Mondolfo Ferro AS 924 Manual De Uso página 124

is the outer 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 adding air and maintaining, controlling
and restoring air pressure is part of the chamber in
this case.
Tubeless tyres. Tubeless tyres consist of a tyre with
inner sidewall lined with a thin layer of special im-
permeable rubber, called liner. This liner helps to
maintain air pressure in the casing. This kind of tyre
must be mounted on a specific rim, to which the valve
is directly fixed.
II - Rim (Wheel). The wheel is the rigid metal part a
which connects the vehicle hub to the tyre, on a fixed
c
b
but non-permanent basis.
d
e
Rim profile. The rim profile is the form of the section
in contact with the tyre. It comprises different geo-
metric forms, which ensure: easy tyre mounting (bead
insertion in the rim well); safe driving, in terms of the
i
g h
bead anchored in its seat.
The rim section shows its various parts: a) rim width
– b) shoulder height – c) tubeless anchoring (HUMP)
– d) valve hole – e) ventilation opening – f) off set – g)
f
central hole diameter – h) attachment hole centre to
centre i) keying diameter – j) rim well.
III - Air chamber (tube type tyres). The air chamber is
j
a closed ring-like rubber structure with a valve, which
contains pressurised air.
Valve. The valve is a mechanical device to inflate/
c
a
b
deflate the tyre and maintain air pressure inside the
air chamber (or tyre in the case of tubeless tyres). It
consists of three parts: the valve closing cap (a) (to
protect the internal mechanism from dust and guar-
antee air tightness), an internal mechanism (b) and
the base (c) (the outer lining).
Tubeless Inflator. Inflation system that makes the
inflation of tubeless tyres easier.
Beading. Operation which takes place during inflation
and ensures perfect centring between the bead and
AS 924 - AS 924 A Operator's Manual
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