TECHNICAL SEMINAR ONTWEEL

Guided byP.Salonika Sravani(Asst.Prof Mec)

Presented byK.Rajasekhar Reddy15705A0326

ANNAMACHARYA INSTITUTE OF TECHNOLOGY &SCIENCES

DEPARTMENT OF MECHANICAL ENGINEERING

CONTENTS What is a pneumatic tyre and drawbacks What is a Tweel? What makes tyres airless? How does it works? Advantages Disadvantages Applications Conclusion References

Pneumatic tyres A pneumatic, or air-filled, tyre is made

of an air tight inner core filled with

pressurized air.

The pressure of the air inside the tyre is

greater than atmospheric air pressure, so

the tyre remains inflated even with the

weight of a vehicle resting on it.

It gives a certain degree a cushioning

effect as the tyre hits bumps in the road.

Drawbacks Puncture or Blowout.

A blowout at high speeds can lead

to a dangerous car accident.

Variations in air

pressure changes tyre

performance.

Can blow out by gunfire or

explosion.

What is Tweel? The name “Tweel” is the contraction in English of “ t yre” and “W h eel”. Rather than a wheel + a tyre , we now

have a single product TWEEL. Mounting and removal operation will be simpler. To start with, Tweels could be fitted on vehicles with small wheels, such as wheelchairs, thus substantially improving the mobility of disabled people.

“Tweel” is nothing but a air less (or) Non pneaumatic tyres Airless tyres or Non-pneumatic tyres (NPT) , are tyres that are not

supported by air pressure.

What makes tyre “AIRLESS”?

The structure of SPOKES stretching along the inner side of tyres supporting the weight of the vehicle.

A synthetic resin that becomes flexible when heated, can be processed into a variety of shapes, and become hard when cooled.

The changes from heating and cooling can generally repeated , making it easy to both mold and recycle the material

Why Tweel?

The heart of Tweel innovation is its simple looking hub and spoke design that replaces the need for air pressure while delivering performance previously only available from pneumatic tyres.

Tweel still delivers pneumatic –like performance weight-carrying capacity, ride comfort, and the ability to “envelope” road hazards.

Main parts of TWEEL1. TREAD2. SHEER BAND3. DEFORMEBLE

WHEEL4. FLEXIBLE

SPOKES

How does it works?.

Flexible spokes are fused with a flexible wheel which deforms to absorb shock.

The Tweel also has a unique capability to have different vertical and lateral stiffness.

The vertical stiffness affects ride comfort, and lateral stiffness affects handling and cornering.

The best of both worlds, ride comfort and superb handling!

On working the Tweel is a single unit, though it actually begins an assembly of four pieces bonded together: the hub, polyurethane spoke section, a “sheer band” surrounding the spoke and the tread band.

The sheer band surrounding the spokes effectively takes the place of air pressure, distributing the load.

The tread is similar in appearance to a conventional tyre.

Tweel works well over rocky terrains, so it should work well for four-wheel vehicles too.

The tension of the sheer band on the spokes and the strength of spokes themselves replace the air pressure of a traditional tyre.

The tread is then attached to the sheer band.The Tweel looks sort of like a very large,

futuristic bicycle wheel.

When the Tweel put to the road, the spokes absorb road impact the same way air pressure does in pneumatic tyres.

The tread and sheer bands deform temporarily as the spokes bend, then quickly spring back into shape.

Advantages Eliminates air leaks or tyre blow outs.

No maintenance required.

Facilitate recycling.

Remains mobile even with some of the spokes are damaged or missing.

Durability & Long Life.

Can take gunfire or explosion.

Less environmental impact.

Disadvantages

Lack of adjustability.

Vibration.

Different Manufacturing technique.

Not as economic as pneumatic tyres.

Applications

Used on some small vehicles such as riding lawn mowers andmotorized golf carts.

In backhoe or bulldozers.

continued..

For Military vehicles

Also used inAll Terrine Vehicles (ATV)

ConclusionFor years, vehicles have been running on pneumatic tyres

and there was almost a full stop for any further

improvement of tyres. In 20th century the engineers have

come up with a new concept where the tyres never require

air, if the drawbacks that are being encountered presently

are and improved then there is good future for these tyres.

And the vehicles can run without the necessity of air.

[1].Rhyne, T. B., and Cron, S. M., “Development of a Non-Pneumatic Wheel,” Tire Science and Technology, Volume 34, Number 3, July-September 2006

[3]. Dr.Joshi.C.Haran, “Static analysis of airless tyres “,International Journal of Scientific and Research Publications, Volume 3, Issue 8, August 2013

[3]. htpps://www.michelin.com last visited on 26/03/14 at 8 am

REFERENCES