Provided is a tire with excellent durability. The tire includes a tread rubber and a carcass containing a hybrid cord of at least one polyamide fiber yarn and at least one polyester fiber yarn, the hybrid cord having a twist coefficient K3 of 1800 or more and 2600 or less in final twisting as determined by R3?(D3).sup.1/2 where R3 is a final twist number [times/10 cm] of the hybrid cord and D3 is a total fineness [dtex] of the hybrid cord, the twist coefficient K3 and a thickness L [mm] of the tread rubber giving a product (K3?L) of 15000 or more.

The present invention provides a pneumatic tire by which workability when molding a tire and tire durability performance can be enhanced without increasing tire weight when providing a reinforcing layer formed by aligning a plurality of monofilament steel wires and embedding this plurality of monofilament steel wires in rubber. The pneumatic tire of the present invention includes a reinforcing layer formed by aligning a plurality of monofilament steel wires and embedding said monofilament steel wires in rubber. Each of the monofilament steel wires is provided with twisting around an axis thereof, and a wire surface twisting angle with respect to an axial direction of the monofilament steel wires is not less than 1.

A method for manufacturing a straight steel monofilament for the reinforcement of belt ply of a pneumatic tyre, where the arc-height of the straight steel monofilament is less than 30 mm. The steel monofilament is plastically deformed by a twisting along the axis of the steel monofilament on a double-twist apparatus. The plastic twist deformation eliminates the surface stress difference on the steel monofilament and provides a straight steel monofilament for belt ply reinforcement. This provides a simple solution with existing apparatus to manufacture straight steel monofilament suitable for tire reinforcement with high speed for mass production.

The various embodiments relate to pneumatic tires including a cap ply of braided strands of yarn. Various embodiments relate to strands of yarn that are fiberglass filaments or steel. The braided strands may include a tight braid or a loose braid. Various embodiments include braids having 1 to 5 stitches per cm.

The present invention relates to a steel cord for rubber reinforcement. In the steel cord of the present invention, cobalt is contained by 0.001 ppm to 0.1 ppm within a 4 nm top-surface of the brass-plated steel wire. A method of manufacturing the steel cord includes: providing a brass-plated steel wire; mixing a cobalt compound in a wet lubricant filled in a wet drawing bath provided with a plurality of drawing dies between one pair of multi-stage drawing cones such that the concentration of the cobalt compound becomes 0.1 ppm to 100 ppm; and causing the cobalt to be contained by 0.001 ppm to 0.1 ppm within a 4 nm top-surface of the brass-plated steel wire after the brass-plated steel wire passes through a final die by causing the cobalt to be attached to a surface of the brass-plated steel wire and alloyed with a brass layer while the brass-plated steel wire is passing through the drawing cones and the drawing dies to be subjected to multi-stage drawing.

A steel wire has a microstructure that is completely ferritic, a mixture of ferrite and cementite or a mixture of ferrite and pearlite and has a weight content of carbon C such that C<0.05% and a weight content of chromium Cr such that Cr<12%. The process for drawing the wire comprises: at least one first uninterrupted series of steps of drawing the wire from a diameter D to a diameter d, at least one second uninterrupted series of steps of drawing the wire of diameter d to a diameter d, and one or more intermediate steps between the first and second uninterrupted series of steps of drawing the wire, the wire having a temperature less than or equal to 300 C. during the or each intermediate step.

A steel wire having a cross section perpendicular to a longitudinal direction having a flat shape, and an outer shape of the cross section including a pair of linear parts opposing each other, and a pair of curved parts opposing each other and connecting the linear parts. The curved part includes a pair of first regions located at positions near the linear parts, and a second region located at a position between the pair of first regions, a radius of curvature, R.sub.1 of the first region is greater than or equal to 0.05 mm but less than 0.15 mm, and a radius of curvature, R.sub.2 of the second region is greater than or equal to 0.13 mm but less than or equal to 0.2 mm, and an angle between the linear part and the curved part is greater than or equal to 165 degrees.

A method of manufacturing a tire, a forming system for the tire, and the tire are provided. A preceding carcass cord from one feeding unit is used to form a carcass layer while being fed to a forming drum, and a leading edge portion of a next carcass cord is paid out from another feeding unit in advance. At a time when a predetermined length of the preceding carcass cord is fed, a splice mechanism is used to join the leading edge portion of the next carcass cord to the preceding carcass cord to make the leading edge portion of the next carcass cord continuous with the preceding carcass cord. Then, with the next carcass cord fed to the forming drum, formation of the carcass layer is continued to complete the carcass layer.

A device, which converts a reinforcing strip from being flat to being undulating, includes a transporter that guides fingers along a closed circuit, with the fingers being able to bear against a first face of the strip; a support plate that rotates about a plate axis and that supports rollers having axes parallel to the plate axis, with the rollers being able to bear against a second face of the strip; and a synchronizer that synchronizes a rotation of the support plate and a forward motion of the transporter. The closed circuit has an intersecting portion at which the synchronizer allows the fingers and the rollers to move rotationally in a common plane perpendicular to the plate axis, with the fingers and the rollers being interposed at the intersecting portion so as to cause the strip to have undulating waves that extend in the common plane.

The invention provides a steel cord with a construction of n1, n is the number of the steel filaments of the steel cord, the steel cord has an elongation at 2.5N-50N of less than 1.2% and a twist pitch of greater than 16 mm, each of the steel filaments has a form of helical wave with a wave length L expressed in mm and a wave height H expressed in mm when being unravelled from said steel cord, L is greater than 16 mm, each of the steel filaments has a space volume Vs satisfying that, Vs=LH.sup.2/4, and Vs>20 mm.sup.3. The invention steel cord is beneficial for the stress distribution.