Machine Design - Study Mode

[#216] Surface endurance limit of gear material is dependent upon its
Correct Answer

(C) Brinell hardness number

[#217] Lewis equation in gears is used to find the
Correct Answer

(C) Compressive stress in bending

[#218] Buttress threads are usually found on
Correct Answer

(C) Spindles of bench vices

Explanation

Solution: The correct answer is (C) Spindles of bench vices . Let's break down why: Buttress threads are special types of threads designed to handle heavy loads in one direction . Think of them like a ramp on one side and a vertical wall on the other. * Option A: Screw cutting lathes: Lathes use various threads, but not typically buttress threads for their main operation. * Option B: Feed mechanisms: While feed mechanisms require movement, they don't usually need the one-directional, high-load capacity of buttress threads. * Option C: Spindles of bench vices: Bench vices are all about applying a strong force in one direction to hold an object securely. The buttress thread is perfect for this! When you tighten a vice, you want a strong, secure grip *without* the vice easily loosening. The ramp allows for easy tightening, and the vertical face prevents slipping under load. This is the most common and ideal application for buttress threads. * Option D: Railway carriage couplings: Railway couplings require a strong connection, but other thread types (like ACME threads) are generally preferred due to their ease of manufacture and suitability for bidirectional forces.

[#219] The acme threads are usually found on
Correct Answer

(D) Screw cutting lathes

[#220] The square threads are usually found on
Correct Answer

(C) Feed mechanism of machine tools