In my journey through the world of welding technology, I have gained a deep understanding of electric welding machines and their working principle and characteristics. These machines are essential for creating strong and reliable welds in various applications, from construction to manufacturing. By grasping how electric welding machines operate, I’ve been able to optimize my welding processes and enhance the quality of my work. In this article, I will explore the key principles and characteristics of electric welding machines, sharing insights that can help both beginners and experienced welders improve their skills and outcomes.

● Electric Welding Machine

The electric welding machine uses the high-temperature arc generated when the positive and negative poles are instantaneously short-circuited to melt the solder on the electrode and the material to be welded, and the purpose of combining the objects to be contacted. Its structure is very simple, it is a high-power transformer.

Electric welding machines can generally be divided into two types according to the output power source, one is AC power and the other is DC. They use the principle of inductance, the inductance will produce a huge voltage change when the inductance is turned on and off, and the high voltage arc generated when the positive and negative poles are short-circuited instantaneously is used to melt the solder on the electrode to achieve the purpose of atomic bonding. 

Features

⒈Advantages of electric welding machine: welding machine uses electric energy to convert electric energy into heat energy instantly. Electricity is very common. The welding machine is suitable for working in a dry environment and does not require too many requirements. Because of its small size, simple operation, convenient use, and fast speed, After welding, the advantages of strong welds are widely used in various fields, especially for parts requiring high strength. It can instantly connect the same metal materials permanently. After heat treatment, the welds will have the same strength as the base metal. The sealing is very good, which solves the problems of sealing and strength for the manufacture of storage gas and liquid containers.

⒉Disadvantages of the electric welding machine: During the use of the welding machine, a certain magnetic field will be generated around the welding machine. When the arc burns, radiation will be generated to the surroundings. The arc light contains infrared rays, ultraviolet rays, and other light species, as well as metal vapor and smoke, and other harmful substances. Therefore, adequate protective measures must be taken during operation. 

Welding is not suitable for high-carbon steel welding. Due to the process of crystallization, segregation, and oxidation of weld metal, the welding performance of high-carbon steel is poor, and it is easy to crack after welding, resulting in hot and cold cracks. Low carbon steel has good welding performance, but the process must be handled properly. Dusting and cleaning are more cumbersome. Sometimes the weld will have defects such as slag inclusion, cracks, pores, and undercuts, but the proper operation will reduce the occurrence of defects.

Principle

Electric welding works by generating a high-temperature arc when the positive and negative poles momentarily short-circuit. This arc melts the electrode and the base material, fusing them together. The electric welding machine has a simple structure—essentially a high-power transformer. It converts 220V or 380V AC into a low-voltage, high-current output, either DC or AC. Welding transformers are unique in that their voltage drops sharply once the arc starts. To control the welding voltage, not only is the input voltage stepped down, but the secondary coil includes tapped voltage adjustments, and the magnetic core position is also used to fine-tune the output.

The adjustable iron core welding machine is generally It is a high-power transformer, which is made by using the principle of inductance. The inductance will produce huge voltage changes when it is switched on and off. The high voltage arc generated by the instantaneous short circuit of the positive and negative poles is used to melt the welding rod. Solder to achieve the purpose of combining them. A voltage is applied between the electrode and the workpiece, and the arc is ignited by scratching or contacting, and the energy of the arc is used to melt the electrode and heat the base material.

Classification

1. The main electric welding machine used by industrial and mining enterprises are AC arc welding machine, DC electric welding machine, argon arc welding machine, carbon dioxide shielded welding machine, butt welding machine, spot welding machine, submerged arc welding machine, high-frequency seam welding machine, flash butt welding Machine, pressure welding machine, butt welding machine, laser welding machine.

2. There are two types of DC welding machines: one is the addition of rectifier components based on the AC motor, and the other is the DC generator. DC welding machines mainly weld non-ferrous metals and pig iron. The AC welder mainly welds steel plates.

3. Argon arc welding machine, carbon dioxide protection welding machine, high-frequency welding machine, flash butt welding machine. The argon arc welding machine and carbon dioxide gas shielded welding machine can mainly weld thin plates and non-ferrous gold layers below 2mm. The flash butt welding machine mainly connects copper and aluminum joints and other objects, and the high-frequency welding machine mainly welds steel pipes in the pipe factory.

4. Submerged arc welding mainly welds thick steel structure materials such as steel structural parts, bridge H steel, and I-beam girder.

5. Gas shielded welding machine: argon arc welding, carbon dioxide shielded welding, under the protection of gas, the welding machine will not be oxidized, the welding will be firm, the colored gold layer can be welded, and the thin material can be welded.

