[2026 Condition Analysis] Why is a safety valve not installed when the pressure in the feedwater system is higher than that in the drum?

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The last edit to this post was made by The one on 2026-5-5 06:26. Firstly, the pressure in the feedwater system is limited by the pressure at the outlet of the feedwater pump; it cannot increase indefinitely. The maximum pressure it can reach is equal to the highest pressure achievable when the outlet of the feedwater pump is completely closed. As long as the feedwater system can withstand this pressure, it will not be damaged. Thanks to the safety valves, the pressure in the steam system can be maintained at a certain level when it rises abnormally, thereby preventing damage to the equipment; otherwise, excessive pressure could lead to an explosion and cause more serious accidents.       On the other hand, water is almost incompressible, and the volume of water supply systems is small; even if such systems are damaged due to insufficient strength, the pressure drops rapidly, so no explosion occurs and no serious equipment or personal injuries result. Therefore, the feedwater systems of ordinary boilers, except for those equipped with cast-iron economizers, do not have safety valves.