principle

Electrode arc welding is the use of stable burning arc established between the electrode and the workpiece, so that the electrode and the workpiece melt, so as to obtain a solid welding joint process method. During the welding process, the coating continuously decomposes and melts to generate gas and slag, which protects the electrode end, arc, molten pool and its nearby areas to prevent harmful pollution of the atmosphere to the molten metal. The welding core also melts continuously under the action of arc heat and enters the weld pool to form the filler metal of the weld.

peculiarity

1. Compared with other arc welding methods, electrode arc welding has the following advantages:
1. The equipment is simple, the operation is flexible and convenient, the adaptability is strong, the accessibility is good, is not limited by the site and the welding position, and the welding can generally be performed in the place where the electrode can be reached, which are important reasons why the electrode arc welding is widely used.
2. Weldable metal material is wide, in addition to insoluble or easily oxidized metals, almost all metals can be welded.
3. The assembly quality requirements of the joint are low. During the welding process, the arc is manually controlled by the welder, and the welding process parameters can be modified by timely adjusting the arc position and rod speed, which reduces the quality requirements for the assembly of the joint.
Second, compared with other arc welding methods, electrode arc welding has the following disadvantages:
1. Low welding productivity, high labor intensity, compared with other arc welding methods, the welding current is small, and the welding rod must be replaced after each welding, and the slag needs to be cleaned after welding, low production efficiency and high labor intensity; And arc strong, smoke and dust.
2. The weld quality is highly dependent on people. Due to the manual operation of welding rods, there are requirements for the operation skills, working attitude and field play of welders.

course

Welding electrode arc welding consists of welding power supply, welding cable, welding pliers, welding electrode, welding parts, arc circuit, welding electrode and workpiece contact ignition arc, and then lift the welding electrode and maintain a certain distance, arc stable combustion in the welding power supply to provide appropriate arc voltage and welding current, high temperature, welding electrode and welding parts local heating to melt state. The molten metal at the end of the electrode and the molten part metal fuse together to form a molten pool. In welding, the arc moves with the electrode, the liquid metal in the molten pool gradually cools and crystallizes to form a weld, and the two welds are welded together.
In welding, the welding core of the electrode is transferred to the molten pool in the form of droplet after melting, and a certain amount of gas and liquid slag are produced by the coating of the electrode. The resulting gas fills around the arc and molten pool, trapping air. The liquid slag is less dense than the liquid metal and floats above the molten pool to protect the molten pool. When the metal in the molten pool cools and solidifies, the molten slag also solidifies to form welding slag covering the weld surface, preventing the high-temperature weld metal from being oxidized, and reducing the cooling speed of the weld. In the welding process, the liquid metal and the liquid slag and gas are deoxidized, desulfur, dephosphorus, dehydrogen and other complex metallurgical reactions, so that the weld metal can obtain the appropriate chemical composition and organization.