What is the function of the electrode coating, and the role of the electrode coating

The coating that is press-applied to the surface of the solder core is called a coating. The coating of the electrode plays an extremely important role in the welding process. If the light electrode without coating is used for welding, during the welding process, the oxygen and nitrogen in the air will invade the molten metal in large quantities, oxidize and nitride the metal iron and beneficial elements such as carbon, silicon, manganese and so on to form various oxides and nitrides, and remain in the weld, causing slag inclusion or cracks in the weld.

The gas fused into the molten pool may cause a large number of porosity in the weld, and these factors can greatly reduce the mechanical properties (strength, impact value, etc.) of the weld and make the weld brittle. In addition, the use of light electrode welding, the arc is very unstable, the spatter is serious, and the weld forming is very poor.

In the process of practice, people find that if a coating composed of various minerals is applied on the outside of the light electrode, the arc combustion can be stabilized and the quality of the weld can be improved, and this kind of electrode is called coated electrode. With the continuous development of industrial technology, people have created high-quality thick coating welding rods that are now widely used.

1) Coating type: titanium type Main components of coating : titanium oxide 35% Welding power supply: DC or AC.

2) Coating type: titanium calcium type Main components of the coating : titanium oxide 30% or more, carbonate 20% or less Welding power supply: DC or AC.

3) Coating type: ilmenite type Main components of the coating: ilmenite 30% welding power supply:

DC or AC (4) Coating type: iron oxide type Main components of the coating: more iron oxide and more ferromanganese deoxidizer Welding power supply:

DC or AC.

5) Coating type: high cellulose sodium type Main components of the coating: more than 15% organic matter, about 30% titanium oxide Welding power supply: DC.

6) Coating type: high cellulose potassium type Main components of the coating: more than 15% organic matter, about 30% titanium oxide Welding power supply: DC or AC.

7) Coating type: low hydrogen sodium type Main components of the coating: calcium, magnesium carbonate and fluorite welding power supply:

DC (8) Coating type: low hydrogen potassium type Main components of the coating : calcium, magnesium carbonate and fluorite Welding power supply:

DC or AC.

9) Coating type: iron powder low hydrogen type Main components of the coating : calcium, magnesium carbonate, fluorite and iron powder Welding power supply: DC or AC.

10) Coating type: graphite type Main components of the coating: multi-amount graphite Welding power supply: DC or AC.

11) Coating type: salt-based Main components of the coating: chloride and fluoride Welding power supply: DC.

1.Protects the arc and the melt pool.

2.Metallurgical treatment.

3.Give the electrode good welding process performance.

4.Meet the special functions of some special electrodes.

It is mainly composed of reducing agent, after the success of the introduction, the chemical reaction will occur at high temperature, just like the change in the steelmaking furnace, the reducing agent in the coating will reduce the oxidized part of the iron at high temperature when the iron core is melted, and at the same time make the melted molten iron uniform, and the coating can form a protective umbrella in the channel of the molten iron flow under the action of the arc to avoid the molten iron from being oxidized by external again.

During welding, the coating acts as a protection and slag formation (metallurgical flux) in the welding pool.

The main purpose of drying the electrode before use is to remove moisture from the coating.

What are the main components of the coating on the surface of the electrode of the welding machine? What's the use?

The electrode is composed of two parts: the metal core in the center and the coating coating coating.

Welding core: It mainly plays the role of filling metal and conducting current.

Effect of the coating: (1) The slag and gas generated when the coating is melted isolate the arc space and the molten pool from the atmosphere;

2) The metallurgical effect of the coating ensures the deoxidation, desulfurization and dephosphorization of the weld metal, and adds the necessary alloying elements to the weld to make the weld have certain mechanical properties;

3) Make the welding rod have good welding process.

The effects of the electrode coating are as follows:

1. Arc initiation and arc stabilization, the arc stabilization column containing K and Na components in the coating is conducive to arc initiation and arc stabilization.

2. Deoxidation and desulfurization, SI, MN, A1, Ti and other elements can be added to the coating for deoxygenation, and human MN can be added for desulfurization. The most added deoxidizer is ferrosilicon, while ferromanganese is the only desulfurizer.

3. Protective effect, the coating is added with a gas-making agent, which can produce a shielding gas dominated by CO2 to protect the welding area from air invasion. The slag formed after the melting of the coating covers the surface of the weld and also protects the weld, slows down the cooling rate of the weld, and gives the escape of the lecon gas.

4. Improve the welding process and improve the welding productivity The coating contains suitable slag and thin slag components, so that the slag has the right viscosity and fluidity, and is convenient for welding. The coating sleeve formed during welding facilitates droplet transition, reduces spatter and heat loss, and thus improves welding productivity.

Welding electrode coating is a kind of surface protective film for welding materials, which is usually made from raw materials such as natural plant wax, synthetic wax and calcium powder. The surface of the electrode is generally coated with a protective film, which is the electrode coating.

The main function of electrode is to prevent moisture, rust and oxidation on the surface of the electrode, and to maintain the good welding performance of the electrode. In the process of electric welding, the welding material usually needs to be heated to a high temperature before it can be melted, so the electrode coating can also prevent the electrode from burning, volatilizing and decomposing at high temperatures, so as to ensure the quality and stability of electric welding.

In addition, the electrode coating can also prevent damage and contamination of the electrode during storage and transportation, prolonging the service life of the electrode. At the same time, after the welding is completed, the electrode coating can burn by itself, reducing the difficulty and cost of cleaning work and improving work efficiency.

In industrial production, the application range of welding electrode coating is very wide, and it is widely used in automobile manufacturing, bridge construction, energy industry, machining and other fields. The use of electrode coatings can improve the efficiency and quality of electric welding and promote the development of industrial production.

Ingredients: The composition of the coating includes minerals (such as marble, fluorspar, etc.), ferroalloys and metal powders (such as ferromanganese, ferrotitanium, etc.), organic substances (such as wood flour, starch, etc.), chemical products (such as titanium dioxide, sodium silicate, etc.).

Function: 1. Arc stabilization. Ensure the stable combustion of the welding arc and make the welding process stable.

2. Protect the arc and molten pool. Nitrogen, oxygen and other gases in the air are harmful to the metallurgical reaction of the welding pool, and the gas produced after the melting of the electrode coating can isolate the air and avoid harmful gases from invading the weld pool. When the electrode melts, it forms slag, which covers the surface of the weld and protects the weld that has not completely cooled.

Reduces the cooling rate of the weld seam and facilitates the escape of gases. Prevents the formation of porosity. Improves weld structure and performance.

3. The coating participates in complex metallurgical reactions, and the required alloying elements are infiltrated into the weld metal through the coating, which can play a role in controlling the chemical composition of the weld to obtain the required weld metal properties. Adding alloying elements such as silicon-manganese to the electrode coating can deoxygenation, desulfurization and dephosphorization and other harmful gases and impurities on the weld, and improve the quality and performance of the weld.