Disc type piece narrow cavity linkage precision turning machining method

Abstract

The application discloses a precision machining method for disc-shaped parts with narrow cavities, which comprises the following steps: firstly, analyzing the process of the narrow cavity of the part, and measuring the size such as the opening and the depth; secondly, drawing a middle-difference model; thirdly, designing a tool structure according to the model, dividing the machining area, and determining the tool specification shape, for example, the area A is composed of a rectangle, and the tool 1 is used for machining; fourthly, programming and simulating the machining, and setting reasonable cutting parameters, wherein the tool is retracted and high-pressure cooling is performed every 1-2 layers of cutting to prevent chip extrusion and tool breakage; and finally, clamping the part, calling the program, and machining. The method overcomes the problems of chip extrusion and tool breakage in traditional machining, improves the machining precision and stability, has been successfully applied to the machining of a boltless connection baffle mounting groove of a powder alloy turbine disc, and has completed the delivery of multiple turbine discs, thereby creating remarkable economic benefits. The method is suitable for the machining of various disc-shaped parts with narrow groove structures, and has a wide application prospect in the manufacturing field of aero-engines.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aero-engine manufacturing technology, in particular to a precision machining method for narrow cavity linkage turning. BACKGROUND

[0002] In the field of aero-engine manufacturing, disc parts are key components of turbine rotor parts, and their performance and quality play a crucial role in the overall operation of the engine.

[0003] With the continuous development of aero-engine technology, the requirements for disc parts are becoming increasingly stringent. Such parts usually have the characteristic of high material hardness, which leads to significant work hardening phenomenon during machining. More complex is that their structure contains various narrow cavities, which poses a great challenge to machining.

[0004] Traditional numerical control lathes and tool structures have many limitations when machining such parts. Due to the special structure of narrow cavities, tool extrusion and tool breakage are likely to occur during machining. The extrusion phenomenon not only affects the surface quality of the machining, but also may cause tool damage and increase machining costs. The tool breakage problem may directly cause the tool to be scrapped, and at the same time cause damage to the parts, leading to part rejection due to excessive difference. In addition, narrow cavities are also prone to interference and collision problems, which further increases the risk of machining, making it difficult to ensure the machining precision of the parts and unable to meet the high precision and high quality requirements of aero-engine disc parts. SUMMARY

[0005] To solve the above problems, a precision machining method for narrow cavity linkage turning of disc parts is disclosed.

[0006] The specific technical solutions are as follows:

[0007] A precision machining method for narrow cavity linkage turning of disc parts, comprising the following steps:

[0008] Step 1: Process analysis of the narrow cavity of the part, measure the opening, depth, length, and size of the transition fillet of the cavity of the part;

[0009] Step 2: Draw the difference model of the narrow cavity of the part, and establish the difference model of the narrow cavity of the part;

[0010] Step 3: Tool structure design, divide the machining area according to the established difference model, determine the machining area, shape, and specification of the tool;

[0011] Step 4: Machining program preparation and simulation, complete the program preparation of each tool in sequence according to the machining area of the tool, and complete the trajectory simulation;

[0012] Step five, part processing, call the numerical control program to complete the part processing verification.

[0013] In the step three: the size of the tool is determined by the size of the smallest fillet measured in the groove type.

[0014] In step three: first process the rectangular area of the cavity, complete the groove depth processing by the tool, process the linear segment area on the right side of the split point by taking the split groove as the split point, then process the semicircular area, and finally the remaining area in the cavity is processed by the tool.

[0015] In step four: the cutting depth of each tool is not greater than 0.4mm, the tool feed speed is not greater than 0.15mm, the linear speed is not greater than 50m / min, and the cutting time of a single blade is not greater than 40min.

[0016] The advantages of the present application are: suitable for processing parts with complex groove structure, especially for narrow cavity structure of similar disc parts, which can effectively guarantee the machining precision and machining quality, and has wide applicability in the fields of aerospace, mechanical manufacturing, etc., adopts linkage turning, reasonable tool design and processing program, and measures for preventing chips for narrow structure, etc., improves the processing efficiency. According to the actual application, at present, 7.5 million yuan has been created, and the subsequent parts of the same family can realize the creation of more than 300 million yuan per year, which can realize the stable delivery of the family parts, has batch processing capacity, and meets the production demand. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The processing method flow chart of the present application;

[0018] Figure 2 The size analysis and measurement schematic diagram of the narrow cavity of the turbine disc in the case of the present application;

[0019] Figure 3 The difference model schematic diagram of the narrow cavity of the turbine disc in the case of the present application;

[0020] Figure 4 The tool structure schematic diagram in the case of the present application;

[0021] Figure 5 The processing area corresponding schematic diagram of the tool in the case of the present application. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0023] With a certain type of powder alloy turbine disc part of an aero-engine as an example, a narrow cavity linkage turning processing scheme is introduced, and the application will be further described below in combination with the drawings and examples.

