The fluid replenisher is a supplementary tank into which liquid is forced from the brake cylinder when the liquid expands due to its heating during intensive firing. Liquid is returned to the brake cylinder when its volume decreases upon cooling. Replenisher tank 1 is connected by tube 4 to brake cylinder 2, being separated by partition 3. The replenisher tank is filled with liquid and air (at a pressure of 1 atm and higher). Upon intensive firing the volume of the air is reduced because surplus liquid passes into tank 1 from cylinder 2 through tube 4. This raises the pressure of the air. As the liquid cools, it is forced in the required quantity by the air pressure back into cylinder 2.
$3783$SHP,FD$