Machining method of flexible bolt

Abstract

The machining method of the flexible bolt comprises the following steps: numerical turning: grooving; dual annealing: ensuring that the strength sigma b is equal to 980-1180 MPa; bench work: straightening the product; stress relief annealing: eliminating the residual stress of the product; turning: firstly, drilling a central hole; lathing a clamping process section; clamping the process section by adopting a special spherical jacket, and turning the outer circle by clamping and jacking; centerless grinding: grinding an outer circle; stress relief annealing: eliminating the residual stress of the product; the original center hole is removed, and then center holes are drilled in the two ends of the product again; turning: ejecting center holes at two ends by adopting an ejector pin, and turning an outer circle; centerless grinding: grinding the outer circle to the required size of the product; general turning is conducted, specifically, sharp corners of the grooves are polished through polishing cotton; the diameter of a rolled thread blank and the diameter of a square blank are turned; numerical milling: milling, pulling and twisting four corners; burrs are removed, wherein the burrs in the four directions are removed; thread rolling: rolling threads at two ends; performing fluorescence flaw detection; anodizing is conducted; the anodized layers on the two end faces are removed; preparing a mark: preparing a mark by adopting an electrolysis method; performing total inspection; and warehousing.

Description

Technical Field

[0001] The invention relates to a method for processing a flexible bolt, and belongs to the technical field of manufacturing mechanical processing parts. Background Art

[0002] Flexible bolts are made of titanium alloy, which has the advantages of low density, light weight, high strength and good corrosion resistance. They are suitable for occasions with weight reduction requirements and corrosive environments.

[0003] Therefore, flexible bolts are widely used in aircraft engines, with high demand, frequent production and large quantities.

[0004] Due to the flexible bolts, such as Figure 1 As shown, the outer diameter is small and the tolerance requirement is high, the length is long and the form and position tolerance runout requirement is high, so the processing is difficult and the size and form and position tolerances are not easy to guarantee.

[0005] When using traditional processing methods, the bolts have a small outer diameter, a long length, and high form and position tolerances, which places high demands on the precision of the processing equipment and the skill level of the operator. In addition, it is difficult to guarantee the size and shape and position tolerances of the product after processing, so the scrap rate is high, which increases the product production cycle and manufacturing costs. Summary of the invention

[0006] The present invention aims to solve the technical problem that the bolt has a small outer diameter, a long length, and high form and position tolerance requirements, which places high requirements on the accuracy of processing equipment and the skill level of operators. It is difficult to ensure the size and form and position tolerance of the product after processing, resulting in a high scrap rate, increased product production cycle and manufacturing cost.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions: A method for processing a flexible bolt comprises the following steps: 1) Numbering car: groove engraving, used for vertical hanging for heat treatment; 2) Double annealing: hang vertically to ensure that the strength meets σb=980~1180MPa; 3) Fitter: Straighten the product to ensure that the straightness is within the specified range; 4) Stress relief annealing: eliminate residual stress of products; 5) Turning: First drill the center hole; then turn the clamping process section; then use a special spherical clamping sleeve to clamp the process section, one clamp and one top turn the outer circle, leaving a double-sided margin of 1.7mm; 6) Centerless grinding: Grinding the outer circle, leaving a 1.4mm margin on both sides; 7) Stress relief annealing: eliminate residual stress of products; 8) Turning: Remove the original center hole and then re-drill the center holes at both ends of the product; 9) Turning: Use a pin to push the center holes at both ends, turn the outer circle, and leave a double-sided margin of 0.2mm; 10) Centerless grinding: grinding the outer circle to the required size of the product; 11) General lathe: Use polishing cotton to polish the sharp corners of the groove to ensure smooth transition; 12) Counting and turning: turning the diameter of the thread rolling blank and the diameter of the square blank; 13) Milling: Milling wrench and twisting square; 14) Deburring: remove burrs on all sides; 15) Thread rolling: rolling threads at both ends; 16) Fluorescent flaw detection; 17) Anodizing; 18) Counting and lathing: remove the anodized layer on both ends to ensure the overall length is qualified; 19) Label preparation: Electrolysis method is used for label preparation; 20) General inspection; 21) Storage.

