Laser welding method for engine case part mounting seat and laser welding front air protection device

Abstract

The application discloses a laser welding method for an aero-engine casing part mounting seat and a laser welding front face ventilation protection device. The device comprises a first support, an L-shaped support, a cavity, an outer cover and a rubber pad. One end of the first support is connected with a laser, the L-shaped support is connected with the first support through bolts, the outer cover is slidably sleeved outside the cavity, the outer surface of the cavity is connected with the second end of the L-shaped support, a channel for a laser beam is formed on the cavity, an argon inlet is arranged on the upper end surface of the cavity, an argon outlet is arranged on the lower end surface of the cavity, the lower end surface of the outer cover is open, and the rubber pad is arranged between the circumferential surface of the annular protrusion and the inner wall of the outer cover. Before laser welding is performed by using the device, only the device needs to be removed to program a track, the programming difficulty is low, the welding seam is blown and protected for a longer time during welding, the argon concentration is higher, and the internal quality and appearance quality of the welding seam can be obviously improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of laser welding, and particularly relates to a laser welding front ventilation protection device for an annular welding seam of a mounting seat of an aero-engine casing part and a welding method. BACKGROUND

[0002] Mounting seat welding is a common machining process in the field of aero-engine manufacturing, especially for casing parts. The mounting seat and the casing shell are usually welded by fusion welding (argon arc welding, vacuum electron beam welding, laser welding, etc.), and compared with other welding methods, laser welding has the characteristics of small heat input and low welding environment requirement, and has certain advantages for casing mounting seat welding. However, there are two problems in the laser welding of the casing mounting seat:

[0003] 1) The laser welding speed is fast, and when the coaxial or side-shaft protection gas is used to protect the front of the welding seam, the blowing protection time for the welding seam area is short, and the blowing is usually completed before the welding seam cools down, resulting in serious oxidation of the welding seam and poor welding quality;

[0004] 2) For the laser welding equipment using side-shaft protection gas, the angle of the manipulator needs to be adjusted in real time when the annular welding track of the mounting seat is programmed, so as to prevent the interference between the side-shaft protection device and the mounting seat, and therefore the programming difficulty of the welding track is high and the programming efficiency is low.

[0005] The existence of the above two problems seriously affects the application of laser welding in the field of aero-engine manufacturing, and therefore, a suitable laser welding front seam protection scheme for the casing mounting seat is urgently needed. SUMMARY

[0006] The application aims to provide a laser welding method for a casing part mounting seat of an aero-engine and a laser welding front ventilation protection device, which can realize the inert atmosphere protection of the front welding seam of the mounting seat with different heights, prevent the oxidation of the welding seam, improve the welding quality, and also reduce the programming difficulty of the welding track of the mounting seat and improve the laser welding processing efficiency.

[0007] In order to achieve the above purpose, the application adopts the following technical scheme:

[0008] The laser welding front ventilation protection device for the casing part mounting seat of the aero-engine comprises,

[0009] A first support, one end of the first support is connected with a laser, a circular adjusting hole and a bolt hole are opened in the first support, and the circular adjusting hole intersects with the bolt hole;

[0010] An L-shaped support, a first end of the L-shaped support passes through the circular adjusting hole of the first support and is connected with the first support through a bolt placed in the bolt hole;

[0011] The cavity and the cover are sleeved outside the cavity, the outer surface of the cavity is connected with the second end of the L-shaped support, a channel for laser beam is opened on the cavity, the channel penetrates the upper end surface and the lower end surface of the cavity along the axis of the cavity, an argon gas flow cavity is formed between the channel and the inner wall of the cavity, a circular outward annular protrusion is arranged near the lower end surface of the cavity, the upper end surface of the cavity is provided with an argon gas inlet, the lower end surface of the cavity is provided with an argon gas outlet, the upper end surface of the cover is provided with an opening with an inner diameter between the minimum outer diameter of the cavity and the maximum outer diameter of the annular protrusion, and the lower end surface of the cover is open.

[0012] The rubber pad is arranged between the circumferential surface of the annular protrusion and the inner wall of the cover.

[0013] Further, the argon gas flow cavity of the cavity is provided with a flow regulator, and the flow regulator is arranged between the argon gas inlet and the argon gas outlet.

