Welding machines: types, types, varieties - Setafi

Welding machine - a mechanism, device, tool for reliable connection of metals by heating / melting them with an electric arc.

The welding machine is used in production, industry, repair, construction, economy. If you have not dealt with welding machines before, then this article is for you.

Below we will analyze what PV is in welding, what welding modes are, how they differ, what types welding machines exist, the principle of operation of different types of welding, how different types of welding devices.

What is PV?

PV - duration of inclusion. This is an indicator that is measured as a percentage and determines how long the welding machine can work. Let's look at an example:

You bought welding with 50% duty cycle. This means that in a conditional 10 minutes, the device will cook metal / work for 5 minutes and rest / cool down for 5 minutes.

For industrial welding machines, the duty cycle can reach up to 100% - continuous operation. Household models can reach up to 70%.

Welding modes

There are four welding modes:

• MMA
• TIG
• MIG
• MAG

The first welding mode is ordinary welding, an electrode is used, there is an arc. The most popular welding mode - most often found in inverter welding machines.

TIG is the same welding mode with an arc electrode, but in gas. That is, an inert gas is supplied to the handle with an electrode through a hose that does not allow the gas to oxidize.

MIGs are used in semi-autos. Welding occurs due to the melting of steel / copper wire due to the high current strength. A protective gas (argon, carbon dioxide) is supplied to the molten wire, it prevents the metal from oxidizing, protects the system from debris and interference. MAG is also used in inverter semiautomatic devices. MAG differs from MIG in that it does not use a shielding gas, that is, it simply boils the metal with a wire through which a high current is applied.

What are the types of welding machines?

In total, there are four main types of welding machines:

• transformer welding.
• Rectifiers.
• inverter welding.
• Semiautomatic.
• Plasma cutters.
• Spotter - devices for spot welding.

You can also select universal welding machines. They work in all modes, suitable for welding ferrous, non-ferrous, thin-sheet metals. The universal ones also have a rectifier to convert alternating current to direct current.

Let's analyze each type separately.

Welding transformers

This is the basic type of welding using electrodes. The transformer is supplied with electricity from the network. As it passes through the transformer, the voltage drops and the current rises. Electricity is supplied intermittently. Because of this and the low level of protection, transformer welding machines are not popular.

Welding rectifiers

In fact, these are the same transformers. The voltage of electricity from the network decreases, the current increases, but in addition it passes through a rectifier made of transistors. This is how rectifiers produce direct current. Electrodes are also used for welding, but it is also possible to use wire.

Inverter welding machines

Inverter welding is equipped with automatic control, a transformer for changing voltage, and rectifiers for generating direct current. Inverters have the highest power rating, they are compact, weigh little. The main mode of operation of inverters is MMA, but there are models that operate in several modes. They cook with electrodes. The type and diameter of the electrode is not important. Inverters are universal, and therefore the most popular among all types of welding.

They are equipped with additional protection against unstable voltage, short circuit. Unlike transformers and rectifiers, their arc is constant and stable. Due to their small size and light weight, they are easy to transport.

The disadvantage of inverters is poor protection against dust and moisture. Most models are not well protected from dusty or humid air, so do not use inverter welders in dusty environments/those with relative humidity above 85%.

Inverter semi-automatic machines for car repair

Most often, when repairing a car body, semi-automatic welding is used. Semi-automatic machines can be with a transformer, rectifier or inverter. Inverter models are more convenient and popular. Semiautomatic machines are welded with wire. The wire can be steel, aluminum or stainless steel. Steel is used only for ferrous metals. The diameter of the wire varies depending on the type, but ranges from 0.5-2 millimeters, so a thin and even trace is obtained from semi-automatic welding.

To use semi-automatic devices, a shielding gas cylinder is required. Argon gas or carbon dioxide is used. Argon is only for welding aluminum blanks, carbon dioxide is for steel, iron. Why do you need gas in a semi-automatic? The gas protects the weld metal from oxidation upon contact with air. The operating mode with shielding gas is called MIG, without shielding gas is called MAG. The first does not care about the thickness of the material, the second is effective when welding ferrous metals.

Everything is regulated in semiautomatic devices - gas supply, current strength, voltage, wire feed. Universal semi-automatic machines can even weld aluminum blanks. The main advantage of semi-automatic machines is the quality of the seams, they are thin, even and durable. Also, a plus can be called the mode of operation with a protective gas - it does not allow the material to oxidize, so thin sheet metals can be welded with an inverter semiautomatic device.

Plasma cutters

Plasma cutters can cut, weld metals of different thicknesses. For this they use air. Ordinary air from the atmosphere is sucked in, passes through the device and enters the plasma torch - the working part, the burner. There, the air is heated by an electric arc, which produces a plasma cutter. The air is so hot that it turns into plasma. Its temperature reaches 30,000 degrees or higher in professional plasma cutters. Because of this, the plasma cutter easily cuts any metal. Household models (power up to 90 amperes inclusive) can cut three-centimeter metal. The power of professional plasma cutters reaches 170 amperes, they can cut even five-centimeter metal.

When choosing a plasma cutter, pay attention to its duty cycle (on-time) and cutting speed.

Spotters for fixing dents

Spotters are specialized devices for welding thin sheet metal of cars, body repair. Spotters are a system of a power source, connecting cables, a rectifier, a working handle / gun, and a power button. Additionally, the spotters have nozzles - a reverse hammer.

Works in the same way as a conventional inverter, but is used for other purposes. A chain is created from the cooked material through the mass, welding cables, power source to the working part. A nozzle / sting / reverse hammer is put on the working part. To use the device, you need to give a short but powerful impulse, then the tip of the handle is welded to the dent in the body. Pull on the handle to pull out the dent.