What Are the Different Types of Welding: Which Is the Best?
When someone thinks about buying a quality welding machine, they may not even know what a variety of models and their performance on the market.
This review will show the types of professional welding machines by current sources and welding modes, which will facilitate the selection of products that will best meet future challenges.
The difference between welding machines depends on
Types of welding machines are depending on the type-of welding
- Devices for manual arc-welding MMA
- MIG/MAG Semi-automatic welding Machines
- TIG Argon Arc Welding Machines
- Universal welding machines
- Spot welding machines
- Plasma welding machines
- Gas Welding machine
To understand what types of welding machines there are, it is worth knowing that the equipment is divided into types of current sources and methods-of welding.
The voltage from the mains of 220 V and 6-32 A is not suitable for performing the welding process, so it needs to be converted.
For this purpose, the following options have been developed.
This is equipment that consumes alternating current from the mains at a frequency of 50 Hz and changes its fluctuations to 100 kHz.
In addition, the voltage is rectified-twice.
In the end, portable welding machine is carried out at a direct current of 30-300 A with a voltage of 50-80 V, which contributes to smooth seams, deep penetration, and less metal splashing.
- To implement the process in the inverter circuit, there are:
- step-down transformer;
- rectifier unit (diode bridges);
- payment with keys;
- the second transformer.
From the device comes two cables, one of which can connect to the product, and the second to the electrode-holder.
The advantages of the inverter are compact dimensions relative to other sources of welding current, light weight of 3-6 kg and quiet operation (pleasant rustle of the electric arc).
The inverters themselves will divide the type of transistors-used in them.
Welding machines of this type are usually cheaper due to the use of simpler Mosfet inverters.
Transistors will develop about 50 years ago.
They are reliable and convert current well for welding ferrous metals.
But they weigh-more than their counterparts.
Even for the normal operation of the inverter, there should be about 20 such transistors in the electronic-circuit (for models with 180 A).
Such types of portable welding machine have protection against overheating, triggered after reaching 60 degrees, so the models are characterized by a low PV of 30-40%.
The loose layout and large details make it easier for the master to access during repairs.
This is a more modern generation of transistors, which is installed in expensive welding-machines.
The weight of the IGBT is less than its analogues and requires up to 10 units in inverters with a power of 180 A.
All this contributes to even smaller dimensions of the welding equipment and weight reduction.
Overheating of the IGBT transistors is triggered after 90 degrees, extending the total time of use of the device.
On the one hand, there are fewer parts in such a welding machine scheme, but on the other hand, they are very small and it is more difficult to replace-something.
An inverter with IGBT transistors.
Among other types of welding machines for manual welding, rectifiers are distinguished, which are relatively cheap and can create high-quality seams.
They consume 220 V current from the mains and lower it through a transformer to 40-80 V, and increase the power to 200-400 A, depending on the power-of the model.
Next, the voltage passes through the diode-block and is rectified.
The design has elements of start – up and protection.
Welding is carried out by direct-current.
The equipment is reliable-and-durable.
There are versions for domestic and industrial-use.
Suitable for welding ferrous and non-ferrous metals, cast-iron.
The main disadvantages are the large weight and large-dimensions. When they are cooked, the rest of the network is very “drained”, and other devices may not work correctly.
The cheapest type of welding machines is transformers.
They consist-of two windings: primary and secondary.
The devices operate on the principle of magnetic induction.
The distance between the windings helps to increase or decrease the current-strength.
Welding can carry out at alternating voltage.
The devices are suitable for joining ferrous-metals.
They are simple and reliable.
Among the disadvantages of this type of equipment are a large weight, a strong hum, high metal splashing and large dimensions.
The welding transformer.
Types of welding machines depending on the type-of welding.
Having considered what welding machines are by the type of power source, we will move on to their varieties by welding-modes.
Devices for manual arc-welding MMA
Such types of welding machines can build on the basis of inverters, transformers, or rectifiers.
The welder wields a holder on which the melting electrode can fix.
metal rod closes the arc on the product and serves as an additive material.
The outer coating, when melted, creates a gas cloud to protect the weld-pool from the external environment.
Machine for manual arc welding – MMA.
This type of welding can be used to connect ferrous metals.
If you install the electrodes with a stainless rod, you will be able to weld alloy-steel.
But the speed of work is slow, you need enough experience to get a high-quality connection, you constantly have to control the length of the arc, as the electrode decreases.