6. Laser welding machine: can weld the leads inside the transistor.

7. Butt electric welders: The cable chain factory mainly welds iron cables and other objects on anchors. It can be docked with Yuangang, etc.

● Laser Welding Machine

A laser welding machine, also known as laser welding machine and laser welding machine, is a machine used for material processing laser welding.

Working Principle

Laser welding is the use of high-energy laser pulses to locally heat the material in a small area. The energy of the laser radiation diffuses into the interior of the material through heat conduction, and the material is melted to form a specific molten pool. It is a new type of welding method, mainly for the welding of thin-walled materials and precision parts, and can realize spot welding, butt welding, stitch welding, sealing welding, etc. Small deformation, fast welding speed, smooth and beautiful welding seam, no need or simple treatment after welding, high welding seam quality, no pores, precise control, small focusing spot, high positioning accuracy, and easy automation.

Main Species

Laser welding machine is also often called laser welding machine, energy negative feedback laser welding machine, laser welding machine, laser welding machine, laser cold welding machine, laser argon welding machine, laser welding equipment, etc. According to its working method, it can often be divided into laser mold welding machine, automatic laser welding machine, jewelry laser welding machine, laser spot welding machine, optical fiber transmission laser welding machine, galvanometer welding machine, hand-held welding machine, etc., special laser welding equipment There are sensor welding machines, laser welding equipment for silicon steel sheets, and laser welding equipment for keyboards.

Laser Welding Machine Parameters

Power Density

Power density is one of the most critical parameters in laser processing. With higher power densities, the surface layer can be heated to the boiling point in the microsecond time range, resulting in a large amount of vaporization. Therefore, high power density is beneficial for material removal processes such as punching, cutting, and engraving. For lower power density, it takes several milliseconds for the surface temperature to reach the boiling point. Before the surface vaporizes, the bottom layer reaches the melting point, which is easy to form a good fusion weld. Therefore, in conduction laser welding, the power density is in the range of 104~106W/cm2.

Pulse Shape

Pulse waveform is an important issue in welding, especially for sheet welding. When a high-intensity beam hits the surface of the material, some of the energy on the metal surface will be reflected and lost, and the reflectivity varies with the surface temperature. During a pulse, the reflectivity of the metal varies greatly.

Pulse Width

Pulse width is one of the important parameters of pulse welding. It is not only an important parameter different from material removal and material melting, but also a key parameter that determines the cost and volume of processing equipment.

Effect of Defocus Amount

At the laser focus point, the power density is extremely high, which can cause the material to vaporize and form a hole. Away from the focus, the energy distribution becomes more uniform. There are two types of defocusing: positive and negative. When the focal point is above the workpiece, it’s called positive defocus; below it is negative defocus. According to geometric optics, if the distance to the welding plane is equal, both types can have similar power densities. However, the molten pool differs in shape. Negative defocus results in deeper penetration due to the way the molten pool forms.

● The Difference Between Laser Welding Machine And Electric Welding Machine

The spot welding machine is a resistance welding method that assembles the weldment into a lap joint, and presses it between two cylindrical electrodes, and uses resistance heat to melt the base metal metal to form a solder joint. Spot welding is mainly used for thin plate welding. The process is generally: pre-pressing to ensure good contact between the workpieces; electrification to form a nugget and plastic ring at the weld; power-off forging, so that the nugget cools and crystallizes under the continuous action of pressure, forming a dense structure without shrinkage holes and cracks of solder joints.

Differences:

1. Laser welding machine

The welding equipment has strong skills, obvious advantages, and accounts for a large proportion of welding processing. The laser beam is mainly used as the welding power. When the welding head is impacted, the beam can be collected by reflection or the lens can be cast on the welding seam, and then the welding is performed and can be used for welding. Optical communication devices, IT, medical, electronics, batteries, etc.

2. Spot welding machine

The welding equipment used by spot welding machines in the past has a simple process and is economical. It is suitable for most welding connections and does not require too many skills. Therefore, this equipment is one of the methods in the welding industry, using manual or program work. , Of course, the spot welding machine also has a laser spot welding machine. The items welded by the laser spot welding machine are well welded, without pollution, and the degree of damage is low.

Feature Difference:

1. The electric welders machine will not deform the welded parts due to the characteristics, the welding depth and width are good, the welding seam strength is high, the welding speed is fast, the accuracy of the processed components is high, and after the welding is completed, there is no need to do after-treatment, Compared with the spot welding machine, the welded parts are more beautiful.

2. Spot welding is a messy method. The same structural parts welded in the same batch will have welding seam problems, which will be superimposed on the street, which will affect the appearance and need to be dealt with. At the same time, the image of welding deformation often occurs, and the laser welding machine can reduce the problem of deformation.