Machining method for thin-wall diffuser of supercharger

Abstract

The invention discloses a machining method for a thin-wall diffuser of a supercharger. The manufacturing quality is stable and reliable. Comprising 10 procedures: heat treatment; 20, roughly turning a large end; 30, roughly turning a small end; 40, semi-finish turning is conducted on the outer circle, the inner hole and the end face of the large end; 50, semi-finish turning is conducted on the outer circle, the inner hole and the end face of the small-end step; 60, scribing, namely scribing a vertical center line on the small end face and leading the vertical center line to the outer circle of the large end; 70, drilling and milling each hole, and reserving allowance; 80, the large end face is subjected to semi-finish turning, and the flatness is guaranteed to be 0.05; 90, roughly milling the blade and the runner; 100 working procedure: heat treatment for destressing; 110, the large end face is subjected to finish turning; 120, the small end face is subjected to finish turning; 130, the large end face is subjected to finish turning, and the flatness is guaranteed to be 0.03; 140, drilling and milling each hole in place after aligning and scribing; 150, finish milling of the blade and the flow channel; 160, a large outer circle is subjected to finish turning.

Description

Technical Field

[0001] The present invention relates to the technical field of ship and warship engine manufacturing, and in particular to a method for processing a supercharger thin-wall diffuser (LD7). Background Art

[0002] The supercharger is an important core model, and it plays an indescribable important role in the domestic and international shipbuilding markets. The technical level of the supercharger directly affects the working capacity of ships and ship diesel engines. In order to improve the quality of the parts of this model and our company's manufacturing and processing capabilities, it is necessary to further innovate and improve the processing methods of the parts of this model. This patent will explain the innovative improvements to the diffuser.

[0003] The diffuser is the core part of the turbocharger. Its main function is to effectively convert the airflow with large kinetic energy coming out of the impeller into pressure energy. The quality of the diffuser directly affects the level of the converted pressure energy. Since the material of the diffuser is LD7, the rigidity during the processing is poor, and the thickness of the large end is thin and the blade processing allowance is large, which makes the overall part easy to deform after processing. During the current processing in the factory, once serious processing deformation occurs, it is often necessary to borrow the allowance from the other end, which makes the subsequent processing complicated and prone to quality problems. Therefore, these high-requirement dimensions must be taken into account during the processing, and the deformation of each process must be controlled to ensure the stable and reliable manufacturing quality of the part.

[0004] The supercharger is composed of diffuser, compressor impeller, casing, volute and other components. The diffuser to be introduced in this patent is the core component of the supercharger and one of the key parts. The traditional processing route of the diffuser is as follows:

[0005] 10th process: heat treatment, ensuring hardness 120HB;

[0006] →20th process: rough turning of the big end;

[0007] →30 process: rough turning of small end;

[0008] →40 process: fine turning of large outer circle, semi-fine turning of positioning end face and positioning hole for tooling;

[0009] →50 process: semi-finishing turning of blade end;

[0010] →60 process: drilling and milling of holes;

[0011] →70 process: rough milling of blades and flow channels;

[0012] →80 process: finishing the large end face;

[0013] →90 process: fine turning of small end face;

[0014] →100 process: fine milling of blades and flow channels;

[0015] →110 processes: nipper, deburring and engraving;

[0016] There are 11 processes in total.

[0017] Through on-site follow-up investigation, it is found that the processing difficulties of the diffuser are mainly in the following aspects:

[0018] (1) The large outer circle of step 40 has been processed to the drawing size φ544, but if the deformation of the blade during subsequent milling and finishing is large, the size may be out of tolerance.

[0019] (2) The hole and depth of φ20 in process 60 have been processed to the requirements of the drawing. When the depth is in place, it will lead to large deformation in the subsequent process. When the end face allowance is needed, the depth dimension will be out of tolerance.

[0020] (3) After the semi-finishing turning of the blade end in process 50, the positioning end face that had been processed in process 40 was deformed due to stress concentration. The flatness of the end face was out of tolerance by 0.05. The deformation of the positioning end would affect the positioning of the subsequent tooling and the accumulation of deformation.

[0021] (4) After rough milling of the blades and flow channels in process 70, the overall deformation was large. A heat treatment stress relief test was done before rough milling, but the improvement effect was not obvious. Heat treatment stress relief after rough milling would cause large overall deformation, and the subsequent margin would be insufficient.

