Articles Posted in the " Theory of Machines " Category

  • BELT DRIVE

    BELT DRIVE

    Belt Drive  Definition of a belt  It is in the form of a loop. It connects mechanically two shafts for transmitting power smoothly. MATERIALS OF BELTS (I) Leather (ii) Rubber (iii) Fiber/cotton (iv) Balata Standard Thicknesses of belts 5, 6.5, 8, 10 and 12 mm are the standard thicknesses. Standard widths of flat belts 25, 32, […]


  • Fatigue

    Fatigue

    Fatigue PRACTICAL FATIGUE FAILURES  Shafts, buckets, disks and blades of jet engines  Crank shafts of ground vehicles  Gears used in ground vehicles, mining equipment and marine equipment  Compression springs n ground automobiles Anything or everything in motion under cyclic loading of one kind or the other.  Low amplitude and high cycle loading is the common […]


  • Fatigue Mechanical Life Design-A Review- ENDURANCE LIMIT

    Fatigue Mechanical Life Design-A Review- ENDURANCE LIMIT

      Fatigue Mechanical Life Design-A Review- ENDURANCE LIMIT Fatigue is due to a reversible stress. Material fails at a much lower stress under reversible stress. In order to avoid fatigue failure, a stress is found at which a material never fails even after infinite reversals. This stress is called the endurance limit. FACTORS AFFECTING ENDURANCE […]


  • Fatigue

    Fatigue

       Fatigue  Notable Fatigue Failures Versailles train disaster The 1862 Hartley Colliery Disaster De Havilland Comet crash Alexander L. Kielland oil platform capsizing The 1919 Great Molasses Flood, the 1948 Northwest Airlines Flight 421 crash, the 1957 of Philippine President aircraft crash, the 1965 capsize of UK’s first offshore oil plate form, the 1968 Los […]


  • Fatigue Mechanical Life Design-A Review-1

    Fatigue Mechanical Life Design-A Review-1

      Fatigue Mechanical Life Design-A Review-1 Fatigue Mechanical Life Design-A Review  Abstract Fatigue is due to cyclic loading and unloading of one kind or the other. It is due to the presence of discontinuities in the material. Mostly fatigue failure is progressive and plastic in nature. It is due to the nucleation, growth and propagation […]


  • BALANCING AND UNBALANCING–Introduction

    BALANCING AND UNBALANCING–Introduction

    BALANCING AND UNBALANCING FORCES There are many different forces like contact force, gravity force, inertia force, wind force, fluid pressure force, static force, thermal force, centrifugal , frictional force, pushing force, pulling force, seismic force, snow force, normal force, tangential force etc. Without a force no action like dancing, cycling, playing sports. Even a stationary […]


  • INTERVIEW SHORT QUESTION ANSWERS ON MACHINE DESIGN

    INTERVIEW SHORT QUESTION ANSWERS ON MACHINE DESIGN

    INTERVIEW SHORT QUESTION ANSWERS ON MACHINE DESIGN Definition of design It is a process to create an object/machine to perform the required function satisfactorily over a reasonable period of time (life) with minimum cost. Definition of design synthesis It is a process to find various alternatives of a product/mechanism  to achieve the desired function satisfactorily […]


  • THEORY OF MACHINES: HIGHLIGHTS

    THEORY OF MACHINES: HIGHLIGHTS

    THEORY OF MACHINES: HIGHLIGHTS  Lower pairs have line contact. Higher pairs have point contact or sliding contact. Rolling pairs have surface contact.Link is a resistant body which has relative motion but does not affect motion of other members (pendulum has one degree of freedom as θ).Piston and piston rod form one link since there is […]


  • INTERVIEW SHORT QUESTION ANSWERS-GEARS

    INTERVIEW SHORT QUESTION ANSWERS-GEARS

    INTERVIEW SHORT QUESTION ANSWERS-GEARS Discuss the advantages and disadvantages of an involutes profile. A. Advantages of involutes profile Manufacturing is accurate and easy. Pressure angle is constant Velocity ratio remains the same by the change of center distance.  Disadvantages of involutes profile Followings are the disadvantages. (i) Interference (ii)  Vibrations (iii)  Noise (iv)  Heat generation (v) Life reduction […]


  • INTERVIEW SHORT QUESTION ANSWERS-Flywheel theory

    INTERVIEW SHORT QUESTION ANSWERS-Flywheel theory

    INTERVIEW SHORT QUESTION ANSWERS—Flywheels theory Q. Compare the different types of flywheels. A. Comparison of high and low speed flywheels Sr. No. High speed flywheels Low speed flywheels 1. Speed is 30000 to 60000 RPM Speed is less than 10000 RPM 2. Light weight Heavy weight 3. Easy commissioning and requires less maintenance Tedious commissioning and […]