation pressure instruments, most of the sensitive elements used in pressure gauges on the market are C-type end-capped tubes. However, due to the limitations of their characteristics, the displacement of C-type end-capped tubes becomes smaller when they sense greater pressure, making debugging more difficult. Therefore, it is necessary to design a sensitive element that can withstand high pressure and has a larger displacement, and at the same time propose a manufacturing method. Summary of the invention

[0003] Purpose of the invention: With the development of aircraft pressure systems, hydraulic systems have been upgraded from 21MPa to 35MPa. The increase in system pressure has put forward new requirements for the matching pressure gauges, requiring the pressure gauges to be able to withstand greater pressures. The current sensitive element - the C-type end-wrapped tube can no longer meet the new requirements. In order to withstand high pressures, the wall thickness of the C-type end-wrapped tube is increased, which brings the disadvantage of smaller displacement. The smaller displacement makes it more difficult to debug the C-type end-wrapped tube pressure gauge. In order to solve the problem of withstanding high pressure and large displacement at the same time, a pressure spring tube and a manufacturing method thereof are provided.

[0004] In a first aspect, the present application provides a method for manufacturing a pressure spring tube, the method comprising:

[0005] Carrying out material cutting process on the central control pipe material to obtain a blank, and then cleaning and drying the blank;

[0006] Performing solution heat treatment, cleaning and drying on the blank;

[0007] The blank is subjected to a winding forming process to obtain an initial pressure spring tube, and the initial pressure spring tube is cleaned and dried;

[0008] Carrying end surface treatment, cleaning and drying the initial pressure spring tube;

[0009] The initial pressure spring tube is quenched, cleaned and dried;

[0010] Then the initial pressure spring tube is tempered, cleaned and dried to obtain a final pressure spring tube;

[0011] The final pressure spring tube is subjected to hardness and grain size testing.

[0012] Preferably, the purpose of the solution heat treatment is to reduce the material hardness of the hollow tube, and the specific parameters are temperature 850-900°C, holding time 60-90min, cooling method air cooling at 150°C with the furnace, and vacuum degree of the heat treatment furnace 1.33×10-2Pa.

[0013] Preferably, the purpose of cleaning and drying is to clean the grease on the inner and outer surfaces of the central control pipe. The specific parameters are cleaning for 30-60 minutes, using acetone as the cleaning agent, drying at 100° C., and drying time for 60 minutes.

[0014] Preferably, the purpose of blanking is to cut according to the designed length.

[0015] Preferably, the purpose of winding is to wind the straight hollow tube into a spiral shape. The central control tube is wound by a customized winding device and has a spiral shape with 2.5 turns. Pressure inlets and outlets are left in the upper and lower turns.

[0016] Preferably, the end face is cut by a lathe, and the length is based on design requirements.

[0017] Preferably, the purpose of quenching is to increase the material hardness of the central control pipe, and the specific parameters are temperature 1000-1100° C., holding time 30 minutes, and cooling method oil cooling.

[0018] Preferably, the purpose of tempering is to remove the excess stress of the central control pipe, and the specific parameters are a temperature of 300-350°C, a holding time of 60-90min, and a cooling method of air cooling at 150°C in the furnace.

[0019] Preferably, the purpose of hardness and grain size testing is to check whether the hardness and grain size of the central control pipe material meet the design requirements. The specific parameters are that the hardness is not less than HV400 and the grain size is not less than grade 7.

[0020] In a second aspect, the present application also provides a pressure spring tube, which is manufactured by the above method.

[0021] This application has the following technical effects:

[0022] The present invention proposes a new type of pressure sensitive element - pressure spring tube. As mentioned above, due to the increase in pressure of the aircraft pressure system, the pressure resistance requirement of the matching pressure gauge increases. When the pressure increases, the displacement of the sensitive element for sensing the pressure - the C-type wrapped end tube becomes smaller, which makes it difficult to debug the pressure gauge. In order to solve the problem of large displacement while withstanding high pressure, a pressure spring tube is proposed, which not only has enhanced pressure resistance, but also has increased displacement, making it easy to debug the pressure gauge. In addition, the present invention proposes a method for manufacturing the pressure spring tube and a practical process method, which has high practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of a pressure spring tube provided by the present application;

