CN113427108B

CN113427108B - Preparation and welding method for groove of barrel at inlet and outlet of corner section of large-scale low-temperature wind tunnel

Info

Publication number: CN113427108B
Application number: CN202110707622.8A
Authority: CN
Inventors: 闵晓峰; 吴梦先; 潘伍覃; 侯华东; 郭则明; 蒋杰; 黄攀宇
Original assignee: Wuhan Yiye Steel Structure Co Ltd
Current assignee: Wuhan Yiye Steel Structure Co Ltd
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2022-08-05
Anticipated expiration: 2041-06-24
Also published as: CN113427108A

Abstract

The application provides a method for preparing and welding a groove of a barrel body at an inlet and an outlet of a corner section of a large-scale low-temperature wind tunnel, which comprises the following steps: (1) dividing the inlet and outlet cylinder elliptical surface into 26 areas for scribing; (2) designing 26 areas of the inlet and outlet cylinder into 14 different groove forms; (3) preparing a groove on a tool platform by adopting plasma cutting; (4) and welding the inlet and outlet cylinder and the elliptical ring closure circular seam by adopting different welding methods, back chipping modes and welding sequences. The method can be used for preparing and welding the groove of the large corner section inlet and outlet cylinder body for the large low-temperature wind tunnel, and has the characteristics of simple method, high construction efficiency, low construction cost, easiness in operation, good welding quality and the like.

Description

Preparation and welding method for groove of barrel at inlet and outlet of corner section of large-scale low-temperature wind tunnel

Technical Field

The application relates to the field of wind tunnels, in particular to a method for preparing and welding grooves of barrel bodies at inlet and outlet of corner sections of a large-scale low-temperature wind tunnel.

Background

Since the advent of wind tunnels, significant progress has been made in aerodynamic research and aircraft development using wind tunnel technology, and its effects have become more and more significant. However, as the test object (such as an aircraft) becomes larger, the conventional windThe tunnel test faces some serious challenges, the most important of which is that the conventional wind tunnel can not be tested in the full-size Reynolds number, the high Reynolds number wind tunnel test is the premise and guarantee for realizing the fine aerodynamic design and accurate flight performance prediction of the aircraft, and the low-temperature wind tunnel is born and developed for solving the problem. The low-temperature wind tunnels are all designed with corner sections, each corner section consists of an outlet cylinder, an inlet cylinder and an elliptical ring, the contact surface of the inlet cylinder and the outlet cylinder and the elliptical ring is an elliptical surface which is generally obtained by 45-degree beveling, and the thickness of the elliptical surface is determined from the thickness of the elliptical surface

Continuously change, wherein t ₀ Is the thickness of the inlet and outlet cylinder. The elliptical surface is an end surface with variable thickness, so that great difficulty is brought to groove preparation and welding, and the existing manufacturing processes comprise the following two steps:

firstly, the inlet and outlet cylinder body is directly closed up with the elliptical ring, the inner side closure part is planed to form a groove by adopting a carbon arc gouging, the inner side is welded, then the outer side closure part is planed to form a groove by continuously adopting the carbon arc gouging, and the outer side is welded. The process is simple and easy to implement, and is suitable for small-sized carbon steel wind tunnels, large-sized low-temperature wind tunnels are made of austenitic stainless steel, heat input brought by carbon arc gouging can cause great welding deformation, and simultaneously, the elliptical surfaces of the large-sized low-temperature wind tunnels are large, so that the carbon arc gouging is low in efficiency, high in strength and poor in working environment.

And secondly, processing the inlet and outlet cylinder elliptical surfaces into standard 45-degree oblique cutting elliptical surfaces by adopting a large planer type milling machine, processing K-shaped or single V-shaped grooves on the elliptical ring end surfaces, and performing folding welding. The process can effectively ensure the consistency of the bevel angle, the bevel processing quality is high, but the one-time investment cost is high, the larger the size of the inlet and outlet cylinder is, the higher the processing cost is, and the trend of large-scale development of the low-temperature wind tunnel is difficult to meet.

Disclosure of Invention

One of the purposes of the application is to provide a method for preparing and welding bevels of inlet and outlet cylinder bodies of a large-scale low-temperature wind tunnel corner section, and the method aims at solving the problem that the bevels of the inlet and outlet cylinder bodies of the existing wind tunnel corner section are difficult to machine.

