A milling method for dovetail groove type wheel groove of rotor

Abstract

A milling method for dovetail groove wheel grooves of rotors. The present invention relates to the technical field of wheel groove processing. The present invention is to solve the problem that the processing of existing dovetail groove wheel grooves is difficult to achieve. The present invention comprises the following steps: selecting a roughing milling cutter I, a roughing milling cutter II, a semi-finishing end milling cutter, a semi-finishing milling cutter I, a semi-finishing milling cutter II, a finishing milling cutter and a finishing end milling cutter of corresponding sizes according to the dovetail groove profile size of the wheel groove, and selecting a machine tool with corresponding parameters at the same time; milling out the middle rectangular area of ​​the groove to be processed; milling out the bottom arc area of ​​the groove to be processed; milling out the inclined surface areas on both sides of the top of the groove to be processed; milling out the upper area of ​​the notch, the lower area of ​​the notch and the arc area of ​​the groove bottom of the groove to be processed; milling out the arc areas on both sides of the inside of the groove to be processed; milling the inner groove profile of the groove to be processed; milling the upper groove profile of the groove to be processed. The present invention is used for the milling of wheel grooves.

Description

Technical Field

[0001] The invention relates to the technical field of wheel groove processing, and in particular to a milling processing method for a dovetail groove type wheel groove of a rotor. Background Art

[0002] The wheel groove profile of the 300MW gas turbine frequency test rotor in heavy-duty gas turbines is the same as that of heavy-duty gas turbines, which is a dovetail groove structure. This structure is usually used on the wheel disc and is processed by broaching; however, this structure cannot be processed by broaching on the whole forged rotor, and an effective processing method has not been found to achieve the processing of this dovetail groove line wheel groove. Therefore, the processing of rotor wheel grooves is difficult to achieve, and the processing method of wheel grooves needs to be solved urgently. Summary of the invention

[0003] In order to solve the problem that the existing dovetail groove type linear wheel groove is difficult to process, the present invention further proposes a milling method for the dovetail groove type wheel groove of a rotor.

[0004] The technical solution adopted by the present invention to solve the above technical problems is:

[0005] A milling method for a dovetail groove of a rotor comprises the following steps:

[0006] Step 1. Select the tool: According to the dovetail groove profile size of the wheel groove, select the corresponding sizes of rough milling cutter I, rough milling cutter II, semi-finishing end milling cutter, semi-finishing milling cutter I, semi-finishing milling cutter II, finishing milling cutter and finishing end milling cutter, and select the machine tool with the corresponding parameters;

[0007] Step 2: First rough machining: Install the rough milling cutter I on the spindle of the machine tool, mill out the middle rectangular area of ​​the groove to be machined, and remove the rough milling cutter I after completion;

[0008] Step 3: Second roughing: Install the roughing cutter II on the machine tool spindle, mill out the bottom arc area of ​​the groove to be processed, and remove the roughing cutter II after completion;

[0009] Step 4: Semi-finishing end milling: Install the semi-finishing end mill on the machine tool spindle, mill out the inclined surface areas on both sides of the top of the groove to be processed, and remove the semi-finishing end mill after completion;

[0010] Step 5, first semi-finishing: install the semi-finishing milling cutter I on the main spindle of the machine tool, mill out the upper area of ​​the slot, the lower area of ​​the slot and the arc area of ​​the slot bottom of the slot to be processed, and remove the semi-finishing milling cutter I after completion;

[0011] Step 6: Second semi-finishing: Install the semi-finishing milling cutter II on the machine tool spindle, mill out the arc areas on both sides of the inner side of the groove to be processed, and remove the semi-finishing milling cutter II after completion;

[0012] Step 7: Finishing: Install the finishing milling cutter on the machine tool spindle, mill the inner line of the groove to be processed, and remove the finishing milling cutter after completion;

[0013] Step 8. Precision end milling: Install the precision end milling cutter on the machine tool spindle and mill the upper profile of the slot to be processed. This completes the milling of the slot to be processed.

