If you are an experienced welder, then you are unlikely to be interested in the question: which welding machine to choose? But for beginners and non-professionals this question will always be relevant. In order to make the right choice, you can consult with an experienced welder.
The scheme of welding consumable electrodes on alternating current.
In the construction market there is a wide choice of the specified equipment, therefore it is quite difficult to buy the welding machine that will be optimal in your conditions. To make the right choice of welding machine, you must first find out what types of this equipment exist and what are their main characteristics.
If you decide which welding machine is better to buy, then you need to know that there is equipment for manual or mechanical welding of an installation that works automatically. In this case, ordinary or non-consumable electrodes can be used, there are equipment of transformer, generator and inverter types, for ultrasonic, cold welding, as well as for performing resistance spot welding. In order for you to make the right choice of welding machine, you must first decide for what work and for how long you will use this equipment.
Transformer devices of alternating and direct current
Classification of arc welding methods.
In this case, equipment of the transformer type is used, during operation with which melting electrodes are used. Devices that operate on alternating current, have a simple design (therefore they are reliable). To work with such equipment, electrodes with a rutile or calcium fluoride sheath are required, usually operating at a voltage of 220 V.
The maximum size of an electrode that can be used depends on the maximum value of the current, its adjustment is carried out smoothly. If we talk about the types of electrode coatings, then rutile electrodes require less current than those with a calcium fluoride coating.
Devices operating in direct current, have a greater number of parts, respectively, their design is more complicated. But in them, as in the previous case, a melting electrode is used as a working tool. They have a more complex structure and, consequently, a higher cost.
The design of the welding inverter.
Their main difference from the devices of the previous type is that the output is a direct current through the use of a rectifier. It can be diode or thyristor.
This feature allows you to get a more stable arc, however, there is a significant loss of power. Such devices can be used for welding not only with ferrous, but also with non-ferrous metals. Just need to find the right electrodes. They are most often used by professional welders, for beginners and lovers it is better to choose another option.Back to table of contents
Semiautomatic machines operating in inert or active gas, and welding inverters
Semi-automatic welding machines are universal: they are used both in everyday life and when carrying out car repairs. These devices are high-performance, reliable, convenient to work with them. Their main disadvantage is the high cost; therefore, it is irrational and unprofitable to acquire them only for periodic use in everyday life.
In addition to the fact that their design includes a transformer and a rectifier, there is also a gearbox, a sleeve, a wire feed mechanism, which greatly complicates the design of the welding machine.
The wire used for work usually has a diameter of 1.2 -1.6 mm, it all depends on the parameters of the materials that you will connect. It can work with gas supply, and maybe without it. In this case it is necessary to use flux wire. To work with different metals it is necessary to select different gases. For example, carbon dioxide is used to work with iron, and argon is used to work with aluminum.
Recently, welding inverters have become very popular. This is easy to explain, as they are small, light and have a high frequency of voltage. Despite the fact that their cost is high, if you want to have a compact and high-performance equipment, you should choose the inverter.
When making a choice, you must remember that all welding machines, regardless of their type, are divided into categories:
- for household use;
- semi-professional equipment;
- professional appliances.
According to external signs, it is difficult for an inexperienced user to distinguish the type of this device, it all depends on the current strength.
For a household appliance, it is not more than 200 A, semi-professional appliances have a current strength of up to 300 A, and professional appliances are greater than the specified value.Back to table of contents
How to choose equipment?
Once you have decided on what are the main types of welding equipment, you can proceed to his choice. You need to clearly define what materials you will cook and how much you are willing to spend.
For occasional use in everyday life it is not worth buying too expensive equipment. When buying, you need to pay attention to such an indicator as the time of continuous work. It can be found in the technical documentation (this is PV).
If PV35% 160 A is indicated, this means that with such a setting with a current of 160 A, you can work 3.5 minutes, and then 6.5 minutes to rest. Only after that it can be used again for the same period of time. If for household appliances, PV is usually within 20%, then for a professional it should be at least 60%
If you need a welding machine for the house and you are limited in resources, you can purchase AC equipment for manual arc welding. With it, you can do all the homework. If you have enough money, it is better to buy an inverter. In this case, the quality of the seam will be better, and such equipment, due to its low weight and small size, is very mobile and convenient.
When choosing a welding machine can not be unambiguously tell which one is better. It all depends on what criteria of reliability, performance and cost you present to this equipment. In each case, it is necessary to approach decision making individually, taking into account your needs.