The technical scheme of the application is as follows:

a preparation and welding method for a groove of a barrel body at an inlet and an outlet of a corner section of a large-scale low-temperature wind tunnel comprises the following steps:

step S1, drawing lines on the elliptical surfaces of the inlet and outlet cylinder in regions: along the direction of low-temperature wind tunnel airflow, the lowest point of an elliptical surface of the inlet and outlet cylinder is set as an axis of 0 degree, the highest point is set as an axis of 180 degrees, the short side is set as an axis of 90 degrees, and the long side is set as an axis of 270 degrees, and the cylinder wall of the inlet and outlet cylinder is marked; the angle formed between the inlet and outlet cylinder wall and the elliptical ring end face along the direction from 0-degree axis to 270-degree axis is changed from 90-45-90 degrees, the elliptical surface of the inlet and outlet cylinder is divided into twenty-six areas, the 0-degree axis is taken as the starting line of the boundary of the twenty-six areas, and the angles theta formed between the inlet and outlet cylinder wall and the elliptical ring end face at the boundary of the twenty-six areas are 90 degrees, 79-81 degrees, 65-67 degrees, 58-60 degrees, 54-56 degrees, 50-52 degrees, 47-49 degrees, 50-52 degrees, 54-56 degrees, 58-60 degrees, 65-67 degrees, 79-81 degrees, 90 degrees, 79-81 degrees, 65-67 degrees, 58-60 degrees, 54-56 degrees, 50-52 degrees, 47-49 degrees, 47-52 degrees, 54-56 degrees, 58-60 degrees, 65-67 degrees and 79-81 degrees, and marking boundary lines of the twenty-six areas on the cylinder wall of the inlet and outlet cylinder;

step S2, performing regional groove design on the inlet and outlet cylinder: the end face of the elliptical ring is not beveled, and the elliptical surface of the inlet and outlet cylinder is designed into a K-shaped bevel;

step S3, groove preparation is carried out on the inlet and outlet cylinder body: an elliptical ring plate is arranged on a horizontal plane, the size of the center line of the elliptical ring plate is the same as that of the elliptical surface of the inlet and outlet cylinder, and the width of the elliptical ring plate is 600-900 mm; arranging 3-5 temporary piers on the elliptical ring plate, and placing the inlet and outlet cylinder on the temporary piers, wherein the elliptical surface of the inlet and outlet cylinder is parallel to the plane of the elliptical ring plate; cutting lines are respectively drawn on the outer wall surfaces and the inner wall surfaces of the twenty-six areas of the inlet and outlet cylinder body according to the designed groove form of the inlet and outlet cylinder body; placing a semi-automatic cutting trolley on the elliptical ring plate, erecting a plasma cutting torch, adjusting the cutting torch angle of the plasma cutting torch to the designed groove angle of the inlet and outlet cylinder, adjusting the cutting torch height of the plasma cutting torch and aligning the cutting torch on the cylinder wall of the inlet and outlet cylinder to cut a groove;

and step S4, welding the inlet and outlet cylinder with the elliptical ring.

As one technical solution of the present application, in step S1, the angles θ between the entrance and exit cylinder walls and the elliptical ring end faces at the boundaries of the twenty-six regions are 90 °, 80 °, 66 °, 60, 55 °, 51 °, 47 °, 51 °, 55 °, 60 °, 66 °, 80 °, 90 °, 80 °, 66 °, 60 °, 55 °, 51 °, 47 °, 51 °, 55 °, 60 °, 66 °, and 80 °.

As one technical solution of the present application, in step S2, the groove form and angle of the axial region of 0 ° to 90 ° to 180 ° of the inlet/outlet cylinder are:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder and the end face of the elliptical ring changes from 90 degrees to 79 degrees to 81 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface of the inlet and outlet cylinder is 40-45 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 35-40 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 79-81 degrees to 65-67 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 32-37 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 65-67 degrees to 58-60 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 30-35 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in the range of 58-60 degrees to 54-56 degrees, the groove angle theta 1 of the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 of the outer arc side of the elliptical surface is 25-30 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in an area from 54 degrees to 56 degrees to 50 degrees to 52 degrees, the groove angle theta 1 of the inner arc side of the elliptical surface is 40 degrees to 45 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 of the outer arc side of the elliptical surface is 20 degrees to 23 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 50-52 degrees to 47-49 degrees, the groove angle theta 1 of the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 of the outer arc side of the elliptical surface is 17-20 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 47-49 degrees to 47-49 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 14-17 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface.

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 90 degrees to 80 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 35 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 80 degrees to 66 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 35 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 66 degrees to 60 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 32 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 60 degrees to 55 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 25 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 55 degrees to 51 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 23 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 51 degrees to 47 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 18 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in the region of 47-47 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, and the groove angle theta 2 on the outer arc side of the elliptical surface is 15 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface.

