Question 270General Subjects - Assistant Engineer

70% to pass

Referring to the illustrated impulse steam trap, what would be the effect of threading the control cylinder "E" upward out of the trap body? Illustration GS-0002

Diagram for USCG General Subjects Assistant: Referring to the illustrated impulse steam trap, what would be the effect of...

AThe clearance between the reverse taper of the control cylinder's inner wall and the periphery of the valve disk will decrease, and as a result, the pressure drop across the periphery of the valve disk will increase.

BThe clearance between the reverse taper of the control cylinder's inner wall and the periphery of the valve disk will decrease, and as a result, the pressure drop across the periphery of the valve disk will decrease.

CThe clearance between the reverse taper of the control cylinder's inner wall and the periphery of the valve disk will increase, and as a result, the pressure drop across the periphery of the valve disk will decrease.

DThe clearance between the reverse taper of the control cylinder's inner wall and the periphery of the valve disk will increase, and as a result, the pressure drop across the periphery of the valve disk will increase.

AI Explanation

The correct answer is A. Unscrewing the control cylinder (E) upward would decrease the clearance between its reverse taper and the valve disk's periphery. This would increase the pressure drop across the valve disk, as the restricted flow path would create a higher pressure differential. The other options are incorrect because: B) Decreasing the clearance would actually increase the pressure drop, not decrease it. C) Increasing the clearance would decrease the pressure drop, the opposite of what is stated. D) Increasing the clearance would decrease the pressure drop, not increase it.