Question 88Steam Plants - Assistant Engineer

The correct answer is D) priming and carryover. When a boiler with higher steam pressure is brought online while another boiler with lower steam pressure is already operating, there is a risk of priming and carryover. Priming is the rapid entrainment of boiler water into the steam, which can lead to water droplets being carried over into the steam system. This can cause damage to equipment and pose a safety hazard. The pressure differential between the two boilers can drive this undesirable condition, which is why it is important to carefully manage boiler pressures when bringing additional units online. The other answer choices are incorrect because: A) Low water is not directly related to the pressure differential between boilers. B) An overloaded superheater is not a concern in this scenario. C) Thermal shock is not the primary issue when boilers with different pressures are brought online together.