Worm and Worm wheel Gears

worm and worm wheel gears, design, failures, applications

1. A Technical Seminar report on DESIGN AND APPLICATIONS OF WORM AND WORM WHEEL GEAR Submitted by Mr. CH.D.JAYA TEJA (16481D1504)   In partial fulfilment of the requirements for the award of the degree of MASTER OF TECHNOLOGY In MACHINE DESIGN Submitted to Mr. K.Ch. KISHOR KUMAR, M.Tech, (Ph.D) Assoc. Professor DEPARTMENT OF MECHANICAL ENGINEERING GUDLAVALLERU ENGINEERING COLLEGE (An Autonomous Institute with permanent affiliation to JNTUK, Kakinada.) Seshadri Rao Knowledge Village, Gudlavalleru-521356 2016-17

2. Worm and worm wheel If the axis of the gears are non-parallel and non intersecting that type of gears are called worm and worm wheel gears It is used to transmit power at high velocity ratios 300:1 It is a multi start threaded geared system worm is a multi threaded shaft Worm Wheel is simple spur gear Worm is made of phosphorous bronze or cast iron because of high thermal conductivity Worm wheel is made of alloy steel due to low thermal conductivity

3. Types of worms Cone or double enveloping worm Cylindrical or straight worm

4. Types of worm wheels STRAIGHT FACING WORM GEAR HOBBED STRAIGHT FACING WORM GEAR CONCAVE FACE WORM GEAR

5. Design 0f worm and worm wheel  

7. To determine the diameter of the wheel Calculating v 1 sliding velocity Face width of wheel

8. length of worm efficiency Friction coefficient μ for grounded worm we have to increase length final length of the cut portion of the worm considering the case of dynamic un balance is L2= λ*π* Worm wheel diameter

9. Failures of worm and wheel

10. Advantages worm and worm wheel High speed reduction 300:1 worm and worm wheel are is locking system With in less space t his worm and worm wheel can be arranged

11. Dis advantages Manufacturing cost is high Heavy power loss Efficiency is low

12. Applications Fast braking or stopping is desired—lifts, elevators and hoists Noise is concern—theaters. Airports and elevators Space is concern– packaging equipment's, small machinery and conveyors Shock loading– rock crushers and other heavy duty machinery

13. Industrial applications

14. Thank you