How much tungsten is used to weld general stainless steel doors and windows with argon arc welding,

The shape of the tungsten needle will also increase its consumption, generally the cone surface is smooth, the tip has a small step, not only is not easy to bald, and the arc stabilization effect is better. Of course, no matter how well the tungsten needle is sharpened, it will still reach the melting point of tungsten due to too long welding time and excessive current, and it will be plasticized during the period, and under the dominance of surface tension, it will form a round bald shape. In addition, the evaporation of the welded material may also be formed by touching the tungsten electrode.

The welded material contains low ionization energy substances, such as surface galvanization, which will melt the tungsten electrode in an instant, which is the same as the effect of tungsten electrode DC welding aluminum, this element with strong discharge ability, can make the tungsten needle reach the melting point in an instant.

The doors and windows you are welding may be of inferior quality, and they contain too many substances with high discharge capacity or low boiling point, which makes the tungsten needle easily damaged.

The dosage depends on the welding amount and the quality of the tungsten electrode, the temperature is higher during welding, it can be used for a longer time, and the bad one will not take long to be bald. Welding habits are also related, such as poor distance control and tungsten electrode.

When the tungsten electrode and the weldment do not stick, the tungsten electrode becomes bald, indicating that there is a problem with the material of the tungsten electrode.

The needle is placed inside the tip of the pipette, which is not easy to bald, but the solder joint is not very good-looking.

Answer: DC is connected.

Analysis: When tungsten silver argon arc welding steel, titanium and other metal materials, the weld penetration formed when DC is connected is the largest, and the penetration depth is the smallest when DC is reversed, and the AC is in between. Due to the maximum penetration depth of the front and the smallest tungsten electrode burn-out loss, the DC positive connection should be used when welding steel, titanium and other metal materials in tungsten argon arc welding.

1. Tungsten argon arc welding is a method that uses argon as the shielding gas and tungsten electrode as the non-melting electrode, and heats and melts the base metal with the help of the arc generated between the tungsten electrode and the weldment (and the welding wire is also melted at the same time). Argon is used to protect the weld metal and tungsten electrode melt pool from oxidation by air in the arc heating area.

2. Advantages of general argon arc welding:

1) It can weld most metals and alloys except aluminum-tin, which has a very low melting point.

2) AC argon arc welding can weld aluminum and aluminum-magnesium alloys with relatively active chemical properties and easy to form oxide films.

3) No welding slag and no spatter during welding.

4) It can be welded in all directions, and the heat input can be reduced by pulse argon arc welding, which is suitable for welding stainless steel.

5) The arc temperature is high, the heat input is small, the speed is fast, the heat affected surface is small, and the welding deformation is small.

6) The amount of filler metal and addition is not affected by the welding current.

3. The applicable welding range of argon arc welding.

It is suitable for carbon steel, alloy steel, stainless steel, refractory metal aluminum and aluminum-magnesium alloy, copper and copper alloy, titanium and titanium alloy, as well as ultra-thin plate, and can be welded in all directions, especially for complex weldments that are difficult to access, etc.

Answer]: B, C

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Tungsten inert gas shielded welding.

1. It has the characteristics of electrode arc welding.

2 own characteristics:

1) The arc heat is concentrated, the welding heat input can be accurately controlled, and the welding heat affected zone is narrow;

2) No slag is produced during the welding process, no spatter, and the surface of the weld is smooth and clean;

3) There is no smoke and dust in the welding process, the molten pool is easy to control, and the quality of the weld is high;

4) The welding process is highly adaptable, and almost all metal materials can be welded;

5) The welding parameters can be accurately controlled, and it is easy to realize the full automation of the welding process;