[0024] Figure 2 This is a schematic diagram of the central control pipe material before winding;

[0025] Figure 3 This is a schematic diagram after winding is completed. DETAILED DESCRIPTION

[0026] It should be noted that with the development of aircraft pressure systems, the hydraulic system has been upgraded from 21MPa to 35MPa. The increase in system pressure has put forward new requirements for the matching pressure gauges, requiring the pressure gauges to be able to withstand greater pressures. The current sensitive element - the C-type end-wrapped tube can no longer meet the new requirements. In order to withstand high pressures, the wall thickness of the C-type end-wrapped tube is increased, which brings the disadvantage of smaller displacement. The smaller displacement makes it more difficult to debug the C-type end-wrapped tube pressure gauge. In order to solve the problem of withstanding high pressure and large displacement at the same time, a pressure spring tube and a manufacturing method thereof are provided.

[0027] Combine the following Figure 1-Figure 3 The present invention is further described with reference to the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0028] See also Figure 1 and Figure 3 The schematic diagram of the pressure spring tube shown in FIG. Figure 1 It is the central control tube material of the pressure spring tube, and its material is stainless steel or elastic alloy.

[0029] In the embodiment of the present application, the specific manufacturing process and method of the pressure spring tube are as follows:

[0030] Among them, the manufacturing process: cutting, cleaning and drying, solution heat treatment, cleaning and drying, winding and forming, cleaning and drying, end face turning, cleaning and drying, quenching, cleaning and drying, tempering, cleaning and drying, hardness and grain size testing.

[0031] The present invention proposes a new type of pressure sensitive element - pressure spring tube. As mentioned above, due to the increase in pressure of the aircraft pressure system, the pressure resistance requirement of the matching pressure gauge increases. When the pressure increases, the displacement of the sensitive element for sensing the pressure - the C-type wrapped end tube becomes smaller, which makes it difficult to debug the pressure gauge. In order to solve the problem of large displacement while withstanding high pressure, a pressure spring tube is proposed, which not only has enhanced pressure resistance, but also has increased displacement, making it easy to debug the pressure gauge. In addition, the present invention proposes a method for manufacturing the pressure spring tube and a practical process method, which has high practical application value.

[0032] Among them, cutting, the purpose of cutting is to cut according to the designed length.

[0033] Among them, cleaning and drying are aimed at cleaning the grease on the inner and outer surfaces of the central control pipe. The specific parameters are cleaning in the cleaning machine for 30-60 minutes, the cleaning machine uses acetone, the drying temperature is 100°C, and the time is 60 minutes.

[0034] Among them, the purpose of solution heat treatment is to reduce the hardness of the hollow tube material to facilitate subsequent machining. The solution heat treatment uses a vacuum furnace, and the temperature of the vacuum furnace is set at 850-900 ° C. Then put the cleaned blanks into the vacuum furnace. Be careful not to stack them together, but spread them out. Then, vacuumize and keep warm for 60-90 minutes. The cooling method is to open the furnace and take out the blanks when the furnace is cooled to 150 ° C. The vacuum degree of the heat treatment furnace is 1.33×10 -2 Pa.

[0035] Among them, the purpose of winding and forming is to wind the straight hollow tube into a spiral shape. The central control tube is wound and formed by customized winding equipment. The shape is spiral, the number of winding turns is 2.5 turns, and pressure inlets and outlets are left in the upper and lower turns.

[0036] Among them, the end face is turned and the end face is cut by a lathe, and the length is based on the design requirements.

[0037] Among them, quenching, the purpose of quenching is to improve the material hardness of the central control tube. The quenching adopts a vacuum oil catalytic furnace, and the temperature of the oil quenching furnace is set to 1000-1100℃. Then put the cleaned initial pressure spring tube into the vacuum furnace. Be careful not to stack them together, but spread them out. After 30 minutes of insulation time, oil cooling is carried out.

