Welding is the most widely practiced way of joining metals together because of the efficiency and economy of the process. It has been estimated that about 50% of the Gross National Product of the United States arises from the activities that are, in some form or another, related, perhaps remotely, to welding. As an example, farming may appear to have nothing to do with welding, but the equipment the farmer uses to grow and harvest crops will have used welding in their manufacturing process.
Until the advent of the 20th century, welding was confined to blacksmith shops where two pieces of metal were heated to very high temperatures in a forge and then hammered together until the joining occurred. This is what is called forge welding. With the introduction of electricity into industrial processes, welding become both easier and quicker, and also more economical.
There are four types of welding techniques commonly used
• Arc Welding – This is the most basic welding technique where the parts to be joined together are brought into contact with strong electrical current and heated. The molten parts are then joined together to form a weld. This is the low technology end of welding in its cheapest and least sophisticated form.
• Gas Welding – This is generally used for repair work, particularly in the case of hollow items like pipes and tubes. Hot gas is forced onto the surfaces to be welded. This procedure requires the parts to be subjected to less heat and is suitable for material that may be damaged due to exposure to high temperature. It is for this reason that it is used in the jewelry industry which has to work with soft metal with low melting points.
• Resistance Welding – This welding technique requires that an additional sheet of metal is used to cover the pieces that are to be welded together. This gives great strength to a weld, but the process requires expensive equipment as well as the use of additional material to encase the weld which makes it expensive and not suitable applications.
• Laser Welding – This is the most modern technology available today. High intensity lasers can be tightly focused and produce controllable heat on the surfaces to be welded very quickly. This is perfect for material that can be damaged by prolonged exposure to extreme heat. Laser welding is very accurate and can be used to produce even the smallest of welds. However, because of the high capital cost involved in buying this equipment, the cost of welding is also high.
Although the perception of welding is that of a simple process of heating and joining, it is a high technology industry with huge amounts being spent on research and development to look for stronger, more accurate and cheaper methods. The welding process plays a big role in metallurgy with a constant effort underway to find newer and more weld friendly ways. Look for a certified welding company for all your fabrication needs.