A welding machine is an equipment that joins 2 or more metals by heat. There are many different welding techniques and many different types of welding machines to do this.
However, the most popular type of welding machine available in the market today are arc welding machines.
How do Arc Welding Machines Work
Arc welding, just like its name suggests, uses an electric arc to produce heat of high intensity needed to melt metals. The arc is produced between an electrode in the form of a stick or wire and the metal piece that is being worked upon. The electrode can be manually or mechanically guided along the joint of the metal.
There are many different types of arc welding machines and arch welding processes.
Some examples of arc welding processes include
- MMA Welding/Stick Welding
MMA Welding which refers to manual metal arc welding is often known as flux shielded arc welding or stick welding.
In MMA Welding, an electric arc will burn between a coated electrode and the metal piece you work on. This is done with an electric current in the form of a direct current or an alternating current from a welding power supply passing through the coated electrodes.
The heat from the electric arc melts and mixes the metal piece and the electrode, which forms a solid mass upon cooling.
As such, the central metal electrode, also sometimes known as the core wire, serves as a consumable and provides the filler metal for the weld.
MMA welding can be used to the join the following:
- Most Steels (Including Stainless Steels, High Strength Carbon Steels..)
- Cast Irons
- Non-ferrous Materials
- MIG Welding (Metal Inert Gas Welding)
MIG Welding, also known as metal inert gas welding, is a welding process in which an electric arc forms between the metal(s) being worked upon and a consumable wire electrode. The consumable wire electrode heats the metal(s) being word upon, causing them to melt and join.
Together with the wire electrode, a shielding gas also feeds through the welding gun. This shielding gas, which is a metal inert gas, shields the entire process from contaminants in the air. To carry out MIG welding, both DC and AC current can be used. MIG Welding is a fast process, however its effectiveness can be reduced in windy situations, where the wind interferes with the shielding metal inert gas!
- TIG Welding (Tungsten Inert Gas Welding)
While both MIG Welding and TIG Welding use an electric arc to produce a weld, unlike MIG welding, TIG Welding uses a non-consumable tungsten electrode to make the weld.
TIG Welding also requires a lot more skill as compared to MIG Welding, which is a very simple and easy process to learn.
TIG Welding Machines are more versatile and can weld a lot of different types of metals as compared to MIG welding. However, TIG welding is a very slow process.
How to choose an Arc Welding Machine for your needs
There are 5 factors that you need to consider when buying or renting an arc welding machine.
There 5 factors include:
- Which material will you be welding?
Different types of welding machines and welding processes are able to weld on different materials. Only TIG welding can weld on lots of different types of metals including Copper and Brass. MIG welding on the other hand, can only weld on certain types of metals.
- What type of welding do you need?
You need to access what you will be using the welding for. The welding process, and welding machine, you would require for heavy duty production welding would very much differ from the welding machine most suitable for occasional repair and maintenance welding.
For example, the Weldman Inverter Welding Machines are built for heavy duty production welding. This is reflected in its power components that are efficiently cooled, so as to deliver high welding currents for long hours at high rated duty cycles (70%).
Also, if you are going to be moving around your welding machine a lot, you might want to look into a small portable welding machine, instead of a large and bulky welding machine that is difficult to move.
When buying a welding machine, other factors to also consider would include the type of electric supply your welding machine will have access to. This is because you may not have access to both single phase and three phase electric supply, in the location you want to use your welding machine.
For advice on the type of welding machine suitable for you based on your welding needs, feel free to contact our friendly welding experts for some advice!
- What welding processes would you be using?
Different welding processes have different advantages and disadvantages. For example, if you require high speed welding, you will probably be looking at MIG Welding. For very high quality welding (E.g. When building leak proof tanks), you will have to use TIG Welding.
But what if you have varying uses, and varying welding processes that you want to use?
Because you can still get multi functional welding machines that cover a full range of welding processes, whether you want MMA welding, MIG welding or even TIG welding.
- How long do you want your machine to last and what’s your budget?
If you want a cheap welding machine, to last just a few years, you could consider looking at manufacturers in China for your procurement needs.
However, many companies are looking for welding machines that are long lasting and durable! Because many a time, paying more at the start for quality and durability, is only going to save you lots of money in the long run especially if you are buying a welding machine for long term use.
For example, some of our clients have been using our locally manufactured Weldman welding machines even after 17-18 years!
One of the reasons why our machines are so durable is because we not only use high quality parts sourced from all over the world in our machines, but also conduct thorough quality checks in each and every stage of our manufacturing process.
Other ways Weldman Welding Machines are durable and suitable for long term use include:
- The Power semiconductor component’s lifespan is enhanced by thoughtful and strategic design of forced air-cooling system.
- The inlet air cools the heat sink fins and powers magnetic components. The power semiconductor components and their live terminals are not in the airflow path and are thus protected from dust and moisture. Hence, the maximum temperature of the heat sink is 70 Degree Celsius.
- How power efficient do you want your machine to be?