MIG/MAG Semi-automatic welding Machines
MIG/MAG welding can call semi-automatic since the seam is carried out using a burner, but the wire inside can feed from a special-mechanism from the coil.
The principle of operation is similar to the MMA, only instead of the holder, a compact burner will provide.
The metal is connected by an electric-arc (the mass cable is connected to the product, and the “plus” remains on the wire).
Application. Thanks to the continuous feed of the additive, you can create long, neat seams.
There is no slag in the weld pool, so it is better-for the welder to control it.
Protection from the external environment can provide the gas supplied from the cylinder through the nozzle of the burner.
This type of welding is fast and allows you to connect metal with a thickness of 0.6 to 20.0 mm.
Depending on the type of wire to install, you can weld black metal, stainless steel, and aluminum.
But you need to carry a balloon behind you.
Even in the wind and working on the street, the welding bath becomes defenseless (the supplied gas is blown away).
TIG Argon Arc Welding Machines
TIG welding can perform on inverters.
Here, too, there is an electric arc, but it burns between the product and the non-consumable tungsten electrode.
The latter is 1.6-3.2 mm in diameter and will be sharp in the form of a sharp cone.
This allows you to create narrow-seams.
The joints can make both at the expense of only the fused edges, and with the help of an additional additive supply the free hand of the welder.
The welding bath can protect against the argon blown from the burner nozzle.
Application. When working on direct current, you can weld ferrous metals and stainless steel.
There are types of welding machines with AC/DC function, designed for welding aluminum.
With this equipment, you will be able to cook very carefully and economically, but the speed of the method is significantly inferior to the semi-automatic
Universal welding machines
Universal models of welding machines combine several-welding modes at once.
Here are the existing options:
MMA+MIG. The model is capable of cooking with coated electrodes and wire fed from the drum.
In the first case, it is practical for cutting with electric welding, and in the second for mass production of sheet metal-parts or body repair.
MIG+TIG. Semi-automatic with the possibility of attaching an argon burner.
Allows you to quickly apply seams on stainless steel and black metal using the MIG mode, as well as connect aluminum by switching to TIG.
MMA+TIG. Inverter for welding with conventional electrodes and tungsten-rods.
It is practical when alternating welding of ferrous and non-ferrous metals where high speed can not require.
3 in 1. The most versatile machines that can perform welding in MMA, TIG and MIG modes.
For this purpose, there are several sockets on the front panel for connecting the corresponding burners.
Such equipment will purchase for the most versatile tasks
Spot welding machines
Spot welding machines are available in the form of models with pliers for double-sided welding or with a gun and a reverse hammer for single-sided welding.
The first ones can use for the assembly of thin-sheet structures (boxes, doors, gates, wickets)
The latter can use in body repairs when it is necessary to weld to the plane without access to the reverse side.
There are hand-held portable models with a weight of up to 16 kg and stationary contact welding machines.
The thickness of the metal to weld varies from 3 to 9 mm
Plasma welding machines
These types of devices use an electric arc burning in the nozzle between the cathode and the anode.
Compressed air from the compressor can pass through it, which forms a plasma.
Closing the mass on the product allows you to transfer the arc and make it not a duty arc, but a cutting arc.
If you use filler wire, this method is suitable for welding-parts.
Gas Welding machine
The apparatus here refers to an acetylene generator that produces gas when the carbide interacts with water.
Additionally, a cylinder with oxygen can connect, which supports goring and promotes the development of the flame temperature up to 3000 degrees.
But recently, more often than not, they use not apparatuses, but just two cylinders (acetylene oxygen or propane oxygen).
Then for welding it remains only to purchase a burner and two hoses.
The flame heats up the metal edges, and the filler wire fills the weld pool and increases the seam height.
Application. This method is suitable for welding pipes and containers with a wall thickness of up to 4 mm.
Gas welding does not require electricity and can carry out in the field, but the stall rate is very low, and the probability of deformation of the product-from heating is high.
Understanding the difference in the types of welding machines for the current source and the method of welding, you can choose the equipment for specific tasks, whether it is welding parts in the garage, body repair or serial production of products in the workshop.
I’m Sahadat Hossain. I am working as Assistant Professor at Joynagor Technical and BM College. Besides, I have one welding workshop business from 2013. And in 2018 I started blogging about welding accessories. I want to share my experience with using welding accessories. In this blog, all content is written by me.