Drum pump refers to the pump used to empty barrels, tanks, IBCs, and drums. Many of the liquids used in manufacturing and processing plants are delivered in 100 or 200 liter barrels and are too heavy to be emptied to empty the liquid in them. The drum pump consists of a vertical axis inside a narrow tube that fits within the opening of the drum. The pump motor is attached to the vertical axis at the top of the tube outside and above the drum and the pumping element is located at the end of the pivot within the drum. This configuration allows the drum to be emptied without tipping thus reducing the risk of spill and operator injury.
The main use of drum pumps is 55 gallon barrels but they are also used in 5, 15, 30, 55, 275 and 330 gallon containers. Drum pumps come in various shapes from simple turnstile to various other styles such as lever, siphon, dual diaphragm, electric, air, piston, etc.
Also referred to as Container Pumps, Barrel Pumps and Tote Pumps.
Video Drum pump
References
Source of the article : Wikipedia