Turbine disc mortise side edge rounding model construction method

Abstract

The invention provides a turbine disc mortise side edge rounding model construction method. The turbine disc mortise side edge rounding model construction method comprises the steps that a part mortise structure model is constructed; building a model of the mortise structure according to design requirements; a mortise fillet is constructed according to the middle difference; performing mortise rounding establishment on a computer, and performing construction according to a median error; extracting the rounding surface in a sheet body mode to form a plurality of sheet bodies; rounding center virtual lines of the straight line segments are sequentially extracted along the groove type; constructing a rounding straight line of the straight line segment and other related lines; forming a trimmed rounded curved surface; constructing an envelope sweeping surface between adjacent straight line segments and trimming a curved surface; sewing the newly constructed swept surface to form a complete transition envelope surface by using a sewing function; sewing the middle-difference inverted round sheet body; sewing the rounding surface at one time along the groove shape to form a new rounding surface; and generating a program to finish numerical control machining of the part. The method has the advantages that the processing risk of over-cutting and under-cutting in the processing can be solved from the source, the high surface integrity of mortise side edge rounding is improved, 100% qualification is achieved, and higher value is created.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengine manufacturing, and in particular to a method for constructing a turbine disk tenon groove side rounding model. Background Art

[0002] As a key component of the rotor, the turbine disk works in harsh environments and is the component with the highest thermal and mechanical loads in the engine. In particular, the tongue and groove fillet structure is the main location for crack initiation and work failure, but it is very easy to undercut and overcut when modeled by conventional processing methods, and the shape control is extremely difficult. In order to achieve high surface integrity control and avoid tongue and groove fillet work failure, it has become a technical bottleneck and difficulty that needs to be solved urgently. Summary of the invention

[0003] The purpose of the present invention is to address the processing bottleneck problem of overcutting and undercutting that easily leads to scrapped parts during the chamfering of the side edges of the tenon groove of a turbine disk, and to invent a method for constructing a chamfering model for the side edges of the tenon groove of a turbine disk, thereby solving the processing risks of overcutting and undercutting from the source, improving the high surface integrity and 100% compliance of the chamfering of the side edges of the tenon groove, increasing the service life of the parts, and accurately mastering the core processing technology capabilities of this type of structure.

[0004] The present invention provides a method for constructing a turbine disk tenon groove side rounding model, comprising the following steps:

[0005] Step 1, construct the tenon and groove structure model of the parts; complete the model establishment of the tenon and groove structure according to the design requirements;

[0006] Step 2, constructing the mortise and tenon chamfer according to the mean difference; establishing the mortise and tenon chamfer on a computer and constructing it according to the mean difference;

[0007] Step 3, extracting the chamfered surface in a sheet form to form a plurality of sheets;

[0008] Step 4, sequentially extracting the rounded center virtual lines of the straight line segments along the groove;

[0009] Step 5, construct the chamfered straight line of the straight segment and other related lines; according to the chamfered center virtual line extracted in step 4, connect the upper end of the straight segment with one end of the virtual line on the same side along the direction of the groove to construct straight line 1; connect the lower end of the straight segment with one end of the virtual line on the same side along the direction of the groove to construct straight line 2; construct straight line 3 at a certain angle to straight line 2 and with the straight line segment length being the nominal value of the chamfer; construct straight line 4 at 90° to straight line 3, and complete the construction of all lines;

[0010] Step 6, constructing a straight line segment chamfering envelope sweeping surface and surface trimming; based on the straight line 4 constructed in step 5, a sweeping surface is established along the center virtual line of step 4; the chamfering surface of the original straight line portion is trimmed by using the trimming function to form a trimmed chamfered curved surface;

[0011] Step 7, constructing an envelope sweep surface and surface trimming between adjacent straight line segments; establishing a sweep surface along the groove direction for the fillet segments between the straight line segments according to step 6; using the trimming function to trim the chamfered surface of the original straight line portion to form a trimmed chamfered surface;

[0012] Step 8, stitching the newly constructed swept surface; complete the establishment of all swept surfaces according to steps 4 to 7, and use the stitching function to stitch the newly constructed swept surface to form a complete transition envelope surface;

[0013] Step 9, stitching the middle difference chamfered sheet body; stitching the chamfered surface formed in step 6 along the groove shape at one time to form a new chamfered surface;

[0014] Step 10, program generation; forming a NC program according to the envelope surface and chamfered surface newly generated in steps 8 and 9;

[0015] Step 11, output the NC program to complete the NC machining of the parts.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] It can solve the risk of overcutting and undercutting during processing from the source, and improve the high surface integrity and 100% qualification of the side chamfer of the tenon groove. The chamfering model of the side chamfer of the turbine disc tenon groove is constructed and CNC machining is completed. The chamfering appearance is complete, without overcutting or undercutting, and the precision requirements are met. It avoids the scrapping of parts due to overcutting or undercutting from the root, achieves 100% qualification in one-time processing, and creates higher value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0019] Figure 1 The present invention is a flow chart of a method for constructing a turbine disk tenon groove side rounding model.

