Question

A thread with vertical and parallel flanks is called

• A. Square thread
• B. Triangular thread
• C. Knuckle thread
• D. V-thread

Hint:

Square threads = vertical flanks. Used in jacks, lead screws, and presses for power transmission.

Answer 1

The Correct Option is A

Threads are classified by their flank angles and profile shapes.
- Square threads are defined by their vertical and parallel flanks. This design provides high efficiency and is suitable for transmitting motion and power in one direction.
- Triangular threads (like metric or unified threads) have angled flanks, typically at 60°.
- V-threads are similar to triangular threads but with sharper angles.
- Knuckle threads have rounded crests and roots, making them ideal for rough applications like bottle caps.
Only square threads have the characteristic of vertical and parallel flanks, making option (A) correct.