Some welding machines may be cheap in terms of the raw cost of the machines themselves, but expensive in terms of the energy consumption.
Its similar to cheap printers, where you can save on costs on the printers themselves, but you end up having to spend so much just for the printer inks.
Pointless, isn’t it?
That is why at Lincoln Machinery we ensure that our Weldman Inverter Welding Machines are highly energy efficient. The energy cost saving can be up to 90% in no load and up to 30% in load condition when compared to conventional machines. Weldman inverter welding machines consume less kVA compared to conventional machines due to high power factor. This leads to lower size supply cables and associated switches, MCBs etc. too.
Substantial fuel saving is achieved when these inverter welding machines are powered by diesel generators. Less fuel usage leads to less emissions and consequently less costs and less environmental pollution as well.
To verify the cost effectiveness achieved by less fuel consumption, we also did some experiments and cost calculations ourselves – and here is what we found!
Input KVA=Square Root 3 x Input Voltage x Input Current from Mains/1000
Power Consumption (kw) = Input KVA x Power Factor
Cost ($) = Power Consumption (kw) x Time (hr) x Cost per kwhr ($)
|Weldman Inverter||DC Rectifier|
|Amps @ Idle||0.25||2.1|
|Amps @ Load||25.42||36.44|
|Idle Time %||60||60|
|Arc time %||40||40|
|Cost/KwHr||$ 0.21||$ 0.21|
|Idle Cost / Day||$ 0.15||$ 1.21|
|Load Cost / Day||$ 11.55||$ 14.92|
|Total Cost / Day||$ 11.70||$ 16.13|
|Total Cost / Yr.||$ 4095.00||$ 5645.50|
|Savings / Yr.||$ 1550.50|
|% Reduction||– 27.5|
Indeed, Weldman Inverter Welding Machines can save you $1550 a year, based on taking a reasonable estimate for the usage time of these welding machines.
Multiply that by 10 years, and that’s more than $15000 in cost savings for you and your company!
- What Suggested Welding Parameters do you have to comply to?
This will mainly depend on your company rules and regulations, and where you are going to carry out your welding process. Some areas may be sensitive to high currents and voltages, where as others may require lower ones.
Many welding machines have strict voltage and current requirements you must adhere to, and you would not be able to make any adjustment to the machine’s operating voltage and current.
At Lincoln Machinery, however, you can customize even your voltage and current specifications of your welding machine to your needs!
Welding Machine Maintenance and Repair
Different welding machines have different maintenance and repair guidelines that one may need to adhere to.
Here are some maintenance guidelines we advice all our clients to stick to.
For trouble free operations, follow the duty cycle of the welding machine (Do not overload). The wire feeder of the machine should also be thoroughly inspected, tested and serviced at least annually. More frequent checking will be required when the equipment is heavily used.
Here are the repair guidelines we offer our clients:
a. Torch moved over work-piece too quickly.
b. Shielding gas incorrect.
? Slow down the torch movement.
? Check and use the correct shielding gas.
|1. Weld deposit stringy and incomplete.|
|2. Weld beadtoo peaky (more height).||
a. Torch moved over work-piece too slowly.
b. Welding voltage too low.
? Increase the torch movement speed.
? Increase the voltage setting for flatter beads.
|3. Arc unstable, excessive spatter while welding.||
a. Torch held too far from the work-piece.
b. Rust, grease or paint on work-piece.
c. Insufficient shielding gas.
d. Incorrect wire speed for the arc voltage.
? Hold the torch closer to the work-piece.
? Clean the work-piece to be free from rust, grease or paint.
? Check gas regulator gauge, regulator setting and operation of the gas valve.
? Adjust the speed for smooth welding.
|4. Frequent arc lengthening.||
a. Contact tip loose or damaged.
b. Welding wire or torch liner worn out or damaged.
c. Worn out feed rolls.
d. Outlet guide or pressure roll adjustment incorrect.
e. Blockage inside the liner or contact tip such as kinks, dust, burs etc.
? Tighten / replace.
? Check and replace.
? Check and replace.
? Adjust pressure roll.
? Check, clean and / or replace if necessary.
|5. Burning holes in the work-piece||
a. Torch moved too slowly or erratically.
b. Welding volts too high.
c. Wire feed speed too high
? Increase and maintain the torch movement speed.
? Decrease the voltage setting.
? Decrease the wire feed speed.
|6. Lack of penetration||
a. Torch moved over work-piece
b. Welding voltage too low.
? Slow down the torch movement.
? Increase the voltage setting.
Dust and other particles inside the machine should be removed by soft brush(Cleaning).
Compressed air blow will cause air pollution and high-pressure air blow will damage the PCB etc. Check for any loose connections or damaged cables.
Wear and tear is inherent particularly in electro-mechanical and moving components. Regular inspection and maintenance of torch, torch accessories like the contact tip, liner and wire feeder parts like drive rolls & pressure rolls should be carried out for trouble free operation. This will reduce the repair costs and improve the performance, reliability and safety of your welding machine.