Method for precisely machining porous parts in chemical milling area

Abstract

The invention provides a method for precisely machining a porous part in a chemical milling area. The method comprises the steps that a part sample plate of the porous flat plate part and a chemical milling sample plate are prepared; the surface of the blank is coated with chemical milling protection glue, the part sample plate is placed in the center of the blank, and a hole is drilled in the blank to serve as a chemical milling positioning hole; taking down the part sample plate on the blank, placing the chemical milling sample plate on the blank, and performing chemical milling on the blank by means of the chemical milling sample plate to obtain a semi-finished part; determining a milling area on the semi-finished product part; a positioning hole and the outer contour of the part are machined in a machine tool base plate, and then the semi-finished part is placed on the machine tool base plate and positioned; and performing numerical control milling forming on the milling area on the semi-finished product part, and obtaining a finished product part after machining is completed. The method is easy to operate, needs less human resources, and can be popularized to production and machining of flat plate parts with regular or irregular shapes in a chemical milling area.

Description

Technical Field

[0001] The invention relates to the field of parts processing, and in particular to a method for precise processing of porous parts in a milling area. Background Art

[0002] In aircraft production, aluminum alloy flat plate parts account for a relatively large proportion, and flat plate parts with through holes in the milling area are generally used in seats and are an important component of the aircraft.

[0003] For such parts, the reason why the domestic molding method of drilling first and then milling the hole area is not adopted is that milling will cause erosion, affecting the accuracy of the hole position and hole diameter. The calculation of the erosion area is complicated and has too many influencing factors, which is not conducive to the actual production and processing of parts.

[0004] Therefore, the traditional stamping method is used in the processing of such aircraft aluminum alloy sheet metal parts. The shortcomings of this method are that it relies too much on manually finding the center position of the through hole for positioning, that it depends to a large extent on the quality and life of the punching die, and that there is a large stamping deformation for porous parts. This method will cause the size and position of the punched through hole to deviate greatly from the original state, and the production cycle is long and the process form is relatively backward.

[0005] For hole making, accurate digital model and CNC milling can achieve the purpose of precise processing. However, the most critical problem of this method is how to effectively locate. Therefore, in order to solve such problems, it is necessary to study a precise processing method that can avoid more manual operations and efficiently and accurately form through holes in the milling area of ​​flat parts. Summary of the invention

[0006] In order to solve the problem of precise processing of porous aircraft aluminum alloy sheet metal parts in the milling area, the present invention overcomes the shortcomings of the prior art and provides a method for precise processing of porous parts in the milling area, using precise digital models, precise positioning, and then CNC milling to form the parts.

[0007] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0008] A method for precision machining of porous parts in a milling area, comprising:

[0009] Step 1: First, according to the drawing of the porous flat plate part to be prepared, a part sample and a milling sample of the porous flat plate part are prepared;

[0010] Step 2: Apply chemical milling protective glue on the surface of the rough material, place the part sample at the center of the rough material, and leave enough chemical milling margin around it; drill holes on the rough material through the positioning holes on the part sample as chemical milling positioning holes;

[0011] Step three, remove the part template on the rough material, place the chemical milling template on the rough material, so that the positioning hole on the chemical milling template overlaps with the chemical milling positioning hole processed on the rough material; first insert the positioning pin into the positioning hole to fix the position of the chemical milling template, use the tool to mark the edge of the chemical milling area of ​​the chemical milling template to form a chemical milling surface on the rough material, and carve the outline of the chemical milling area on the rough material, then tear off the chemical milling protective glue on the chemical milling surface, pull out the positioning pin, remove the chemical milling template, and then immerse the rough material in the chemical milling groove for chemical milling to obtain a semi-finished part after chemical milling;

[0012] Step 4, determining the milling area on the semi-finished part based on the part template;

[0013] Step 5, the first CNC milling process: CNC milling the positioning holes corresponding to the positioning holes on the part template and the outline of the part template on the machine bedplate; then place the semi-finished part on the machine bedplate so that the positioning holes on the semi-finished part and the positioning holes milled on the machine bedplate correspond to each other up and down, insert the positioning pins, fix the semi-finished part to the machine bedplate with a clamp, and then pull out the positioning pins;

[0014] Step six, perform a second CNC milling process: the milling area on the semi-finished part is CNC milled and formed, and the finished part is obtained after the processing is completed.

[0015] Furthermore, the appearance, structure and size of the part template are basically the same as those of the porous flat plate-type parts, and the only difference is that at least two positioning ears are provided on the side of the part template, and positioning holes are processed on the ears.

