Carbon dioxide welding essentially belongs to what welding

There is a question in the welder's theory exam: CO2 shielded welding.

It is essentially MG welding. I didn't find a satisfactory answer to the question of MG welding on the Internet, my understanding is this, MIG's I refers to inertness, MAG's A refers to activity, and all of them are removed to MG welding, that is to say, MG welding includes MIG and MAG, which is a general term, and CO2 is an active gas, so it is more accurate to say that carbon dioxide shielded welding belongs to MAG welding.

The shielding gas for CO2 gas arc welding is carbon dioxide (sometimes CO2+AR gas mixture).It is mainly used for manual welding. Due to the special influence of the thermophysical properties of carbon dioxide gas, when using a conventional welding power supply, it is impossible to form a balanced axial free transition of the molten metal at the end of the welding wire, and it is usually necessary to use a short circuit and a molten droplet necking burst, so there is more spatter than the free transition of MIG welding.

However, if a high-quality welding machine is used, the parameters are selected appropriately, and a very stable welding process can be obtained, so that the spatter can be reduced to a minimum. Due to the low cost of shielding gas** used, the weld seam is well formed with short transitions, and the use of welding wire containing oxygen absorber results in a quality weld joint without internal defects. Therefore, this welding method has become one of the most important welding methods for ferrous materials.

Merit. 1. Reasonable design and free adjustment. Different discharge frequencies can be selected according to different metal materials to achieve the best repair effect.

2. The heat-affected area is small. There is no heat input during the instantaneous process of stacking, so there is no deformation, undercut and residual stress. No local annealing occurs and no re-heat treatment is required after repair.

3. Extremely small welding impact, this welding machine overcomes the impact of ordinary argon arc welding on the periphery of the workpiece in the welding repair process. It is also possible to repair the machining surface of the workpiece where there is no margin.

4. High repair accuracy: the thickness of surfacing welding is from a few microns to a few millimeters, only grinding and polishing.

5. High welding strength: due to the full penetration into the surface material of the workpiece, it produces a strong adhesion force.

6. Easy to carry: light weight (28 kg), 220V power supply, no working environment requirements.

7. Economy: Repair immediately on site, improve production efficiency and save costs.

8. One machine is multi-purpose: it can be used for surfacing welding, surface strengthening and other functions. By adjusting the discharge power and discharge frequency, the required thickness of the weld overlay and the reinforced finish can be obtained.

9. Hardness of surfacing layer and diversity of supplementary materials.

MAG (Metal Active Gas Arc Welding) welding is the English abbreviation of MIG/MAG arc welding. It is a mixed gas shielded welding that is mixed with a small amount of oxidizing gas (oxygen, carbon dioxide or their mixed gases) in argon. The commonly used gas mixture in China is 80% AR + 20% carbon dioxide, which is often called argon-rich mixed gas shielded welding due to the large proportion of argon in the mixed gas.

Peculiarity. The use of active gas mixture as shielding gas has the following functions:

1) Improve the stability of the droplet transition.

2) Stabilize the cathode spot and improve the stability of arc combustion.

3) Improve the penetration shape and appearance of the weld.

4) Increase the thermal power of the arc.

5) Control the metallurgical quality of the weld and reduce the welding defects.

6) Reduce welding costs.

MAG welding can be welded with short circuit transition, jet transition and pulse jet transition, which can obtain stable welding process performance and good welding joints, which can be used for welding in various positions, especially suitable for the welding of ferrous materials such as carbon steel, alloy steel and stainless steel.

1. Carbon dioxide gas shielded welding and arc welding are different in terms of welding speed, welding quality, welding cost, etc

1. Welding quality: carbon dioxide gas shielded welding is not easy to be invaded by air under gas protection, and the welding quality is better than manual welding.

2. Welding speed: carbon dioxide gas shielded welding has fast welding speed and high production efficiency due to the automatic feeding of welding wire, high current density and heat concentration, and the work efficiency can be increased by 2-5 times compared with arc welding.

3. Welding cost: carbon dioxide gas shielded welding adopts carbon dioxide shielded arc and molten pool, which is lower than the cost of arc welding, and carbon dioxide gas shielded welding consumes less electrical energy than arc welding in the welding process, and the cost is lower.

2. Advantages and disadvantages of carbon dioxide gas shielded welding:

1. Disadvantages of carbon dioxide gas shielded welding: due to the special influence of the thermophysical properties of carbon dioxide gas, when using conventional welding power supply, it is impossible to form a balanced axial free transition of molten metal at the end of the welding wire, and there is more spatter.

2. Advantages of carbon dioxide gas shielded welding: low welding cost; High production efficiency; Easy to operate; High crack resistance of welds; The deformation after welding is small.

3. Advantages and disadvantages of arc welding:

1. Disadvantages of arc welding: arc welding equipment will cause danger to people's lives, and labor protection equipment must be worn when welding.

2. Advantages of arc welding: electrode arc welding equipment is light and flexible to handle, so electrode arc welding can be carried out in any place with power supply. It is suitable for welding of various metal materials, various thicknesses and various structural shapes.

Similarities: 1. Electrode arc welding uses the coating to produce slag and gas protection.

CO2 welding and tungsten argon arc welding require shielding gas to protect the weld pool.

