When selecting a welding machine, it is necessary to understand its power, the corresponding consumables and the operating cycle. A large role is played by the required input power and the type of voltage received. From the principle of the device, whether it is a transformer, semi-automatic or inverter, the quality of the welded joint and the ability to work with different thicknesses of metal depends.
- The best welding machine manufacturers
- The principle of operation and the welding device device
- Types of
- welding machines The parameters of the
- welding machine selection Which welding machine to choose
- How much does the
welding machine cost? The best welding machine manufacturers - which company to choose
If in the home timefrom the time you need a welding machine, but there is no time to delve into all the differences and features, then you can choose quality products from proven manufacturers from the backka below:
Any of these devices will cope with tasks in a private house and yard. But if it is planned to engage in welding at the semi-professional level or in general with full employment, then the capabilities of specific models play a big role in certain production conditions. Therefore it is important to familiarize yourself with the detailed review of the widely used welding machines, which will help to find "your own".
Principle of operation and welding device arrangement
The welding equipment has many varieties, but most models combine the general operating principle, which consists in heating and melting the electric current of the edges of metal and filler material, and creating a single crystal lattice in the overhead seam.
To do this, connect the cable to the parts to be welded, indicated by "-".In the burner or holder, there is a wire with the opposite value of "+".Closing the contacts leads to the formation of an electric arc, whose temperature reaches 5000 degrees. This allows to smelt most kinds of metals.
To fully form the seam use consumables. These are coated electrodes or a welding wire. Melting together with the base material, these became mixed, which gives strength and volume to the applied seam. Due to this, the connection is difficult to break, tear or bend.
When the metal becomes liquid, its molecules can interact with the surrounding air, which leads to the release of carbon and the formation of pores in the seam structure. Such a connection is not capable of hermetically retaining water or gas pressure;Poor performance in his tear and refraction.
To prevent a chemical reaction, use a protective medium in the form of a gas cloud. It is formed due to a special coating of coated electrodes, which creates an impenetrable cloud layer, which prevents the penetration of the atmosphere into the zone of the weld pool. In the case of a semi-automatic machine, where the wire is fed uncoated, this role is performed by a separate gas from the cylinder( carbon dioxide or mixture with argon).
The very process of creating a stable electric arc safe for holding in the hands of a welder is possible due to a change in the characteristics of the welding current occurring inside the apparatus.
Welding machine consists of the following elements:
- transformer with two windings;
- diode bridge;
- throttle with capacitors;
- control unit;
- working elements( cable, holder).
The principle of operation is the passage of electricity through several stages. The input voltage is applied to the primary winding. Due to the effect of electromagnetic induction, the current( ampere) increases by several hundred times, and the volts drop to a safe value.
In the case of a conventional welding transformer, you can connect the parts already at this stage. Inverters and semiautomatic devices, the modified current from the secondary coil undergoes additional frequency increase transformations.
Types of welding machines
Despite the functioning of the welding equipment from the electrical network, there are differences in the internal device and work technique, which affects the quality of the seam and the applicability of the equipment under certain conditions.
Represent the cheapest segment of the market for such products. They have a very simple device and light weight( household versions).Industrial models are characterized by three-dimensional bodies and a decent mass. Suitable for welding carbon steel in all spatial positions.
It is better to use for simple metal structures, where the seams will not be subjected to increased load. With the help of a transformer, you can weld doors, gates, water tank.
- reasonable price;
- simple operation;
- easy repair;
- possibility of power supply from the household network;
- current regulation.
- increased noise from work;
- poorly alloyed steel and cast iron;
- is an uncomfortable lever changing the amperage.
This is an advanced version of transformers with additional elements in the composition. In addition to the two windings that play a key role in reducing the voltage( V) and increasing the current( A), the inverters have a diode bridge that rectifies the alternating current to a constant without oscillation.
Then it goes down and goes to the filter from the capacitors and throttle to re-convert to variable, but with an already increased frequency of tens of times. This allows you to get smoother and more durable seams.
Inverters are good at welding not only sheet iron( fence, gate, tank), but also perfectly suited for the creation of water and heating. Due to the high frequency, they can weld alloy steel and cast iron. A small mass allows you to hang it on your shoulder by the belt and cook at a height.
- very light;
- seams are smoother and more durable;
- high hermetic performance in joints;
- powered by household power;
- wide range of settings;
- has many auxiliary functions for novice welders.
- are more expensive than transformers;
- has more elements in the circuitry that can fail;
- expensive repair;
- , some models support the work not all electrode diameters.
The third category of welding machines combines all the elements from the previous two: in semiautomatic machines there is both a transformer and a rectifying unit. But instead of using coated electrodes, wire feeding from the drum to the coil is used.
This filler material can be fed continuously, allowing a long lead without stopping, which is convenient for long structures( fuel tanks, water filters, continuous welding of metal sheets).
The feed is started by pressing the button on the burner, along with the protective gas is sent to another channel in the nozzle. The rotation of the drum and the delivery of the wire is due to the pinch roller mechanism and the cable duct.
