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 v1
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

11. ADVANTAGES WORM
AND WORM WHEEL
• High speed reduction 300:1
• worm and worm wheel are is locking system
• With in less space this worm and worm wheel can be
arranged

12. DIS ADVANTAGES
• Manufacturing cost is high
• Heavy power loss
• Efficiency is low

13. 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

14. INDUSTRIAL APPLICATIONS

15. THANK YOU