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Given below are two statements, one is labelled as Assertion (A) and other as Reason (R). Choose the correct answer from the options given below. As

Question

Given below are two statements, one is labelled as Assertion (A) and other as Reason (R). Choose the correct answer from the options given below.
Assertion (A): Fire tube boilers do not operate at high pressures while water tube boilers operate at high pressures
Reason (R): Due to high temperature of ﬂue gases, ﬁre tubes may fail due to creep.

Both (A) and (R) are individually true and (R) is the correct explanation of (A)

(A) is false but (R) is true

Both (A) and (R) are individually true but (R) is not the correct explanation of (A)

(A) is true but (R) is false

Solution

Correct option is A

In fire tube boilers, the hot flue gases pass through tubes surrounded by water. The pressure is contained in a large shell, which becomes thick and heavy at high pressures, making it impractical. Water tube boilers, where water flows inside tubes and flue gases pass outside, can handle higher pressures efficiently because the tubes can withstand high pressure better than a large shell.
Creep is the gradual deformation under sustained stress and high temperature. Fire tubes are exposed to high-temperature flue gases, and if the temperature exceeds the material's limits, creep failure can occur. However, this is not the primary reason why fire tube boilers are not used for high pressures.