All three belong to the melting electrode welding.

2. The electrode arc welding core is used as a melting electrode, and CO2 welding uses the welding wire as an electrode to melt the electrode and fill the weld.

Tungsten TIG welding uses the self-fusing or filler wire of the base metal of the weld to form a weld after it is cooled as a liquid metal.

Differences: 1. Electrode arc welding core and CO2 welding wire are used as electrode dry potato benches to melt to form welds.

Tungsten argon arc welding tungsten electrode is used as an electrode, which plays a role in heating the base metal and welding wire. The electrode itself does not melt. It is a welding process that uses the self-melting of the base metal or the melting of the welding wire to form a filling liquid metal and filling the base metal.

2. The hand arc welding of the hand answer electrode adopts the form of scratching arc or direct contact arc striking and jet transition.

C02 welding uses contact arc starting. Short-circuit transition or particle jet transition form.

Tungsten argon arc welding adopts high-frequency arc striking. or scratch arcing.

3. CO2 welding shielding gas belongs to oxidizing gas, and tungsten argon arc welding argon gas belongs to inert gas.

Carbon dioxide welding is a commonly used welding method and is essentially gas shielded welding. It wraps the welding area with gas shielded material to prevent impurities in the air from entering the weld, thus guaranteeing the quality of the weld.

CO2 welding is an efficient, economical, and stable welding method that is suitable for the welding of a variety of metal materials. It mainly uses dust melting electrodes to complete the welding work, and after high temperature and oxidation, the metal materials in the welding area are melted and bonded together.

The advantages of carbon dioxide welding are fast welding speed, high welding quality, simple equipment, low cost, etc. It is widely used in automotive, aviation, manufacturing and other fields.

However, CO2 welding also has its limitations. For example, when welding materials that do not oxidize easily, such as stainless steel, argon or other gases need to be used for protection. At the same time, carbon dioxide welding is also prone to problems such as welding deformation and cracks, and it is necessary to strengthen welding technology and quality control.

In general, carbon dioxide welding is an important gas shielded welding method, which has a wide range of application prospects and technical development space. We need to study and apply CO2 welding technology more deeply to meet the requirements of Minbi for welding of different materials, and promote the industrialization process and technological innovation.

The arc welding method with carbon dioxide gas as shielding gas is known as carbon dioxide gas shielded welding, referred to as carbon dioxide welding.

Carbon dioxide gas shielded welding has the characteristics of no combustion

1.Carbon dioxide gas is cheap and easy to obtain, and consumes less electricity, which is an economical and convenient welding method for automatic production;

2.High production efficiency. The welding current density is large, the welding wire melting rate is high, the base metal penetration depth is large, for the steel plate of about 10 mm, it can be welded directly without opening the groove, and the slag after welding is very small, and the slag can be generally cleared, and the welding quality is stable;

3.The current density is large, the arc heat is concentrated, and the deformation of the workpiece after welding is small;

4.It is less sensitive to oil and rust, which can reduce the cleaning workload of workpiece and welding wire;

5.The hydrogen content of the weld metal is small, and the tendency to produce cold cracks is small when welding low-alloy high-strength steel.

6.There is a lot of spatter, the weld forming is not beautiful enough, and it takes time to clean up the spatter;

7.Carbon dioxide is weakly oxidizing, so it cannot be used to weld chemically active metals such as aluminum and magnesium.

The most significant differences between carbon monoxide welding and carbon dioxide welding are:

1) The thermal efficiency is different. The thermal efficiency of CO2 welding is high, which can achieve a fast welding speed; Whereas, carbon monoxide welding has a lower thermal efficiency and slower welding speed.

2) The welding hole shape is different. CO2 welding can produce smaller weld holes, while carbon monoxide welding tends to produce larger weld holes.

3) The welding penetration is different. Carbon monoxide welding generally has a deep weld penetration, whereas carbon dioxide welding has a generally shallow weld penetration.

4) The use environment is different. Carbon monoxide welding is suitable for indoor environments, while carbon dioxide welding can be performed outdoors as well as in poor gas environments.

Carbon dioxide gas shielded welding is one of the welding methods, which is a method of welding with carbon dioxide gas as the shielding gas. It is easy to operate in terms of application and is suitable for automatic welding and all-round welding. There can be no wind during welding, which is suitable for indoor work.

It is easy to operate in terms of application and is suitable for automatic welding and all-round welding. Poor wind resistance during welding, suitable for indoor operations. Due to its low cost, carbon dioxide gas is easy to produce and is widely used in large and small enterprises.

Due to the special influence of the zero thermophysical properties of carbon dioxide gas, when using a conventional welding power supply, it is impossible for the molten metal at the end of the welding wire to form a balanced axial free transition, and it is usually necessary to use a short circuit and a molten droplet necking explosion, so there is more spatter than the free transition of MIG welding. However, if a high-quality welding machine is used, the parameters are selected appropriately, and a very stable macro welding process can be obtained, so that the spatter can be reduced to a minimum.

Due to the low cost of shielding gas** used, the weld seam is well formed during the short-circuit transition of the early cavity cavity, and the use of welding wire containing oxygen absorber can obtain a high-quality welded joint with no internal defects. Therefore, this welding method has become one of the most important welding methods for ferrous materials.