As one technical solution of the present application, in step S2, the groove form and angle of the 180 ° to 270 ° to 0 ° axial region of the inlet/outlet cylinder are:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 90 degrees to 79 degrees to 81 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 35-40 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 79-81 degrees to 65-67 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 32-37 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 65-67 degrees to 58-60 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 30-35 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in the range of 58-60 degrees to 54-56 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 25-30 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in an area from 54 degrees to 56 degrees to 50 degrees to 52 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40 degrees to 45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 20 degrees to 23 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 50-52 degrees to 47-49 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 17-20 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 47-49 degrees to 47-49 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 14-17 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface.

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 90 degrees to 80 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 35 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 80 degrees to 66 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 35 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 66 degrees to 60 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 32 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 60 degrees to 55 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 25 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 55 degrees to 51 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 23 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 51 degrees to 47 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 18 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in the region of 47-47 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, and the groove angle theta 2 on the inner arc side of the elliptical surface is 15 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface.

As one technical solution of the present application, in step S3, the width of the elliptical ring plate is 800 mm.

As an embodiment of the present invention, in step S4, the inlet/outlet cylinder and the elliptical ring are welded in the following manner:

when the angle theta formed between the inlet and outlet cylinder wall and the end face of the elliptical ring is in an area of 90-58-60 degrees, backing welding is carried out on the welding position of the inlet and outlet cylinder wall and the elliptical ring by argon arc welding, filling cover surface welding is carried out on the welding position of the inlet and outlet cylinder wall and the elliptical ring by shielded metal arc welding, and welding is alternately carried out on the outer side and the inner side of the groove of the elliptical surface in the welding process until the welding is finished;

when the angle theta formed between the inlet and outlet cylinder wall and the elliptical ring end surface is in an area of 58-60 degrees to 54-56 degrees: backing welding is carried out on the area, located on the 0-90-180-degree axis of the inlet and outlet cylinder, through argon arc welding, 2-3 layers of welding are carried out on the outer side of the groove of the elliptical surface through argon arc welding until the width of the groove on the outer side of the elliptical surface is increased, and then welding rods are used for arc welding on the inner side and the outer side of the groove of the elliptical surface alternately until welding is finished; backing welding is carried out on the area, located on the 180-270-0-degree axis of the inlet and outlet cylinder, of the inlet and outlet cylinder by argon arc welding, 2-3 layers of argon arc welding are welded on the inner side of the groove of the elliptical surface until the width of the inner side groove of the elliptical surface is increased, and then welding rods are used for arc welding on the outer side and the inner side of the groove of the elliptical surface alternately until welding is finished;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring is in the range of 54-56-45 degrees: welding two layers on the inner side of the groove of the elliptical surface by adopting welding rod arc welding in the area of the 0-90-180-degree axis of the inlet and outlet cylinder, then performing back gouging on the outer side of the groove of the elliptical surface by adopting carbon arc gouging and polishing the back gouging part completely, and then alternately performing welding on the outer side and the inner side of the groove of the elliptical surface by adopting welding rod arc welding until the welding is finished; and welding two layers outside the groove of the elliptical surface by welding rod arc welding in the area of the 180-270-0-degree axis of the inlet and outlet cylinder, then performing back gouging on the inner side of the groove of the elliptical surface by carbon arc gouging and polishing the back gouging part, and then performing alternate welding on the inner side and the inner side of the groove of the elliptical surface by welding rod arc welding until the welding is finished.

The beneficial effect of this application:

the preparation and welding method for the groove of the barrel at the entrance and the exit of the corner section of the large-scale low-temperature wind tunnel has the characteristics of simple method, high construction efficiency, low construction cost, easiness in operation, good welding quality and the like, and has the following characteristics compared with the existing method:

(1) the method divides the inlet and outlet cylinder elliptical surface into 26 areas and prepares the cylinder elliptical surface in 14 groove forms, thereby simplifying the problem that the groove angle preparation is continuously changed due to the continuous change of the angles between the inlet and outlet cylinder wall and the elliptical ring end surface, and having strong practicability;

(2) the method adopts plasma cutting to prepare the groove according to the designed groove form, has the characteristics of simple method, high construction efficiency, low construction cost, easy operation and the like, and solves the problems of large welding deformation, low efficiency, high strength and poor operation environment of the groove prepared by adopting a carbon arc air gouging machine or the problems of high construction cost and difficulty in meeting the machining requirement of the large-scale low-temperature wind tunnel inlet and outlet cylinder by adopting a large-scale planer type milling machine to machine the groove;

(3) according to the method, different welding method combinations, different welding sequences and different back gouging modes are adopted according to the groove forms of different areas of the inlet and outlet cylinder, the problems of large welding deformation, wide back gouging range and more welding defects in the conventional process are solved, and the welding quality is effectively ensured.

