The present invention relates to a self-supporting tire for vehicle wheels comprising a carcass structure comprising at least one carcass ply having a plurality of hybrid reinforcing cords (10) each comprising at least two strands (20) twisted to each other with a predetermined stranding pitch (P), wherein each of said at least two strands (20) comprises at least one monofilament textile thread (21) at least partially embedded in the filaments (22a) of at least one multifilament textile yarn (22) and a pair of sidewall reinforcement inserts (113), where at least one of said sidewall reinforcement inserts comprises a vulcanised elastomeric compound which has a dynamic shear modulus value G equal to or less than 1.25 MPa measured at 70° C., 10 Hz, 9% deformation according to the RPA method reported in the present description.

Provided is a heavy-duty pneumatic tire in which not only occurrence of a damage of CBU but also occurrence of pulling-out of a carcass ply can be inhibited, and which has excellent durability. In the tire, beads each include a cover enclosing at least a part of a core. The cover is located, between the core and the carcass ply, in a portion at which the carcass ply encloses the core. The cover is composed of one cover ply including a large number of aligned cover cords and a cover topping rubber covering the cover cords. A ratio of a distance between the cover cords to an outer diameter of a carcass cord is not lower than 0.35 and not higher than 0.85. A difference between a hardness of the cover topping rubber and a hardness of a carcass topping rubber is not less than −5 and not greater than 5.

The present invention relates to a tire cord having excellent durability while being thin in thickness, a manufacturing method thereof and a tire comprising the same.

A tire for an agricultural vehicle (1), and in particular the carcass reinforcement (4) thereof, for a tire running at low pressure on loose ground, is to reduce the compaction of the ground and to increase the traction capability by reducing the structural stiffness of the tire. According to the invention, the carcass reinforcement (4) is made up of a single carcass layer (41) having a mean thickness E at most equal to 2 mm and a breaking strength Fr, expressed in daN/cm, that satisfies the relationship:

Fr>=Fs=(Cs*Pmax*10.sup.−3)*((R.sup.2−((R+Rj)/2).sup.2)/2)/Rj, with Fs: reference threshold strength (in daN/cm) Cs: safety factor at least equal to 1, Pmax: recommended maximum inflation pressure (in kPa), R=D/2: outside radius of the tire (in mm), Rj=Dj/2: nominal radius of the rim (in mm).

A pneumatic tire comprises a carcass ply extending between bead portions through a tread portion and sidewall portions, and turned up around a bead core from the inside to the outside of the tire in each of the bead portions, so as to form a pair of turnup portions and a main portion therebetween. In each the bead portion, a first apex rubber and a second apex rubber are disposed. The first apex rubber is disposed between the turnup portion and the main portion. The second apex rubber is disposed axially outside the turnup portion. A complex elastic modulus b of the second apex rubber is larger than that of the first apex rubber. The cross-sectional width Wt in mm of the tire and the outer diameter Dt in mm of the tire satisfy the following conditions Dt=<59.078×Wt.sup.0.498 and Dt>=59.078×Wt.sup.0.460.

In a pneumatic tire, at least one carcass layer mounted between a pair of bead portions is formed from a carcass cord formed of an organic fiber cord having filament bundles of organic fibers intertwined together, a fineness based on corrected mass of the carcass cord is from 4000 dtex to 8000 dtex, an intermediate elongation of the carcass cord at a sidewall portion under 1.0 cN/dtex load is from 3.3% to 4.2%, and a ratio G/R of an interlayer rubber gauge G between a body portion and a folded back portion to a cord diameter R of the carcass cord, at a contact region where the body portion and the folded back portion are in contact in the carcass layer, is from 0.50 to 0.60.

A pneumatic tire includes a tread portion, sidewall portions, a pair of bead portions embedded with bead cores, and a carcass. The carcass includes a turned up ply including a main body portion extending between the bead cores, and a pair of turned up portions turned up around the bead cores from axially inside to outside. Each bead portion is provided with an inner apex rubber extending radially outward from the bead core between the main body portion and the turned up portion and an outer apex rubber arranged axially outside the turned up portion. The inner apex rubber has a radial height of from 18 to 30 mm. A buttress thickness D, a maximum width thickness E, and a bead thickness F satisfy Expressions (1) to (4):

E≥4.5 mm  (1)

F≥9.0 mm  (2)

E/D=0.6 to 0.9  (3)

F/E=1.7 to 2.2  (4).

In a pneumatic tire, at least one carcass layer mounted between a pair of bead portions is formed from a carcass cord formed of an organic fiber cord having filament bundles of organic fibers intertwined together, a fineness based on corrected mass of the carcass cord is from 4000 dtex to 8000 dtex, an intermediate elongation of the carcass cord at a sidewall portion under 1.0 cN/dtex load is from 3.3% to 4.2%, and a ratio G/R of an interlayer rubber gauge G between a body portion and a folded back portion to a cord diameter R of the carcass cord, at a contact region where the body portion and the folded back portion are in contact in the carcass layer, is from 0.50 to 0.60.

A tire can include a pair of beads, a carcass, an inner liner, and an insulation located between the carcass and the inner liner. The carcass can include one carcass ply. The carcass ply can include a plurality of carcass cords and a topping rubber. Each carcass cord can have a total fineness of not less than 6000 dtex and not greater than 9000 dtex. The insulation can be located between first and second beads. A ratio (ta/td) of a thickness to of the topping rubber located between the insulation and the carcass cords to a thickness td of the insulation can be not less than 0.2 and not greater than 0.6.

A tire for a civil engineering vehicle the endurance of which has been improved by the addition of an anti-creep layer (30) with a thickness E2 interposed between the airtight inner layer (20), with a thickness E1, and the reinforcer coating layer (46) of the carcass reinforcement (40), with a thickness E3. The thicknesses E1, E2 and E3, being measured in millimetres in a shoulder region forming the transition between the crown and each sidewall of the tire, satisfy the following equations: 2≤E1≤4; 6≤E2+E3 and E1/E2≥0.6. In addition, the viscoelastic loss P60 of the elastomeric mixture M2 of the anti-creep layer (30) is at most equal to 20%.