Pre Heater Change over Protection System
Are used and designed to bypass hight pressure feed-water around a group of heaters in the event of high water level in the shell caused by a defective tube or welding.
- ASME Class900-3200
- DN100-600 | 4"-24"
- T (°C)up to + 400°C
- DesignQuick closing Stop Valve, 3-Way quick closing Valve, pneumatic actuated pilot valve, FO
- MaterialsC-Steel, Mo-Steel, CrMo Steel
- BonnetPressure sealed bonnet
- Operation:Medium controlled
These valves are used to protect one or a group of preheaters in the event of damage to their high-pressure pipes. In the event of such a defect, the feed of the feed water must be shut off in a very short time and diverted through a bypass line. For this purpose, a quick-closing shuttle valve is installed in the pipe and a quick-closing check valve behind the preheater. The valves are controlled by their the own medium and will respond within a second time, so that protection can also be provided if electrical or pneumatic supply energies fail.
– Protect the feed-water heater steam jacked
– Protect the turbine extraction from excessive back pressure
– Allows the feed water heater to be isolated for inspection
– Allowing by passing of the heater during start-up at low turbine load
– Allowing by-passing of the heater at peak loads to increase power output from the turbine