immer-mobil TCN 8200 Mode D'emploi page 126

14 - Bead. This is the part that joins the tyre to the rim.
The bead point (a) is the inner corner. The spur (b) is the
inner part of the bead. The base (c) is the area resting
against the rim. The groove (d) is the concave part against
which the rim shoulder rests.
Tube type tyres. As a tyre has to contain pressurised air
for a long period of time, an air chamber is used. The
valve for inserting, maintaining, controlling and restoring
pressurised air is, in this case, part of the chamber.
Tubeless tyres. Tubeless tyres consist of a tyre with inner
sidewall lined with a thin layer of special impermeable
rubber, called a liner. This liner helps to maintain air
pressure in the casing. This type of tyres must be mounted
on specific rims, on which the valve is fixed directly.
II - Rim (Wheel). The rim is the rigid metal part which
connects the vehicle hub to the tyre, on a fixed but non-
permanent basis.
Rim profile. The rim profile is the shape of the section in
contact with the tyre. It is made with different geometric
shapes that serve to ensure: easy assembly of the tyre
(inserting the bead into the channel); safety on the move,
in terms of anchoring the bead in its seat.
When observing a section of the rim, it is possible to
identify different parts that compose it: a) rim width – b)
shoulder height – c) tubeless anchoring (HUMP) – d) valve
hole – e) ventilation opening – f) offset – g) central hole
diameter – h) connection hole centre to centre distance
i) keying diameter – j) rim channel.
III - Air chamber (tube type tyres). The air chamber is
a closed ring-like rubber structure with a valve, which
contains pressurised air.
Valve. The valve is a mechanical device to inflate/deflate
the tyre and maintain air pressure inside the air chamber
(or tyre in the case of tubeless tyres). It consists of three
elements: the valve closing cap (a) (to protect the internal
mechanism from dust and guarantee air tightness), an
internal mechanism (b) and the base (c) (the outer lining).
Tubeless Inflator. Inflation system that makes easier the
inflation of tubeless tyres.
Bead insertion. Operation which takes place during
inflation and ensures perfect centring between the bead
and the rim edge.
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a
c
b
d
e
g h
f
j
Operator manual
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