Drawings

In order to more clearly explain the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that for those skilled in the art, other related drawings can be obtained from these drawings without inventive effort.

FIG. 1 is a schematic view of the inlet and outlet cylinder and the elliptical ring being closed together according to an embodiment of the present disclosure;

FIG. 2 is a schematic illustration of an inlet and outlet cylinder ellipsoidal partition provided in an embodiment of the present application;

FIG. 3 is a schematic diagram of a closure groove of the inlet and outlet cylinder and the elliptical ring provided in the embodiment of the present application;

fig. 4 is a schematic view of preparation of a groove of an inlet and outlet cylinder provided in an embodiment of the present application.

Icon: 1-inlet and outlet cylinder; 2-an elliptical ring; 3-an elliptical ring plate; 4-temporary pier stud.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.

In the description of the present application, it should be noted that the terms "upper", "lower", and the like refer to orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the present invention are conventionally placed in use, and are used for convenience in describing the present application and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present application.

Further, in the present application, unless expressly stated or limited otherwise, the first feature may be directly contacting the second feature or may be directly contacting the second feature, or the first and second features may be contacted with each other through another feature therebetween, not directly contacting the second feature. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.

Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present application, it is also to be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

Example (b):

referring to fig. 1 and fig. 2 to 4, the present application provides a method for preparing and welding a groove of a large-scale low-temperature wind tunnel corner section inlet and outlet cylinder, comprising the following steps:

step S1, drawing lines on the elliptical surfaces of the entrance/exit cylinder 1 in regions: along the direction of low-temperature wind tunnel airflow, the lowest point of an ellipsoid of the inlet and outlet cylinder 1 is defined as an axis of 0 degree, the highest point is defined as an axis of 180 degrees, the short side is defined as an axis of 90 degrees, and the long side is defined as an axis of 270 degrees, and the cylinder wall of the inlet and outlet cylinder 1 is marked; meanwhile, along the direction from the axis of 0 degree to the axis of 270 degrees, the angle formed between the cylinder wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 changes from 90 degrees to 45 degrees to 90 degrees, the elliptical surface of the inlet and outlet cylinder 1 is divided into twenty-six regions, the axis of 0 degree is taken as the starting line of the boundary of the twenty-six regions, and the angles theta formed between the cylinder wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 at the boundary of the twenty-six regions are sequentially 90 degrees, 79-81 degrees, 65-67 degrees, 58-60 degrees, 54-56 degrees, 50-52 degrees, 47-49 degrees, 50-52 degrees, 54-56 degrees, 58-60 degrees, 65-67 degrees, 79-81 degrees, 90 degrees, 79-81 degrees, 65-67 degrees, 58-60 degrees, 54-56 degrees, 50-52 degrees, 47-49 degrees, 47-52 degrees, 54-56 degrees, 58-60 degrees, 65-67 degrees, 79-81 degrees, and marking the boundary lines of twenty-six areas on the cylinder wall of the inlet and outlet cylinder body 1;

step S2, performing regional groove design on the inlet and outlet cylinder 1, wherein the end face of the elliptical ring 2 is not provided with a groove, and the elliptical face of the inlet and outlet cylinder 1 is designed into a K-shaped groove:

further, the form and angle of the groove of the axial line region of 0 to 90 to 180 degrees of the inlet and outlet cylinder 1 are as follows:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 changes from 90 degrees to 79 degrees to 81 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface of the inlet and outlet cylinder 1 is 40 degrees to 45 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 35 degrees to 40 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 79-81 degrees to 65-67 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 32-37 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes in the range of 65-67 degrees to 58-60 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 30-35 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes in the range of 58-60 degrees to 54-56 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 25-30 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes in the region of 54-56 degrees to 50-52 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 20-23 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 50-52 degrees to 47-49 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 17-20 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 47-49 degrees to 47-49 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 14-17 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

further, the groove form and angle of the 180-270-0 degree axial line region of the inlet and outlet cylinder 1 are as follows:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 90 degrees to 79 degrees to 81 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 35-40 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 79-81 degrees to 65-67 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 32-37 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes in the range of 65-67 degrees to 58-60 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 30-35 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes in the range of 58-60 degrees to 54-56 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 25-30 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes in the region of 54-56 degrees to 50-52 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 20-23 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 50-52 degrees to 47-49 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 17-20 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end face of the elliptical ring 2 changes from 47-49 degrees to 47-49 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 14-17 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface;