[0022] (5) After the blade end is fine-turned in step 90, the positioning end face that has been processed in step 80 is deformed due to stress concentration. The flatness of the end face exceeds the tolerance of 0.03, which will affect the positioning of the subsequent tooling and the accumulation of deformation.

[0023] According to the processing route and on-site tracking results, it can be found that the processing difficulties of the diffuser are all related to stress deformation, and the processing quality cannot be effectively controlled, thus affecting the subsequent processing quality. Summary of the invention

[0024] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for processing a thin-walled diffuser (LD7) of a supercharger, which has stable and reliable manufacturing quality.

[0025] The object of the present invention is achieved in that:

[0026] A method for processing a supercharger thin-wall diffuser (LD7), comprising the following steps:

[0027] 10. Process: heat treatment;

[0028] 20th process: rough turning of the big end;

[0029] 30 process: rough turning of small end;

[0030] Process 40: Semi-finishing turning of the outer circle, inner hole and end face of the large end. The outer circle and end face of the large end are used for semi-finishing turning positioning in the next process;

[0031] 50th process: semi-finishing turning of the outer circle, inner hole and end face of the small end step;

[0032] 60 Steps: Marking: Mark a vertical center line on the small end surface and lead it to the outer circle of the large end;

[0033] 70 steps: drilling and milling each hole, and leaving allowance;

[0034] Process 80: semi-finishing turning of the large end surface to ensure a flatness of 0.05 for rough milling positioning in the next process;

[0035] 90 process: rough milling of blades and flow channels;

[0036] 100 process: heat treatment to relieve stress and reduce subsequent processing deformation;

[0037] Process 110: Semi-finish turning of the large end face to eliminate the deformation of the large end face caused by process 90 (can eliminate most of it, but not completely).

[0038] 120 process: fine turning of small end face;

[0039] Process 130: Fine turning of the large end surface to ensure a flatness of 0.03 for fine milling positioning in the next process;

[0040] 140 process: after aligning and marking, drill and mill each hole into place;

[0041] 150 process: fine milling of blades and flow channels;

[0042] 160 process: fine turning of large outer circle.

[0043] Preferably, in step 10, the heat treatment ensures that the hardness is above 120 HB.

[0044] Preferably, the method further includes step 170: clamping and deburring.

[0045] Preferably, in the 90 steps, the machining allowance for rough milling of the blade is 1.5 mm.

[0046] Preferably, in the 110 process, a small amount of margin is left on the large end surface, and the three jaws are loosened and lightly clamped before turning to size.

[0047] Due to the adoption of the above technical solution and the verification of the new processing route, a reliable and stable manufacturing method has been found for the supercharger diffuser, successfully solving the above problems. The beneficial effects of the present invention are as follows (the following serial numbers correspond to the processing difficulties):

[0048] (1) In order to ensure that the processing deformation does not affect the size of the large outer circle, the 40-step fine turning of the large outer circle is adjusted to the 160-step process. At the same time, since the small end blade has been processed in place before the 160-step process, the large outer circle cannot be processed by three-jaw clamping. Therefore, the 340X-18 milling tool is used.

[0049] (2) The φ20 hole in the original process 60 is no longer processed to the required depth. The φ20 hole is processed as φ18 with a 1.5 depth margin. At the same time, in order to ensure the positional relationship of the holes processed twice, a marking process is added to facilitate alignment.

[0050] (3) The new process re-polishes the large-end positioning end face before rough milling in the 90-step process to ensure a flatness of 0.05, which is used for positioning the rough milling tooling and avoids the accumulation of deformation.

[0051] (4) The new process adds heat treatment to relieve stress after the rough milling process of step 90. The rough milling allowance of the blade is large, and the overall stress can be better released after heat treatment, making subsequent processing more stable. At the same time, the machining allowance before rough milling of the blade is adjusted from 0.8mm to 1.5mm to ensure that there is enough allowance to remove the deformation caused by heat treatment.

[0052] (5) The new process re-polishes the large-end positioning end face before the 130 step fine milling to ensure a flatness of 0.03, which is used for positioning the fine milling tooling and avoids the accumulation of deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1-Figure 11 Schematic diagram of the processing process;

[0054] Fig.12 This is a schematic diagram of clamping positioning symbols. DETAILED DESCRIPTION

[0055] A processing method for a supercharger thin-wall diffuser (LD7), wherein the processing route is: 10 heat treatment → 20 rough turning → 30 rough turning → 40 semi-finishing turning → 50 semi-finishing turning → 60 clamping (marking) → 70 rough milling (each hole) → 80 semi-finishing turning → 90 rough milling (blade) → 100 heat treatment (stress relief) → 110 fine turning → 120 fine turning → 130 fine turning → 140 fine milling (each hole) → 150 fine milling (blade) → 160 fine turning → 170 clamping.

