An Introduction to ARC Welding…
Arc welding, also known as Stick Welding, MMA (Manual Metal Arc) or SMAW (Shielded Metal Arc Welding). Arc welding is the process of joining metals with the use of electrical current to produce heat. Current passes from the MMA Welding machine through the torch and electrode to the work piece, forming an arc which creates around 6000˚ F or more, melting both the filler rod and parent metal developing a weld pool. The idea is to guide the weld pool flow by a rocking hand movement in the shape of a ‘C’, whilst maintaining a constant momentum along the joining metals. A flux forms around the weld to provide protection from weld contamination and also stabilises the arc. The flux can then be removed with a chipping hammer and/or wire brush.
Electrode application…
Electrodes are available for joining all types of ferrous metals including stainless and cast irons as well as copper and nickel alloys and for some aluminium applications.
Advantages of ARC Welding…
The main advantages of Arc welding are:
- The Equipment is relatively easy to use and inexpensive.
- The equipment is portable and ideal for confined spaces.
- Auxiliary gas shielding is not required.
- Arc welding is suitable for most commonly used metals and alloys.
Disadvantages of ARC welding…
The disadvantages of ARC welding include:
- When arc welding the electrode must be replaced frequently.
- The rate of deposition is lower then continuous electrode process.
- Slag has to be removed from the weld.
Arc Welding Components…
Electrode Holder – A device used to hold an electrode that conducts current through the welding cable.
Earth Clamp – A device to effectively clamp to the work piece to complete a circuit and allow welding to commence.