step S3, groove preparation is performed on the inlet and outlet cylinder 1: an elliptical ring plate 3 is arranged on a horizontal plane, the central line of the elliptical ring plate 3 is the same as the elliptical surface of the inlet and outlet cylinder 1 in size, and the width is 600-900 mm; arranging 3-5 temporary piers 4 on the elliptical ring plate 3, and placing the inlet and outlet cylinder 1 on the temporary piers 4, wherein the elliptical surface of the inlet and outlet cylinder 1 is parallel to the plane of the elliptical ring plate 3; cutting lines are respectively drawn on the outer wall surfaces and the inner wall surfaces of twenty-six areas of the inlet and outlet cylinder 1 according to the groove form designed for the inlet and outlet cylinder 1; placing a semi-automatic cutting trolley on the elliptical ring plate 3, erecting a plasma cutting torch, adjusting the cutting torch angle of the plasma cutting torch to the designed groove angle of the inlet and outlet cylinder 1, adjusting the cutting torch height of the plasma cutting torch and aligning the cutting torch on the cylinder wall of the inlet and outlet cylinder 1 to cut a groove; in addition, in the cutting process, a cutting track line can be drawn on the elliptical ring plate 3, manual guiding trolley cutting can be carried out along the cutting track line, an elliptical track can also be manufactured, and a semi-automatic cutting trolley is placed on the elliptical track for automatic cutting;

step S4, welding the inlet/outlet cylinder 1 and the elliptical ring 2: before welding, the elliptical surface of the inlet and outlet cylinder 1 needs to be thoroughly polished to remove an oxide layer and impurities; the inlet and outlet cylinder 1 and the elliptical ring 2 can then be welded in the following manner:

when the angle theta formed between the wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 is in an area of 90-58-60 degrees, backing welding is carried out on the welding position of the wall of the inlet and outlet cylinder 1 and the elliptical ring 2 by argon arc welding, filling cover surface welding is carried out on the welding position of the wall of the inlet and outlet cylinder 1 and the elliptical ring 2 by shielded metal arc welding, and welding is alternately carried out on the outer side and the inner side of a groove of an elliptical surface in the welding process until the welding is finished;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 is in the area of 58-60 degrees to 54-56 degrees: backing welding is carried out on the area of the 0-90-180-degree axis of the inlet and outlet cylinder body 1 by adopting argon arc welding, 2-3 layers of argon arc welding are welded on the outer side of the groove of the elliptical surface until the width of the outer groove of the elliptical surface is increased, and then welding rods are adopted to carry out arc welding on the inner side and the outer side of the groove of the elliptical surface alternately until the welding is finished; backing welding is carried out on the area of the 180-270-0-degree axis of the inlet and outlet cylinder body 1 by argon arc welding, 2-3 layers of argon arc welding are welded on the inner side of the groove of the elliptical surface until the width of the inner side groove of the elliptical surface is increased, and welding rods are used for arc welding on the outer side and the inner side of the groove of the elliptical surface alternately until welding is finished;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 is in the range of 54-56-45 degrees: welding rods are adopted to perform arc welding on the inner side of the groove of the elliptical surface to weld two layers in the area of the 0-90-180-degree axis of the inlet and outlet cylinder body 1, then carbon arc gouging is adopted to perform back gouging on the outer side of the groove of the elliptical surface and polish the back gouging part completely, and then welding rods are adopted to perform arc welding on the outer side and the inner side of the groove of the elliptical surface alternately until the welding is completed; and welding the two layers outside the groove of the elliptical surface by welding rod arc welding in the area of the 180-270-0-degree axis of the inlet and outlet cylinder 1, then performing back gouging on the inner side of the groove of the elliptical surface by carbon arc gouging and polishing the back gouging part completely, and then performing alternate welding on the inner side and the inner side of the groove of the elliptical surface by welding rod arc welding until the welding is finished.

In this embodiment, the method can be applied to preparation and welding of the groove of the inlet and outlet cylinder body of the corner section of the large-scale low-temperature wind tunnel with the inlet and outlet cylinder body 1 having the elliptical surface with the minor axis length of 7500mm, the major axis length of 10585mm, the shell thickness of 50mm and the material of 304L.

Further, in this embodiment, in step S1, the angles θ between the cylindrical wall of the inlet/outlet cylinder 1 and the end face of the elliptical ring 2 at the boundaries of the twenty-six regions are 90 °, 80 °, 66 °, 60, 55 °, 51 °, 47 °, 51 °, 55 °, 60 °, 66 °, 80 °, 90 °, 80 °, 66 °, 60 °, 55 °, 51 °, 47 °, 51 °, 55 °, 60 °, 66 °, and 80 °, in this order.

