A method for manufacturing a fuel injection rod with a large long diameter deep hole

Abstract

The present invention belongs to the field of additive manufacturing technology, and specifically relates to a method for manufacturing a spray rod with a long-diameter deep hole. The method comprises the following steps: establishing a three-dimensional model of the spray rod, a support model, and a powder discharge mechanism model to form a printing model; the support model comprises an oblique support model and an interface support model, the interface support model comprising a first interface support model and a second interface support model; the first interface support model is placed between the oblique support and the three-dimensional spray rod model, and the second interface support model is placed between the three-dimensional spray rod model and the powder discharge mechanism model; the oblique surface of the oblique support model is at an angle to the substrate; the printing model is deposited layer by layer on the substrate; vacuum stress relief is performed on the part with the substrate; and post-processing is performed to obtain a formed spray rod. The spray rod is integrally formed, and a new support structure is designed to assist in part growth. The hollow solid structure ensures part formation while saving powder raw materials and facilitating powder removal.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing, and in particular relates to a method for manufacturing a fuel injection rod with a large long diameter deep hole. Background Art

[0002] The fuel injection rod is one of the important parts of the afterburner. Figure 1 and Figure 2 As shown, the components primarily consist of a mounting plate 4 connected to the casing and a flattened fuel injection rod. The flattened rod has three slender, independent oil passages: first oil passage 1, second oil passage 2, and third oil passage 3. Each passage is equipped with multiple fuel injection holes. Fuel is injected through the passages and through the injection holes into the combustion chamber, where it mixes with the gas and burns.

[0003] Since the fuel injection rod has three deep-hole flow channels, it is difficult to process using traditional machining methods and has a high scrap rate. Due to the particularity of its deep-hole structure with a large aspect ratio, the part is prone to deformation during molding. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for manufacturing a fuel injection rod with a large long diameter deep hole, which solves the problems of high processing difficulty, high scrap rate and easy deformation of parts in traditional mechanical processing methods.

[0005] The present invention is achieved through the following technical solutions:

[0006] A method for manufacturing a fuel injection rod having a long diameter deep hole comprises the following steps:

[0007] S1. Build a three-dimensional model of the spray rod, a support model, and a powder discharge mechanism model to form a printing model;

[0008] The structure and pore size of each deposition layer of the three-dimensional model of the fuel injection rod are determined according to the shape and pore diameter characteristics and size of the fuel injection rod;

[0009] The support model includes an oblique support model and an interface support model, and the interface support model includes a first interface support model and a second interface support model;

[0010] The first interface support model is placed between the oblique support and the three-dimensional model of the spray rod, and the second interface support model is placed between the three-dimensional model of the spray rod and the powder discharge mechanism model;

[0011] The inclined surface of the oblique support model is at an inclined angle to the base plate;

[0012] S2, depositing the printed model layer by layer on the substrate;

[0013] S3. Vacuum stress relief on parts with substrates;

[0014] S4, performing post-processing to obtain a formed spray rod.

[0015] Furthermore, in S1 , the inclined surface of the oblique support model is inclined at an angle of 50° to 70° with the substrate.

[0016] Furthermore, in S1, the oblique support model is a hollow solid support, including a shell, and the interior of the shell is a hollow structure;

[0017] The outer periphery of the shell is surrounded by a first inclined plane, a first vertical plane, a horizontal plane, a second inclined plane, and a third inclined plane connected in sequence;

[0018] The horizontal plane is in parallel contact with the substrate, the third inclined plane is parallel to the spray rod profile, and the third inclined plane is at an inclined angle to the horizontal plane;

[0019] The first vertical surface is perpendicularly connected to the horizontal surface.

[0020] Furthermore, a hole is opened at the lower end of the first vertical surface, and the hole is communicated with the inner cavity of the shell.

[0021] Furthermore, in S1, the powder discharge mechanism includes a base, a powder discharge channel is prefabricated at the bottom of the base, and a plurality of powder discharge holes are prefabricated inside the base, and the number of the powder discharge holes corresponds to the number of oil passage holes on the mounting plate;

[0022] One end of the powder outlet hole is connected to the powder outlet channel, and the other end is connected to the oil passage hole.

[0023] Furthermore, the upper plane of the base is formed by sequentially connecting the first horizontal plane, the inclined plane and the second horizontal plane;

[0024] The inclined surface is parallel to the mounting plate surface of the fuel injection rod model.

[0025] Furthermore, the cross section of the powder outlet channel is triangular.

[0026] Furthermore, in S1, the interface support model is a support structure that combines grid support and rod support.

[0027] Furthermore, S3 specifically includes: performing vacuum stress relief on the part with the substrate at 960±10°C.