If you change the filler material to a stainless wire, the device is suitable not only for carbon steel. With an additive diameter of 0.8 mm, you can quickly weld a thin metal on the car bodies.
- beautiful smooth seams;
- ability to continuously weld;
- high performance;
- no slag on the surface of the interfering view during welding;
- fast post-treatment of joints;
- the ability to weld very thin sides.
- large dimensions of the device;
- require a gas cylinder and a hose;
- wire on reels costs more than electrodes.
- See also: rating of the best welding semi-automatic machines
Parameters of the
welding machine selection When choosing welding equipment, it is necessary to take into account the forthcoming types of work and conditions on the spot. Knowing the basic parameters and their effect on the result, you can make a competent choice.
To operate the welding machine, it must be connected to the network. There are models with 220 and 380V.Three-phase equipment can not be connected to a household outlet and requires a special connector and cables of large cross-section. Therefore, for welding at home( dacha, garage, apartment) will require a model 220V.
Another thing to consider is the range of current consumption for normal operation. The parameters specified in the documentation 220-230V mean that the equipment can work well with a stable voltage in the network.
If there are frequent jumps in the big side, the device can burn( without the protection installed).With a current drop in the network, the machine will cook poorly( frequent defects in the form of impurities and sticking of the electrode to the surface).In this case, devices with an extended input current range of 140-250V will be needed.
In industrial use, most shields are equipped with three phases, which allows you to connect powerful devices and weld steel 10-30 mm. But for this they must necessarily be grounded by a separate line to the circuit, so that the breakdown of the current does not lead to the death of the worker. In household versions, grounding is part of the structure of the outlet and the plug of the device.
Welding current range
This is a very important parameter on which the ability of the machine to weld metal of a certain thickness depends. It is measured in amperes and is denoted by the letter A. The indicator has two values - the minimum and maximum, and both are important for different types of work.
To weld thick elements( channel, corner, rail), high values of 300-500 A are needed. This will allow not only to apply a seam on top, but also to deeply penetrate the product deep.
In the opposite case, when it is required to work with a thin iron( welding sheets 0.8-1.0 mm to the fence, making containers from tin), the minimum values of the current are important. Apparatus with 20-30 A is useful here. If the threshold is 60-80 A, welding will leave holes and additional resistance will be required to reduce the current.
The form of current regulation is still important here. If the body has a toggle switch with values of 30, 50, 70, 90, 120 A, this will only allow the force to be set approximately. It may turn out that 90 A is not enough for good penetration, and 110 A is already a lot. Smooth adjustment with a digital display and a change in unit gives more precise settings.
It is not difficult for a specialist to look at the thickness of a metal to determine the required current by eye, so an additional parameter is the diameter of the welding electrode that the equipment supports.
To cook thin car bodies it is best to buy a wire for a semi-automatic device of 0.8 mm or coated electrodes of 1.6-2 mm. For welding pipes is best 3 mm, and in the case of manufacturing gates and fences, it is worth buying a device with an electrode diameter of 4-5 mm.
This is not the mains voltage for the supply, but the current figure at the time the equipment is on, but the arc is not lit. This parameter indicates how easy it will be to ignite the electrode.
Values of 35-60 V should only be selected by experienced welders, since a trained hand and the ability to withstand a gap between the end of the electrode and the metal surface of 3-5 mm is necessary.
Novice welders should look for models with idling speed in 70-90 V, which will allow not to knock for a long time at the place of docking, but immediately ignite the arc and start welding.
When the contact is set, the voltage is automatically lowered to 12 V to protect the worker from touching the parts to be welded.
This is an indicator of the temporary use of equipment at the maximum welding mode. For example, a value of 60% indicates that out of ten minutes of work at the highest ampere the device will be able to cook for six minutes, and four need to cool down.
If you plan to use a device for welding doors, fences, heating, where there is a lot of preparatory work as the business progresses, the device will have time to rest and a cycle of 60% is enough. And not each of these processes requires welding at the maximum power mode.
In case of more professional activities with daily work( making safes, welding machines) or working on a volumetric structure( large water tank), where there are long straight seams and you can work for a long time, it is better to purchase models with a cycle index of 80-100%.The latter are generally designed for continuous operation during the entire time of switching on.
Weight of the
This parameter plays a role in frequent shipments. When the main work is done not in the workshop or garage, but every time in a new place( creating heating for people, repair works on the water pipe), then it is very inconvenient to carry a heavy apparatus of 10 kg.
During the day, it may need to be repeatedly moved, which takes additional forces. Therefore, mobile models require light models of 3-5 kg, and for stationary work any device by weight will do.
But the mass of the device is important and for the types of work in the spatial position. If the swara involves creating a connection at a height( supports, balconies, large greenhouses, canopies), then often the welder has to lift equipment with him. Light models of 2-3 kg, worn on the shoulder through the belt, greatly simplify the implementation of such tasks.
