What critical conditions would trigger a boiler trip?

A boiler trip is an emergency shutdown of the boiler, automatically initiated by the Boiler Management System (BMS) to prevent catastrophic damage to the equipment or harm to personnel. Several critical conditions would trigger a boiler trip. First, low water level in the steam drum is a primary trigger. If the water level drops below a safe minimum, it exposes the boiler tubes to overheating and potential failure. Second, high steam pressure triggers a trip to prevent over-pressurization and potential explosions. Third, flame failure triggers an immediate fuel shutoff to prevent the accumulation of unburned fuel in the furnace. Fourth, loss of forced draft or induced draft fans stops air flow and can lead to a fuel-rich condition and potential explosion. Fifth, high furnace pressure triggers a trip to prevent damage to the furnace structure. Sixth, tube failure triggers a trip because it can lead to a rapid loss of pressure and potential for steam or water leaks. Seventh, loss of all feedwater pumps is a serious condition leading to a rapid water level decrease. Eighth, a turbine trip can also trigger a boiler trip, especially if the boiler is supplying steam solely to that turbine. Ninth, certain earthquake events may trigger a shutdown. The precise trip settings and logic are carefully designed to provide maximum safety and reliability.