Lubricating oil in a journal bearing must be introduced directly at the location where the applied load is________________?
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Answer: A. nil or lightest
Explanation
Lubricating oil in a journal bearing must be introduced directly at the location where the applied load is lightest. Introducing oil at the point of minimum pressure allows the lubricant to enter easily without fighting high film pressures. The rotating journal then drags this fresh oil supply smoothly into the converging high pressure load zone. Journal bearing pressure distribution varies from zero at the inlet to a maximum value near the bottom load zone. Supplying oil under low pressure or at the unloaded side ensures continuous replenishment of the lubricating film. Proper oil inlet placement prevents starvation and maintains the hydrodynamic wedge required for low friction operation.
Option B is incorrect because introducing oil at the maximum load point would fight against extreme hydrodynamic pressure. Option C is wrong because oil should be fed specifically into the low load zone rather than average pressure areas. Options D and E are false because correct lubricant introduction points are strictly determined by bearing load mechanics.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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