What is electrode arc welding? How to choose electrode arc welding

Arc welding. It refers to the physical phenomenon of using the arc as a heat source and using air discharge to convert electrical energy into thermal energy and mechanical energy required for welding.

So as to achieve the purpose of connecting metals. The main methods are electrode arc welding and submerged arc welding.

Gas shielded welding, etc., it is currently the most widely used and important fusion welding method, accounting for more than 60% of the total welding production. Electrode arc welding is the most widely used welding method in industrial production, its principle is to use the heat generated by arc discharge (commonly known as arc combustion) to melt the electrode and the workpiece to each other and form a weld after condensation, so as to obtain a strong joint welding process. Electrode arc welding is to manually manipulate the electrode for welding work, and can carry out multi-position welding such as flat welding, vertical welding, horizontal welding and vertical welding.

In addition, because the electrode arc welding equipment is light and flexible to handle, the electrode arc welding can be carried out in any place where there is a power supply. It is suitable for welding of various metal materials, various thicknesses and various structural shapes. Safety features of electrode arc welding:

The no-load voltage of electrode arc welding equipment is generally 50V-90V, and the safe voltage that the human body can bear.

It is 30V-45V, which shows that manual arc welding equipment will cause danger to people's lives. Arc welding can be divided into manual arc welding, semi-automatic (arc) welding, and automatic (arc) welding. Automatic (arc) welding usually refers to automatic submerged arc welding - a light welding wire made of filler metal with a protective flux layer at the welding site.

The flux layer is inserted, and the arc is generated with the welding metal, the arc is buried under the flux layer, and the heat generated by the arc melts the welding wire, flux and base metal to form a weld, and the welding process is automated. The most commonly used is manual arc welding. <>

Welding process: manual arc welding consists of welding power supply, welding cable, welding tongs, welding rods, welding parts, arc formation loop, welding rod and workpiece contact ignite arc during welding, and then lift the welding rod and keep a certain distance, the arc burns stably under the welding power supply to provide a suitable arc voltage and welding current, resulting in high temperature, and the welding rod and welding parts are partially heated to a melting state. The molten metal at the end of the electrode and the metal of the weldment being melted are fused together to form a molten pool.

In welding, the arc moves with the electrode, and the liquid metal in the molten pool gradually cools and crystallizes to form a weld, and the two weldments are welded together. In welding, the core of the electrode melts and transitions to the molten pool in the form of molten droplets, while the electrode coating produces a certain amount of gas and liquid slag. The resulting gas fills the arc and around the molten pool, isolating the air.

Liquid slag is less dense than liquid metal and floats on top of the melt pool, thus protecting the melt pool. When the metal in the molten pool is cooled and solidified, the slag also solidifies to form welding slag covering the surface of the weld, which prevents the high-temperature weld metal from being oxidized and reduces the cooling rate of the weld. In the welding process, complex metallurgical reactions such as deoxidation, desulfurization, phosphorus and dehydrogenation are carried out between liquid metal and liquid slag and gas, so that the weld metal can obtain a suitable chemical composition and structure.

Electrode arc welding starts from the basis of welding arc, according to the principle of "cognitive, easy to learn, easy to master, and able to operate", from shallow to deep, step by step explains the process theory and practical skills of electrode arc welding. The main contents of this book include: basic knowledge of welding technology, electrode arc welding equipment, composition and classification of electrodes, models and grades of electrodes, welding process performance and selection principles of commonly used electrodes, correct storage and storage of electrodes, basic process knowledge of electrode arc welding, basic knowledge of welding metallurgy, organization and properties of welded joints, common welding defects of electrode arc welding and their prevention, typical pipe and tube sheet welding technology, carbon arc gouging.

Electrode arc welding is a kind of fusion welding, which is a welding method that uses two electrodes of electrode and weldment as power supply, and forms an arc between the electrode and the weldment with low voltage and high intensity current. <>

Electric welding technology: the abbreviation of arc welding technology.

Answer: Manual electrode arc welding is generally used in field welding construction operations, long-distance pipelines, pipeline installation and construction, and parts with high strength requirements. Electrode arc welding can be used in automobile manufacturing, pipeline engineering construction welding, bridge engineering construction welding, shipbuilding industry, and various hardware manufacturing industries, and is widely used.

