Unidirectional thread loading applications are best served by________________?
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Answer: C. buttress
Explanation
Unidirectional thread loading applications are best served by buttress threads due to their specialized profile. Buttress threads feature a nearly vertical load-bearing flank that handles exceptionally high axial loads in one direction. The sloping trailing flank minimizes radial wedging forces while maintaining high structural load transmission efficiency. Thread geometry determines how effectively axial forces are transmitted across fastener or power screw assemblies. Unlike symmetric V-threads, buttress threads are engineered specifically for unidirectional load applications. Manufacturing buttress threads requires specialized tooling to cut the asymmetrical load-bearing flank accurately.
Jack screws, hydraulic presses, and breech mechanisms in artillery rely on buttress threads for safe load handling. Applications involving heavy unidirectional thrust forces benefit from the high load capacity of buttress threads. Engineering designers select buttress threads when standard fasteners cannot safely sustain heavy one-way axial loads. Option A square threads are used for bidirectional power transmission but generate higher frictional resistance. Option B acme threads are designed for bidirectional lead screw positioning rather than heavy unidirectional loads. Options D and E are general purpose fastening threads that lack the high unidirectional load capacity of buttress threads.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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