Shafts

BY

Hashim Hasnain Hadi Ghulam Sarwar Muhammad Junaid Ashter Abbas

5th SemesterB.E Mechanical

Session 2013-2014

PREPRATION

Materials usedTypes of shafts

Stresses in shaftsDesign of shaftsShafts subjected to bending moment onlyTypes of shaft coupling

Introduction of Shaft

We Shall Focus on:

Shaft Rotating machine element.

 used to transmit power from one part to another part of a machine.

  pulleys and gears are mounted on it.

Transmit torque and bending moment

Types of Shafts

Transmission Shaft

Machine Shaft

Line Shaft

Materials used for shafts

Properties of materials used in shafts: High Strength Good machinability Low notch sensitivity factor Good heat treatment properties High wear resistance

Carbon steels of grades: 40c8, 45c8, 50c4 and 50c12.

Stresses in Shafts Shear stress due to transmission of torque.

Bending Stress due to forces upon machine elements: Pulley Gear Weight of shaft itself

Stresses due to combined torsional and bending loads.

Design of shafts Design Basis on:

Strength

Rigidity & Stiffness

CONTINUE…. On the basis of strength:

Twisting moment

Bending moment

Twisting and bending moments

Axial load in addition to combined Twisting and bending moments

Bending twisting

What is Bending of Shaft?

Shaft subjected to Bending Moment only

Types of Shaft Couplings

coupling

Rigid coupling

Sleeve coupling

Flange coupling

Compression coupling

Flexible coupling

Bushed Pin Type

CouplingUniversal Coupling

Oldham Coupling

Rigid Coupling

Sleeve coupling

Connect two perfectly aligned shafts

Type of rigid coupling

Made of cast iron

Fitted over the ends of two shafts by means of gib head key

Clamp or Compression Coupling

Flange coupling

Muff is divided into two parts which are bolted together Cast iron

Type of rigid coupling

Made of cast iron

Fitted over the ends of two shafts by means of gib head key

Flexible Coupling

Bushed pin type flexible coupling Connect two misaligned shafts

Modification of rigid type flange coupling

Use pins

Rubber or leather bushes are used

Oldham Coupling

Universal coupling

Connect two lateral misaligned shafts

Also called hooke’s coupling

Connect two shafts whose axes intersect at a small angle

THANK YOU