阅读说明：本技术 一种用于薄壁不锈钢与薄壁紫铜的等离子弧熔钎焊方法 (Plasma arc melting brazing method for thin-wall stainless steel and thin-wall red copper ) 是由 徐明亮 尚振一 徐文张 蒋坤松 赵孔标 汤小和 于 2021-08-26 设计创作，主要内容包括：本发明公开了一种用于薄壁不锈钢与薄壁紫铜的等离子弧熔钎焊方法,所述用于薄壁不锈钢与薄壁紫铜的等离子弧熔钎焊方法包括将薄壁不锈钢板和薄壁紫铜管的待焊区域20mm内的杂质清理干净,露出薄壁不锈钢板和薄壁紫铜管各自的金属光泽；使用脉冲等离子弧焊机利用斜椭圆单点停顿法进行焊接,在焊接过程中,垂直角度上,将焊丝放置在与薄壁不锈钢板上表面呈30度的位置,水平角度上,将焊丝放置在与薄壁紫铜管下表面的切线角度呈70度的位置；脉冲等离子弧焊机的钨极与焊丝处于同一平面内且与焊丝呈90度,所述钨极距离所述薄壁紫铜管4-6mm,所述钨极距离所述薄壁不锈钢板6-8mm；焊接熄弧,完成焊接；具有方法简单,降低焊接成本等优点。(The invention discloses a plasma arc melting and brazing method for thin-wall stainless steel and thin-wall red copper, which comprises the steps of cleaning impurities in 20mm of to-be-welded areas of a thin-wall stainless steel plate and a thin-wall red copper pipe, and exposing the respective metallic luster of the thin-wall stainless steel plate and the thin-wall red copper pipe; welding by using a pulse plasma arc welding machine by using an oblique ellipse single-point pause method, wherein in the welding process, a welding wire is placed at a position which is 30 degrees away from the upper surface of the thin-wall stainless steel plate in a vertical angle, and is placed at a position which is 70 degrees away from the tangent angle of the lower surface of the thin-wall red copper pipe in a horizontal angle; a tungsten electrode of the pulse plasma arc welding machine is positioned in the same plane with the welding wire and forms an angle of 90 degrees with the welding wire, the distance between the tungsten electrode and the thin-wall red copper tube is 4-6mm, and the distance between the tungsten electrode and the thin-wall stainless steel plate is 6-8 mm; arc quenching is carried out during welding, and welding is completed; the method has the advantages of simplicity, welding cost reduction and the like.)

1. A plasma arc melting brazing method for thin-wall stainless steel and thin-wall red copper is characterized by comprising the following steps:

cleaning up impurities in 20mm areas to be welded of the thin-wall stainless steel plate and the thin-wall red copper pipe, and exposing the respective metal luster of the thin-wall stainless steel plate and the thin-wall red copper pipe;

welding by using a pulse plasma arc welding machine by using an oblique ellipse single-point pause method, wherein in the welding process, a welding wire is placed at a position which is 30 degrees away from the upper surface of the thin-wall stainless steel plate in a vertical angle, and is placed at a position which is 70 degrees away from the tangent angle of the lower surface of the thin-wall red copper pipe in a horizontal angle; a tungsten electrode of the pulse plasma arc welding machine is positioned in the same plane with the welding wire and forms an angle of 90 degrees with the welding wire, the distance between the tungsten electrode and the thin-wall red copper tube is 4-6mm, and the distance between the tungsten electrode and the thin-wall stainless steel plate is 6-8 mm;

and (4) arc quenching during welding, and completing welding.

2. The plasma arc fusion brazing method for thin wall stainless steel and thin wall red copper according to claim 1, characterized in that the pulse plasma arc welder is LHW-200 pulse plasma arc welder, and the argon concentration is greater than or equal to 99.96%.

3. The plasma arc fusion brazing process for thin wall stainless steel and thin wall red copper according to claim 1, characterized in that the welding wire is a red copper welding wire with a diameter of 2 mm.

4. The plasma arc brazing process for thin wall stainless steel and thin wall red copper according to claim 1, wherein the taper of the end of the weld of the tungsten electrode is 40-60 degrees.

5. The plasma arc brazing process for thin wall stainless steel and thin wall red copper according to claim 1, wherein said "welding with an oblique ellipse single spot pause using a pulsed plasma arc welder" comprises:

the tungsten electrode and the welding wire are welded along the surface to be welded, the welding wire starts to move after being melted on the surface to be welded to generate a molten pool in the welding process, the welding route is in an oblique elliptical shape, in the process of moving in the oblique elliptical shape, the welding wire stops at one side of the thin-wall red copper tube, and the welding wire continues to move in the oblique elliptical shape after the diameter of the molten pool is observed to be 1-2 times that of the welding wire in the stopping process.

6. The plasma arc brazing process for thin wall stainless steel and thin wall red copper according to claim 5, wherein neither the tungsten electrode nor the welding wire is in contact with the weld puddle during welding.

