CN106583906B

CN106583906B - Method for improving quality of lap weld of inner cone mounting edge and cylinder

Info

Publication number: CN106583906B
Application number: CN201611068762.0A
Authority: CN
Inventors: 黄青松; 倪建成; 高献娟; 公维勇; 杨钊
Original assignee: Shenyang Liming Aero Engine Group Co Ltd
Current assignee: Shenyang Liming Aero Engine Group Co Ltd
Priority date: 2016-11-29
Filing date: 2016-11-29
Publication date: 2020-06-05
Anticipated expiration: 2036-11-29
Also published as: CN106583906A

Abstract

The invention discloses a method for improving the quality of lap weld of an inner cone mounting edge and a cylinder, which is characterized by comprising the following steps of: 1. changing the notch of the cylinder into a window, and processing the window of the cylinder by adopting a laser hole cutting process; 2. cleaning oil stains on the to-be-welded part of the mounting edge and the cylinder body and wiping the to-be-welded part; 3. assembling the matched mounting edge and the cylinder body together; 4. placing the part and the clamp on a positioner workbench of a vacuum electron beam welding machine for clamping; 5. closing the vacuum chamber of the electron beam welding machine and vacuumizing; 6. welding parts according to the adjusted qualified electron beam welding parameters; 7. the weld was examined by X-ray. The invention has the advantages that: the window structure and the mounting edge are in lap joint and are continuous, and the structure of an intermittent weld joint is improved into a whole-ring continuous weld joint, so that a fillet weld joint structure at the tail end of the weld joint is avoided, and stress concentration is reduced; the manual argon arc welding is improved into a vacuum electron beam scheme, and the back inert gas protection and the weld penetration rate of the weld are solved, so that the welding quality of parts is guaranteed, the repair welding times of the weld are reduced, the repair cost is reduced, and the safe service life of the inner cone is guaranteed.

Description

Method for improving quality of lap weld of inner cone mounting edge and cylinder

Technical Field

The invention relates to the technical field of manufacturing of aero-engines, in particular to a method for improving quality of lap welding seams of an inner cone mounting edge and a cylinder.

Background

After the inner cone (figure 1) is tested for 10 hours, visual or coloring inspection is carried out, the failure rate of the weld joint crack of the part is more than 50%, and the weld joint is 100% cracked after the part works for 300 hours and a life cycle, and repair welding is needed. The repair cost is increased, and the matching efficiency of batch production is influenced. The reason is analyzed, the installation edge 1 of the inner cone welding structure is in lap joint with the cylinder body 2, the wall of the cylinder body 2 is tightly attached to the installation edge 1, manual argon arc welding is used originally, the protection is not smooth due to argon gas flowing into the back, the actual argon arc welding penetration rate is only 10% -20%, the weld joint strength is extremely poor, and cracking faults are easily caused due to factors such as vibration and the like in the using process; the 15 notches form fillet weld structures at the ending parts of the argon arc welds, so that large stress concentration exists, initial crack edges of the welds are easily formed due to factors such as vibration in the using process, and potential safety hazards in use exist. Severely restricting the matching delivery of the product. In order to ensure that the production task of a factory is smoothly completed and reduce unnecessary quality loss of the factory by reducing the repair frequency of parts, the manufacturing quality of an inner cone needs to be improved, the process design needs to be carried out again, and the product percent of pass is improved.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a method for improving the quality of an overlap weld of an inner cone mounting edge and a cylinder, which comprises the following steps:

1. changing the notch of the cylinder into a window, and processing the window of the cylinder by adopting a laser hole cutting process;

2. cleaning oil stains on the to-be-welded part of the mounting edge and the cylinder body and wiping the to-be-welded part;

3. assembling the matched mounting edge and the cylinder body together, and tightly pressing the cylinder body and the mounting edge by adopting a clamp;

4. placing the part and the clamp on a positioner workbench of a vacuum electron beam welding machine for clamping;

5. closing the vacuum chamber of the electron beam welding machine and vacuumizing;

6. welding parts according to the adjusted qualified electron beam welding parameters;

7. the weld was examined by X-ray.

The invention has the advantages that: the window structure and the mounting edge are in lap joint and are continuous, and the structure of an intermittent weld joint is improved into a whole-ring continuous weld joint, so that a fillet weld joint structure at the tail end of the weld joint is avoided, and stress concentration is reduced; the manual argon arc welding is improved into a vacuum electron beam scheme, and the back inert gas protection and the weld penetration rate of the weld are solved, so that the welding quality of parts is guaranteed, the repair welding times of the weld are reduced, the repair cost is reduced, and the safe service life of the inner cone is guaranteed.