[0016] Furthermore, the shape and size of the chemical milling template are basically the same as those of the part template, and the only difference is that there are no other features on the surface of the chemical milling template except the chemical milling area, ears and positioning holes.

[0017] Furthermore, the chemical milling allowance is at least 50 mm, and the CNC milling allowance is at least 40 mm.

[0018] Furthermore, the area where all features of the corresponding part template are located on the semi-finished part is determined as the milling processing area.

[0019] Furthermore, the milling area includes the milling surface on the part and the area where all features are located.

[0020] Furthermore, the features include through holes and windows inside the part template and the outer contour of the part template.

[0021] Furthermore, the method also includes: inspecting the finished parts according to the part template to check whether the through holes, windows, etc. milled on the part template are consistent with the part template.

[0022] The present invention provides a method for the precise processing and forming of porous aircraft aluminum alloy sheet metal parts in the milling area. Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. Basically realize the whole process of mechanical automation and precise processing and manufacturing, which greatly avoids the influence of human factors on the through holes in the milling area.

[0024] 2. The method for precise positioning of parts after chemical milling is simple, effective and accurate. The parts formed by CNC milling have improved the accuracy of through-hole position and aperture, ensuring product quality.

[0025] 3. Greatly shortened the production cycle and improved work efficiency.

[0026] 4. The method described in the present invention has a wide range of applications and low operational difficulty, and can solve the problem of secondary precision processing and forming of most aircraft aluminum alloy flat plate parts in the milling area after chemical milling. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram showing the part sample being placed in the center of the rough material;

[0028] Figure 2 This is a schematic diagram of a semi-finished part with positioning holes and after milling;

[0029] Figure 3 This is a schematic diagram after running the first CNC milling process;

[0030] Figure 4 This is a schematic diagram after the second CNC milling process;

[0031] Figure 5 It is the final flat part product.

[0032] In the figure: 1-raw material, 2-part sample, 3-positioning hole, 4-milling surface, 5-milling area, 6-machine bed plate, 7-part after the second CNC milling, 8-through hole. DETAILED DESCRIPTION

[0033] like Figure 1-5 As shown, the present invention provides a method for precision machining of porous parts in a milling area, comprising:

[0034] Step 1: First, according to the drawing of the porous flat plate part to be prepared, prepare a part template and a milling template of the porous flat plate part, wherein the shape, structure and size of the part template are basically the same as those of the porous flat plate part, and the only difference is that at least two positioning ears are set on the side of the part template 2, and the positioning holes 3 are processed on the ears; Figure 1As shown, the sample part 2 is a template made according to the porous flat plate-like parts to be prepared. In this embodiment, the lower part of the sample part 2 is the through hole 8 area, and the upper part has two viewing windows; different from the parts, positioning ears and positioning holes are made at the upper end of the sample part.

[0035] The shape and size of the chemical milling template are basically the same as those of the part template. The only difference is that, except for the chemical milling area, ears and positioning holes, there are no other features on the surface of the chemical milling template, such as holes, grooves or other structural features; wherein, the chemical milling area completely covers the area of ​​through holes that require CNC machining of porous parts; the chemical milling area is a through cavity, that is, the chemical milling template is a template with the same shape as the part, with only the chemical milling area on its surface, and ears and positioning holes arranged above it, without other structural features.

[0036] Step 2: Apply chemical milling protective glue on the surface of the rough material 1, place the part sample 2 at the center of the rough material 1, and leave enough chemical milling allowance (at least 50mm) around it. The chemical milling allowance should be larger than the CNC milling allowance (at least 40mm);

[0037] Through the positioning hole 3 on the part template 2, a hole is drilled on the rough material 1 as a chemical milling positioning hole;

[0038] Step three, remove the part template 2 on the rough material 1, and place the chemical milling template on the rough material 1, so that the positioning holes on the chemical milling template overlap with the chemical milling positioning holes processed on the rough material 1; first insert the positioning pin into the positioning hole to fix the position of the chemical milling template, and use the tool to mark the edge of the chemical milling area of ​​the chemical milling template to form a chemical milling surface 4 on the rough material 1, and carve the outline of the chemical milling area on the rough material 1, and then tear off the chemical milling protective glue on the chemical milling surface 4, pull out the positioning pin, remove the chemical milling template, and then immerse the rough material 1 in the chemical milling groove for chemical milling treatment to obtain a semi-finished part after chemical milling; Figure 2 As shown, the oblique line area is the milling surface 4; this semi-finished part only includes the milling positioning hole and the milling surface 4;

