A method for processing anti-rotation grooves of high-temperature alloy double-layer bearings

Abstract

A method for machining anti-rotation grooves of high-temperature alloy double-layer bearings comprises the following steps: rough milling the bottom bearing groove; first, positioning and pressing the process edge of the small diameter end of the bearing seat by using a tool, aligning the outer circle and end face of the large diameter end of the bearing seat, and ensuring that the circular runout is no more than 0.02mm; then, using a φ4mm milling cutter to move the cutter perpendicularly to the end face of the part along the axial direction from top to bottom, with a milling cutter speed of 1269r / min and a feed rate of 100mm / min; finishing milling the bottom bearing groove; using a φ4mm milling cutter to move the cutter in a manner of retracting the cutter once every 3mm feed, and the milling cutter The speed is 700r / min, and the feed rate is 80mm / min; rough milling of the upper bearing groove; use a φ3mm milling cutter to mill the anti-interference groove layer by layer, leaving a 0.1mm allowance for fine milling, the milling cutter speed is 1000r / min, and the feed rate is 40mm / min; fine milling of the upper bearing groove; use a φ3mm 28°~35° helix angle end mill perpendicular to the part axis for contour milling along the axial direction, removing a 0.1mm allowance, the milling cutter speed is 1300r / min, and the feed rate is 60mm / min.

Description

Technical Field

[0001] The invention belongs to the technical field of aviation engine parts manufacturing, and in particular relates to a method for processing an anti-rotation groove of a high-temperature alloy double-layer bearing. Background Art

[0002] As the performance requirements of aircraft engines become increasingly higher, the use of high-temperature alloys in aircraft engine components is also increasing. In particular, the rotor parts in aircraft engines are the main application components of high-temperature alloys. Taking GH4169 high-temperature alloy as an example, it has good comprehensive mechanical properties and excellent forging, heat treatment and welding process performance. However, it is also difficult to process. In particular, the tool is prone to sticking during the processing, which leads to severe hardening of the machined surface. The processed parts are prone to large deformation and distortion, and the processing accuracy is difficult to guarantee.

[0003] Taking the GH4169 high-temperature alloy double-layer bearing parts as an example, they are annular thin-walled structural parts, on which anti-rotation grooves need to be machined. Currently, this is mainly achieved by broaching, electrical discharge machining, or electrolytic machining. However, when broaching is used, due to the large cutting force generated, the parts are prone to broaching deformation, and different sizes of anti-rotation grooves require a separate set of broaches, and the manufacturing cost of broaches is high, resulting in poor economic efficiency of broaching. When electrical discharge machining is used, the contact area between the electrical discharge machining electrode and the part is large, resulting in a limited discharge area, uneven removal of allowances, and the machining length needs to be completed in sections and batches, which makes the parts prone to large deformation. In addition, electrical discharge machining will produce a remelting layer on the surface of the part, making the metal surface texture uneven and prone to microcracks, reducing the surface quality of the part. When electrolytic machining is used, the parts are difficult to clamp due to structural limitations of the parts, which also brings difficulties to the design and correction of the cathode and fixture of the electrolytic machining equipment. As a result, the preparation cycle of electrolytic machining is particularly long and the processing cost is the highest. Therefore, it is only suitable for the production of small batches of parts. Summary of the Invention

[0004] In response to the problems existing in the prior art, the present invention provides a method for processing anti-rotation grooves in high-temperature alloy double-layer bearings. By adopting an optimized milling processing method, the occurrence of tool sticking during the processing can be avoided, severe hardening of the processing surface can be avoided, and large deformation and distortion of the processed parts can be avoided, thereby ensuring the processing accuracy of the parts.

[0005] In order to achieve the above-mentioned object, the present invention adopts the following technical solution: a method for processing an anti-rotation groove of a high-temperature alloy double-layer bearing, comprising the following steps:

[0006] Step 1: Rough milling of the bottom bearing groove

[0007] First, use the tooling to position and tighten the process edge of the small diameter end of the bearing seat, align the outer circle and end face of the large diameter end of the bearing seat, and ensure that the circular runout is no more than 0.02mm. Then use a φ4mm milling cutter to move the cutter perpendicular to the end face of the part from top to bottom along the axial direction. The milling cutter speed is 1269r / min and the feed rate is 100mm / min.

[0008] Step 2: Fine milling of the bottom bearing groove

[0009] A φ4mm milling cutter was used, with a feed of 3mm followed by a retraction. The cutter speed was 700 rpm and the feed rate was 80 mm / min.

[0010] Step 3: Rough milling of the upper bearing groove

[0011] A φ3mm milling cutter is used to mill the anti-interference groove layer by layer, leaving a 0.1mm margin for fine milling. The milling cutter speed is 1000r / min and the feed rate is 40mm / min.

[0012] Step 4: Finish milling the upper bearing groove

[0013] A φ3mm end mill with a 28° to 35° helix angle is used to perform contour milling perpendicular to the axis of the part along the axial direction, removing a 0.1mm allowance. The milling cutter speed is 1300r / min and the feed rate is 60mm / min.

