Question

For a triple threaded screw, the lead is 30 mm and the mean diameter of the screw is 80 mm, then the pitch of the screw is

• A. 30 mm
• B. 20 mm
• C. 10 mm
• D. 60 mm

Hint:

For multi-threaded screws, the lead is the distance the nut moves per revolution, and the pitch is the distance between two adjacent threads. The lead is equal to the pitch multiplied by the number of threads.

Answer 1

The Correct Option is C

Step 1: Understand the relationship between lead, pitch, and the number of threads.
For a screw with multiple threads, the relationship between the lead (\(L\)) and the pitch (\(P\)) is given by: \[ L = n \times P \] where:
\(L\) is the lead of the screw,
\(n\) is the number of threads (in this case, 3 for a triple-threaded screw),
\(P\) is the pitch of the screw (the distance between threads).
Step 2: Substitute the known values into the equation.
We are given the lead \(L = 30 \, \text{mm}\) and the number of threads \(n = 3\). We can solve for the pitch \(P\) as follows: \[ 30 = 3 \times P \] \[ P = \frac{30}{3} = 10 \, \text{mm} \] Thus, the pitch of the screw is \(10 \, \text{mm}\).