A pump is a mechanical device for moving a fluid from a lower to a higher location, or from a lower to a higher pressure area.

The fluid can be any type of liquid or gas, and pumps may be classified in many number of ways according to their purpose, specifications, environment, design, etc.

Oil refineries process crude oil into fuels such as gasoline, kerosene, diesel oil, heavy oil, and into other petroleum products such as naphtha, lubricating oil, and asphalt. Then, using petroleum products and natural gas as raw materials the petrochemical industry produces a wide variety of other chemical products.

Process pumps play a crucial role in transporting both the raw materials and the products of the production processes at these refineries and petrochemical plants.

Petrochemical production involves three different phases of processing: the conversion of oil and other raw materials into more easily usable form; the separation and refining of the desired substances from these converted materials; and the final processing of these substances into petrochemical products. Process pumps are an indispensable part of each of these three phases.

Process pumps handle a wide range and variety of fluids, often at the extremes of temperature (high and supercooled), pressure (high and low), and corrosive potential. In addition, since suspension of production due to equipment malfunction at a major plant can have an enormous impact on operations, these pumps must be highly dependable. For this reason, the American Petroleum Institute 610 Standard is applied to many process pumps.

Today reduction of CO₂ and promotion of energy conservation are being advocated throughout the world in order to prevent global warming. Even in aging refineries and plants, replacement of old process pumps with the latest high-efficiency equipment has been pointed to as an effective and promising means for conserving energy.