[0056] The final processing route is as follows:

[0057] 10th process: heat treatment, ensuring hardness 120HB;

[0058] →20 process: rough turning of big end and inner hole; (see Figure 1 )

[0059] →30 process: Rough turning of small end and stepped inner hole (see Figure 2 );

[0060] →40 process: semi-finishing turning of large outer circle, semi-finishing turning of positioning end face and positioning hole for tooling; (see Figure 3 )

[0061] →50 process: semi-finishing turning of blade end (see Figure 4 );

[0062] →60 process: marking;

[0063] →70 process: drilling and milling each hole, leaving allowance (see Figure 5 ), drill according to the process drawing Through hole, drill Flat bottom hole, depth to top surface dimension;

[0064] →80 process: precision turning of the large end surface to ensure a flatness of 0.05, for rough milling positioning in the next process; (see Figure 6 )

[0065] →90 process: rough milling blades and flow channels (see Figure 7 );

[0066] →100 process: heat treatment to relieve stress and reduce subsequent processing deformation;

[0067] →110 process: semi-finishing turning of large end face; (see Figure 8 ) The milling amount of the blades and flow channels in the rough milling process of 90 is large, resulting in large deformation of the large end surface, which is not conducive to the processing of the 120 process and subsequent processes. Therefore, the processing of the large end surface in the 110 process can eliminate some of the deformation caused by the 90 process (it can eliminate most of the deformation, but not completely eliminate it), which is conducive to ensuring the size A±0.1 and At the same time, the accumulation of deformation is avoided.

[0068] →120 process: fine turning of small end face; (see Fig. 9 )

[0069] →130 process: fine turning of the large end surface to ensure a flatness of 0.03 for fine milling positioning in the next process; (see Fig.10 )

[0070] →140 process: drill and mill all holes in place, find the alignment and mark them, then expand and mill according to the drawing Flat bottom hole, depth 10;

[0071] →150 process: fine milling of blades and flow channels (see Fig.11 );

[0072] →160 process: finishing the large outer circle to size And external chamfer;

[0073] →170 processes: nipper, deburring and engraving;

[0074] There are 17 processes in total.

[0075] Finally, it should be noted that the above preferred 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 through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A method for processing a thin-walled diffuser of a supercharger, characterized in that: Including the following processes:

10. Process: heat treatment; 20th process: rough turning of the big end; 30 process: rough turning of small end; Process 40: Semi-finishing turning of the outer circle, inner hole and end face of the large end. The outer circle and end face of the large end are used for semi-finishing turning positioning in the next process; 50th process: semi-finishing turning of the outer circle, inner hole and end face of the small end step; 60 Steps: Marking: Mark a vertical center line on the small end surface and lead it to the outer circle of the large end; 70 steps: drilling and milling each hole, and leaving allowance; Process 80: semi-finishing turning of the large end surface to ensure a flatness of 0.05 for rough milling positioning in the next process; 90 process: rough milling of blades and flow channels; 100 process: heat treatment to relieve stress and reduce subsequent processing deformation; 110 process: semi-finishing turning of large end face; 120 process: fine turning of small end face; Process 130: Fine turning of the large end face further eliminates the deformation of the large end face and ensures a flatness of 0.03, which is used for fine milling positioning in the next process; 140 process: after aligning and marking, drill and mill each hole into place; 150 process: fine milling of blades and flow channels; Process 160: Finish turning of large outer circle. Used the 340X-18 milling tool.

2. The method for processing a supercharger thin-wall diffuser according to claim 1, characterized in that: In the 10th process, the heat treatment ensures that the hardness is above 120HB.

3. The method for processing a supercharger thin-wall diffuser according to claim 1, characterized in that: Also includes 170 operations: nippers, deburring.

4. The method for processing a supercharger thin-wall diffuser according to claim 1, characterized in that: In process 90, the machining allowance for rough milling of the blade is 1.5mm.

5. The method for processing a supercharger thin-wall diffuser according to claim 1, characterized in that: In the 110 process, a small amount of margin is left on the large end face, and the three jaws are loosened and lightly clamped before turning to size.

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