[0014] Beneficial effects of the present invention:

[0015] The method for processing the anti-rotation groove of the high-temperature alloy double-layer bearing of the present invention adopts an optimized milling processing method, which can avoid the occurrence of tool sticking during the processing, avoid severe hardening of the processing surface, avoid large deformation and distortion of the processed parts, and ensure the processing accuracy of the parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a diagram showing the positional relationship between the double-layer bearing anti-rotation groove and the bearing seat;

[0017] In the figure, 1 is the bearing seat, 2 is the double-layer bearing anti-rotation groove. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] In this embodiment, Figure 1 As shown, there are four double-layer bearing anti-rotation grooves 2 at the φ203mm inner hole 50mm away from the end face of the bearing seat 1. The width of the double-layer bearing anti-rotation groove 2 is 40mm, with a round chamfer of R1.5mm and a position accuracy of 0.1mm. The double-layer bearing anti-rotation groove 2 is on the arc surface of the φ203mm inner hole, and the material is unevenly distributed circumferentially.

[0020] A method for machining an anti-rotation groove of a high-temperature alloy double-layer bearing comprises the following steps:

[0021] Step 1: Rough milling of the bottom bearing groove

[0022] First, use the tooling to position and tighten the process edge of the small diameter end of the bearing seat, align the outer circle and end face of the large diameter end of the bearing seat 1, and ensure that the circular runout is no more than 0.02mm. Then, use a φ4mm milling cutter to move the cutter perpendicular to the end face of the part from top to bottom along the axial direction. The milling cutter speed is 1269r / min and the feed rate is 100mm / min. Specifically, because the double-layer bearing anti-rotation groove 2 is on the arc surface of the φ203mm inner hole, the material is unevenly distributed circumferentially, causing the tool to be under lateral force, so a small diameter milling cutter is used;

[0023] Step 2: Fine milling of the bottom bearing groove

[0024] A φ4mm milling cutter was used, with a feed of 3mm followed by a retraction. The milling cutter speed was 700 rpm and the feed rate was 80 mm / min. Specifically, due to the small chip space, chip removal was difficult, and the cutting fluid could not reach the entire milling cutter. If the cutting heat could not be discharged in time, it would cause heat accumulation and shorten the tool life. Therefore, an intermittent feed method was adopted.

[0025] Step 3: Rough milling of the upper bearing groove

[0026] A φ3mm milling cutter was used to mill the anti-interference groove layer by layer, leaving a 0.1mm margin for fine milling. The milling cutter speed was 1000r / min and the feed rate was 40mm / min. Specifically, the anti-interference groove had a depth of 1mm, a width of 1.5mm, and a chamfer of R1.5mm. Due to the problem of large tool vibration during machining, a layer-by-layer milling feed method was adopted.

[0027] Step 4: Finish milling the upper bearing groove

[0028] A φ3mm, 28°~35° helix angle end mill is used to perform contour milling perpendicular to the axis of the part in the axial direction, removing 0.1mm of allowance, the milling cutter speed is 1300r / min, and the feed rate is 60mm / min; specifically, before contour milling, it is necessary to first compile and simulate the complex surface CNC program in the simulation software to avoid interference between the part and the tool, optimize the cutting route and cutting parameters, and reduce the impact of tool vibration on the part; during the contour milling process, it is necessary to fully pour the cutting fluid to reduce the temperature rise, thereby inhibiting thermal deformation; the reason for using a 28°~35° helix angle end mill is to ensure that the tool does not weaken the teeth during long-term cutting, so as to reduce the thermal wear caused by the friction between the tool and the part and avoid a decrease in cutting force; using a larger speed and feed can not only improve processing efficiency, but also improve the surface quality of the part.

[0029] The solutions in the embodiments are not intended to limit the patent protection scope of the present invention. Any equivalent implementation or modification that does not deviate from the present invention is included in the patent scope of this case.

Claims

1. A method for processing anti-rotation grooves of high-temperature alloy double-layer bearings, characterized in that The steps include: Step 1: Rough milling of the bottom bearing groove First, use the tooling to position and tighten the process edge of the small diameter end of the bearing seat, align the outer circle and end face of the large diameter end of the bearing seat, and ensure that the circular runout is no more than 0.02mm. Then use a φ4mm milling cutter to move the cutter perpendicular to the end face of the part from top to bottom along the axial direction. The milling cutter speed is 1269r / min and the feed rate is 100mm / min. Step 2: Fine milling of the bottom bearing groove A φ4mm milling cutter was used, with a feed of 3mm followed by a retraction. The cutter speed was 700 rpm and the feed rate was 80 mm / min. Step 3: Rough milling of the upper bearing groove A φ3mm milling cutter is used to mill the anti-interference groove layer by layer, leaving a 0.1mm margin for fine milling. The milling cutter speed is 1000r / min and the feed rate is 40mm / min. Step 4: Finish milling the upper bearing groove A φ3mm end mill with a 28° to 35° helix angle is used to perform contour milling perpendicular to the axis of the part along the axial direction, removing a 0.1mm allowance. The milling cutter speed is 1300r / min and the feed rate is 60mm / min.

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