[0028] Furthermore, the post-processing in S4 specifically includes the following steps:

[0029] 4.1. Separate the substrate, separate the spray rod and the inclined support, and separate the spray rod and the powder discharge mechanism;

[0030] 4.2. Remove the remaining support and clamp the surface of the part.

[0031] Compared with the prior art, the present invention has the following beneficial technical effects:

[0032] The present invention discloses a method for manufacturing a fuel injection rod with a large long diameter and deep hole. The fuel injection rod is integrally formed using laser selective melting technology, and a new support structure is designed to assist part growth. The designed hollow solid structure not only ensures part formation, but also saves powder raw materials and facilitates powder removal. The designed powder discharge mechanism ensures easy powder removal and makes the support easy to remove.

[0033] Interface support is designed because it is a relatively weak support. If a solid support is used to connect the part, it is equivalent to the support and the part being integrated into one, and they cannot be separated at that time. Therefore, interface support is needed to connect the solid support to the part. After the part is formed, the interface support can be separated from the part entity using tools later.

[0034] Furthermore, the oblique support model is a hollow solid support, which saves materials. At the same time, a hole is opened at the lower end of the first vertical surface, and the hole is connected with the inner cavity of the shell to facilitate powder removal.

[0035] Furthermore, the present invention creatively designs a powder discharge mechanism with prefabricated powder discharge channels and holes. The number of holes corresponds to the number of oil passage holes on the mounting plate. One end of the hole is connected to the powder discharge channel, while the other end is connected to the oil passage hole. This design allows powder inside the part to flow smoothly out along the holes and channels during powder removal, improving powder removal efficiency. Furthermore, the powder removal mechanism is a physical feature, with the same printing parameters as the part, and possesses high strength. Furthermore, the interface supports connecting the part effectively prevent part deformation.

[0036] Furthermore, the cross section of the powder outlet channel is designed to be triangular, which can improve the top forming quality of the powder outlet channel. The triangular structure can be formed by its own structure without the need for design support and form self-support. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a three-dimensional model diagram of the fuel injection rod;

[0038] Figure 2 is an internal cross-sectional view of the fuel injection rod;

[0039] Figure 3 A 3D simulation diagram of the printed model created using 3D software;

[0040] Figure 4 A three-dimensional simulation diagram of the connection between the powder discharge mechanism model and the installation plate of the injection rod model;

[0041] Figure 5 It is a structural diagram of the oblique support model;

[0042] Figure 6 This is a schematic diagram of the modeling of the powder discharge mechanism;

[0043] Figure 7 It is a structural diagram of the powder discharging mechanism;

[0044] Figure 8 Schematic diagram of the structure of the interface support model.

[0045] Among them, 1. First oil channel; 2. Second oil channel; 3. Third oil channel; 4. Mounting plate;

[0046] 10. 3D model of the spray rod; 11. Oblique support model; 12. First interface support model; 13. Second interface support model; 14. Powder discharge mechanism model; 15. Base plate;

[0047] 111, first inclined surface; 112, first vertical surface; 113, hole; 114, horizontal surface; 115, second inclined surface; 116, third inclined surface;

[0048] 121. Grid support; 122. Rod support;

[0049] 141. Powder outlet channel; 142. Powder outlet hole; 143. First horizontal plane; 144. Inclined plane; 145. Second horizontal plane. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following is a further detailed description with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. That is, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0051] The components described and illustrated in the drawings and embodiments of the present invention may be arranged and designed in a variety of different configurations. Therefore, the detailed description of the embodiments of the present invention provided in the following drawings is not intended to limit the scope of the claimed invention, but merely represents a selected embodiment of the present invention. All other embodiments derived by those skilled in the art based on the drawings and embodiments of the present invention without inventive effort shall fall within the scope of protection of the present invention.

[0052] It should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, element, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to the process, element, method, article or device. In addition, the terms "horizontal" and "vertical" are based on the orientation and positional relationship of the devices or components shown in the drawings, and are only for the purpose of better describing the present invention, rather than requiring the devices, components or devices shown to have such a specific orientation, and therefore should not be understood as limiting the present invention.

