阅读说明：本技术 跨坐式单轨车构架底板预组件的制备方法 (Preparation method of straddle type monorail vehicle framework bottom plate pre-assembly ) 是由 纪益根 于馨智 于 2020-12-16 设计创作，主要内容包括：本发明公开了一种跨坐式单轨车构架底板预组件的制备方法,包括如下：(1)锻件加工；(2)将折弯板材和加工后的锻件通过压紧装置固定在焊接工装上,焊接工装带有焊接反变形设计,锻件和折弯板材与水平面之间均有5°的夹角；(3)焊接时将折弯板材和锻件之间的焊缝设为对接焊缝；每条对接焊缝采用先平焊位置焊接、后立焊位置焊接、再平焊位置焊接的方式完成,每条对接焊缝需连续完成焊接,焊接中不能停弧；(4)焊接完成并完全冷却后,取出所述底板预组件,检查焊缝即可,不需要焊后调型。采用本发明的对接接头的底板预组件产品对于焊缝强度、焊接质量、生产效率以及成本方面有积极促进作用。(The invention discloses a preparation method of a straddle type monorail vehicle framework bottom plate pre-assembly, which comprises the following steps: (1) processing a forged piece; (2) fixing the bent plate and the processed forged piece on a welding tool through a pressing device, wherein the welding tool is provided with a welding anti-deformation design, and the forged piece, the bent plate and a horizontal plane form an included angle of 5 degrees; (3) setting the welding seam between the bent plate and the forging as a butt welding seam during welding; each butt welding seam is finished by adopting a mode of firstly welding at a flat welding position, then welding at a vertical welding position and then welding at a flat welding position, each butt welding seam needs to be continuously finished, and arc stopping can not be carried out during welding; (4) and after welding is finished and the assembly is completely cooled, taking out the base plate pre-assembly, and checking a welding line without post-welding shape adjustment. The base plate pre-assembly product adopting the butt joint has positive promotion effects on the aspects of weld joint strength, welding quality, production efficiency and cost.)

1. The preparation method of the straddle type monorail vehicle framework bottom plate pre-assembly is characterized by comprising the following steps:

(1) processing a forged piece;

(2) fixing the bent plate and the processed forged piece on a welding tool through a pressing device, wherein the welding tool is provided with a welding anti-deformation design, and included angles are formed between the forged piece and the bent plate and a horizontal plane;

(3) setting the welding seam between the bent plate and the forging as a butt welding seam during welding; each butt welding seam is finished by adopting a mode of firstly welding at a flat welding position, then welding at a vertical welding position and then welding at a flat welding position, each butt welding seam needs to be continuously finished, and arc stopping can not be carried out during welding;

(4) and after welding is finished and the assembly is completely cooled, taking out the base plate pre-assembly, and checking a welding line without post-welding shape adjustment.

2. The method of making a straddle-type monorail car frame floor preassembly of claim 1, wherein the sequence of welding the welding areas between the four bent plates and the forging is: and finishing diagonal skip welding according to the welding area at the diagonal of the bottom plate pre-assembly.

3. The method for preparing the straddle-type monorail car frame bottom plate preassembly as claimed in claim 1 or 2, wherein the welding is performed by adopting a consumable electrode active gas (MAG) welding method, and a quenching arc guiding plate is additionally arranged on a tool during welding.

4. The method of making a straddle-type monorail car frame floor preassembly of claim 1 or 2, wherein the tack-down locations are welded: welding the flat welding position between the plane position of the bent plate and the forge piece; welding the vertical welding position: and welding the vertical welding position between the bending position of the bent plate and the forge piece.

5. The method of making a straddle-type monorail car frame floor preassembly of claim 4, wherein the vertical position welding is performed using a welding machine arc-closing current.

6. The method of making a straddle-type monorail car frame floor preassembly as claimed in claim 1 or 2, wherein the interlayer temperature of the weld does not exceed 150 ℃.

7. The method of making a straddle-type monorail car frame floor preassembly of claim 1 or 2, wherein the inspection weld: after welding, 100% ray inspection and 100% magnetic powder inspection are carried out on 4 welding seams.

8. The method of making a straddle-type monorail car frame floor preassembly of claim 1 or 2, wherein the forging and bent plate are at an angle of 5 ° to the horizontal.

Technical Field

The invention relates to a preparation method of a straddle type monorail car frame bottom plate pre-assembly, which is mainly used for welding production and quality control of key components of a straddle type monorail car bogie.

Background

Straddle type monorail car framework bottom plate subassembly in advance belongs to straddle type monorail car bogie reference part, and other spare parts of monorail car bogie all need use the bottom plate subassembly in advance to assemble as the benchmark promptly, except that welding quality requirement strict outer assembly precision and post-weld dimensional control requirement also very strict. Therefore, strict process implementation requirements are set for the production and the manufacture of the straddle type monorail car frame bottom plate pre-assembly aiming at the requirements of welding and size.