Specifically, in this embodiment, in step S2, the groove forms and angles of the axial regions of 0 ° to 90 ° to 180 ° of the inlet/outlet cylinder 1 are:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in a region from 90 degrees to 80 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 35 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes from 80 degrees to 66 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 35 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in the range of 66 degrees to 60 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 32 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in the range of 60 degrees to 55 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 25 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes from 55 degrees to 51 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 23 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in the region of 51-47 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 18 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 changes in the region of 47-47 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees and the groove thickness is 3/5 of the elliptical surface thickness, and the groove angle theta 2 on the outer arc side of the elliptical surface is 15 degrees and the groove thickness is 2/5 of the elliptical surface thickness.

Specifically, in this embodiment, in step S2, the groove form and angle of the 180 ° to 270 ° to 0 ° axial region of the inlet/outlet cylinder 1 are:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in a region from 90 degrees to 80 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 1/2 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 35 degrees, and the groove thickness is 1/2 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes from 80 degrees to 66 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 35 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in the range of 66 degrees to 60 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 32 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in the range of 60 degrees to 55 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 25 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes from 55 degrees to 51 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 23 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 changes in the region of 51-47 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees, the groove thickness is 4/7 of the thickness of the elliptical surface, the groove angle theta 2 on the inner arc side of the elliptical surface is 18 degrees, and the groove thickness is 3/7 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 changes in the region of 47-47 degrees, the groove angle theta 1 on the outer arc side of the elliptical surface is 40 degrees and the groove thickness is 7/13 of the elliptical surface thickness, and the groove angle theta 2 on the inner arc side of the elliptical surface is 15 degrees and the groove thickness is 6/13 of the elliptical surface thickness.

Specifically, in the present embodiment, in step S3, the width of the elliptical ring plate 3 may be 800 mm.

Specifically, in the present embodiment, in step S4, the inlet/outlet cylinder 1 and the elliptical ring 2 may be welded in the following manner:

(1) when the angle theta formed between the wall of the inlet and outlet cylinder 1 and the end face of the elliptical ring 2 is in a 90-60-degree region, backing welding is carried out on the welding position of the wall of the inlet and outlet cylinder 1 and the elliptical ring 2 by argon arc welding, filling cover face welding is carried out on the welding position of the wall of the inlet and outlet cylinder 1 and the elliptical ring 2 by shielded metal arc welding, and welding is alternately carried out on the outer side and the inner side of a groove of the elliptical surface in the welding process until the welding is finished;

(2) when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 is in the range of 60-55 degrees: backing welding is carried out on the area, located on the axis of the barrel body at 0-90-180 degrees, by argon arc welding, 2-3 layers of welding are continuously carried out on the outer side of the groove by argon arc welding until the width of the groove on the outer side is increased, and then welding rods are adopted to carry out arc welding on the inner side and the outer side of the groove alternately until the welding is finished; backing welding is carried out on the area of the 180-270-0-degree axis of the cylinder body by adopting argon arc welding, 2-3 layers of argon arc welding are continuously adopted on the inner side of the groove until the width of the inner groove is increased, and then welding rods are adopted to carry out arc welding on the outer side and the inner side of the groove alternately until the welding is finished;

(3) when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body 1 and the end surface of the elliptical ring 2 is in the range of 55-45 degrees: welding two layers on the inner side of the groove by adopting welding rod arc welding in a region of 0-90-180 degrees of the axis of the cylinder body, then performing back gouging on the outer side of the groove by adopting carbon arc gouging, thoroughly polishing the back gouging part, and alternately welding the outer side and the inner side of the groove by adopting welding rod arc welding until the welding is finished; and welding two layers of the inlet and outlet barrel 1180-270-0 degree axial line regions on the outer side of the groove by adopting welding rod arc welding, then performing back gouging on the inner side of the groove by adopting carbon arc gouging, thoroughly polishing the back gouging part, and alternately welding the inner side and the inner side of the groove by adopting welding rod arc welding until the welding is completed.

