Process for building an additional component within a vulcanised tyre comprising: a) arranging a vulcanised tyre having an external surface and an internal surface arranged around a rotation axis (X) of the vulcanised tyre itself and grasping said vulcanised tyre by means of a grip device , b) executing a preliminary scan of at least one deposition portion of the internal surface of said vulcanised tyre , c) generating a mathematical model of said at least one deposition portion on the basis of said preliminary scan, d) executing a deposition process for depositing at least one layer of said additional component directly on said at least one deposition portion, wherein said deposition process comprises: d1) positioning, at a starting position and at a relative distance from said at least one deposition portion, a dispensing nozzle configured for dispensing a continuous elongated element (E), d2) activating a continuous dispensing of the continuous elongated element (E) through said dispensing nozzle , d3) generating a relative deposition motion between said dispensing nozzle and said vulcanised tyre , starting from said starting position and simultaneously with said continuous dispensing, following a trajectory according to said mathematical model adapted to make a spiral deposition of the continuous elongated element (E) on said at least one deposition portion up to the building of said layer , e) controlling said deposition process by means of the adjusting of at least one deposition parameter as a function of the mathematical model of said at least one deposition portion. a) arranging a vulcanised tyre having an external surface and an internal surface arranged around a rotation axis (X) of the vulcanised tyre itself and grasping said vulcanised tyre by means of a grip device , b) executing a preliminary scan of at least one deposition portion of the internal surface of said vulcanised tyre , c) generating a mathematical model of said at least one deposition portion on the basis of said preliminary scan, d) executing a deposition process for depositing at least one layer of said additional component directly on said at least one deposition portion, wherein said deposition process comprises: d1) positioning, at a starting position and at a relative distance from said at least one deposition portion, a dispensing nozzle configured for dispensing a continuous elongated element (E), d2) activating a continuous dispensing of the continuous elongated element (E) through said dispensing nozzle , d3) generating a relative deposition motion between said dispensing nozzle and said vulcanised tyre , starting from said starting position and simultaneously with said continuous dispensing, following a trajectory according to said mathematical model adapted to make a spiral deposition of the continuous elongated element (E) on said at least one deposition portion up to the building of said layer , d1) positioning, at a starting position and at a relative distance from said at least one deposition portion, a dispensing nozzle configured for dispensing a continuous elongated element (E), d2) activating a continuous dispensing of the continuous elongated element (E) through said dispensing nozzle , d3) generating a relative deposition motion between said dispensing nozzle and said vulcanised tyre , starting from said starting position and simultaneously with said continuous dispensing, following a trajectory according to said mathematical model adapted to make a spiral deposition of the continuous elongated element (E) on said at least one deposition portion up to the building of said layer , e) controlling said deposition process by means of the adjusting of at least one deposition parameter as a function of the mathematical model of said at least one deposition portion. <EOS>