[0014] Furthermore, the blade shapes of the roughing cutter I, the roughing cutter II, the semi-finishing end mill, the semi-finishing cutter I and the semi-finishing cutter II are all wavy blades.

[0015] Furthermore, the teeth of the roughing cutter I, roughing cutter II, semi-finishing cutter I, semi-finishing cutter II and finishing cutter are all four-tooth spiral structures.

[0016] Furthermore, the teeth of the semi-finishing end mill and the finishing end mill are both eight-tooth spiral structures.

[0017] Furthermore, the front angles of the finishing milling cutter and the finishing end milling cutter are both 0°.

[0018] Furthermore, the surfaces of the roughing cutter I, roughing cutter II, semi-finishing end milling cutter, semi-finishing cutter I, semi-finishing cutter II, finishing cutter and finishing end milling cutter head are all provided with a coating.

[0019] Furthermore, the roughing cutter I, roughing cutter II, semi-finishing end milling cutter, semi-finishing cutter I, semi-finishing cutter II, finishing cutter and finishing end milling cutter head are all made of ASP2030 powder metallurgy high-speed steel.

[0020] Furthermore, the tool holders of the roughing cutter I, roughing cutter II, semi-finishing end milling cutter, semi-finishing cutter I, semi-finishing cutter II, finishing cutter and finishing end milling cutter are all ISO40 tool holders.

[0021] Furthermore, the milling area of ​​the rough milling cutter I in the step two is 61.5% of the area of ​​the groove to be processed; the milling area of ​​the rough milling cutter II in the step three is 0.03% of the area of ​​the groove to be processed; the milling area of ​​the semi-finishing end mill in the step four is 6.57% of the area of ​​the groove to be processed; the milling area of ​​the semi-finishing milling cutter I in the step five is 15% of the area of ​​the groove to be processed; the milling area of ​​the semi-finishing milling cutter II in the step six is ​​15% of the area of ​​the groove to be processed; the milling area of ​​the finishing milling cutter in the step seven is 1.6% of the area of ​​the groove to be processed; the milling area of ​​the finishing end mill in the step eight is 0.3% of the area of ​​the groove to be processed.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention provides a milling processing method for a dovetail groove type wheel groove of a rotor. The processing method can smoothly complete the processing of the rotor wheel groove with high processing accuracy, fill the blank of dovetail groove type linear wheel groove processing, solve practical production problems, and ensure smooth processing of the wheel groove. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the dovetail groove profile line in the present invention;

[0025] Figure 2 is a processing schematic diagram in step 2 of the present invention, wherein the section line area is the middle rectangular area 9;

[0026] Figure 3 It is a front view of the roughing cutter I1 in the present invention;

[0027] Figure 4 yes Figure 3 Left view of;

[0028] Figure 5 is a processing schematic diagram in step three of the present invention, wherein the section line area is the bottom arc area 10;

[0029] Figure 6 It is a front view of the roughing cutter II2 of the present invention;

[0030] Figure 7 yes Figure 6 Left view of;

[0031] Figure 8 is a processing schematic diagram in step 4 of the present invention, wherein the section line area is the inclined surface area 11;

[0032] Fig. 9 It is a front view of the semi-finishing end mill 3 of the present invention;

[0033] Fig.10 yes Fig. 9 Left view of;

[0034] Fig.11 1 is a processing schematic diagram in step 5 of the present invention, wherein the section line area is the notch upper area 12, the notch lower area 13 and the notch bottom arc area 14;

[0035] Fig.12 It is a front view of the semi-finishing milling cutter I4 in the present invention;

[0036] Fig.13 yes Fig.12 Left view of;

[0037] Fig.14 is a processing schematic diagram in step six of the present invention, wherein the section line area is the arc area 15;

[0038] Fig.15 It is a front view of the semi-finishing milling cutter II5 of the present invention;

[0039] Fig.16 yes Fig.15 Left view of;

[0040] Fig.17 It is a processing schematic diagram in step seven of the present invention;

[0041] Fig.18 It is a front view of the fine milling cutter 6 in the present invention;

[0042] Fig.19 yes Fig.18 Left view of;

[0043] Fig. 20 It is a processing schematic diagram in step eight of the present invention;