Drawings

FIG. 1 is a schematic view of an inner cone structure;

FIG. 2 is an enlarged view of an argon arc welding original structure of the inner cone mounting edge of FIG. 1 with a boss on the back surface in lap joint and butt joint;

FIG. 3 is a structure diagram of a fillet weld at the end of an argon arc weld before modification;

FIG. 4 is a structural view of an electron beam weld formed into a full circumferential weld after modification.

Detailed Description

The invention is described in detail below with reference to the accompanying drawings, fig. 1 is a schematic diagram of an inner cone structure, which is composed of a mounting edge 1 and a cylinder body 2.

The welding structure of the parts is originally welded by manual argon arc, because the installation edge 1 and the cylinder body 2 are in a lap joint structure, the wall of the cylinder body 2 is tightly attached to the installation edge 1, the actual argon arc welding penetration rate is only 10% -20% due to the fact that argon is not smoothly introduced to the back surface, the welding line strength is extremely poor, and cracking faults are easily generated due to factors such as vibration and the like in the using process; the 15 notches form fillet weld structures at the ending parts of the argon arc welds, so that large stress concentration exists, and initial crack edges of the welds are easily formed due to factors such as vibration and the like in the using process. The parts are always welded by manual argon arc welding, the welding quality is unstable, and after the test, visual inspection or coloring inspection shows that the failure rate of the welding seam cracks of the parts is only over 50 percent and repair welding is needed. After 300 hours of operation for a life cycle, nearly 100% crack failure. X-ray inspection shows that the parts are not welded through after welding.

FIG. 2 is an enlarged view of an original structure of argon arc welding in butt joint with a boss on the back surface of an inner cone mounting edge in FIG. 1, due to the overlapping structure of the mounting edge 1 and a cylinder 2, the wall of the cylinder 2 is tightly attached to the mounting edge, argon gas is not smoothly introduced to the position A on the back surface, the actual argon arc welding penetration rate is only 10% -20%, the weld joint strength is extremely poor, and cracking faults are easily caused due to factors such as vibration in the use process.

FIG. 3 is a structure diagram of fillet weld at the end of argon arc weld before improvement, because of the structure of the notch 3 at the lap 15 of the mounting edge 1 and the cylinder 2, the fillet weld structure is formed at the ending B of the argon arc weld, which has larger stress concentration and is easy to form the initial crack edge of the weld due to factors such as vibration and the like during use.

FIG. 4 is a structural diagram of an improved electron beam welding seam forming whole ring welding seam, a whole ring lap welding structure of the improved cylinder 2 is improved, an uninterrupted welding structure at the position C can adopt electron beam welding, and a whole ring welding seam structure D has no stress concentration, so that an original fillet welding seam stress concentration structure at the tail end of a welding seam is avoided; the argon arc welding is optimized to be a vacuum electron beam welding process, the problem of inert gas protection during welding is solved, electron beam welding directly penetrates through the back step structure E, the electron beam penetration rate is 100%, and the quality of a welding seam is reliable.

The method comprises the following specific operation steps:

1. optimizing the process structure, changing the 15-position notch of the cylinder body 2 into the 15-position window 3, and processing the cylinder body window 3 by adopting a laser hole cutting process as shown in figure 4;

2. cleaning oil stains on the to-be-welded part of the mounting edge 1 and the barrel 2 and wiping the to-be-welded part;

3. assembling the matched mounting edge 1 and the cylinder body 2 together, and tightly pressing the cylinder body and the mounting edge by adopting a simple clamp;

6. welding parts according to a debugging qualified electron beam welding parameter table 1;

7. the X-ray inspection welding line has no defects of incomplete penetration, incomplete fusion, cracks, shrinkage grooves and the like, and the welding line qualification rate is 100 percent.

TABLE 1 Electron Beam welding parameters

Claims

1. A method for improving the quality of lap weld of an inner cone mounting edge and a cylinder is characterized by comprising the following steps:

(1) The notch of the cylinder body is changed into a window, and the window structure is continuously lapped with the mounting edge, so that electron beam welding can be adopted; the structure of the intermittent weld joint is improved into a whole-ring continuous weld joint, so that the fillet weld joint structure at the tail end of the weld joint is avoided, and stress concentration is reduced; processing a cylinder window by adopting a laser hole cutting process;

(2) Cleaning oil stains on the to-be-welded part of the mounting edge and the barrel and wiping the to-be-welded part;

(3) Assembling the matched mounting edge and the cylinder body together, and tightly pressing the cylinder body and the mounting edge by adopting a clamp;

(4) Placing the part and the clamp on a positioner workbench of a vacuum electron beam welding machine for clamping;

(5) Closing the vacuum chamber of the electron beam welding machine and vacuumizing;

(6) Welding parts according to the adjusted qualified electron beam welding parameters;

electron beam welding parameters

(7) And X-ray inspection of the weld.