30-08-2014, 11:29 AM
Welding
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Welding
My senior project will be about welding. The paper will consist of the history, what it is needed for, the different types, and the required knowledge for welding. It will also explain how it is one of the most in demand industry jobs. The product of the paper will be a homemade barbecue pit.
Welding is one of the most in demand jobs of industry jobs. Although welding is considered a relatively new process as practiced today, its origins can be traced back to ancient times. Around 1000 B.C., the Egyptians and others in the Eastern Mediterranean area learned to accomplish forge welding. It was the natural extension of hot forging, which they used to make weapons, tools, and other implements. From these early beginnings up to the middle ages, the blacksmithing trade developed the art of welding by hammering to a high level of maturity.
It was not until the 1800’s that the technological foundations of modern welding were established. It was during this period that two important discoveries were made, both attributed to the English scientist Sir Humphrey Davy. Those were the electric arc and acetylene gas. Davy observed that an electric arc could be struck between two carbon electrodes around 1801. However, not until the mid-1800’s, when the electric generator was invented, did electrical power become available in amounts sufficient to sustain arc welding. It was a Russian, working in a French laboratory was granted a series of patents for the carbon for the carbon arc welding process. One of the patents happened in England in1885 and another in the United States in1887. By the end of the century, carbon arc welding had become a popular commercial process for joining metals.
In 1892, an American named Charles Coffin was awarded an U.S. patent for developing an arc welding process utilizing a metal electrode. The unique feature was that the electrode added filler metal to the weld joint. The idea of coating was to shield the welding process form the atmosphere. That was developed later, with enhancements to the metal arc welding process being made in England and Sweden starting around 1900. Between 1885 and 1900 several forms of resistance welding were developed by E. Thompson. This included spot welding and seam welding, two joining methods widely used today in sheet metalworking.
During the 1890’s, hydrogen and natural gas were mixed with oxygen for welding, but the oxyacetylene flame achieved significantly higher temperatures. Although Davy made the discovery of acetylene gas early in the 19th century, oxyfuel gas welding required the subsequent development of torches for combining acetylene and oxygen around 1900. (Origins of Welding). Gas welding and cutting were perfected during this period as well. The production of oxygen and later the liquefying of air, along with the introduction of a blow pipe or torch on 1887, helped the development of both welding and cutting. Before 1990, hydrogen and coal gas were used with oxygen. However, in about 1900 a torch suitable for use with low-pressure acetylene was developed. (The History of Welding).
Welding is a great occupation. There are many ways to become a welder. Some high schools offer welding classes that prepare students for college or future jobs. A high school diploma preferred, but not required. High school courses in mathematics and physics are recommended. Starting out of high school with only basic welding skills, you are looking at about $13 to $22 an hour. (Welding Salary) Colleges sometimes have available welding courses or on the job training. Certain companies provide on the job training, but most of them require knowing most of the skills already. Once a welder has learned the skill of welding it becomes easy to find a job. The more experience the welder has the better jobs are available. (Jeff Foster) Welders usually make $33,000 to $100,000 a year depending on what type of welder they are. The highest paid welding is underwater welding and welding offshore. They make at least $50.00 an hour.
Welding is one of the most in demand jobs, because of what it is. “Welding is the most economical and efficient way to join metals permanently. It is the only way of joining two or more pieces of metal to make them act as a single piece. Welding isn't necessarily a complicated process. You can learn the basics of several welding meth¬ods in hours. Welding is easy to learn yet hard to master. Professional welders have a mountain of different variables to consider when doing their job. No matter how complicated the job, though, they only need three things to get it done: a welding rig, material to weld and safety equipment (how stuff works). Welding is vital to our economy. It is often said that over 50% of the gross national product of the U.S.A. is related to welding in one way or another.” (Welding Basics). Welding is just about part of everything you see and touch on a daily basis. The metal frame of your car is put together by a welding process, also parts of making airplanes, ships, and most of the manufactured products. That is why welding is one of the most in demand jobs.
There are many different types of welding. “The main types of welding used in industry and by home engineers are commonly referred to as Mig, Arc, and Tig welding. Mig welding is the most widely used and perhaps the most easily mastered type of for industry and home use. This process is mostly suitable for fusing mild steel, stainless-steel, as well as aluminum.” Mig welding is done by wire feed. The wire feed prevents the welder from having to stop. Another benefit to using Mig is it can be done in all positions. “Arc welding is another type of welding that is also known as stick welding. Stick welding is a slang term commonly used for Shielded Metal Arc Welding or “SMAW”. Stick welding is the most basic and common type of welding processes used. It is also the first process learned in any welding school. Stick is the most trouble free of all of the welding processes and is the fundamental basis for all the skills needed to learn how to weld. This is classified as the most basic of all welding types. Arc welding is mostly used for construction, manufacturing, and repairs.” This type is used in factories, welding shops, and schools. Arc welding is also the most common used when underwater welding. (Stick Welding.) “Tig welding is one of the more difficult types. This means it will need more expertise from the welder. TIG Welding is also a slang term commonly used for Gas Tungsten Arc Welding or “GTAW”. TIG welding also goes by the term HeliArc welding. TIG welding is the most difficult of the processes to learn, and is the most versatile when it comes to different metals. This process is slow but when done right it produces the highest quality weld! TIG welding is mostly used for critical weld joints, welding metals other than common steel, and where precise, small welds are needed. (Tig Welding.)Unlike other welding types Tig have to be done with two hands. The welder has to hold the filler material and operate the welder. This is what makes the process so difficult. Flux Cored Arc Welding “FCAW” is nothing more than a different welding wire or electrode for a MIG welder! FCAW wire is a hollow or tubular wire that has a flux inside of it that provides a shielding from the air when it is welding. What this does is help a MIG welder to weld in windy conditions and it increases how much weld can be welded per hour. The powder flux inside also has metal mixed in that increase the weld deposit rate (Flux Cored Arc Welding.)
There are many different needs for welding. Construction and manufacturing companies usual need some welding done. Construction companies build bridges that may require welding. When building a bridge welding is needed to join the steel frame together. Without welding the steel would not hold together. A pipeline also involves welding to join them together to transfer oil and gas across the country. Jobs such as this require a lot of skill in order to weld at different angles and position of the pipe. Many of the products that are manufactured today are mostly by welding.
Welding has many different types of working conditions. The work conditions depend on the job type and the environment. Welders often wear protective clothing, goggles, helmets, and other safety equipment. “Welding gloves are a very important part of safety equipment due to the fact that the electricity produces a large amount of heat.” Long sleeve shirts are also used for heat protection and keep sparks from burning the skin. A welding helmet is required while welding. The helmet is to protect the welder’s eyes from the excessively bright arc. The helmet has a dark tented lens. It also protects their eyes and face from get burned by the sparks created when welding. The proper footwear is necessary when welding to protect the feet and toes from any falling objects. Long pants are also needed to protect the welder from heat as well as sharp objects.
“Many experienced or retired welders start their own independent work. There are many expenses for independent welders.” (Jeff Foster.) Depending on the size and type of welding machine the prices differ. An arc or stick welding machine can be anywhere from $299 to $3000 or higher. Welding rods or electrodes for the machine cost about $25 per box and could come in many different sizes and flux types. Mig welders sell for $200 to about $2000 and up. Wire is also needed for a Mig welder. Cutting torches are used in welding shops to fabricate objects by cutting them out using heat and oxygen. Torches which cost anywhere from $30 to $150. (Welders and Welding Equipment.)