7. The plasma arc brazing method for thin-walled stainless steel and thin-walled red copper according to claim 1, wherein during welding, the arc generated by the tungsten electrode needs to be mostly aligned with the thin-walled red copper tube, and when the arc is quenched during welding, the position of the welding gun is maintained, and the welding gun is lifted after the lagging gas-stopping protection function of the pulse plasma arc welding machine is finished.

8. The plasma arc fusion brazing process for thin wall stainless steel and thin wall red copper according to claim 1, characterized in that the thin wall red copper tube is replaced by a thin wall red copper plate.

Technical Field

The invention relates to the technical field of stainless steel and copper welding, in particular to a plasma arc fusion brazing method for thin-wall stainless steel and thin-wall red copper.

Background

The welding method for stainless steel and copper is oxygen acetylene welding, resistance butt welding, brazing, tungsten argon arc welding and the like, and the filling materials in the production are mostly silver-based copper welding wires or silver-based gaskets. Because the silver-based copper welding wire has the advantages of narrowest melting temperature, low melting point, electric corrosion resistance, excellent permeability and toughness, good fluidity and wettability, can be quickly welded and formed, and the welding is easier when the silver content is higher, the welding wire is an advanced and excellent welding device in foreign countries, the silver content of the filling material of the copper tube-stainless steel tube plate angle joint technology is mostly low or no silver, the domestic control of advanced materials leads our welding equipment to have certain difference with the foreign advanced welding equipment, if welding is carried out according to the foreign process requirements, the copper pipe is easy to burn through, therefore, the silver content of the silver-based copper welding wire used as the filling material in the copper tube-stainless steel tube plate angle joint technology at present is very high, so that the process requirement and the use requirement can be met, therefore, the welding cost of the copper tube-stainless steel tube is extremely high at present both at home and abroad.

Therefore, the plasma arc melting brazing method for the thin-wall stainless steel and the thin-wall red copper is provided, and the problems can be solved.

Disclosure of Invention

The invention aims to solve the technical problem that the welding cost is overhigh due to high silver content of a silver-based copper welding wire which is a filling material for a copper pipe-stainless steel pipe plate angle joint technology in China at the present stage, so that a plasma arc melting brazing method for thin-wall stainless steel and thin-wall red copper is provided, and comprises the following steps:

cleaning up impurities in 20mm areas to be welded of the thin-wall stainless steel plate and the thin-wall red copper pipe, and exposing the respective metal luster of the thin-wall stainless steel plate and the thin-wall red copper pipe;

welding by using a pulse plasma arc welding machine by using an oblique ellipse single-point pause method, wherein in the welding process, a welding wire is placed at a position which is 30 degrees away from the upper surface of the thin-wall stainless steel plate in a vertical angle, and is placed at a position which is 70 degrees away from the tangent angle of the lower surface of the thin-wall red copper pipe in a horizontal angle; a tungsten electrode of the pulse plasma arc welding machine is positioned in the same plane with the welding wire and forms an angle of 90 degrees with the welding wire, the distance between the tungsten electrode and the thin-wall red copper tube is 4-6mm, and the distance between the tungsten electrode and the thin-wall stainless steel plate is 6-8 mm;

and (5) completing welding.

Further, the pulse plasma arc welding machine is LHW-200 pulse plasma arc welding machines, and the argon concentration is greater than or equal to 99.96%.

Further, the welding wire is a red copper welding wire with the diameter of 2 mm.

Further, the taper of the end part of the welding part of the tungsten electrode is 40-60 degrees.

Further, the "welding using a skewed ellipse single-spot pause method using a pulse plasma arc welding machine" includes:

the tungsten electrode and the welding wire are welded along the surface to be welded, the welding wire starts to move after being melted on the surface to be welded to generate a molten pool in the welding process, the welding route is in an oblique elliptical shape, in the process of moving in the oblique elliptical shape, the welding wire stops at one side of the thin-wall red copper tube, and the welding wire continues to move in the oblique elliptical shape after the diameter of the molten pool is observed to be 1-2 times that of the welding wire in the stopping process.

Further, neither the tungsten electrode nor the welding wire can contact the weld puddle during welding.

Further, in the welding process, most of electric arcs generated by the tungsten electrode need to be aligned to the thin-wall copper tube, when the electric arcs are quenched in the welding process, the position of the welding gun is kept, and the welding gun is lifted after the lagging gas stopping protection function of the pulse plasma arc welding machine is finished.

Further, the thin-wall red copper tube is replaced by a thin-wall red copper plate.

The beneficial effects of the implementation of the invention comprise:

the invention has simple equipment and convenient operation, can reduce the welding difficulty between the stainless steel and the red copper, can quickly weld the stainless steel plate and the red copper pipe, has wide application range, does not need to fill silver, reduces the cost and meets the process requirement and the use requirement.