[0044] Fig.21 It is a front view of the fine end milling cutter 7 of the present invention;

[0045] Fig. 22 yes Fig.21 Left view of . DETAILED DESCRIPTION

[0046] Specific implementation method 1: Combination Figures 1 to 22 The present embodiment is described as follows. The present embodiment is a milling method for a dovetail groove of a rotor, characterized in that the method comprises the following steps:

[0047] Step 1, select the tool: according to the dovetail groove profile size of the wheel groove, select the corresponding size of the rough milling cutter I1, rough milling cutter II2, semi-finishing end milling cutter 3, semi-finishing milling cutter I4, semi-finishing milling cutter II5, finishing milling cutter 6 and finishing end milling cutter 7, and select the machine tool with the corresponding parameters;

[0048] Step 2: First rough machining: Install the rough milling cutter I1 on the main spindle of the machine tool, mill out the middle rectangular area 9 of the groove 8 to be machined, and remove the rough milling cutter I1 after completion;

[0049] Step 3, second roughing: install the roughing cutter II2 on the main spindle of the machine tool, mill out the bottom arc area 10 of the groove 8 to be processed, and remove the roughing cutter II2 after completion;

[0050] Step 4, semi-finishing end milling: install the semi-finishing end milling cutter 3 on the main spindle of the machine tool, mill out the inclined surface areas 11 on both sides of the top of the groove 8 to be processed, and remove the semi-finishing end milling cutter 3 after completion;

[0051] Step 5, first semi-finishing: install the semi-finishing milling cutter I4 on the main spindle of the machine tool, mill out the upper area 12 of the slot, the lower area 13 of the slot and the arc area 14 of the slot bottom of the slot type 8 to be processed, and remove the semi-finishing milling cutter I4 after completion;

[0052] Step 6, second semi-finishing: install the semi-finishing milling cutter II5 on the main spindle of the machine tool, mill out the arc area 15 on both sides of the inner side of the groove 8 to be processed, and remove the semi-finishing milling cutter II5 after completion;

[0053] Step 7, finishing: install the finishing milling cutter 6 on the main spindle of the machine tool, mill the inner groove line 16 of the groove 8 to be processed, and remove the finishing milling cutter 6 after completion;

[0054] Step 8, fine end milling: install the fine end milling cutter 7 on the main spindle of the machine tool, and mill the upper profile line 17 of the slot to be processed 8, thus completing the milling process of the slot to be processed 8.

[0055] The maximum depth D of the dovetail groove profile reaches 65.74mm, and the maximum outer diameter is φ99.6mm. In order to ensure the smooth progress of processing, the cutting allowance should be reasonably distributed, and 7 cutters are used after comprehensive consideration of various factors, namely two rough milling cutters, two semi-finishing milling cutters, one fine milling cutter, one semi-finishing end milling cutter, and one fine end milling cutter.

[0056] Specific implementation method 2: Combination Figures 1 to 22 In this embodiment, the roughing cutter I1, roughing cutter II2, semi-finishing end mill 3, semi-finishing cutter I4 and semi-finishing cutter II5 described in this embodiment are all wave-shaped. The undisclosed technical features in this embodiment are the same as those in the first embodiment.

[0057] Structurally, both the roughing cutter and the semi-finishing cutter use wavy edges, which greatly reduces the cutting resistance and makes cutting easier.

[0058] Specific implementation method three: Combination Figures 1 to 22 To illustrate this embodiment, the teeth of the roughing cutter I1, roughing cutter II2, semi-finishing cutter I4, semi-finishing cutter II5 and finishing cutter 6 in this embodiment are all four-tooth helical structures. The undisclosed technical features in this embodiment are the same as those in the first embodiment.

[0059] Specific implementation method four: Combination Figures 1 to 22 To explain this embodiment, the teeth of the semi-finishing end mill 3 and the finishing end mill 7 described in this embodiment are both eight-tooth spiral structures. The undisclosed technical features in this embodiment are the same as those in the first embodiment.

