Corghi A 2030 Manual De Uso página 129

- ensure driving power,
- steer the vehicle,
- aid handling and braking,
- aid vehicle suspension.
1 - The tread. It is the part in contact with the road while
the tyre is rolling. It comprises a rubber compound
and a "pattern" suitable for ensuring good resistance
to abrasion and good grip in dry and wet conditions,
as well as quiet operating conditions.
2 - Edge or bracing. It is an insert of metallic or textile
fabric, placed at the outer part of the bead; it is used
to protect the carcass plies from sliding against the rim.
3 - Casing. This is the resistant structure and comprises
one or more layers of rubber plies. The way the plies
comprising the casing are arranged give the structure
its name. The following structures are possible:
Conventional: the plies are inclined and arranged so
that the strands comprising a ply overlap with those
of the adjacent ply. The tread, which is the part of the
tyre in contact with the ground, is part of the sidewalls
and so during rolling, sidewall flexure is transmitted
to the tread.
Radial: the casing consists of one or more plies with
the cords in radial direction.
A radial casing in itself is quite unstable. To make it
stable and prevent incorrect tread movement in the
area of contact with the ground, the casing and the
shim under the tread are reinforced with an annular
structure, usually called a belt. The tread and sidewall
work with different, independent rigidities, so during
rolling, sidewall flexure is not transmitted to the tread.
4 - Side ring. This is a metal ring comprising several
steel strands. The casing plies are secured to the
side ring.
5 - Belt. This is a non-flexible circumferential structure
comprising cross-plies at very low angles, positioned
below the tread, with the aim to stabilise the casing
in the footprint area.
6 - Centring band. This is a small mark that indicates
the circumference of the upper part of the bead and
is used as a reference to control correct tyre centring
on the rim after mounting.
A 2030 - A 2025 - A 2022 - A 2018 - A 224 A - A 224 Operator's manual
1
12
9
3
7
14
13
8
5
EN
11
6
129