mechanical engineering Mechanical engineering is the study of physical machines and mechanism (engineering), mechanisms that may involve force and movement. It is an engineering branch that combines engineering physics and engineering mathematics, mathematics principl ...

, a shaft is a rotating

machine element Machine element or hardware refers to an elementary component of a machine. These elements consist of three basic types: # ''Structural element, structural components'' such as frame members, Bearing (mechanical), bearings, axles, Spline (mechan ...

, usually circular in cross section, which is used to transmit power from one part to another, or from a

machine A machine is a physical system that uses power to apply forces and control movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to natural biological macromol ...

which produces power to a machine which absorbs power.

Types

They are mainly classified into two types. * Transmission shafts are used to transmit power between the source and the machine absorbing power; e.g. counter shafts and line shafts. * Machine shafts are the integral part of the

itself; e.g.

crankshaft A crankshaft is a mechanical component used in a reciprocating engine, piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating Shaft (mechanical engineering), shaft containing one or more crankpins, ...

. *Axle shaft. *Spindle shaft.

Materials

The material used for ordinary shafts is mild steel. When high strength is required, an

alloy steel Alloy steel is steel that is Alloy, alloyed with a variety of elements in amounts between 1.0% and 50% by weight, typically to improve its List of materials properties#Mechanical properties, mechanical properties. Types Alloy steels divide into ...

such as

nickel Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slo ...

, 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.

Standard sizes

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

Machine shafts

* Up to 25 mm steps of 0.5 mm

Transmission shafts

* 25 mm to 60 mm with 5 mm steps * 60 mm to 110 mm with 10 mm steps * 110 mm to 140 mm with 15 mm steps * 140 mm to 500 mm with 20 mm steps The

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

s 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. #

Shear stress Shear stress (often denoted by , Greek alphabet, Greek: tau) is the component of stress (physics), stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross secti ...

es due to the transmission of

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

(due to torsional load). # 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. # Stresses due to combined torsional and

bending In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external Structural load, load applied perpendicularly to a longitudinal axis of the element. The structural eleme ...

loads.

References

External links

Online verification of shafts according standard
{{Authority control Machines Mechanical engineering Kinematics Articles containing video clips Shaft drives