Question 166Steam Plants - 1st Asst/Chief

70% to pass

A water-tube boiler can be laid up either wet or dry. If it is to be laid up wet, you should _______________.

Adrain and refill the boiler when the pH goes above 6

Bdrain and refill the boiler each week

Ccompletely fill the boiler with deaerated feed water and maintain a slight pressure

Dcompletely fill the boiler with water, then blow down to steaming level

AI Explanation

The correct answer is C) completely fill the boiler with deaerated feed water and maintain a slight pressure. When a water-tube boiler is laid up wet, it should be completely filled with deaerated feed water and a slight pressure should be maintained. This helps prevent corrosion and oxidation of the internal surfaces by keeping air out of the boiler. Draining and refilling the boiler periodically (options A and B) is not necessary when it is properly laid up with deaerated water and a slight pressure. Blowing down to the steaming level (option D) would leave part of the boiler exposed to air, increasing the risk of corrosion.