Preheater protection valve

To increase the efficiency of a steam boiler system, the feed water flowing from the feed water tank to the boiler is heated by a preheater. The preheater is a heat exchanger through whose pipes the feed water flows. The pipes are exposed to extraction steam from the turbine from the outside. In the event of a leak in the pipe system, water flows at higher pressure into the steam chamber at lower pressure. In order to prevent damage caused by feed water entering the turbine or by the build-up of impermissible pressure in the preheater jacket, the preheater must be disconnected from the feed water pressure line as quickly as possible. This is achieved by means of a preheater safety device, i.e. self-controlled quick-closing valves located at the inlet and outlet of the preheater.