- Welding machine-transformer
- Welding machine-rectifier
- Welding machine-inverter
- Semiautomatic welding machines
- Argon arc welding machine
- Spot welding machine
- Gas welding machine
- Plasma welding machine for metals
Metal welding appeared a little over 100 years ago, but has already become an integral part of life. This is an excellent method of permanently connecting metal parts, which is used very widely due to its reliability, speed and minimal cost. Welding is used in a wide variety of areas – from the creation of large-scale structures of many tons to microelectronics. Let’s figure out what kind of welding machines exist, evaluate their pros and cons.
The most traditional type of electric welder is the transformer. The main element of the device is a step-down transformer, which converts the voltage of the electrical network into values that are needed for welding metal. The most famous technique for changing amperage is winding displacement. The gap between the windings changes – the current also changes. The efficiency of such a device reaches 90%, but part of the energy will be spent on heating. The transformer is inexpensive, reliable and durable, but today the scope of such devices is reduced due to the existing shortcomings. The disadvantages include the large weight of the device, the need to use special electrodes for alternating current. In addition, to work with such a welding machine requires considerable experience, otherwise the quality of the seam can seriously suffer.
In general, this is an improved version of the transformer welding machine. The welding seams created by the rectifier will be of better quality, the apparatus itself is inexpensive, durable, and reliable. The device includes a step-down transformer, a rectifier (diode unit), elements for protection, regulation and starting. The device converts alternating current into direct current, which guarantees a stable and even arc. This reduces metal spatter and can work with any electrodes. The rectifier allows you to work with various types of metal. Rectifier welding machines are used quite widely, but they also have drawbacks: heavy weight and serious “voltage drop” in the electrical network during operation.
These welding machines are also called pulse welding machines. Inverters are considered to be one of the most popular welding devices today. They weigh, in contrast to the above two types of devices, a little, are generally available and reliable. The welding inverter includes a power transformer that brings the voltage to the desired value, a choke-stabilizer and an electrical circuit block. The welding transformer is used at high frequency, it is much lighter and more compact. The advantages also include improved arc quality, reduced metal spatter, and improved efficiency. An inverter is easier to work with than a rectifier and transformer. There are practically no disadvantages of inverter welding machines; only a rather high cost can be attributed to such. The main thing is to carefully store the device in a heated room, protect it from moisture, dust and use special means to protect against power surges.
Semiautomatic welding machines
Semi-automatic welding machines are more complex devices than those listed above. The structure includes: a rectifier, a transformer, a drive that feeds the wire, a gas cylinder, a hose with a torch. Semi-automatic machines can work without gas, with gas or switch to different modes. If gas is not used, flux cored wire is required. The advantages of semiautomatic devices include high productivity, as well as a high-quality seam and work with various metals. By cons – high consumption of materials for waste and metal spraying.
Argon arc welding machine
Such a device using a tungsten electrode includes a set of torches used with different voltages, a control circuit, an alternating or direct current source for welding, a device for regulating work, an arc stabilizer. Argon-arc devices are used if it is necessary to weld non-ferrous metals with high quality. The advantages of such welding machines include the use of explosion-proof and non-combustible gas, the ability to weld parts with thin walls, and clean and high-quality arc welding technology. The seam is aesthetic and highly durable, and there are no sparks during operation. The disadvantages of argon-arc devices include the high cost of all equipment, low productivity, special requirements for the experience of the welder, the inability to work in a crosswind.
Spot welding machine
It is used for resistance welding of thermomechanical class. The parts are located between the electrodes, shrink, heat up, and then reliably connect, deforming together. Parts are heated to a plastic state using an instant pulse of welding current. The advantages of spot welding include the strength of the seam, ease of achieving automation, and cost effectiveness. However, such a weld seam turns out to be leaky, therefore it is not widespread..
Gas welding machine
In this case, flammable gases such as acetylene, hydrogen, natural gas are used. In air, such gases burn well. The technology of using a gas welding machine itself is simple. The advantages also include the absence of the need for a source of electric current, that is, you can work almost anywhere. In addition, the seams are durable and of high quality. But gas welding is done only by hand, the speed of work is low, as well as productivity. It is also important to accurately regulate the power of the burner, to devote enough time to preparing the parts..
Plasma welding machine for metals
In this case, the melting of the metal is carried out using a plasma stream, that is, a gas with charged particles that conduct an electric current. The arc temperature in such cases can reach tens of thousands of degrees. Plasma welding is one of the most modern methods; such a device is safe and economical to operate. Cylinders with acetylene, oxygen, propane are used. The device is mobile, the welding seam is minimal, since the metal is practically not deformed. However, it is expensive to build the apparatus and is still used mainly by professionals..