[0053] The present invention discloses a method for manufacturing a fuel injection rod with a large long diameter deep hole, comprising the following steps:

[0054] S1, establishing a three-dimensional model of the spray rod 10, a support model and a powder discharge mechanism model 14 to form a printing model;

[0055] The structure and pore size of each deposition layer of the three-dimensional model 10 of the fuel injection rod are determined according to the shape and pore size characteristics and size of the fuel injection rod;

[0056] The support model includes an oblique support model 11 and an interface support model, and the interface support model includes a first interface support model 12 and a second interface support model 13;

[0057] The first interface support model 12 is placed between the oblique support and the spray rod three-dimensional model 10, and the second interface support model 13 is placed between the spray rod three-dimensional model 10 and the powder discharge mechanism model 14;

[0058] The inclined surface of the oblique support model 11 is at an inclined angle to the base plate 15;

[0059] S2, depositing the printed model layer by layer on the substrate 15;

[0060] S3. Perform vacuum stress relief on the part with substrate 15 at 960±10°C;

[0061] S4, performing post-processing to obtain a formed spray rod.

[0062] like Figure 5 As shown, the inclined support model 11 is a hollow solid support, including a shell with a hollow interior. The shell's periphery is formed by a first inclined surface 111, a first vertical surface 112, a horizontal surface 114, a second inclined surface 115, and a third inclined surface 116, which are connected in sequence. The horizontal surface 114 is parallel to the base plate 15, and the third inclined surface 116 is parallel to the spray rod profile and inclined at an angle to the horizontal surface 114. The first vertical surface 112 is perpendicular to the horizontal surface 114.

[0063] like Figure 6 As shown, a hole 113 is formed at the lower end of the first vertical surface 112, and the hole 113 is connected to the inner cavity of the shell. The hole 113 is a rectangular outlet to facilitate powder removal.

[0064] The second inclined surface 115 is designed to allow the oblique support model 11 to avoid the mounting plate 4 at the bottom of the component, thereby creating a gap between the component and the oblique support model 11 .

[0065] like Figure 7As shown, the powder discharge mechanism includes a base, a powder discharge channel 141 is prefabricated at the bottom of the base, and a plurality of powder discharge holes 142 are prefabricated inside the base, and the number of the powder discharge holes 142 corresponds to the number of the oil passage holes on the spray rod; one end of the powder discharge hole 142 is connected to the powder discharge channel 141, and the other end is connected to the oil passage hole on the spray rod.

[0066] The upper plane of the base is formed by sequentially connecting a first horizontal plane 143, an inclined plane 144 and a second horizontal plane 145; the inclined plane 144 is parallel to the surface of the mounting plate 4 of the spray rod model.

[0067] The features and performance of the present invention are further described in detail below with reference to the embodiments.

[0068] The present invention discloses a method for manufacturing a fuel injection rod with a large long diameter deep hole, and the specific implementation steps are as follows:

[0069] Step 1: Use 3D model design software to build a 3D solid model of the spray rod suitable for laser selective melting. The 3D model of the spray rod is as follows: Figure 1 As shown, the schematic diagram of the deep hole structure with large aspect ratio is as follows Figure 2 shown.

[0070] Step 2: Use support design software to design a support model based on the part's structural characteristics to assist in part molding. Due to the unique structure of the deep-hole flow channel with a large aspect ratio, the closer the flow channel is to the plane of the base plate 15, the better the part's self-support and surface roughness. To ensure self-support while also taking into account part deformation and ensuring a smooth flow channel surface, the spray rod component is positioned at a 50° to 70° angle to the plane of the base plate 15.

[0071] When the parts are placed at 60 degrees, the distance between the spray rod head and the base plate 15 is too large, so a diagonal support model 11 is designed. The diagonal support model 11 is a hollow solid support structure to save materials. Figure 5 As shown, the wall thickness is 1.5mm, and the overall shape is triangular. The hypotenuse of the inclined support is parallel to the injection rod surface, with a spacing of 2mm. The inclined support and the injection rod are separated by a first interface support model 12, which uses a traditional combined support connection.

[0072] The diameter of the cylindrical boss on the spray rod is Φ8mm. Since it protrudes 4mm from the spray rod, when designing the support, the following should be selected: Figure 8 The traditional combined support shown is a 0.5×0.5mm grid support 121 and a Φ0.4mm rod support 122. The combined support is 6mm long and 3.8mm wide, connected to a cylindrical boss on the top and a hollow solid support on the bottom.

[0073] Since the mounting plate 4 is thin, it is easy to deform during the forming process. Therefore, when designing the support, its support structure must be reinforced. Therefore, a second interface support model 13 is designed between the spray rod three-dimensional model 10 and the powder discharge mechanism model 14. The second interface support model 13 also adopts the following method: Figure 8 The support structure shown is a combination of a traditional grid support 121 and a rod support 122. Figure 8 As shown, the grid support 121 here adopts the parameters of 0.5×0.5 mm, and the rod support 122 adopts a Φ0.4 mm cylinder.

[0074] At the same time, considering that there is an oil passage hole under the mounting plate 4, a powder outlet mechanism is designed. The powder outlet mechanism has a dense structure, with a 4mm wide regular triangle powder outlet channel 141 at the bottom, and 3 powder outlet holes 142 at the top of the channel connected to the oil passage hole. Figure 7 shown.