[0020] Figure 2 It is a schematic diagram of the turbine disc tenon-and-groove structure model of the present invention;

[0021] Figure 3 It is a schematic diagram of the rounded side model of the tenon groove of the turbine disk of the present invention;

[0022] Figure 4 It is a schematic diagram of a virtual line of a chamfered center of a straight line segment sequentially extracted along a groove shape according to the present invention;

[0023] Figure 5 A schematic diagram of the positions of the rounded straight lines and other related lines constructed by the present invention;

[0024] Figure 6A schematic diagram of constructing a straight line segment chamfering envelope sweeping surface and a curved surface trimming according to the present invention;

[0025] Figure 7 A schematic diagram of constructing a rounded swept surface QS1 between straight line segments according to the present invention;

[0026] Figure 8 A schematic diagram of constructing a rounded extension surface QS2 between straight line segments according to the present invention;

[0027] Fig. 9 A schematic diagram of constructing a rounded extension surface QS3 between straight line segments according to the present invention;

[0028] Fig.10 A schematic diagram of constructing a rounded transition envelope swept surface QS4 between straight line segments according to the present invention;

[0029] Fig.11 A schematic diagram of constructing rounded corners NEW2 between straight line segments of the present invention;

[0030] Fig.12 A schematic diagram of a complete transition envelope surface SP1 constructed for the part of the present invention;

[0031] Fig.13 It is a schematic diagram of the new rounded surface SP2 of the part of the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further explained below in conjunction with specific implementation plans, but the present invention is not limited thereto. The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the restrictive conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0033] The present invention aims at the processing risk of overcutting and undercutting in the rounding process of the side edge of the tenon groove of the turbine disk, which leads to the scrapping of the parts due to over-tolerance. In order to improve the high surface integrity control and 100% qualification of the side edge of the tenon groove and improve the service life, a new model construction method for the side edge of the tenon groove of the turbine disk is invented, which solves the processing risk of overcutting and undercutting in the processing from the source, improves the high surface integrity and 100% qualification of the side edge of the tenon groove. Taking a certain type of turbine disk part of an aircraft engine as an example, a plan for constructing a model for the side edge of the tenon groove is formulated, and the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0034] The overall process is as follows Figure 1 shown.

[0035] 1) Construct the model of the mortise and tenon structure of the parts. Complete the modeling of the mortise and tenon structure according to the design requirements, such as Figure 2 ;

[0036] 2) Construct the chamfer of the mortise and tenon according to the mean difference. Construct the chamfer of the mortise and tenon on the computer and construct it according to the mean difference R0.55mm. Figure 3 ;

[0037] 3) Extract the chamfered surface in a sheet form to form multiple sheets. Extract the chamfered surface along the groove shape in sequence on the computer to form multiple extraction surfaces;

[0038] 4) Extract the rounding center virtual line of the straight line segment in sequence along the groove shape. Figure 4 In the straight line segment fillet 1 and straight line segment fillet 2, select the Extract Virtual Curve command to form the fillet center virtual curves 1 and 2, as shown in Figure 4 ;

[0039] 5) Construct the straight line and other related lines. Take the straight line 1 in step 4 as an example to establish all the straight lines. You can use this method to complete the establishment of all the related lines of the straight line arc. First, select the virtual line 1 of the center of the rounding to extract. Figure 5 As shown, the upper end of the straight line segment is connected to the same side virtual line along the direction of the groove to construct the straight line L1; the lower end of the straight line segment is connected to the same side virtual line along the direction of the groove to construct the straight line L2; the straight line L3 is constructed at 10°-15° with the straight line L2, coplanar with the two straight lines L1 and L2, located between L1 and L2, and the length is the nominal value of the fillet, i.e. R0.55mm, in order to construct the straight line L4 in preparation for the subsequent establishment of the transition envelope surface; the straight line L4 is constructed at 90° with the straight line L3, coplanar with the two straight lines L1 and L2, and the length is 0.4mm-0.5mm. It is recommended to select the range of 75%-100% of the nominal value of the mean difference fillet length R0.55mm, which satisfies a certain transition distance, and completes the construction of all straight lines, as shown in FIG. Figure 5 ;

