Basic Electrical Welding Technique

The principle of electric welding

Joining two or more pieces of metal together by melting or burning the search with an electric arc as a source of heat. The use of electricity as a source of light is divided into two:

1. Electric resistance welding
2. Electric arc welding flame


Electric resistance welding is a welding process will be undertaken by an electric current flows through the fields or the surface of the workpiece to be on the dial or the welding. Prisoners in the electric current will arise in the fields of touch and useful heat will cause the surface of the melt grafting. Thus, the pressure exerted between the two materials will cause a blend of work between the two pieces are connected. While electric arc welding is a welding flame that is done by changing the electrical current into heat to melt or melt the surface of the object to be spliced ​​and generate electricity through the flame arc electrodes. The occurrence of an electric current is caused by the voltage difference between the two poles of the work and electrode. This voltage difference is called voltage arc flame.
This voltage large between 20 volt and 40 volt

b. Electrode
Electrodes is an important part in the electric arc welding. During the welding electrodes will expire at on welding. Will affect the types of welding electrodes, so that the selection and type of elektrode be appropriate. Based on the protective film can be divided into two kinds of electrodes and electrode webbed plain.

Webbed electrode consists of the core and the protective or flux. Coating flux coating done with the way in spray, dip or destrus. Her purpose in this flux to the electrode when burning will produce co2 gas welding in order to protect the liquid, an electrical arc of oxygen that can undergo oxidation so that the weld material will affect the nature of the mechanism of the weld metal.
So the membrane electrode has functions such as:

1. Prevent formation of nitric oxides and metal during the welding process takes place.
2. Creating a protective shaft so as to reduce the speed of cooling, with the aim of the welded workpiece does not have brittle or fragile.
3. Provide specific properties of the weld by adding certain substances contained in the membrane.
4. Stabilize the arc and the arc flash drive so easy to control.

Hence the choice of electrode should be appropriate to consider the following.
• Type of weld metal to be in
• Thickness of material to be welded
• mechanical strength that is expected from the welding
• Outstanding welding and
• The seam of the workpiece

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Scope and Definition of Welding

Definition of welding according to the American Welding Society, 1989

Welding is that the method of gold or non gold affiliation created by heating the fabric to be connected to the attachment temperature is carried out: with or while not the employment of pressure (pressure), solely the pressure (pressure), or with or while not employing a filler metal (filler)

Definition of welding according to the British Standards Institution, 1983
Welding is the process of switching between two or more materials in a plastic or liquid state using thermal (heat) or pressure (pressure) or both. Metal filler (filler metal) with a melting temperature equal to the melting point of the parent metal can be used within or without the splicing process.

Historians estimate that the ancient Egyptians began using welding with pressure in the year 5500 BC (to create by hammering sheets of copper piping that edges close to each other). Bendaseni Winterton said that the Egyptians made in the year 3000 BC consists of the base material of copper and gold smelting and beating results. This type of welding, which is called welding wrought (forge welding), is the first human effort in connecting two pieces of metal. Welding example is the famous ancient forging Damascus swords are made with forged iron layers of different nature.

Welding forging has evolved and important to the ancient Romans so that they refer to as a god Vulcan (the god of fire and metalworking) for the state of art. Now the word is used for retreading rubber with sulfur treatment process, but the first word means "hardened". These days welding wrought practically been abandoned and the last made by a blacksmith.

Years 1901-1903 Fouché and Picard developed a welding rod that can be used with acetylene (carbide gas), so since it began the era of welding and cutting oksiasetilen (carbide gas oxygen). Period between 1903 and 1918 was a period of use of welding mainly as a way of improvement, and the most rapid growth occurred during World War I (1914-1918). proven welding technique can be applied mainly to repair the damaged ship. Winterton reported that in 1917 there were 103 enemy ships in the U.S. are broken and the number of workers in welding operations increased from 8000 to 33 000 during the period 1914-1918. After 1919, the use of welding as construction and manufacturing techniques began to evolve with the first electrode alloy (alloy) the copper-tungsten for welding point in 1920. In the period 1930-1950 occurred a considerable increase in the development of welding machines. Sunset flame arc welding process (submerged) the arc flame sealed under a flux powder first used commercially in 1934 and patented in 1935. Now there are more than 50 kinds of welding processes that can be used to connect various metals and alloys.

Welding that we see today is much more complex and highly developed. Advances in welding technology is so rapidly until 1877. Prior to 1877, forging welding and soldering process has been used for 3000 years. The origin of the electrical resistance welding (resistance welding) began around 1877 when Prof. Elihu Thompson began experiments on the reversal of the polarity of the transformer windings, he received his first patent in 1885 and blunt the electrical resistance welding machine (resistance butt welding) was first exhibited at the American Institute Fair in 1887.

In 1889, Coffin was given a patent for welding flame blunt particles (flash-butt welding) welding process is a blunt one that matters. Zerner in 1885 introduced the flame carbon arc welding process (carbon arc welding) using two carbon electrodes, and NG Slavinoff in 1888 in Russia was the first to use the flame of metal arc process using bare electrode (without coating). Coffin also working independently investigate the flame of metal arc process and received a patent in the United States in 1892. In 1889, A.P. Strohmeyer introduced the concept of a coated metal electrode to eliminate the many problems that arise in the use of bare electrodes. Thomas Fletcher in 1887 wearing inflatable tube of hydrogen and oxygen are burned, and show that it can cut or melt the metal. At this present time welding technique has been used widely utilized in various fields. Wide use of welding technology due to buildings and machinery are made by means of welding techniques are becoming cheaper.

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