A welding machine joins metal together by producing heat and is an essential part of all metal processing industries. The welding process temporarily melts two or more metal parts, which are then joined upon cooling, creating a fixed and rigid joint.
A welding machine is used by a trained technician across a range of industries. These include; automotive, aerospace, architectural, agricultural, mining, construction, rail and maintenance. Industry professionals use different welding techniques depending on the desired production specifications and material involved in the project. Two of the most common welding methods used are MIG and TIG welding. Other welding types include; friction, arc, resistance, electron beam and laser.
Stick or arc welding can also be done using a welding machine. This type of welding is the simplest and most cost efficient. It gets its name from the stick-like electrode used to complete the welding process.
During this process, two electrical clamps are positioned to make a circuit. One electrical clamp is attached to the stick electrode. The other clamp is attached to the material that is being worked on. When the end of the metal stick touches the material a short circuit is created, which results in a tremendous amount of heat. This heat causes the base metal and the tip of the rod to melt, fusing them together into a single joint. Stick welding equipment is generally inexpensive and portable.
Welding is extremely dangerous and requires good quality protective equipment to be conducted in a safe manner.
The following specialised equipment should be worn at all times while welding:
Welding machines vary in cost depending on the supported welding type and the features offered by the individual model. Generally, basic stick welding machines are the cheapest ranging from $200 - $700, followed by MIG and TIG machines $400-$1,200. Finally, multi-process machines are the most expensive, costing between $1,500-$70,000.
Operating a welding machine can be extremely dangerous. As a result the Australian Government requires commercial operators to complete a Certificate III in Engineering - Fabrication Trade (MEM30305) and an apprenticeship under the supervision of a qualified welder. Pre-apprenticeship courses are also available to provide the knowledge and skills required for employment as an apprentice.
Multi-process welding machines are designed to do two or more of the following types of welding; MIG, TIG, flux-core arc, wire and plasma cutting. They are generally more expensive than a single-process welder, however, can be cheaper than buying multiple welders. Multi-process welders are ideal for worksites that require a range of different welding types. It is important to note that the gasses and material required to perform each type of welding is different and will require the user to manually change.
The duty cycle is a key component when choosing a welding machine. The duty cycle refers to the percentage of time that the unit can be safely operated at a certain amperage. This cycle is generally measured in a ten minute time frame.
For example, a machine may run with the following duty cycle - 60% duty cycle at 140 amps. This means the machine will run continuously at 140 amps for 6 minutes and then cool down for the remaining 4 minutes. When choosing a machine it is important to note that the duty cycle will change at different ampages and each machine will have its own cycles.
There are a couple of notable differences between metal inert gas (MIG) welding and tungsten inert gas (TIG) welding. MIG welding involves a filler material to join the metal together, while TIG welding does not. MIG is easier to learn and also faster to perform, resulting in shorter lead times and lower production costs. The welds produced by MIG welding require little to no cleaning and finishing.
On the other hand, TIG welds are not only more precise, they also provide stronger and cleaner welds. This type of welding is highly versatile, enabling operators to join far greater types and thicknesses of materials. TIG welders are suitable to be used outdoors as they are not affected by external factors such as wind.
If you are looking to a buy a Welding Machine for sale, suppliers on IndustrySearch include Welding Industries of Australia, Wilson's Industrial Sales, WeldQuip Group, ACL Industrial Technology, The Lincoln Electric Company, Industrial Robotics