Maximum power of the
This parameter is indicated by kW and can vary from 2.5 to 10. It is necessary to take into account these values when working in houses with old wiring and counters that may not be designed for high load and the plugs will constantly knock out. This will not allow welding and the apparatus will be useless.
In this case, devices with a minimum of 2.5-3.5 kW are needed. For industrial conditions or new wiring and modern meters designed for air conditioners, washing machines and irons, you can use more powerful devices.
But this parameter implies the value at the maximum operating mode. For example, a value of 300 A on the scale. If most of the work in the house with the old wiring and the meter is required to be performed at 200 A, then problems should not arise.
Cable length and its cross-section
Usually, 1,5-1,8 m cables for the holder and the mass are supplied with the store devices. This is enough to cook on the desktop in the garage or to connect products on the floor. Such equipment is convenient to collect small tanks and repair work. But it will be inconvenient to make a door or gate because of the size of the structure.
Most doors have a minimum of 1900 mm in length, which will require a rearrangement of the machine to weld all the corners. When working on a greenhouse, which are 2.5 m in height, the welding equipment will have to be raised on an additional rack. Therefore, it is better to buy a cable with a length of 3 m or more.
But with increasing the path for the current, it's worth remembering the wire cross-section. For cables from 3 to 5 meters, you need a cable diameter with a winding of at least 10 mm. This will not lead to overheating and melting of the wire.
Another thing is to increase the power of the welding current on a long cable in order to overcome the increased resistance from the cross-section, therefore, the apparatus, which is planned to work around large products or at an altitude, should have a stock of this value.
Type of current
Welding machines have several types of stress for suturing.
Transformers are alternating with alternating current, which is suitable for simple designs without increased loads( greenhouse, doors, fence).
The inverters operate using alternating current, but high frequency, which makes them practical for welding pipes and tanks.
Direct current devices give greater freedom in the types of metals to be welded and work well with stainless steels( heated towel rails, tanks, bumpers of off-road vehicles).This value is indicated in the characteristics of the device by a straight line or a wavy line, which means a constant or alternating voltage.
Additional parameters for
1. The "afterburning" technology will be convenient for novice welders, since it prevents the electrode from sticking when the end of the electrode approaches the product unsuccessfully. When the hand is not trained to hold a gap of 3-5 mm, the end of the consumable often sticks, which spoils the seam and slows down the whole process. Forcing allows the device to independently increase the current by 1-2 seconds to prevent sticking and further to conduct welding in the exposed mode.
2. The "hot start" function helps to easily initiate an arc. To do this, tap the end of the electrode with the beginning of the welded parts or an additional black plate. The repelling of the coating from blows complicates combustion and reduces the safety of the weld pool. At "hot start", an increased voltage is applied to the electrode at the time of ignition, which makes it easier to ignite the arc.
3. Overheating protection will automatically shut off the device and signal it with a burning light bulb, which will not allow the transformer or diode bridge to burn. This helps to prevent unscheduled repair of equipment, when he was very keen on work, and does not need to periodically check the temperature of the device with his hands.
Which welding machine to choose
1. For welding pipes for heating and water it is desirable to have an inverter with a range of 20-200 A, cables 1.8 m, power 140-250 V, weight 3 kg and cycle 60%.
2. In order to repair cars where welding on a thick frame and a thin body is necessary, the semi-automatic with the possibility of setting up a wire of 0.8-1.2 mm, 20-300 A, a cable channel in 3 m, and 180-250 V. The cyclicity will suit 80-100%.The mass of the device can be 6 or more kg, but this is not important because the body is mounted on a trolley with protective gas and moving on wheels. For large enterprises, a three-phase 380 V model makes sense.
3. A simple transformer 40-250 A, with a cable of 2 m, and a cyclicity of 60% is sufficient for welding doors, fences and gates. Power depends on the local network and can be 220-230 V. If the meter in the house is old, it is better to find not a powerful model in 3.5-4 kW.
4. For work at height( welding of greenhouses, poles, awnings, balconies) you need a light inverter for 2-3 kg, with a cable of 1.8 meters and belt fastening. The current strength can be 30-180 A, since the profile has a metal wall thickness of not more than 2 mm.
5. Furnace furnaces and various heat exchangers require deep welding due to thick walls. Here you need a powerful inverter for 300-500 A with a cyclicity of 80-100% and 7.5 kW.It should support the work of electrodes by 5-6 mm in diameter. Three-phase washing is possible.
How much does the welding machine
1. For pipes it is worth to buy an inverter for 5000-12000 rub. Here everything depends on the availability of additional functions.
2. Semiautomatic machines for repairing cars will cost 16500-160000, where the country of manufacture, capacity and various control units( electronic or mechanical) plays an important role.
3. To make doors and gates or repair the fence, a transformer worth 3700-4500 rub.
4. For easy operation at height, you need a compact inverter with a price from 3500-5000 rub.
5. A powerful inverter model for thick steel for boiler steel will cost 17,000-40000 rubles.