Regarding the production and manufacturing process of the straddle type monorail car frame bottom plate pre-assembly, the prior art adopts a lap welding (figure 3) process for a bending plate (figure 1) and a forging (figure 2), and the bottom plate pre-assembly is integrally machined after welding. The lapping process in the prior art has the advantages that: the material preparation process is simplified (the plate pieces can be assembled and welded after being blanked and bent); the assembly difficulty can be reduced, as long as the position of a welding line meets the requirements of a welding process, and the size requirement of each component after assembly is not high; the integral processing can ensure the dimensional precision of the product. However, the disadvantages of this prior art lap joint process are: the overall tooling costs are high and the overlapping weld joint pattern is not conducive to carrying shear stresses, resulting in reduced product load carrying capability.

Disclosure of Invention

The invention aims to provide a preparation method of a straddle type monorail car frame bottom plate pre-assembly, which solves the defects of overhigh processing cost and overlow weld joint bearing capacity of the prior art in the aspect of process, and improves and solves the prior art by taking 4 aspects of improving weld joint strength, improving welding quality, improving production efficiency and reducing production cost as starting points.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the preparation method of the straddle type monorail car frame bottom plate preassembly comprises the following steps:

(1) processing a forged piece;

(2) fixing the bent plate and the processed forged piece on a welding tool through a pressing device, wherein the welding tool is provided with a welding anti-deformation design, and included angles are formed between the forged piece and the bent plate and a horizontal plane;

(3) setting the welding seam between the bent plate and the forging as a butt welding seam during welding; each butt welding seam is finished by adopting a mode of firstly welding at a flat welding position, then welding at a vertical welding position and then welding at a flat welding position, each butt welding seam needs to be continuously finished, and arc stopping can not be carried out during welding;

(4) and after welding is finished and the assembly is completely cooled, taking out the base plate pre-assembly, and checking a welding line without post-welding shape adjustment.

Further, the sequence of welding the welding areas between the four bent plates and the forging is as follows: and welding is completed according to the welding area at the diagonal of the bottom plate pre-assembly.

Furthermore, the welding adopts consumable electrode active gas shielded welding, namely MAG welding, and a quenching arc plate is additionally arranged on the tool during the welding.

Further, the flat welding position welding: welding the flat welding position between the plane position of the bent plate and the forge piece; welding the vertical welding position: and welding the vertical welding position between the bending position of the bent plate and the forge piece.

Further, the vertical position welding uses the arc-closing current of a welding machine to carry out welding.

Further, the interlayer temperature of the weld does not exceed 150 ℃.

Further, the inspecting the weld: after welding, 100% ray inspection and 100% magnetic powder inspection are carried out on 4 welding seams.

Furthermore, 5-degree included angles are formed between the forge piece and the bent plate and the horizontal plane.

Compared with the prior art, the invention has the following advantages:

1. the strength of the welding seam is as follows: the strength of the butt welding seam is higher than that of the base material, and the strength of the welding seam of the lap joint can only reach 76% of that of the base material, so that the bearing capacity of the butt joint type welding seam is superior to that of the lap joint type welding seam. Meanwhile, the butt weld is superior to the lap joint weld in the aspects of shearing resistance, torsion resistance and the like, so that the butt weld is safer and more reliable, and the vehicle operation stability and safety are higher;

2. welding quality and weld joint detection: the butt joint detection means is more and more accurate, the defects in the welding seam can be detected by using ray inspection, and whether the welding quality meets the requirements or not can be effectively judged. And the lap joint can not realize accurate judgment of internal weld seam flaw detection. The influence of the welding defects on the vehicle operation safety can be reduced to the minimum through accurate and effective detection;

3. and (3) postweld profile adjustment: the butt joint is superior to the lap joint in welding deformation control, and the butt joint can realize the after-welding irregular forming process through welding reversible deformation. The gap between two parts of the lap joint must be controlled to be less than 1mm in order to ensure the welding quality, so that the technical scheme of prefabricated reversible deformation welding cannot be realized. The production efficiency is higher than that of the lap joint in the aspect of irregular shapes (by contrast, the production efficiency is improved by 34 percent). Meanwhile, the influence of the non-molding on the material is less, the plasticity and toughness of the original material are reserved, and the anti-fatigue property of the bogie component is facilitated;

4. the processing cost is as follows: the single piece processing cost of the forging is 5 times lower than that of the whole processing cost after welding. The cost control is more favorable and the product quality is not reduced.