[0014] Further, the flow regulator is a plate with a cross section consistent with the cross section of the argon gas flow cavity, and a plurality of through holes are opened on the plate, and the direction of the through holes is parallel to the channel on the cavity.

[0015] Further, the argon gas outlet is a plurality of through holes opened in the lower end surface of the cavity, and the through holes are in communication with the argon gas flow cavity.

[0016] Further, the cavity is cylindrical, the cover is cylindrical, and the inner diameter of the cover is greater than the sum of the radius of the mounting seat and the radius of the welding seam.

[0017] The laser welding method of the mounting seat of the aero-engine casing part adopts the laser welding front air protection device, and comprises the following steps:

[0018] Step one, welding track programming, the welding track programming of the mounting seat is completed by using the laser welding machine teaching device in the visible state of the welding seam of the mounting seat;

[0019] Step two, welding, the first end of the first support is connected with the laser, the bolt is loosened, the first end of the L-shaped support is inserted into the circular adjusting hole of the first support, the L-shaped support is rotated and moved up and down until the cover covers the entire mounting seat and the channel for the laser beam is located directly above the welding seam, at this time, the bolt is tightened, the position of the cover on the cavity is adjusted up and down, and then the laser welding is started.

[0020] The laser welding method of the mounting seat of the aero-engine casing part adopts the laser welding front air protection device, and comprises the following steps:

[0021] Step one, install and adjust the position of the laser welding front air protection device, connect the first end of the first support with the laser, loosen the bolt, insert the first end of the L-shaped support into the circular adjustment hole of the first support, rotate the L-shaped support with the circular adjustment hole axis of the first support as the pivot after lifting the L-shaped support upward, until the weld is completely visible, at which time the bolt is tightened;

[0022] Step two, weld trajectory programming, complete the mounting seat weld trajectory programming using the laser welding machine test instructor;

[0023] Step three, welding, loosen the bolt, rotate and move the L-shaped support up and down until the cover covers the entire mounting seat while the channel for the laser beam is located directly above the weld, at which time the bolt is tightened, slide the position of the cover up and down on the cavity, and then start the laser welding.

[0024] Compared with the prior art, the laser welding front air protection device and the laser welding method provided by the application have the following characteristics:

[0025] (1) When the laser welding front air protection device is used to protect the laser welding of the machine case mounting seat, the time for blowing air protection to the weld is longer, the argon concentration is higher, and the internal quality and appearance quality of the weld can be significantly improved.

[0026] (2) The height of the cover of the laser welding front air protection device is adjustable, and is suitable for welding of mounting seats of different heights.

[0027] (3) After using the laser welding front air protection device, when programming the welding trajectory, the angular position of the laser does not need to be adjusted, the programming difficulty is low, and the processing efficiency is high. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is the schematic diagram of the laser welding front air protection device of the application;

[0029] Figure 2 is the welding schematic diagram using the laser welding front air protection device of the application;

[0030] Figure 3 is the perspective view of the main structure of the laser welding front air protection device;

[0031] In the figure, 1 is the first support, 2 is the L-shaped support, 3 is the cavity, 4 is the pipe, 5 is the rectifier, 6 is the argon inlet, 7 is the argon outlet, 8 is the cover, 9 is the rubber pad, 10 is the laser, 11 is the laser beam, 12 is the mounting seat, 13 is the machine case shell, 14 is the weld, 15 is the argon flow, and 16 is the bolt. DETAILED DESCRIPTION

[0032] The application will be further described in conjunction with the accompanying drawings and specific embodiments, but should not be understood as the scope of the subject matter described herein is limited to the following embodiments, any modifications, substitutions and changes made according to the ordinary technical knowledge and common practice in the art without departing from the above technical idea of the application are included in the scope of the application.

[0033] As shown in Figures 1-3 , the application designs and manufactures a laser welding front face ventilation protection device for a machine case type part mounting seat.

