Solve this multiple-choice question and choose the correct option.

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Power-transmitting screw threads: best choice when power is transmitted in one direction only Select the thread form that is mechanically best suited for heavy load transmission predominantly in a single direction. Choose the correct option.

Difficulty: Easy

Square threads
Acme threads
Knuckle threads
Buttress threads

Correct Answer: Buttress threads

Explanation:

ConceptButtress threads combine the high efficiency of a square thread in the load direction with a stronger tooth form, making them ideal where heavy force acts primarily in one direction (e.g., presses, jacks).

Why others are less suitableSquare is efficient but weaker at the root; Acme is stronger but less efficient; Knuckle is for rough/rolling engagement, not precision power screws.

Final AnswerButtress threads

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