Kiss! Welding comma, arc welding, submerged arc welding, and gas shielded welding, all belong to arc welding, which is currently widely used and more important fusion welding methods, which can reach more than 60% of the production volume of welding transportation. In addition, electrode arc welding is widely used in the industry, using arc discharge, generating heat to melt the electrode and the workpiece, and then it can be welded together after it cools.

Arc welding is to use the arc as a heat source, and then use the physical properties of air discharge to convert the inflow of electrical energy into the thermal energy and mechanical energy required for welding, so that the metal can be welded together. In addition, the equipment required for electrode arc welding is relatively lightweight, and the later handling is relatively flexible, so it is very simple to use, and the range is also tube, which is commonly used in the welding of metal materials and various shapes and structures. What are the characteristics of electrode arc welding:

1. The no-load voltage used in the electrode arc welding facilities and equipment is basically between 50 and 90 volts, and the voltage that the human body can withstand is between 30 and 45 volts. 2. Electrode arc welding can be divided into a variety of types, such as manual, semi-automatic, automatic, etc., each of which is used for different parts and welding effects. Among them, automatic arc welding refers to automatic welding, in the welding position, there will be a protective flux layer, and the whole process is automated.

3. Welding work is not a simple process, and it needs to be constructed by professionals to avoid greater potential safety hazards and affect future use. I hope I can help you! Have a great day!

Summary. Pro, electrode arc welding selection method:

How to choose electrode arc welding

Pro, electrode arc welding selection method:

1) Select the corresponding electrode type (category) according to the type of metal material to be welded. For example, when welding carbon steel or ordinary low-alloy steel, structural steel welding rods should be used.

2) The performance of the weld should be the same as that of the base metal, or the chemical composition type of the weld should be the same as that of the base metal to ensure the same performance.

For important structures with high requirements for weld performance (ductility and toughness), or steel and structures that are prone to cracks (large thickness, high rigidity, low temperature of the welding environment, etc.), alkaline electrodes, even ultra-low hydrogen electrodes and high-toughness electrodes should be selected.

Supplied by the welding power supply, a strong and long-lasting gas discharge phenomenon is generated between the two poles - called arcing.

According to the type of current, it can be divided into: AC arc, DC arc and pulse arc.

According to the state of the arc, it can be divided into: free arc and compression arc (such as plasma arc).

According to the electrode material, it can be divided into: melting electrode arc and non-melting electrode arc.

The strong and long-lasting discharge phenomenon between two electrodes with a certain voltage or between the electrodes and the weldments supplied by the welding power supply in the gaseous medium is called the welding arc.

There are several types of electric welding:

1. Arc welding is the most widely used welding method at present. It includes: hand arc welding, submerged arc welding, tungsten gas arc welding, plasma arc welding, MIG/MAG welding, etc. The vast majority of arc welding uses the arc burning between the electrode and the workpiece as the heat source.

2. This is a type of welding method that uses resistance heat as an energy source, including electroslag welding with slag resistance heat as an energy source and resistance welding with solid resistance heat as an energy source.

3. High-energy beam welding This type of welding method includes: electron beam welding and laser welding.

4. The energy source of brazing can be chemical reaction heat or indirect heat energy.

5. Other welding methods, mainly including electroslag welding and high-frequency welding with resistance heat as the energy source; Gas welding, pneumatic welding, and first-class welding with the ability to learn the welding energy of the stool; Friction welding, cold pressure welding, ultrasonic welding, and diffusion welding with mechanical energy as the welding energy source.

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, so that the arc space and the molten pool are isolated 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 electrode is made of a core and a coating. The weld core is made of high-grade and high-quality steel, while the coating includes marble, fluorite, sodium silicate, ilmenite, organics, and more. Common welding rods are stainless steel electrodes, carbon steel electrodes, and alloy steel electrodes.

The solder core is the metal core in the electrode that is coated with a coating. In manual welding, the solder core is the electrode and is also the filler metal. The coating is a coating layer that is pressed on the surface of the weld core, which is composed of a variety of ores, ferroalloys, cellulose and binders.