Which among following types of threads has lead and pitch as equal?

Explanation:

Lead:

• Lead is the distance a threaded component moves along the matching component during one complete revolution.
• For a single start thread, the lead is equal to the pitch.

Single-start thread:

• A single-start thread has one continuous thread running along the body of the screw.
• They are usually cheap and commonly used.
• For a single start thread, the lead is equal to the pitch.

Multi-start thread:

• A multi-start thread consists of two or more intertwined running parallel to one another.
• The lead distance of a double start thread is twice that of the single start thread and a triple start thread has thrice that of the single start thread.

​For triple start thread:

Lead = 3 × Pitch

• Multi-start threads maintain a shallow thread depth relative to their longer lead distance. Another design advantage of a multi-start thread is that more contact surface is engaged in a single thread rotation.