[0034] As shown in Figure 1 , the laser welding front face ventilation protection device mainly consists of a cavity 3, an outer cover 8, a rectifier 5, a rubber pad 9, a pipe 4, a first support 1, an L-shaped support 2, a bolt 16 and the like. The cavity 3 and the outer cover 8 are a piston type connection structure, wherein the cavity 3 has a ring-shaped protrusion on the outer side of the lower end as a sliding limiting structure placed inside the outer cover 8, the cavity 3 has a through hole in the center as a channel for the laser beam 11, the upper end surface of the cavity 3 is connected with a pipe 4 as an argon gas inlet 6, and the lower end surface of the cavity 3 is provided with dense small holes as an argon gas outlet 7. A porous rectifier 5 is installed inside the cavity 3, which plays a role of rectifying argon gas (uniform argon gas flow 15 is formed in the rectifier 5), so that the argon gas flow distribution is more uniform. Figure 1 The outer cover 8 is a circular ring cover, and the radius of the outer cover 8 is slightly larger than the sum of the radius of the weld 14 (R1 in Figure 2 ) and the radius of the boss of the mounting seat 12 (R2 in Figure 2 ), which can ensure that the protection device will not collide with the mounting seat 12 during the entire welding process.

[0035] As shown in Figure 1 , a ring-shaped rubber pad 9 is also installed between the outer cover 8 and the ring-shaped protrusion of the cavity 3, which can realize the fixation of the outer cover 8 and the cavity 3, and can make the outer cover 8 have a damping up and down sliding, so as to adjust the height of the outer cover 8 according to the height of the mounting seat 12; on the other hand, it can realize sealing and improve the argon gas protection effect. An L-shaped support 2 is connected to the outer side surface of the cavity 3, one end of the L-shaped support 2 is inserted into the circular adjusting hole of the first support 1, and the L-shaped support 2 and the first support 1 are fixedly connected through the bolt 16. When the bolt 16 is loosened, the rotation and up and down movement of the L-shaped support 2 in the circular adjusting hole can be realized, and the first support 1 is used to connect the laser 10 to realize the fixation of the entire protection device.

[0036] When laser welding is performed, as shown in Figure 2The first support 1 is used to connect the protection device to the laser 10, and the laser beam 11 can pass through the through hole of the protection device to reach the weld 14 and perform welding. When programming the welding track, the cover 8 can be pushed up, and the L-shaped support 2 is rotated to move the protection device away, so that the weld 14 is visible. After the welding track is programmed, the L-shaped support 2 is rotated, the cover 8 is moved down to the appropriate position, and welding is completed.

[0037] The laser welding method using the laser welding front air protection device of the aero-engine case part mounting seat is as shown in the figure, and the steps are as follows: Figure 2

[0038] ①The first support 1 is fixed on the laser 10, and the L-shaped support 2 can be selected not to be installed or rotated to the appropriate position to ensure that the weld 14 is visible, Figure 2 The weld 14 is a circular weld around the mounting seat 12;

[0039] ②The mounting seat 12 welding track programming is completed by using the laser welding machine teaching device;

[0040] ③The L-shaped support 2 is installed, the angular position of the L-shaped support 2 is adjusted, and the height of the cover 8 is adjusted to ensure that the cover 8 can cover the mounting seat 12 without interference. The vertical distance between the open end of the cover 8 and the weld can be set to 1-2mm, which can avoid the contact between the lower end of the cover 8 and the welded part, and also avoid the air entering the protection area of the cover 8, affecting the protection effect;

[0041] ④The laser welding machine is operated, and the protection device moves along with the welding machine along the welding track until the welding is completed.

[0042] When the mounting seat is laser welded by using the traditional coaxial or paraxial protection device, the air blowing device only has a protection effect on the laser beam area (the air blowing protection area is small). In the process of moving the laser beam along the mounting seat ring weld, the air blowing protection position also moves quickly with the laser beam, so the protection time is short. The protection device of the present application uses the cover 8 to increase the protection area. After the laser beam passes through a region, the region is still within the air blowing range of the cover 8 for a period of time, so the air blowing protection time for the weld is longer. At the same time, since the cover 8 covers the weld area, the argon concentration is higher. Because argon is used for protection, air is not easy to enter the protection area, so the argon concentration is higher. When the coaxial or paraxial blowing protection is used, the weld is exposed to air, and the argon concentration in the weld area is relatively low.

