Shaft (mechanical engineering)

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A shaft is a rotating machine element, usually circular in cross section, which is used to transmit power from one part to another, or from a machine which produces power to a machine which absorbs power.

Contents

Types

They are mainly classified into two types.

Materials

The material used for ordinary shafts is mild steel. When high strength is required, an alloy steel such as nickel, nickel-chromium or chromium-vanadium steel is used. Shafts are generally formed by hot rolling and finished to size by cold drawing or turning and grinding.[ citation needed ]

Standard sizes

Source: [1]

Machine shafts

Transmission shafts

The standard lengths of the shafts are 5 m, 6 m and 7 m.

Usually 1m to 5m is used.

Stresses

The following stresses are induced in the shafts.

  1. Shear stresses due to the transmission of torque (due to torsional load).
  2. Bending stresses (tensile or compressive) due to the forces acting upon the machine elements like gears and pulleys as well as the self weight of the shaft.
  3. Stresses due to combined torsional and bending loads.

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References

  1. Mahadevan K and Reddy K.Balaveera, (2015), 'Design data hand book', CBS publishers and Distributors (P) ltd., New-Delhi, ISBN   9788123923154