[0039] Step 4, determining the milling area 5 on the semi-finished part based on the part template 2; wherein the area on the semi-finished part corresponding to all the features of the part template 2 is determined as the milling area 5, and the milling area 5 should be a continuous area, including the milling surface 4 on the part and the area where all the features are located; wherein the features include the through holes and windows inside the part template 2 and the outer contour of the part template 2;

[0040] Step 5, first CNC milling: CNC milling out positioning holes corresponding to the positioning holes on the part template 2 and the outer contour of the part template 2 on the machine bed plate 6; Figure 3 As shown;

[0041] Place the semi-finished parts on the machine bed plate 6 so that the positioning holes on the semi-finished parts overlap with the positioning holes milled on the machine bed plate 6, insert the positioning pins, fix the semi-finished parts on the machine bed plate 6 with a clamp, and then remove the positioning pins;

[0042] Step 6: Perform the second CNC milling process: perform CNC milling process on the milling area 5 of the semi-finished part to shape the through holes, windows and other features in the milling area 5. After the processing is completed, the finished part is obtained, such as Figure 5 As shown; inspect the finished parts according to the part template, and check whether the through holes, windows, etc. milled on the part template are consistent with the part template.

[0043] In summary, the present invention provides a method for the precise processing and forming of porous aircraft aluminum alloy sheet metal parts in the milling area. Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. Basically realize the whole process of mechanical automation and precise processing and manufacturing, which greatly avoids the influence of human factors on the through holes in the milling area.

[0045] 2. The method for precise positioning of parts after chemical milling is simple, effective and accurate. The parts formed by CNC milling have improved the accuracy of through-hole position and aperture, ensuring product quality.

[0046] 3. Greatly shortened the production cycle and improved work efficiency.

[0047] 4. The method described in the present invention has a wide range of applications and low operational difficulty, and can solve the problem of secondary precision processing and forming of most aircraft aluminum alloy flat plate parts in the milling area after chemical milling.

Claims

1. A method for precision machining of porous parts in a milling area, characterized in that: include: Step 1: First, according to the drawing of the porous flat plate part to be prepared, a part sample and a milling sample of the porous flat plate part are prepared; Step 2: Apply chemical milling protective glue on the surface of the rough material, place the part sample at the center of the rough material, and leave enough chemical milling margin around it; drill holes on the rough material through the positioning holes on the part sample as chemical milling positioning holes; Step three, remove the part template on the rough material, place the chemical milling template on the rough material, so that the positioning hole on the chemical milling template overlaps with the chemical milling positioning hole processed on the rough material; first insert the positioning pin into the positioning hole to fix the position of the chemical milling template, use the tool to mark the edge of the chemical milling area of ​​the chemical milling template to form a chemical milling surface on the rough material, and carve the outline of the chemical milling area on the rough material, then tear off the chemical milling protective glue on the chemical milling surface, pull out the positioning pin, remove the chemical milling template, and then immerse the rough material in the chemical milling groove for chemical milling to obtain a semi-finished part after chemical milling; Step 4, determining the milling area on the semi-finished part based on the part template; Step 5, the first CNC milling process: CNC milling the positioning holes corresponding to the positioning holes on the part template and the outline of the part template on the machine bedplate; then place the semi-finished part on the machine bedplate so that the positioning holes on the semi-finished part and the positioning holes milled on the machine bedplate correspond to each other up and down, insert the positioning pins, fix the semi-finished part to the machine bedplate with a clamp, and then pull out the positioning pins; Step six, perform a second CNC milling process: the milling area on the semi-finished part is CNC milled and formed, and the finished part is obtained after the processing is completed.

2. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The appearance, structure and size of the part template are basically the same as those of the porous flat plate parts, and the only difference is that at least two positioning ears are arranged on the side of the part template, and positioning holes are processed on the ears.

3. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The shape and size of the chemical milling template are basically the same as those of the part template. The only difference is that there are no other features on the surface of the chemical milling template except the chemical milling area, ears and positioning holes.

4. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The chemical milling allowance is at least 50 mm, and the CNC milling allowance is at least 40 mm.

5. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The area where all features of the corresponding part template are located on the semi-finished part is determined as the milling area.

6. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The milling area includes the milled surface on the part and the area where all features are located.

7. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The features include through holes and windows inside the part template and the outer contour of the part template.

8. The method for precise machining of porous parts in a milling area according to claim 1, characterized in that: The method further comprises: inspecting the finished parts according to the part template to check whether the through holes, windows, etc. milled on the part template are consistent with the part template.

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