A positive displacement pump that consists of a chamber containing gears, cams, screws, vanes, plungers or similar elements actuated by relative rotation of the drive shaft or casing and which has no separate inlet and outlet valves.

A thermodynamic turbine in which steam is made to do work by expanding so as to create kinetic energy by acting on moving blades attached to a disc or drum.

A vessel intended to contain fluid for storage. Typically a receiving or collecting function for further distribution. Typically with a vertical and cylindrical or square shape and a flat or conical bottom.

An expander of the turbine type used to reduce the pressure of a gas flow by leading it through a turbine rotor by which the recovered energy is transferred into rotational energy for either power generation or mechanical drive application.