[0024] 1) Process analysis of the narrow cavity of the part. The opening, depth, length, and size of the transition fillet of the cavity of the turbine disc are measured, which are 10.5 mm, 10.5 mm, 7.5 mm, and the minimum fillet size is R1.5 mm. The size of the fillet is determined by the minimum fillet, and in order to determine the size of the tool, the tool rigidity is improved as much as possible by selecting a large diameter tool, such as Figure 2 ;

[0025] 2) Draw the middle difference model of the narrow cavity of the part. According to the middle difference of the design drawing, the middle difference model is constructed, such as Figure 3 , which is prepared for tool design and program compilation;

[0026] 3) Tool structure design. According to the tool quantity, the same structure is as much as possible, and the linkage turning function is used to complete the design of the tool shape, such as Figure 4 , Figure 5 The units of the cavity size appearing below are all millimeters, and the following division and processing arrangement are carried out according to the groove processing area:

[0027] Region A is composed of a rectangle formed by the opening size of the cavity being 10.5 and the depth being 10.5, and this region is completed by tool 1.

[0028] Region B is composed of a rectangular part formed by the straight line segment area in the cavity length 7.5 (the right part of the transition groove R2 in the figure) to the groove depth 10.5, and this region is responsible for processing by tool 2.

[0029] Region D is formed by the semi-circular shape of the reverse transition fillet area in the cavity, and the area extending in the direction of the cavity depth with the radius of the tool selected in region D as the reference length, and the two parts together constitute the processing area of region D, which is completed by tool 4.

[0030] In addition to the above-mentioned regions A, B, and D, the remaining part is defined as region C, which is completed by tool 3.

[0031] 4) Processing program and simulation. Use computer to complete program trajectory generation, and for narrow structure, it is easy to occur extrusion, tool breaking, leading to the risk point of part out-of-tolerance. The tool is withdrawn from the part every 1-2 layers of deep cutting, and the iron chips on the narrow cavity of the part and the iron chips on the tool are cleaned using high pressure cooling, to ensure that the tool and the part have no iron chip phenomenon, according to the part material, the cutting depth of the tool is ≤0.4mm, the feed speed is ≤0.15mm, the linear speed is ≤50m / min, the cutting time of a single blade is ≤40min, and VERICUT is used for tool path simulation;

[0032] 5) Part processing. The part is clamped on the equipment, and the program is called to complete the whole processing of the part.

Claims

1. A method for precision machining of a disk-shaped workpiece in a narrow cavity by gang turning, characterized in that, It comprises the following steps: Step one, process analysis of narrow cavity of parts, measure the opening, depth, length, size of transition fillet of the cavity of parts; Step two, draw the difference model in the narrow cavity of parts, establish the difference model of narrow cavity of parts; Step three, tool structure design, divide the machining area according to the established difference model, determine the machining area, shape and specification of the tool; Step four, machining program preparation and simulation, complete the program preparation of each tool according to the machining area of the tool in turn, and complete the trajectory simulation; every 1-2 layers of deep cutting, the tool is withdrawn from the part, and the iron filings on the narrow cavity of the part and the tool are cleaned by using high pressure cooling liquid; Step five, part machining, call the numerical control program to complete the part machining verification; In step three: the specification of the tool is determined by the size of the smallest fillet measured in the groove type; In step three: first, the rectangular area of the cavity is machined, the groove depth is machined by the tool, the straight line segment area on the right side of the transition groove is machined, then the semicircular area is machined, and finally the remaining area in the cavity is machined by the tool; In step four: the cutting depth of each tool is not greater than 0.4mm, the tool feed speed is not greater than 0.15mm, the linear speed is not greater than 50m / min, and the cutting time of a single blade is not greater than 40min.

Images