Besides shear forces, a machine key experiences side pressures known as_________________?
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Answer: A. bearing stresses
Explanation
In addition to shear forces, machine keys experience crushing side pressures known as bearing stresses. As a shaft transmits torque, the key presses against the keyways of both the shaft and the rotating hub. This contact force creates distributed compressive loading across the working side faces of the machine key. Machine keys are removable fasteners used to secure rotating elements like gears and pulleys onto drive shafts. Design calculations check keys for both direct shear failure along the longitudinal plane and bearing crushing failures. Selecting appropriate key materials prevents premature yielding under combined torsional and bearing stress loads.
Fatigue stresses involve fluctuating cyclic loads rather than direct crushing pressures exerted by torque transmission. Crushing stresses are technically similar, but bearing stress is the standard engineering term for key face contact. Resultant stresses combine multiple load vectors rather than identifying the specific side pressure on the key.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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