[0060] Specific implementation method five: Combination Figures 1 to 22To illustrate this embodiment, the front angles of the fine milling cutter 6 and the fine end milling cutter 7 in this embodiment are both 0°. The undisclosed technical features in this embodiment are the same as those in the first embodiment.

[0061] The front end surfaces of the cutter heads of the roughing milling cutter II2, the semi-finishing milling cutter I4, the semi-finishing milling cutter II5 and the finishing milling cutter 6 are all arc-shaped curved surfaces.

[0062] Specific implementation method six: Combination Figures 1 to 22 To explain this embodiment, the surfaces of the cutter heads of the roughing cutter I1, roughing cutter II2, semi-finishing end mill 3, semi-finishing cutter I4, semi-finishing cutter II5, finishing cutter 6 and finishing end mill 7 in this embodiment are all provided with coatings. The undisclosed technical features in this embodiment are the same as those in the specific embodiments 1, 2, 3, 4 or 5.

[0063] Specific implementation method seven: Combination Figures 1 to 22 To illustrate this embodiment, the cutter heads of the roughing cutter I1, roughing cutter II2, semi-finishing end mill 3, semi-finishing cutter I4, semi-finishing cutter II5, finishing cutter 6 and finishing end mill 7 in this embodiment are all made of ASP2030 powder metallurgy high-speed steel. The undisclosed technical features in this embodiment are the same as those in the sixth embodiment.

[0064] For the rotor material 26Cr2Ni4MoV, the wheel groove milling cutter is made of ASP2030 powder metallurgy high-speed steel.

[0065] Specific implementation method eight: Combination Figures 1 to 22 To illustrate this embodiment, the tool holders of the roughing cutter I1, roughing cutter II2, semi-finishing end mill 3, semi-finishing cutter I4, semi-finishing cutter II5, finishing cutter 6 and finishing end mill 7 in this embodiment are all ISO40 tool holders. The undisclosed technical features in this embodiment are the same as those in the specific embodiments one, two, three, four or five.

[0066] Due to the large size of the profile, in order to ensure smooth cutting and transmit greater torque during processing, the tool is installed on the machine tool spindle and the tool holder uses ISO40.

[0067] Specific implementation method nine: Combination Figures 1 to 22To explain this embodiment, the milling area of ​​the rough milling cutter I1 in step 2 of this embodiment is 61.5% of the area of ​​the groove 8 to be processed; the milling area of ​​the rough milling cutter II2 in step 3 is 0.03% of the area of ​​the groove 8 to be processed; the milling area of ​​the semi-finishing end milling cutter 3 in step 4 is 6.57% of the area of ​​the groove 8 to be processed; the milling area of ​​the semi-finishing milling cutter I4 in step 5 is 15% of the area of ​​the groove 8 to be processed; the milling area of ​​the semi-finishing milling cutter II5 in step 6 is 15% of the area of ​​the groove 8 to be processed; the milling area of ​​the finishing milling cutter 6 in step 7 is 1.6% of the area of ​​the groove 8 to be processed; the milling area of ​​the finishing end milling cutter 7 in step 8 is 0.3% of the area of ​​the groove 8 to be processed. The undisclosed technical features in this embodiment are the same as those in the specific embodiment 1.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A milling method for a dovetail groove of a rotor, characterized in that: The method comprises the following steps: Step 1, select tools: select roughing cutter I (1), roughing cutter II (2), semi-finishing end milling cutter (3), semi-finishing cutter I (4), semi-finishing cutter II (5), finishing cutter (6) and finishing end milling cutter (7) of corresponding sizes according to the dovetail groove profile of the wheel groove, and select a machine tool with corresponding parameters; Step 2, first rough machining: install the rough milling cutter I (1) on the main spindle of the machine tool, mill out the middle rectangular area (9) of the groove (8) to be machined, and remove the rough milling cutter I (1) after completion; Step 3, second roughing: install the roughing cutter II (2) on the main spindle of the machine tool, mill out the bottom arc area (10) of the groove (8) to be processed, and remove the roughing cutter II (2) after completion; Step 4, semi-finishing end milling: install the semi-finishing end milling cutter (3) on the main spindle of the machine tool, mill out the inclined surface areas (11) on both sides of the top of the groove (8) to be processed, and remove the semi-finishing end milling cutter (3) after completion; Step 5, first semi-finishing: install the semi-finishing milling cutter I (4) on the main spindle of the machine tool, mill out the upper area (12) of the slot, the lower area (13) of the slot and the arc area (14) of the slot bottom of the slot type (8) to be processed, and remove the semi-finishing milling cutter I (4) after completion; Step 6: Second semi-finishing: install the semi-finishing milling cutter II (5) on the main spindle of the machine tool, mill out the arc areas (15) on both sides of the inner side of the groove (8) to be processed, and remove the semi-finishing milling cutter II (5) after completion; Step 7, finishing: install the finishing milling cutter (6) on the main spindle of the machine tool, mill the inner groove profile (16) of the groove type (8) to be processed, and remove the finishing milling cutter (6) after completion; Step 8, fine end milling: Install the fine end milling cutter (7) on the main spindle of the machine tool to mill the upper profile line (17) of the slot to be processed (8), thus completing the milling process of the slot to be processed (8).