[0075] Step 3: Use laser rapid prototyping equipment to form parts on the substrate 15. Three parts can be printed on each plate. The parts are arranged parallel to each other with a spacing of 20 mm.

[0076] Step 4: Use a vacuum heat treatment furnace to perform vacuum stress relief on the parts with the substrate 15.

[0077] Step 5: Use wire cutting equipment to separate the substrate 15 from the parts, separate the spray rod from the hollow solid support, and separate the surface between the spray rod and the powder discharge mechanism;

[0078] Step 6. Use a hammer and chisel to remove the remaining supports on the spray rod; for the remaining high points of the supports on the rod, use an air gun and a rotary file to plier and remove them.

[0079] The spray rod produced using the manufacturing method of the present invention has a 100% pass rate, and its mechanical properties meet design requirements. Powder and supports are also easily removed, with simple tools allowing for support removal. Compared to using only interface supports and rod-shaped supports 122 to assist in part formation, this method reduces powder consumption and improves support removal efficiency by 30%.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for manufacturing a fuel injection rod with a large long diameter deep hole, characterized in that: The following steps are involved: S1, establishing a three-dimensional model of the spray rod (10), a support model and a powder discharge mechanism model (14) to form a printing model; The structure and pore size of each deposition layer of the three-dimensional model (10) of the fuel injection rod are determined according to the shape and pore size characteristics and size of the fuel injection rod; The support model includes an oblique support model (11) and an interface support model, and the interface support model includes a first interface support model (12) and a second interface support model (13); The first interface support model (12) is placed between the oblique support model (11) and the three-dimensional model of the spray rod (10), and the second interface support model (13) is placed between the three-dimensional model of the spray rod (10) and the powder discharge mechanism model (14); The inclined surface of the oblique support model (11) is at an inclined angle to the base plate (15); S2, depositing the printed model layer by layer on the substrate (15); S3, vacuum stress relief is performed on the part with the substrate (15); S4, performing post-processing to obtain a formed spray rod; In S1, the oblique support model (11) is a hollow solid support, including a shell, and the interior of the shell is a hollow structure; The outer periphery of the shell is surrounded by a first inclined surface (111), a first vertical surface (112), a horizontal surface (114), a second inclined surface (115), and a third inclined surface (116) connected in sequence; The horizontal plane (114) is in parallel contact with the base plate (15), the third inclined plane (116) is parallel to the spray rod profile, and the third inclined plane (116) is at an inclined angle to the horizontal plane (114); The first vertical surface (112) is vertically connected to the horizontal surface (114); A hole (113) is formed at the lower end of the first vertical surface (112), and the hole (113) is connected to the inner cavity of the shell; In S1, the powder discharge mechanism includes a base, a powder discharge channel (141) is prefabricated at the bottom of the base, and a plurality of powder discharge holes (142) are prefabricated inside the base, and the number of the powder discharge holes (142) corresponds to the number of oil passage holes on the mounting plate (4); One end of the powder outlet hole (142) is connected to the powder outlet channel (141), and the other end is connected to the oil passage hole.

2. The method for manufacturing a fuel spray rod with a large long diameter deep hole according to claim 1, characterized in that: In S1, the inclined surface of the inclined support model (11) is inclined at an angle of 50°-70° with the base plate (15).

3. The method for manufacturing a fuel spray rod with a large long diameter deep hole according to claim 1, characterized in that: The upper plane of the base is formed by sequentially connecting a first horizontal plane (143), an inclined plane (144) and a second horizontal plane (145); The inclined surface (144) is parallel to the profile of the mounting plate (4) of the three-dimensional model (10) of the fuel injection rod.

4. The method for manufacturing a fuel spray rod with a long diameter deep hole according to claim 1, characterized in that: The cross section of the powder outlet channel (141) is triangular.

5. The method for manufacturing a fuel spray rod with a large long diameter deep hole according to claim 1, characterized in that: In S1, the interface support model is a support structure that combines grid support (121) and rod support (122).

6. The method for manufacturing a fuel spray rod with a long diameter deep hole according to claim 1, characterized in that: S3 specifically comprises: performing vacuum stress relief on the part with the substrate (15) at 960±10°C.

7. The method for manufacturing a fuel spray rod with a long diameter deep hole according to claim 1, characterized in that: S4 post-processing details The following steps are involved: 4.

1. Separate the base plate (15), separate the spray rod and the oblique support, and separate the spray rod and the powder discharge mechanism; 4.

2. Remove the remaining support and clamp the surface of the part.

Images