[0040] 6) Construct the straight line segment chamfering envelope sweeping surface and surface trimming. Based on the straight line L4 constructed in step 5, a sweeping surface is established with the chamfering center virtual line 1 as the direction to form a sweeping surface S1. The original straight line chamfering surface is trimmed using the trimming function to form a trimmed chamfering surface NEW1, as shown in FIG. Figure 6 , complete the trimming of all straight line segment filleting envelope sweeping surfaces and original filleting surfaces in sequence;

[0041] 7) Construct the envelope swept surface and curved surface trimming between adjacent straight line segments. After all the swept surfaces and fillet surfaces are trimmed along the groove direction, take the fillet part between the straight line fillet 1 and the straight line fillet 2 as an example to establish the envelope swept surface of the fillet surface between the two, with B1 as the section line and B2 as the sweep line to form the swept surface QS1, and form the B3 line, as shown in the figure. Figure 7 The chamfered surface formed by the chamfered part of the two straight line segments can directly obtain endpoints 1 and 2, which are connected with the two ends of the formed B3 line to form straight lines B5 and B4 respectively. With B3 as the section line and B5 and B4 as the guide lines, the extended surface QS2 is formed. Figure 8 , and use trimming to trim the inner part of the rounded surface to form a trimmed surface QS3, and form B6, such as Fig. 9 ; Select B8 and B7 as section lines, B6 as guide line, and establish transition envelope sweep surface QS4, as shown Fig.10 ; Use the trimming function to trim the original straight line part of the chamfered surface to form the trimmed chamfered surface NEW2, such as Fig.11 ; Follow this step to complete the trimming of the envelope sweep surface and chamfered surface between all adjacent straight line segments;

[0042] 8) Suture the newly constructed swept surface. Complete the establishment of all swept surfaces according to steps 4 to 7, and use the sew function to sew the newly constructed swept surface to form a complete transition envelope surface SP1, as shown in FIG. Fig.12 ;

[0043] 9) Stitching the middle difference rounded sheet body; Stitching the rounded surface formed in step 6 along the groove once to form a new rounded surface SP2, such as Fig.13 ;

[0044] 10) Program generation. Use a computer to select the surfaces SP1 and SP2 in steps 8 and 9 and generate a NC program;

[0045] 11) Output the CNC program to complete the CNC machining of parts.

[0046] Matters not covered by the present invention are known technologies.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for constructing a turbine disk tenon groove side rounding model, characterized in that: The following steps are involved: Step 1, construct the tenon and groove structure model of the parts; complete the model establishment of the tenon and groove structure according to the design requirements; Step 2, construct the mortise and tenon chamfer according to the median difference; The mortise and tenon chamfering is established on the computer and constructed according to the mean difference; Step 3, extracting the chamfered surface in a sheet form to form a plurality of sheets; Step 4, sequentially extracting the rounded center virtual lines of the straight line segments along the groove; Step 5, construct the straight line segment rounding line and other related lines; Step 6, constructing the straight line segment filleting envelope sweeping surface and surface trimming; Step 7, constructing the envelope sweeping surface and surface trimming between adjacent straight line segments; Step 8, stitching the newly constructed swept surface; complete the establishment of all swept surfaces according to steps 4 to 7, and use the stitching function to stitch the newly constructed swept surface to form a complete transition envelope surface; Step 9, stitching the middle difference chamfered sheet body; stitching the chamfered surface formed in step 6 along the groove shape at one time to form a new chamfered surface; Step 10, program generation; forming a NC program according to the envelope surface and chamfered surface newly generated in steps 8 and 9; Step 11, output the NC program to complete the NC machining of the parts.

2. The method for constructing a turbine disk tenon groove side rounding model according to claim 1, characterized in that: The step 5 is to construct a chamfered straight line of a straight segment and other related lines; according to the chamfered center virtual line extracted in step 4, the upper end of the straight line segment is connected with one end of the virtual line on the same side along the direction of the groove to construct a straight line 1; the lower end of the straight line segment is connected with one end of the virtual line on the same side along the direction of the groove to construct a straight line 2; a straight line 3 is constructed at a certain angle to the straight line 2 and the length of the straight line segment is the nominal value of the chamfer; a straight line 4 is constructed at 90° to the straight line 3 to complete the construction of all lines.

3. The method for constructing a turbine disk tenon groove side rounding model according to claim 1, characterized in that: The step 6 is to establish a swept surface based on the straight line 4 constructed in step 5, along the center virtual line of step 4 as the direction; and use the trimming function to trim the chamfered surface of the original straight line to form a trimmed chamfered surface.

4. The method for constructing a turbine disk tenon groove side rounding model according to claim 1, characterized in that: In the step 7, a sweep surface is established along the groove direction by using the fillet segments between the straight line segments according to the step 6; and the chamfered surface of the original straight line portion is trimmed by using the trimming function to form a trimmed chamfered curved surface.

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