Welding

From GAWDAwiki

Welding refers to the the process of joining two or more metals together. These metals are joined by melting and then fusing either the base metals or applied filler metals. This is done using pinpointed localized heat.^[1]

History

While welding as it is known today did not come about until the 19th century, primitive welding processes have been in existence for thousands of years. Metal tools and weapons have been discovered dating back to 1000 B.C.E. It was during the Bronze Age that humans first learned to fuse two metals together using heat. The Iron Age brought about increased use of fusing procedures. In the Middle Ages, blacksmithing was developed, which joined two metals through the use of fire and hammering.

It was Edmund Davy's discovery of acetylene in 1836 that is commonly attributed as the beginning of modern welding.^[2] Shortly after, it was discovered that acetylene combusted with oxygen produced a flame whose temperature was hotter than the melting point of most metals. This was the foundation of modern oxyacetylene welding.^[3]

In 1886 an inventor who was awarded over 700 patents by the name of Elihu Thomson came up with resistance welding! Not only did he make resistance welding possible, but we still benefit from many of his other electrical inventions. This was the start of the modern welding age sparking inventor’s minds on how to join metals in different ways.^[4]

Welding Processes

Arc welding

Arc welding is the fusion of two pieces of metal by an electric arc between the pieces being joined and an electrode that is guided along the joint between the pieces.^[5]

Gas welding

Gas welding is a welding process in which the required temperature is attained by flames obtained from the combustion of fuel gases with oxygen. This is the most common welding process, primarily used for pipes and repair work.^[6]

Resistance welding

Resistance welding is a welding process that uses heat produced by the resistance of the work piece to an electrical current.

Solid state welding

Solid state welding is a welding process that uses pressure and initimate contact to bond two metals.

Other welding processes

Advantages of Welding

Strong and tight joining
Cost effectiveness
Simplicity of welded structures design
Welding processes may be mechanized and automated

Basic Safety Equipment for Welding

When it comes to welding, safety equipment is an Absolute Must! Some of the basics are:

A welding helmet with the proper shade lens for the process and amperage used when welding or the proper eye gear.
Safety glasses.
Leather welding gloves that are designed for welding.
Fire retardant long sleeve shirt or a leather welding jacket.
Pants that are made of cotton (preferably jeans) or are fire retardant.
Leather boots that are high enough (6" or higher) for your pants to overlap them.
Proper ventilation^[4]