A huge amount of equipment has already been created for welding. With these devices, you can work with coated electrodes or with a special wire, which is continuously fed into the working area. These are effective devices, and among the shortcomings, only large weight and bulky sizes are noted. Also, this equipment will be difficult for beginners to master in this matter.
In addition, not all work can be performed using such transformer apparatuses.
Relatively recently, a new type of equipment appeared - inverter welding semiautomatic device. Let's try to understand the principles of work, find out the circuit of this device, as well as the features of this group of devices.
The principle of operation of inverter equipment
These are one of the youngest and very promising devices. Their serial production began only in the 80s. These were rectifiers equipped with a transistor inverter. In this device, electricity can change its characteristics up to several times. The scheme of the welding semiautomatic device allows you to see all this more clearly.
Initially, the current is rectified as it passes through the semiconductor elements. Then smoothing occurs using a filter system. Further, a direct current of standard frequency already changes its state to alternating, but its frequency is already much higher. After the frequency changes, the current is supplied to a small transformer, where the voltage decreases and the current increases. Then high-frequency filters and rectifiers are connected, which form an electric arc.
Advantages of Inverter Welders
Among the pluses, weight is noted. These are quite compact devices. Here you can apply various types of electrodes. This allows you to perform work on cast iron and non-ferrous metals. Inverters also have a higher efficiency. It can reach 85%. Profitability is also one of the advantages, and the ability to smoothly adjust the operating current, a stable arc are suitable for all types of operations.
For beginners, an inverter-type welding semiautomatic device can significantly simplify the work. In the hands of a professional, this high-frequency device is able to produce high-quality and most reliable seams.
disadvantages
The main drawback is the rather high price.
The cost is usually significantly higher than the price of transformer equipment. Repair will also be expensive if the device suddenly fails. For example, a block of power transistors is a third of the cost of the device.
In addition, the device does not like dust. Coolers for cooling are installed in the case - dust is sucked in in huge quantities. There may be metal dust in the air, which can cause short circuits.
Among the shortcomings, professionals note complex electronics, which are very sensitive to low air temperatures and moisture. There is a risk of condensation. There may also be some problems with work in the winter, and the device also requires proper storage.
Semi-automatic welding inverter
Semiautomatic machines differ from simple inverter welding devices by the presence of a special electrode wire feed mechanism to the welding site. To start the feed, the specialist pulls a special trigger. The area where the work is carried out is necessarily blown with protective gases. It can be helium, argon or carbon dioxide in the case of MAG or MIG systems. Household appliances work with carbon dioxide. Argon for homework is too expensive, and it is needed for operations with aluminum or stainless steel.
Semiautomatic device
Whichever welding semiautomatic device you choose, they all consist of a source for creating an electric arc, gearbox and motor, a torch with a sleeve, a cable for connecting to a part with a clamp. There is also a sleeve for gas supply, a cylinder with a reducer, as well as a control system.
Equipment advantages
Such a welding semiautomatic device allows you to work in various conditions - for this the device has a fairly wide range of settings. With their help, you can very simply select the desired mode of operation.
The arc can be observed at any position of the torch. Plus specifically inverter models - the ability to operate in any position. This is necessary for working in fairly inaccessible places.
This equipment can operate with thin-sheet materials or with those that are difficult to weld. If there is a need for welding more massive parts, then you can work without gas at all. The gas is designed to remove oxygen to prevent oxidation of the metal. The reaction with oxygen during welding leads to weld slag, films, and other troubles that affect reliability.
With devices you can use a variety of types of wire. Settings allow you to adjust the currents in a fairly wide range. So, using a welding semiautomatic device of this type, you can even perform bodywork. High precision welding is needed there - the inverter unit gives such accuracy.
disadvantages
The first minus is the price. Next comes the price of consumables, in particular the cost of gases is also quite high. To use such welding technology, either gas cylinders are needed, or equipment must be connected to the gas network. It is also an almost complete lack of mobility. Also, the welding semiautomatic device does not allow working with it on the street, and if it is possible to work, it is very inconvenient - it is necessary to protect the torch from blowing it in the wind.
How to choose the right model
As in the case with any other equipment, here the devices are also conditionally divided into professional and amateur devices. But do not think that amateur devices have truncated functionality. Not. In terms of functionality, household models are not much inferior to a professional group. Just an amateur inverter is designed for small loads. Work involves small-time approaches. The household model is not able to withstand an 8-hour shift. Many devices are equipped with additional functions that make working with them easier and better.
