Unit - I Spur Gears Introduction to gears : Gear Selection, material selection, Basic modes of tooth failure, Gear Lubrication Methods. Spur Gears : Number of teeth and face width, Force analysis, Beam strength (Lewis) equation, Velocity factor, Service factor, Load concentration factor, Effective load on gear, Wear strength (Buckingham’s) equation, Estimation of module based on beam and wear strength, Estimation of dynamic tooth load by velocity factor and Buckingham’s equation. (Chapter - 1) Unit - II Helical and Bevel Gears Types of helical and Bevel gears, Terminology, Virtual number of teeth, and force analysis of Helical and Straight Bevel Gear. Design of Helical and Straight Bevel Gear based on Beam Strength, Wear strength and estimation of effective load based on Velocity factor ( Barth factor) and Buckingham’s equation. Mountings of Bevel Gear. ( No numerical on force analysis of helical & Bevel Gear) (Chapters - 2, 3) Unit - III Rolling Contact Bearings Types of rolling contact Bearings, Static and dynamic load carrying capacities, Stribeck’s Equation, Equivalent bearing load, Load- life relationship, Selection of bearing life Selection of rolling contact bearings from manufacturer’s catalog, Design for cyclic loads and speed, bearing with probability of survival other than 90%. Taper roller bearing: Force analysis and selection criteria. (Theoretical Treatment only) (Chapter - 4) Unit - IV Worm and worm gear terminology and proportions of worm and worm gears, Force analysis of worm gear drives, Friction in Worm gears, efficiency of worm gears, Worm and worm gear material, Strength and wear ratings of worm gears (Bending stress factor, speed factor, surface stress factor, zone factor) IS 1443-1974, Thermal consideration in worm gear drive, Types of failures in worm gear drives, Methods of lubrication. (Chapter - 5) Unit - V Belt drive : Materials and construction of flat and V belts, geometric relationships for length of belt, power rating of belts, concept of slip & creep, initial tension, effect of centrifugal force, maximum power condition, Selection of Flat and V-belts from manufacturer’s catalog, belt tensioning methods, relative advantages and limitations of Flat and V- belts, construction and applications of timing belts. Wire Ropes (Theoretical Treatment Only) : Construction of wire ropes, lay of wire rope, stresses in wire rope, selection of wire ropes, rope drums construction and design. Chain Drives (Theoretical Treatment Only) : Types of chains and its Geometry, selection criteria for chain drive, Polygon effect of chain, Modes of failure for chain, Lubrication of chains. (Chapter - 6) UNIT VI : Classification of sliding contact bearing. Lubricating oils : Properties, additives, selection of lubricating oils, Properties & selection of bearing materials. Hydrodynamic Lubrication : Theory of Hydrodynamic Lubrication, Pressure Development in oil film, 2DBasic Reynolds Equation, Somerfield number, Raimondi and Boyd method, Thermal considerations, Parameters of bearing design, Length to Diameter ratio, Unit bearing Pressure, Radial Clearance, minimum oil film thickness. (Chapter - 7)
