airless tyres pneumatic tyre non pneumatic tyres additive manufacturing

1. SEMINAR
ON

2. CONTENTS
1) PNEUMATIC TYRES
2) NON-PNEUMATIC TYRES
3) ADDITIVE MANUFACTURING
4) DRAWBACKS OF PNEUMATIC TYRES
5) ROLE OF AIRLESS TYRES
6) TECHNOLOGY USED IN AIRLESS TYRES

3. Pneumatic tyres
A PNEUMATIC OR AIR FILLED TYRE IS
MADE OF AIR TIGHT INNER CORE FILLED
WITH PRESSURISED AIR
THE PRESSURE OF THE AIR INSIDE THE
TIRE IS GREATER THAN THE
ATMOSPHERIC AIR PRESSURE
IT GIVES CERTAIN DEGREE OF
CUSHIONING EFFECT AS THE TYRE HITS
BUMPS IN THE ROAD

4. Non-pneumatic tyres(Air less tyres)
Tires that are not
supported by air
pressure
The airless tyre was
first developed by
Michelin
Also called as Tweel
which is merger of the
word tyre and wheel.

5. Additive manufacturing
• Additive manufacturing (AM) or additive layer
manufacturing (ALM) is the industrial production
name for 3D printing, a computer controlled
process that creates three dimensional objects by
depositing materials, usually in layers.
• Additive manufacturing is different from
traditional manufacturing as it allows a part to be
built layer-by-layer, whereas traditional
manufacturing often requires a part to be made
by joining separate components or by machining
away unwanted material to produce the part.

7. Drawbacks of pneumatic tyres
oPuncture or Blowout during
operation
oA blowout at high speeds can lead
to dangerous car accidents
oVariation in air pressure changes
tyre performance
oCan blow out by gun fire or
explosion

8. Role of Airless tyres in overcoming these
drawbacks
• Eliminates air leaks or tyre blow outs.
•
With no air pressure you are left with consistent economy and handling.
• Makes Vehicle more Efficient having high lateral strength for better handling
without a loss in comfort.
• Vehicle remains under control even in emergency brake
• Durability & Long Life.
• Can take gunfire or explosion.
• Less environmental impact.

9. Technology used in airless tyres
• Airless tire technology
features a unique spoke
structure designed to
support the weight of a
vehicle, effectively
eliminating the need to
periodically refill the
tires with air.

10. The Airless tyre doesn’t use a conventional wheel hub assembly. A solid
inner hub mounts to the shaft and is enclosed by polyurethane spokes
clothed in an exceedingly pattern of wedges.
A shear band is stretched across the spokes, forming the outer reaches of
the tyre. On that sits the tread, the half that comes to bear with the surface
of the road.
The cushion shaped by the air cornered within a standard tyre is replaced by
the strength of the spokes that receive the strain of the shear band. Placed
on the shear band is that the tread, the half that creates contact with the
surface of the road.

11. Once the Tweel is running on the road, the spokes absorb road defects
a similar method atmospheric pressure will within the case of gas tyres.
The versatile tread and shear bands deform briefly because the spokes
bend, then quickly return to the initial form. Totally different spoke
tensions are used and lateral stiffness can even vary.
However, once created the Tweel’s spoke tensions and lateral stiffness
can't be adjusted.

12. Environmental Effect
• Non-exhaust emissions (NEE) are particles
released into the air from brake wear, tyre wear,
road surface wear and resuspension of road dust
during on-road vehicle usage. No legislation is in
place to limit or reduce NEE, but they cause a great
deal of concern for air quality.
• Airless tyre have less wear and tire when
compared conventional tires.
• The main environmental advantage to the Airless
tyre is its very low rolling resistance, or the
constant force required to roll a wheel at a
constant speed under a certain vertical load

13. ENERGY LOSSES
• Most of the energy available in the fuel tank is lost in converting heat
into mechanical work in the engine, but about 20% of the energy
from the fuel makes it to the tires, and a significant percentage of this
is used to overcome the rolling resistance. Most of this rolling
resistance energy loss stems from the viscoelastic behaviour of
rubber materials.
Some of the energy required to deform rubber is stored as elastic
energy and is completely recovered when it is returned to its original
shape, but some is converted to heat and lost due to rubber’s partially
viscous behaviour . This energy loss under a load and unload cycle is
called hysteresis.

14. CONCLUSION
• Even though airless tyre have many advantages ,it has it’s own drawbacks too .
Manufacturing, working conditions, feasibility still need major optimisations. The
airless tyre technology is still under testing and hopefully we can see it in real
world use in near future.

15. R. Sanjeev Kumar, K. Vetrivel Kumar and T. Ramakrishna,
"Design optimization of Airless Tyre - NumericalApproach",
IOP Conference Series: Materials Science and Engineering,
vol. 1057, no. 1, p. 012032, 2021.
M. Abdullah Mir,
"Non Pneumatic tyres", INTERNATIONAL JOURNAL OF
RECENT TRENDS IN ENGINEERING &RESEARCH, vol. 6, no.
11, pp. 30-39, 2020.
Manuel Sardhinha
“Non Pneumatic tyre designs”
https://doi.org/10.1016/j.jclepro.2023.135917