Many of the devices on the market can be purchased for the garage or for the home. The semiautomatic welding circuit can operate from a household electrical network. If there is a need to perform work away from outlets, then the equipment is equipped with a function of work from diesel generators.
You need to choose according to some important factors. Let's take a closer look at them.
Voltage
Semi-automatic devices are powered from a single-phase or three-phase network.
But for domestic use, a device under 220 V.
Many of the products on the market today are very sensitive to unstable voltages. They regularly fail or simply do not cook. Repairing a welding semiautomatic device is an expensive pleasure, so manufacturers equip their devices with surge protection. A household appliance often has an extended range of 15%. And professional ones can work at voltages of 165-270 V. There are inverter models that work great at low rates.
Open circuit voltage
This is more relevant for conventional welding machines. This characteristic shows how one or another model can ignite, and then maintain the burning of the arc. These parameters are limited by state standards at 80 V in the case of alternating currents and 90 V for direct current. Practice shows that the device can ignite an arc of 30 V. These are smart systems with electronic control. Among welders, it is believed that the higher the voltage at idle, the better the apparatus.
Power
Manual welding semiautomatic device contains all the data about the device. The maximum power consumption for this type of work is also indicated there. This figure also corresponds to the peak load on the network. This power is indicated either in kW or in kVA. The first option indicates active power, while the second measures total power. If you know how much this or that device consumes, you can precisely control the correct connection.
Even if the device can operate normally at low voltages, performance may drop. Knowing this, it is advisable to purchase a more powerful welding semiautomatic device (which one to choose depends on the goals). Experts say that the power margin should be at least 30%. Also, do not use the device to the maximum of its capabilities.
Real power indicators can only be determined by the strength of the current that it can produce. It depends on this characteristic with what thickness of metal this or that model can work. The maximum electrode thickness also depends on this.
For domestic purposes, an aggregate of up to 250 A is enough. What can such a welding semiautomatic device do? Owner reviews let you know what to expect. So, the maximum thickness of the metal is 6 mm, and the diameter of the electrode is 4 mm.
Working time
This is the most useful and most important information for those who select this equipment. This option allows you to evaluate performance. Engineers take a duty cycle, which is limited in time, and divide in percentage - how much a particular model can work without interruptions, and how much the machine needs to rest, so that later it will not be necessary to repair the welding semiautomatic device. For example, in European countries they count 10 minutes each. In our country, take 5 minutes as a basis. If the air defense is 30%, then the European model will turn off after 3 minutes of continuous operation, and it will be possible to restart the device only after 7 minutes. Of course, practice shows that no one works like that.
Possibility of work from the generator and additional functions
Power from the generator is an option. However, not every device has it. Modern welding units are often equipped with other pleasant options. So, for example, “Hot start”, “Forcing the arc”, “Anti-sticking” and others - all this is inalienable in the case of inverter systems. Do not pay attention to them - they are by default.
If you need a welding semiautomatic device, which one to choose?
One that has a wide range of adjustments, an overload protection system. Also, the unit must be safe, maintainable, ergonomic.
Mechanics
Devices differ in equipment, level, cost. The mechanics are also different in type. So, for household appliances, the pushing mechanism is mainly used as a wire feed device. Here, the system simply pushes the welding wire into the sleeve, which can sometimes cause jams.
The pulling mechanism is located in the handle of the burner, and models of the middle price range are equipped with it. The wire extends either from a coil located in the housing, or from a small one, which can be installed in the handle.
There is also a push-pull drive. They are equipped mainly with expensive, professional models. Here two devices work synchronously.
As for the wire, the majority of both professional and amateur equipment can work with wire from 0.6 to 1 mm. Also emit a semi-automatic welding machine without gas. This is a very convenient option, due to the price of argon.
Feeding mechanisms can be equipped with one or two pairs of rollers.
Single-pair mechanisms are the most popular. They are used with burners, the sleeve of which has a length of up to 3.25 m.
Each semiautomatic device is equipped with adjustable wire feed speed. There are both step adjustments and smooth. Some models supply wire depending on voltage.
The best models
The best welding semiautomatic device is very difficult to recommend. This is a group of equipment where a universal model for everything simply does not exist. However, you can purchase some affordable devices that are suitable for beginners and professionals. So, both those and others praise the models of Aurora. The brand offers a wide range of various semi-automatic devices.