[0043] ​The description of the application herein is not intended to be detailed and is well known to those skilled in the art. Although the above describes the specific embodiments of the application in order to facilitate the understanding of the application for those skilled in the art, it should be clear that the application is not limited to the scope of the specific embodiments, and for those skilled in the art, it is obvious that various changes are within the spirit and scope of the application defined and determined by the appended claims, and all the applications using the concept of the application are within the scope of protection.

Claims

1. The laser welding method of an aero-engine casing part mounting seat, the mounting seat weld is a circular ring, characterized in that: the laser welding front air protection device used includes: a first support (1), one end of the first support (1) is connected with a laser (10), a circular adjusting hole and a bolt hole are opened on the first support (1), and the circular adjusting hole intersects with the bolt hole; an L-shaped support (2), the first end of the L-shaped support (2) passes through the circular adjusting hole of the first support (1) and is connected with the first support (1) by a bolt (16) placed in the bolt hole; a cavity (3) and an outer cover (8), the outer cover (8) is slidably sleeved outside the cavity (3), the outer surface of the cavity (3) is connected with the second end of the L-shaped support (2), a channel for a laser beam (11) is opened on the cavity (3), the channel penetrates through the upper end face and the lower end face of the cavity (3) along the axis of the cavity (3), an argon gas flow cavity is formed between the channel and the inner wall of the cavity (3), there is a ring-shaped protrusion outward near the lower end face of the cavity (3), the upper end face of the cavity (1) is provided with an argon gas inlet (6), the lower end face of the cavity (1) is provided with an argon gas outlet (7), the upper end face of the outer cover (8) is provided with an opening with an inner diameter between the minimum outer diameter of the cavity (1) and the maximum outer diameter of the ring-shaped protrusion, the lower end face of the outer cover (8) is open, the outer cover (8) is a circular ring cover, the inner diameter of the outer cover (8) is greater than the sum of the radius of the weld (14) and the radius of the boss of the mounting seat (12); a rubber pad (9) is placed between the circumferential surface of the ring-shaped protrusion and the inner wall of the outer cover (8); the laser welding method includes the following steps: Step one, welding track programming, the mounting seat welding track programming is completed by using a laser welding machine trial instructor in a visible state of the mounting seat weld; Step two, welding, the first end of the first support (1) is connected with the laser (10), the bolt (16) is loosened, the first end of the L-shaped support (2) is inserted into the circular adjusting hole of the first support (1), the L-shaped support (2) is rotated and moved up and down until the outer cover (8) covers the entire mounting seat (12) while the channel for the laser beam (11) is located directly above the weld (14), at this time the bolt (16) is tightened, the position of the outer cover (8) is adjusted by sliding up and down on the cavity (3), and then laser welding is started; or, the laser welding method includes the following steps: Step one, installing and adjusting the position of the laser welding front air protection device, the first end of the first support (1) is connected with the laser (10), the bolt (16) is loosened, the first end of the L-shaped support (2) is inserted into the circular adjusting hole of the first support (1), the L-shaped support (2) is rotated about the circular adjusting hole axis of the first support (1) after being lifted upward, until the weld (14) is completely visible, at this time the bolt (16) is tightened; Step two, welding track programming, the mounting seat welding track programming is completed by using a laser welding machine trial instructor; ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Step three, welding, loosen the bolt (16), rotate, up and down the L-shaped bracket (2) until the cover (8) covers the entire mounting seat (12) while the channel for the laser beam (11) is located directly above the weld (14), at this time tighten the bolt (16), slide up and down the cavity (3) to adjust the position of the cover (8), and then start laser welding.

2. The method of claim 1, wherein: The argon flow cavity of the cavity (3) is provided with a rectifier (5) between the argon inlet (6) and the argon outlet (7).

3. The method of claim 2, wherein: The rectifier (5) is a plate with a cross section consistent with that of the argon flow cavity, and a plurality of through holes are formed in the plate, and the direction of the through holes is parallel to the channel on the cavity (3).

4. The method of claim 1, wherein: The argon outlet (7) is a plurality of through holes formed in the lower end surface of the cavity (3) and in communication with the argon flow cavity.

5. The method of claim 1, wherein: The cavity (3) is cylindrical.

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