[0038] Among them, tempering, the purpose of tempering is to remove the excess stress of the central control tube. The tempering adopts a vacuum furnace, and the temperature of the vacuum furnace is set at 300-350℃. Then put the cleaned initial pressure spring tube into the vacuum furnace. Be careful not to stack them together, but spread them out. Then vacuumize and keep them warm for 60-90min. Cool down with the furnace to 150℃ and open the furnace to take out the initial pressure spring tube. The vacuum degree of the heat treatment furnace is 1.33×10 -2 Pa.

[0039] Among them, the hardness and grain size test, the purpose of hardness and grain size test is to check whether the hardness and grain size of the central control pipe material meet the design requirements. The specific parameters are hardness not less than HV400, and grain size requirement not less than level 7.

[0040] The present invention proposes a new type of pressure sensitive element - pressure spring tube. As mentioned above, due to the increase in pressure of the aircraft pressure system, the pressure resistance requirement of the matching pressure gauge increases. When the pressure increases, the displacement of the sensitive element for sensing the pressure - the C-type wrapped end tube becomes smaller, which makes it difficult to debug the pressure gauge. In order to solve the problem of large displacement while withstanding high pressure, a pressure spring tube is proposed, which not only has enhanced pressure resistance, but also has increased displacement, making it easy to debug the pressure gauge. In addition, the present invention proposes a method for manufacturing the pressure spring tube and a practical process method, which has high practical application value.

[0041] In other embodiments of the present application, the present application provides a pressure spring tube and a manufacturing method thereof. The pressure spring tube is a hollow tube, and the material can be selected from stainless steel or elastic alloy. The manufacturing method steps are blanking, cleaning and drying, solid solution heat treatment, cleaning and drying, winding and forming, cleaning and drying, end face turning, cleaning and drying, quenching, cleaning and drying, tempering, cleaning and drying, hardness and grain size detection; the present invention provides a sensitive element that can withstand large pressure and large displacement, and at the same time proposes its specific manufacturing method.

Claims

1. A method for manufacturing a pressure spring tube, characterized in that: The method comprises: Carrying out material cutting process on the central control pipe material to obtain a blank, and then cleaning and drying the blank; Performing solution heat treatment, cleaning and drying on the blank; The blank is subjected to a winding forming process to obtain an initial pressure spring tube, and the initial pressure spring tube is cleaned and dried; Carrying end surface treatment, cleaning and drying the initial pressure spring tube; The initial pressure spring tube is quenched, cleaned and dried; Then the initial pressure spring tube is tempered, cleaned and dried to obtain a final pressure spring tube; The final pressure spring tube is subjected to hardness and grain size testing.

2. The method according to claim 1, characterized in that The purpose of solution heat treatment is to reduce the material hardness of the hollow tube. The specific parameters are temperature 850-900℃, holding time 60-90min, cooling method is air cooling at 150℃, and the vacuum degree of the heat treatment furnace is 1.33×10-2Pa.

3. The method according to claim 1, characterized in that: The purpose of cleaning and drying is to clean the grease on the inner and outer surfaces of the central control pipe. The specific parameters are cleaning for 30-60 minutes, acetone as the cleaning agent, drying temperature of 100°C, and time of 60 minutes.

4. The method according to claim 1, characterized in that The purpose of cutting is to cut according to the designed length.

5. The method according to claim 1, characterized in that The purpose of winding is to wind a straight hollow tube into a spiral shape. The central control tube is wound by customized winding equipment. The shape is spiral, the number of winding turns is 2.5, and pressure inlets and outlets are left in the upper and lower turns.

6. The method according to claim 1, characterized in that The end face is cut by lathe, and the length is based on the design requirements.

7. The method according to claim 1, characterized in that The purpose of quenching is to improve the material hardness of the central control pipe. The specific parameters are temperature 1000-1100℃, holding time 30min, and cooling method oil cooling.

8. The method according to claim 1, characterized in that The purpose of tempering is to remove the excess stress of the central control tube. The specific parameters are temperature 300-350℃, holding time 60-90min, and cooling method is air cooling at 150℃.

9. The method according to claim 1, characterized in that: The purpose of hardness and grain size testing is to check whether the hardness and grain size of the central control pipe material meet the design requirements. The specific parameters are that the hardness is not less than HV400 and the grain size is not less than level 7.

10. A pressure spring tube, characterized in that: The pressure spring tube is manufactured by the method according to any one of claims 1 to 9.

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