A process for manufacturing a reinforcing structure of a tire for vehicle wheels, is carried out on a toroidal support including an outer surface, by means of at least one laying element, which can be oriented in space in a controlled way; the laying element including a laying surface adapted to act on a portion of a rubberized strip-like element for laying the same on the outer surface of the toroidal support. The reinforcing structure includes at least a first and a second radially superimposed reinforcing layers, each including a plurality of strip-like elements; each reinforcing layer having a circumferential extension about a rotation axis of the tire and comprising thread-like reinforcing elements, arranged parallel to one another. The layers are arranged so that the reinforcing thread-like elements of the first reinforcing layer are oriented obliquely with respect to the equatorial plane of the tire, and that the reinforcing thread-like elements of the second reinforcing layer also have an oblique orientation, crossed with respect to the thread-like elements of the first layer.

An application device for applying a conductive insert on a tyre being processed. The application device includes a supply device for supplying a conductive liquid elastomeric compound, and an applicator having a movable surface for being operatively coupled with the supply device and receiving the conductive liquid elastomeric compound. The movable surface is for being placed in contact with a rotating tyre being processed and for applying the conductive liquid elastomeric compound on at least one coil of axially adjacent and/or partially superimposed coils. The applicator generates depressions in the tyre in a pattern defined by elements in relief and fills the depressions in the tyre with the conductive liquid elastomeric compound to covering the elements as the depressions in the tyre are generated.