[0008] The beneficial effects of adopting the above technical solution are: The flexible bolts processed by the present invention have small size and shape and position tolerances; the processing method is simple and feasible, and does not require high skill levels of processing personnel; the processing quality is stable and reliable, the product qualification rate is high, and the scrap rate and production cycle are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a schematic diagram of the flexible bolt structure. DETAILED DESCRIPTION

[0010] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0011] For this flexible bolt, it is particularly important to develop a reasonable and feasible processing method with stable and reliable processing quality.

[0012] A processing method for a flexible bolt, according to the flexible bolt Figure 1 The dimensions and geometric tolerances shown are used as the basis for formulating this processing method.

[0013] The processing method of the flexible bolt is as follows: 1) Numbering machine: groove engraving (for vertical hanging for heat treatment); 2) Double annealing: ensure that the strength meets σb = 980 ~ 1180MPa (vertical hanging); 3) Fitter: Straighten the product to ensure that the straightness is within the specified range; 4) Stress relief annealing: eliminate residual stress of products; 5) Turning: ① Drilling the center hole; ② Turning the clamping process section; ③ Using a special spherical sleeve to clamp the process section, one clamp and one push to turn the outer circle (leave 1.7mm for double-sided allowance).

[0014] 6) Centerless grinding: grinding the outer circle (leave 1.4mm on both sides); 7) Stress relief annealing: eliminate residual stress of products; 8) Turning: Remove the original center hole and then re-drill the center holes at both ends of the product; 9) Turning: Use a pin to push the center holes at both ends and turn the outer circle (leave 0.2mm for double-sided margin); 10) Centerless grinding: grinding the outer circle to the required size of the product; 11) General lathe: Use polishing cotton to polish the sharp corners of the groove to ensure smooth transition; 12) Counting and turning: turning the diameter of the thread rolling blank and the diameter of the square blank; 13) Milling: Milling wrench and twisting square; 14) Deburring: remove burrs on all sides; 15) Thread rolling: rolling threads at both ends; 16) Fluorescent flaw detection; 17) Anodizing; 18) Counting and lathing: remove the anodized layer on both ends to ensure the overall length is qualified; 19) Label preparation: Electrolysis method is used for label preparation; 20) General inspection; 21) Storage; Compared with the traditional processing method, the present invention can bring the following beneficial effects: 1. The processing method is reasonable and feasible; 2. The processing quality is stable and reliable, the product qualification rate is high, and the production cost and production cycle are reduced; 3. The processing technology is simple and feasible, and does not require high skill levels from the processing personnel.

Claims

1. A method for processing a flexible bolt, characterized in that: It includes the following steps: 1) Numbering machine: groove engraving, used for vertical hanging for heat treatment; 2) Double annealing: hang vertically to ensure that the strength meets σb=980~1180MPa; 3) Fitter: Straighten the product to ensure that the straightness is within the specified range; 4) Stress relief annealing: eliminate residual stress of products; 5) Turning: First drill the center hole; then turn the clamping process section; then use a special spherical clamping sleeve to clamp the process section, one clamp and one top turn the outer circle, leaving a double-sided margin of 1.7mm; 6) Centerless grinding: grinding the outer circle, leaving a double-sided allowance of 1.4mm; 7) Stress relief annealing: eliminate residual stress of products; 8) Number turning: remove the original center hole, and then re-drill the center hole at both ends of the product; 9) Turning: Use a pin to push the center holes at both ends, turn the outer circle, and leave a double-sided margin of 0.2mm; 10) Centerless grinding: grinding the outer circle to the required size of the product; 11) General lathe: Use polishing cotton to polish the sharp corners of the groove to ensure smooth transition; 12) Counting and turning: turning the diameter of the thread rolling blank and the diameter of the square blank; 13) Milling: Milling wrench and twisting square; 14) Deburring: remove burrs on all sides; 15) Thread rolling: rolling threads at both ends; 16) Fluorescent flaw detection; 17) Anodizing; 18) Counting and lathing: remove the anodized layer on both ends to ensure the overall length is qualified; 19) Label preparation: Electrolysis method is used for label preparation; 20) General inspection; 21) Storage.

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