Boiler feedwater regulation

(mechanical engineering) Addition of water to the steam-generating unit at a rate commensurate with the removal of steam from the unit.

Addition of water to a steam-generating unit at a rate commensurate with the removal of steam from the unit. The addition of water to a boiler requires a feedwater pump or some other device that will develop a pressure higher than that of the steam generated. Means also are required to control the rate at which water is added. See also Boiler.

Variations of water level in the steam unit usually are due to changes in the rate of steam generation because such changes affect the steam output and the volume of the steam below the water level. Changes in water level can be compensated by use of automatic control which, primarily, regulates the rate of feedwater flow to be equal to the rate of steam output, as determined by metering equipment; the control then readjusts the rate of feedwater flow to maintain the water level within the prescribed normal range. See also Boiler feedwater.