In conclusion, the baseplate pre-assembly product adopting the butt joint has positive promotion effects on the aspects of weld joint strength, welding quality, production efficiency and cost.

Drawings

FIG. 1 shows a bent plate, which is formed by bending after laser cutting of the whole plate: (a) a top view; (b) cutting a drawing;

FIG. 2 is a forging: (a) a bottom view; (b) a side view;

FIG. 3 is a schematic view of a lap weld: (a) a top view of the pre-assembly; (b) enlarging the welding line;

fig. 4 is a schematic view of a butt-type joint: (a) a top view of the pre-assembly; (b) enlarging the welding line;

fig. 5 is a schematic view of the weld location area: (a) a top view of the pre-assembly; (b) a cross-sectional view of the weld;

FIG. 6 is an assembled schematic;

FIG. 7 is a schematic view of the weld run-out;

FIG. 8 is a schematic view of the arc striking and quenching plate being installed;

FIG. 9 is a schematic view of an in-package weld sequence;

wherein, 1, bending the plate; 2. forging; 3. lap welding; 4. butt welding; 4a, a flat welding area, 4b, a vertical welding area, 5 and a tool pressing device; 6. and an arc striking and extinguishing plate.

Detailed Description

The invention is further described below with reference to the accompanying drawings and examples.

The preparation method of the straddle-type monorail car frame bottom plate preassembly in the embodiment is described in terms of welding and material processing, and the specific contents are as follows:

changing the welding joint type from lap joint type to butt joint type (as shown in FIG. 4). The butt weld 4 is the welding of two workpieces at horizontally opposite positions (as shown in fig. 4b), and the depth of the weld can be the same as the thickness of the base metal by beveling the workpieces, so that the two workpieces can be connected seamlessly.

When welding each welding seam, the welding must be continuously finished, and the arc stopping is not allowed in the welding process. The welding operation is completed by welding the flat welding area 4a, the vertical welding area 4b and the flat welding area 4a, and the specific welding position area of the part is shown in figure 5.

During welding, firstly, four forgings 2 are placed at four corners of a welding tool (the tool is correspondingly improved according to the change of a base plate pre-assembly, the lap joint assembly mode is changed into a butt joint assembly mode, and the rest parts are not improved), and then the bent plate 1 is installed (see fig. 6). After all the components are assembled, the tooling pressing device 5 is used for pressing all the components, and after the components are pressed, due to the fact that the welding tooling has the welding anti-deformation design (the welding anti-deformation amount is determined according to a welding deformation amount experiment, the anti-deformation design can enable two components to be horizontal after welding is completed, later-stage shape adjustment is reduced, the welding anti-deformation is designed for offsetting the welding deformation, and an included angle of 5 degrees is formed between the forge piece 2 and the bent plate 1 and the horizontal plane (see figure 7) and is used for welding shrinkage deformation. A gas metal active welding (MAG welding) segment welding, which is located on the arc striking and extinguishing plate 6 at the end of the tool (see fig. 8).

When welding, all welding seams in the surface of the assembly are firstly finished, and the welding sequence is shown in figure 9 to carry out diagonal skip welding in alphabetical order (in order to control the integral diagonal difference of the components, the welding is carried out in a diagonal mode).

After the flat welding area 4a is converted into the vertical welding area 4b, the arc-closing current of a welding machine is needed to be used for welding, so that the whole welding line can be continuously and uninterruptedly welded, and therefore, a welding test plate is needed to be used for adjusting the arc-receiving current before welding, so that the arc-closing current can be quickly and accurately used during welding. The welding parameters are executed strictly according to the welding process rules. And the temperature between welding layers is not more than 150 ℃, so that the phenomenon that the toughness of the product is reduced due to overhigh hardness of the material caused by overheating so as to influence the operation safety of vehicles is avoided.

And after the assembly surface is welded and completely cooled, taking the straddle type monorail car frame bottom plate pre-assembly out of the tool. And (5) checking the welding quality of the welding seam and the size of the product. After welding, 100% ray inspection and 100% magnetic powder inspection are carried out on 4 welding seams. Due to the existence of welding reversible deformation during welding, the part is not required to be shaped after welding, and the length and width dimensions, the flatness and the relative position relationship of the four forgings of the bottom plate pre-assembly all meet the design requirements.

Secondly, material processing, namely, a mode that the forge piece 2 is processed firstly (the processing mode is the existing processing method and the processing is carried out on a numerical control processing center), and the machining is not carried out after welding. The selection of the material processing mode is determined on the basis of the easy control of welding deformation of the butt joint, which is different from the conventional integral processing after welding.

The following table is a comparison of the process of this example (butt joint) and the existing lap joint process:

the above description is only a preferred embodiment of the present invention, and should not be construed as limiting the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.