2. A milling method for a dovetail groove of a rotor according to claim 1, characterized in that: The cutting edges of the roughing cutter I (1), the roughing cutter II (2), the semi-finishing end mill (3), the semi-finishing cutter I (4) and the semi-finishing cutter II (5) are all wavy cutting edges.

3. A milling method for a dovetail groove of a rotor according to claim 1, characterized in that: The teeth of the roughing cutter I (1), the roughing cutter II (2), the semi-finishing cutter I (4), the semi-finishing cutter II (5) and the finishing cutter (6) are all of four-tooth spiral structure.

4. A milling method for a dovetail groove of a rotor according to claim 1, characterized in that: The teeth of the semi-finishing end mill (3) and the finishing end mill (7) are both eight-tooth spiral structures.

5. A milling method for a dovetail groove of a rotor according to claim 1, characterized in that: The front angles of the finishing milling cutter (6) and the finishing end milling cutter (7) are both 0°.

6. A milling method for a dovetail groove of a rotor according to claim 1, 2, 3, 4 or 5, characterized in that: The surfaces of the tool heads of the roughing cutter I (1), the roughing cutter II (2), the semi-finishing end mill (3), the semi-finishing cutter I (4), the semi-finishing cutter II (5), the finishing cutter (6) and the finishing end mill (7) are all provided with coatings.

7. A milling method for a dovetail groove of a rotor according to claim 6, characterized in that: The cutter heads of the roughing cutter I (1), roughing cutter II (2), semi-finishing end mill (3), semi-finishing cutter I (4), semi-finishing cutter II (5), finishing cutter (6) and finishing end mill (7) are all made of ASP2030 powder metallurgy high-speed steel.

8. A milling method for a dovetail groove of a rotor according to claim 1, 2, 3, 4 or 5, characterized in that: The tool handles of the roughing cutter I (1), roughing cutter II (2), semi-finishing end milling cutter (3), semi-finishing cutter I (4), semi-finishing cutter II (5), finishing cutter (6) and finishing end milling cutter (7) are all ISO40 tool handles.

9. A milling method for a dovetail groove of a rotor according to claim 1, characterized in that: The milling area of ​​the roughing cutter I (1) in step 2 is 61.5% of the area of ​​the groove (8) to be processed; the milling area of ​​the roughing cutter II (2) in step 3 is 0.03% of the area of ​​the groove (8) to be processed; the milling area of ​​the semi-finishing end mill (3) in step 4 is 6.57% of the area of ​​the groove (8) to be processed; the milling area of ​​the semi-finishing milling cutter I (4) in step 5 is 15% of the area of ​​the groove (8) to be processed; the milling area of ​​the semi-finishing milling cutter II (5) in step 6 is 15% of the area of ​​the groove (8) to be processed; the milling area of ​​the finishing mill (6) in step 7 is 1.6% of the area of ​​the groove (8) to be processed; and the milling area of ​​the finishing end mill (7) in step 8 is 0.3% of the area of ​​the groove (8) to be processed.

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