How Steam Shovels Work

Steam Power

• A steam shovel is a motorized shovel that uses a steam engine as its source of power. First patented by William Otis in 1839, steam shovels, like other steam engine machines, used a boiler for making steam and a motor, or engine, to transform the steam to mechanical energy. The steam engine drove both the shovel, or basket, of the steam engine, as well as its wheels or tracked drive system.

Excavation

• Steam shovels were used to excavate and move large quantities of material. The average man can move about 12 cubic yards of earth per day, while the earliest steam shovels could move 300 cubic yards or more per day. The working end of the steam shovels had a bucket that would dig into the ground to pick up material. The operator would then raise the bucket and move the arm of the steam shovel to remove the material and transfer it -- often into a truck or barge that would take it somewhere else.

Time Frame

• Steam shovels continued being used from the time of their invention until the 1930s, when they were mostly replaced by diesel engine excavators. Steam shovels were used extensively during the construction of the Panama Canal from 1904 to 1914.

Legacy

• Steam shovels used steam boilers to generate power. Once the internal combustion engine, and more specifically the diesel engine, came into widespread use, steam shovels were eclipsed by more powerful and efficient forms of shovels and excavation equipment. The newer machines use the diesel or gasoline engines in the same way the steam shovel used its boiler and engine power system.