Drawings

FIG. 1 is a flow chart of the present invention;

FIG. 2 is a schematic of the present invention;

wherein corresponding reference numerals shall be: 1-thin-wall stainless steel plate, 2-thin-wall red copper tube, 3-welding wire, 4-welding track and 5-welding direction.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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 invention.

Examples

Referring to the attached drawings 1-2 of the specification, the technical problem to be solved in this embodiment is that, in the domestic copper pipe-stainless steel pipe plate angle joint technology at present, the silver content of the silver-based copper welding wire as the filling material is very high, which results in too high welding cost, so that a plasma arc fusion brazing method for thin-wall stainless steel and thin-wall red copper is provided, and the plasma arc fusion brazing method for thin-wall stainless steel and thin-wall red copper comprises the following steps:

cleaning up impurities in 20mm areas to be welded of the thin-wall stainless steel plate and the thin-wall red copper pipe, and exposing the respective metal luster of the thin-wall stainless steel plate and the thin-wall red copper pipe;

welding by using a pulse plasma arc welding machine by using an oblique ellipse single-point pause method, wherein in the welding process, a welding wire is placed at a position which is 30 degrees away from the upper surface of the thin-wall stainless steel plate in a vertical angle, and is placed at a position which is 70 degrees away from the tangent angle of the lower surface of the thin-wall red copper pipe in a horizontal angle; the tungsten electrode of the pulse plasma arc welding machine is positioned in the same plane with the welding wire and forms an angle of 90 degrees with the welding wire, the distance between the tungsten electrode and the thin-wall red copper tube is 4-6mm, and the distance between the tungsten electrode and the thin-wall stainless steel plate is 6-8 mm.

The pulse plasma arc welding machine is LHW-200, and the argon concentration is more than or equal to 99.96%.

The welding wire is a red copper welding wire, and the diameter of the red copper welding wire is 2 mm.

The taper of the end of the tungsten electrode at the weld is 40-60 degrees.

"welding using a pulse plasma arc welder using an oblique ellipse single spot pause method" includes:

the tungsten electrode and the welding wire are welded along the surface to be welded, the welding wire starts to move after being melted on the surface to be welded to generate a molten pool in the welding process, the welding route is in an oblique elliptical shape, in the process of moving in the oblique elliptical shape, the welding wire stops at one side of the thin-wall red copper tube, and the welding wire continues to move in the oblique elliptical shape after the diameter of the molten pool is observed to be 1-2 times that of the welding wire in the stopping process.

Neither the tungsten electrode nor the welding wire can contact the weld pool during welding.

During welding, most of electric arc generated by a tungsten electrode needs to be aligned to the thin-wall copper tube, when the arc is extinguished during welding, the position of a welding gun is kept, and the welding gun is lifted after the lagging gas-stopping protection function of the pulse plasma arc welding machine is finished.

The thin-wall red copper tube is replaced by a thin-wall red copper plate.

The manual plasma arc welding method is adopted, most of electric arcs aim at a copper pipe, the forward moving speed of a welding gun is high, in addition, the temperature of a molten pool is controlled to be proper in the welding process, the flowing condition of copper liquid in the molten pool needs to be closely noticed, the opportunity is mastered, a tungsten electrode is strictly forbidden to be in contact with a welding wire or a tungsten electrode and the molten pool in the welding process, a large amount of metal smoke is generated when the tungsten electrode is in contact with the welding wire and the molten pool in the welding process, and air holes or cracks are generated in a welding seam. If the phenomena of tungsten electrode, welding wire and molten pool occur, the welding must be stopped, and after the tungsten electrode is dressed again after being processed and ground, the welding can be continued. The temperature of the molten pool should be strictly controlled during welding, otherwise, non-fusion defects or burnthrough are easily generated. When the arc is extinguished during welding, the welding gun cannot be immediately lifted, and a lagging gas-stopping protection function is utilized to protect a molten pool and prevent gas holes from being generated;

the taper of the tungsten electrode is 40-60 degrees, the angle between the welding wire and the stainless steel surface is about 30 degrees, the distance between the tungsten electrode and the copper is about 70 degrees relative to the tangent line of the copper pipe and 4-6mm, the distance between the tungsten electrode and the copper is 6-8mm relative to the stainless steel, the wrist is used as an axis, the welding is carried out by adopting an oblique ellipse single-point pause method according to the size of a molten pool, the stop point is arranged on one side of the copper pipe, the size of the molten pool is observed during the pause time, and the diameter of the molten pool is preferably 1-2 times of the diameter of the welding wire.

In the description of the present invention, it is to be understood that the terms "coaxial", "bottom", "one end", "top", "middle", "other end", "upper", "one side", "top", "inner", "front", "center", "both ends", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "disposed," "connected," "secured," "screwed" and the like are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; the terms may be directly connected or indirectly connected through an intermediate, and may be communication between two elements or interaction relationship between two elements, unless otherwise specifically limited, and the specific meaning of the terms in the present invention will be understood by those skilled in the art according to specific situations.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.