In conclusion, the preparation and welding method for the groove of the barrel body at the entrance and the exit of the corner section of the large-scale low-temperature wind tunnel has the characteristics of simple method, high construction efficiency, low construction cost, easiness in operation, good welding quality and the like, and compared with the existing method, the preparation and welding method has the following characteristics:

(1) the method divides the elliptical surface of the inlet and outlet cylinder 1 into 26 regions to prepare 14 groove forms, simplifies the problem that the groove angle preparation is continuously changed due to the continuous change of the angles of the cylinder wall of the inlet and outlet cylinder 1 and the end surface of the elliptical ring 2, and has strong practicability;

(2) the method adopts plasma cutting to prepare the groove according to the designed groove form, has the characteristics of simple method, high construction efficiency, low construction cost, easy operation and the like, and solves the problems of large welding deformation, low efficiency, high strength and poor operation environment of the groove prepared by adopting a carbon arc air gouging machine or the problems of high construction cost and difficulty in meeting the processing requirement of the large low-temperature wind tunnel inlet and outlet cylinder body 1 by adopting a large planer type milling machine to process the groove;

(3) according to the method, different welding method combinations, different welding sequences and different back gouging modes are adopted according to the groove forms of different areas of the inlet and outlet cylinder body 1, the problems of large welding deformation, wide back gouging range and more welding defects in the conventional process are solved, and the welding quality is effectively ensured.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A preparation and welding method for a groove of a barrel body at an inlet and an outlet of a corner section of a large-scale low-temperature wind tunnel is characterized by comprising the following steps:

step S1, drawing lines on the elliptical surfaces of the inlet and outlet cylinder in regions: along the direction of low-temperature wind tunnel airflow, the lowest point of an elliptical surface of the inlet and outlet cylinder is set as an axis of 0 degree, the highest point is set as an axis of 180 degrees, the short side is set as an axis of 90 degrees, and the long side is set as an axis of 270 degrees, and the cylinder wall of the inlet and outlet cylinder is marked; the angle formed between the inlet and outlet cylinder wall and the end face of the elliptical ring along the direction from 0-degree axis to 270-degree axis is changed from 90-45-90 degrees, the elliptical surface of the inlet and outlet cylinder is divided into twenty-six areas, the 0-degree axis is taken as the starting line of the boundary of the twenty-six areas, and the angles theta formed between the inlet and outlet cylinder wall and the end face of the elliptical ring at the boundary of the twenty-six areas are 90 degrees, 79-81 degrees, 65-67 degrees, 58-60 degrees, 54-56 degrees, 50-52 degrees, 47-49 degrees, 50-52 degrees, 54-56 degrees, 58-60 degrees, 65-67 degrees, 79-81 degrees, 90 degrees, 79-81 degrees, 65-67 degrees, 58-60 degrees, 54-56 degrees, 47-52 degrees, 47-49 degrees, 50-52 degrees, 54-56 degrees, 58-60 degrees, 65-67 degrees and 79-81 degrees, and marking boundary lines of the twenty-six areas on the cylinder wall of the inlet and outlet cylinder;

step S2, performing regional groove design on the inlet and outlet cylinder: the end face of the elliptical ring is not beveled, and the elliptical surface of the inlet and outlet cylinder is designed into a K-shaped bevel; in step S2, the form and angle of the groove of the axial region of the inlet/outlet cylinder from 0 ° to 90 ° to 180 ° are:

when an angle theta formed between the cylindrical wall of the inlet and outlet cylinder and the end face of the elliptical ring changes from 54-56 degrees to 50-52 degrees, the groove angle theta 1 of the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 8/13 of the thickness of the elliptical surface, the groove angle theta 2 of the outer arc side of the elliptical surface is 20-23 degrees, and the groove thickness is 5/13 of the thickness of the elliptical surface;

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 47-49 degrees to 47-49 degrees, the groove angle theta 1 of the inner arc side of the elliptical surface is 40-45 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 of the outer arc side of the elliptical surface is 14-17 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface;

in step S2, the groove forms and angles of the 180 ° -270 ° -0 ° axial regions of the inlet and outlet cylinder are:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes from 47-49 degrees to 47-49 degrees, the groove angle theta 1 of the outer arc side of the elliptical surface is 40-45 degrees, the groove thickness is 7/13 of the thickness of the elliptical surface, the groove angle theta 2 of the inner arc side of the elliptical surface is 14-17 degrees, and the groove thickness is 6/13 of the thickness of the elliptical surface;

step S3, groove preparation is carried out on the inlet and outlet cylinder body: an elliptical ring plate is arranged on a horizontal plane, an elliptical surface formed by enclosing of the elliptical ring plate is the same as the elliptical surface of the inlet and outlet cylinder in size, and the width of the elliptical ring plate is 600-900 mm; arranging 3-5 temporary piers on the elliptical ring plate, and placing the inlet and outlet cylinder on the temporary piers, wherein the elliptical surface of the inlet and outlet cylinder is parallel to the plane of the elliptical ring plate; cutting lines are respectively drawn on the outer wall surfaces and the inner wall surfaces of the twenty-six areas of the inlet and outlet cylinder body according to the designed groove form of the inlet and outlet cylinder body; placing a semi-automatic cutting trolley on the elliptical ring plate, erecting a plasma cutting torch, adjusting the cutting torch angle of the plasma cutting torch to the designed groove angle of the inlet and outlet cylinder, adjusting the cutting torch height of the plasma cutting torch and aligning the cutting torch on the cylinder wall of the inlet and outlet cylinder to cut a groove;

and step S4, welding the inlet and outlet cylinder with the elliptical ring.

