शाफ्ट आधारित प्रणाली में, शाफ्ट के आकार का ऊपरी विचलन_______ होता है।

Question

Question

This question was previously asked in

JKSSB JE ME 2015 Official Paper

Answer 1

Explanation:

For making hole and shaft assembly two types of systems is adopted internationally. They are:

Shaft basis system:

In this system, the size of the shaft is kept constant, and the diameter of the hole is varied to give the various fits.
The basic size of the shaft is taken as the upper size limit of the shaft i.e. upper deviation of the shaft is zero.

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Hole basis system:

In this system, the designation of tolerance of the hole is kept constant and the shaft diameter is varied to obtain the various types of fits.
The basic size of the hole is taken as the lower size limit of the hole i.e. lower deviation of the hole is zero.
In general practice, the hole basis system is adopted.
Various tools like standard drills, reamers, broachers are easily available and shafts are later given tolerance to produce the desired fit.

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