Arc welding

Contents-

• Introduction
• advantages
• Disadvantages
• Types of arc weldings

Introduction

Arc welding is one of the most popular types of welding methods. An electric arc is created between metal and an electrode, forming a puddle where additional welding filler material can be added.

Advantages-

There are a number of advantages to using arc welding compared with many other formats:

• Cost – equipment for arc welding is well-priced and affordable, and the process often requires less equipment in the first place because of the lack of gas
• Portability – these materials are very easy to transport
• Works on dirty metal
• Shielding gas isn’t necessary – processes can be completed during wind or rain, and spatter isn’t a major concern

Disadvantages-

There are a few reasons why some people look to other options beyond arc welding for certain kinds of projects. These downsides can include:

• Lower efficiency – more waste is generally produced during arc welding than many other types, which can increase project costs in some cases
• High skill level – operators of arc welding projects need a high level of skill and training, and not all professionals have this
• Thin materials – it can be tough to use arc welding on certain thin metals

The Different Types of Arc Welding

• Arc welding. Arc welding is one of the most common kinds of welding. ...
• Flux-cored arc welding (FCAW) Flux-cored arc welding uses tubular electrodes that are filled with flux
• Gas metal arc welding (GMAW
• Gas tungsten arc welding (GTAW)
• Plasma arc welding (PAW)
• Shielded metal arc welding (SMAW)
• Submerged arc welding (SAW)

Flux-cored arc welding (FCAW)-

Flux-cored arc welding (FCAW or FCA) is a semi-automatic or automatic arc welding process. FCA requires a continuously-fed consumable tubular electrode containing a flux and a constant-voltage or, less commonly, a constant-current welding power supply.

• DCEP (direct current, electrode positive) is commonly employed in FCAW.
• Shielding is obtained by a flux which is contained inside an electrode.
• it is evolved from the MIG welding process to improve arc action, metal transfer etc

Gas metal arc welding (GMAW)-

• Gas metal arc welding (GMAW) is a high-speed, economical process that is sometimes referred to as metal inert gas (MIG) welding.
• This process is versatile, quick, economical and welding productivity is double that of the Submerged-arc Welding process
• The shielding is provided by an external gas, usually containing one of a mixture of Helium, Argon, carbon-di-oxide.
• joins metals together by heating them with an electric arc that is established between a consumable electrode (wire) and the workpiece.
• To protect the molten metal from reacting with constituents of the atmosphere.

Gas tungsten arc welding (GTAW)-

• It uses a non-consumable tungsten electrode to produce the weld also known as TIG weldings.
• It works on the principle of melting and joining of metal.
• The gas is argon, helium, or a mixture of those two as protecting gas of melted metals
• In tungsten inert gas welding, filler rod may or may not be used or if used, it continuously melted by the arc and fed into the weld pool.
  
• Tungsten Inert Gas Welding produces high-quality welds.
• No slag is produced.
• TIG Welding can be done in any position.

Submerged arc welding (MAW)-

• Submerged Arc Welding, is done under the blanket of grannular Flux.
• Extremely high welding currents can be used for submerged arc welding.
• A continuous consumable wire electrode is fed from a coil through the contact tube which is connected to one terminal of the power source.
• For higher diameter electrodes constant current DC source is used (dia range 1mm-5mm)
• The arc and the weld zone are completely covered under a blanket of granular, fusible flux which melts and provides protection to the weld pool from the atmospheric gases.
• slower travel speed reduces the tendency to porosity and slag inclusion.
• Multiple arcs are used to increase deposition rates 

Shielded arc welding (SAW)-

• Shielded Metal Arc Welding, is one of the world’s most popular welding processes.
• SMAW welding is a process which uses a consumable electrode which is covered with flux.
• Alternating current (AC) or direct current (DC) used to form an arc between the electrode and the metal.
• gas protects the weld from certain atmospheric gasses which can affect the weld’s quality.
• his process also forms a layer of slag which has to be chipped off – which does make it less time efficient than many other types of welding.
• SMAW welding is used for heavy-duty, industrial steel and iron jobs, but it can be used to weld aluminum, and other metals as well.