2. The preparation and welding method for the groove of the inlet and outlet cylinder of the large-scale low-temperature wind tunnel corner section according to claim 1, wherein in step S1, the angles θ between the cylinder wall of the inlet and outlet cylinder and the end face of the elliptical ring at the boundary of the twenty-six regions are 90 °, 80 °, 66 °, 60, 55 °, 51 °, 47 °, 51 °, 55 °, 60 °, 66 °, 80 °, 90 °, 80 °, 66 °, 60 °, 55 °, 51 °, 47 °, 51 °, 55 °, 60 °, 66 °, and 80 ° in sequence.

3. The method for preparing and welding the bevels of the inlet and outlet cylinder bodies of the corner sections of the large-scale low-temperature wind tunnel according to claim 1, wherein in step S2, the bevels of the axial line regions of the inlet and outlet cylinder bodies are in the forms and angles of 0-90-180 degrees:

when the angle theta formed between the cylinder wall of the inlet and outlet cylinder body and the end face of the elliptical ring changes in the region of 47-47 degrees, the groove angle theta 1 on the inner arc side of the elliptical surface is 40 degrees, the groove thickness is 3/5 of the thickness of the elliptical surface, the groove angle theta 2 on the outer arc side of the elliptical surface is 15 degrees, and the groove thickness is 2/5 of the thickness of the elliptical surface.

4. The method for preparing and welding the bevels of the inlet and outlet cylinder bodies of the corner sections of the large-scale low-temperature wind tunnel according to claim 1, wherein in step S2, the bevels of 180-270-0 ° axial regions of the inlet and outlet cylinder bodies are in the form and at the angle of:

5. The method for preparing and welding the groove of the inlet and outlet cylinder body of the corner section of the large-scale low-temperature wind tunnel according to claim 1, wherein in step S3, the width of the elliptical ring plate is 800 mm.

6. The method for preparing and welding the groove of the inlet and outlet cylinder body of the corner section of the large-scale low-temperature wind tunnel according to claim 1, wherein in step S4, the inlet and outlet cylinder body and the elliptical ring are welded in the following way:

when the angle theta formed between the inlet and outlet cylinder wall and the elliptical ring end surface is in an area of 58-60 degrees to 54-56 degrees: backing welding is carried out on the area, located in the 0-90-180-degree axis of the inlet and outlet cylinder, through argon arc welding, 2-3 layers of argon arc welding are welded on the outer side of the groove of the elliptical surface until the width of the outer groove of the elliptical surface is increased, and then welding rods are adopted to conduct arc welding on the inner side and the outer side of the groove of the elliptical surface alternately until welding is completed; backing welding is carried out on the area, located in the 180-270-0-degree axis of the inlet and outlet cylinder, through argon arc welding, 2-3 layers of argon arc welding are welded on the inner side of the groove of the elliptical surface until the width of the inner side groove of the elliptical surface is increased, and then welding rods are used for arc welding on the outer side and the inner side of the groove of the elliptical surface alternately until welding is finished;

when the angle theta formed between the inlet and outlet cylinder wall and the elliptical ring end surface is in the range of 54-56 degrees to 45 degrees: welding two layers on the inner side of the groove of the elliptical surface by welding rod arc welding in an area of 0-90-180 degrees of the inlet and outlet cylinder, then performing back gouging on the outer side of the groove of the elliptical surface by carbon arc gouging and polishing the back gouging part completely, and then performing alternate welding on the outer side and the inner side of the groove of the elliptical surface by welding rod arc welding until the welding is finished; welding two layers of welding rods on the outer side of the groove of the elliptical surface in an area located on the axis of the inlet and outlet cylinder body at an angle of 180-270 degrees to 0 degree through arc welding, then performing back gouging on the inner side of the groove of the elliptical surface through carbon arc gouging, polishing the back gouging part completely, and then performing alternate welding on the inner side and the inner side of the groove of the elliptical surface through arc welding of the welding rods until the welding is completed.