Introduction to Welding.. Welding is one of those construction niches that doesn’t get a lot of attention, but is absolutely critical to the completion of any metal structure. Here is an introduction to the subject.The field of welding is not really a totally modern career born in the Industrial Revolution. Pictures of welders and their ancient tools have been discovered in sealed Egyptian tombs.

Welding is the process of joining metals through the use of heat and pressure. Many people credit developments in the art of welding as enabling many of the technological advances that marked the industrialization of the world.In many cases, welding involves temperatures that are incredibly high. Steel, for example, melts at around 2,800 degrees Fahrenheit.

Welding is a very essential part of just about every modern industry. In the year 2000, a total of over 34.1 billion dollars was spent on welding related costs in American industry alone. If you break this down, it amounts to around $325 per American household.

In 2004, 429,000 professional welders were engaged in welding related work in the United States. They were engaged in a wide variety of different work, but a large percentage of them were working in fields that were extremely vital to the economy and security of the country. The average age of these welding professionals was 54 years old. So, many of these will be reaching retirement age in the next ten years that the United States Department of Labor estimates a shortage of nearly 250,000 welders by 2010.

For the past two decades, the shift in the work force from blue collar to white collar has created a significant shortage in skilled workers. This is especially true of welders. The pendulum will have to shift soon. There will be such a shortage of skilled welders in the coming years as to create a serious industrial crisis. This has only opened up the field to young people looking for a secure and useful trade. Pay scales and benefits of the jobs have risen as a result of the shortage. There are several different forms of welding used in industry today. The common types that use an "arc" to heat the metals to fuse them are Gas Metal Arc Welding (GMAW), Gas Tungsten Arc Welding (GTAW), and Shielded Metal Arc Welding (SMAW). Another type that does not use an arc, but rather electrical resistance and pressure is called Resistance Welding.

The most common method of fusing metals with heat today is arc welding. Arc welding is not a modern discovery per se. It might be said to date all the way back to 1800 and the first carbon electrodes. In 1800, Sir Humprey Davy demonstrated an arc between two carbon electrodes. The sudden surge of electricity that caused the arc created a tremendous amount of heat. It did not take long for people to realize the fact that arcs could be used to fuse metals. Arc welding history might be said to have begun with this remarkable demonstration, but it would be another 90 years before the first arc welding process was patented in the United States. In 1890, in Detroit, Michigan, C.L. Coffin applied for a patent for an arc welding process that used metal electrodes. Prior to this time, welding was done with gas. Gas cutting and welding were widely used in many industrial applications during the entire 19th Century. The gas welding was much slower as the amount of heat was nowhere near what was possible through the arc welding process. World War I brought a tremendous surge in the demand for welding. This demand arrived at roughly the same time as the introduction of arc welding and all over the United States and Europe companies began to produce welding machines and electrodes.

In the years right after the end of the war, The American Welding Society was formed to help establish standards and to advance the craft of welding. During this period, there was a lot of controversy over the use of heavy coated electrodes vs. light coated ones. Other processes were developed during this period as well, 1920 saw the first use of automatic welding using bare wires and electrical current.

During the 1920’s, which could be called the Golden Age of Arc Welding there was a great deal of research into the use of gases to shield the weld areas. The use of oxygen and nitrogen tended to produce porous and brittle welds. Research eventually led to the use of hydrogen as the shielding gas. At the same time tungsten was found to be a better material for electrodes than carbon. It would be the beginning of the modern era of welding that began with the great military buildup during the Second World War. Introduction To Welding.

The 1960’s saw the widespread use of CO2 as the new inert shielding gas in arc welding. Plasma arc welding was invented in 1957. It involved a constricted arc or sometimes the arc was directed through a small orifice to create a plasma arc that created a much higher temperature than tungsten rod welding.

Arc welding has given us a major step up in the manufacture of metal components. So, how exactly does it work?

Arc welding uses an electrical power source that creates an arc between an electrode and a base substance. The arc creates enough sustained high heat to melt the metal at the point of the arc allowing the metals to fuse. Electrodes come in two different types. They are either consumable or non-consumable depending on if the electrode is actually used up in the welding process or is able to be reused. These are just a few facts about arc welding. The welding area is often protected by some type of inert gas. This is called shielding. In the early days of arc welding, the shielding gases were oxygen and nitrogen. These gases led to bad welds. They tended to be brittle and porous and tended to fail. In the middle of the last century, research showed that hydrogen worked much better. Later, carbon dioxide replaced hydrogen as the gas of choice in shielding.

The welding industry is very fond of the use of initials in describing the various welding processes. MIG and TIG welding is a good example. MIG welding means metal inert gas welding and TIG welding is tungsten inert gas welding. Other common expressions are SAW for submerged arc welding and FCAW for flux-cored arc welding. Sometimes, people find themselves unduly intimidated by all of these initials and view learning welding with the same skepticism as learning ancient Greek. The truth is that welding, although a very highly skilled craft, is not that difficult to master. This is an important fact about arc welding because there is a severe shortage of qualified welders and the demand is growing everyday. Almost 80% of American companies that utilize arc welding in their manufacturing process report that have difficulty finding new employees to fill vacancies. It was recently reported that the average age of the professional welder was a very high 54 years. It is easy to see that this rather old work force will be reaching retirement age in high numbers over the next ten years. This has led to the arc welding field being called one of the best kept secrets in the future employment picture.

Because of the use of high voltage electrical currents and extremely high temperatures, arc welding has often been viewed as rather dangerous occupation. The risk from burns and electrical shock was high in the past and the reputation was somewhat deserved. Today, advances in safety regulations and personal safety equipment have reduced the risks greatly. In fact, welding is now considered to be no more dangerous than crafts such as carpentry and plumbing.

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