Procedure of workmanship
The purpose of initial inspection is to verify that a casing is acceptable for retreading, using a thorough inspection of each tyre, inside and outside. Identify casing injuries and determine if repairable. The following step is inflating the tyre to almost double of the pressure on the road and this allows to detect pick-out deformities, damages to the structure etc... These two selections allow us to proceed with the following steps eliminating the frameworks that have been discarded wich is about 30% and for the selected tyres to pass on to the following step.
This step involves removing by rubber turning, the worn tread of the tyre, and to give them due to sophisticated machinery the proper shape and dimension for the next process and to render the adhesion surface clean and rough. The tread scraping allows to eliminate the frameworks that reveal separated layers in the surface structure, that means further selection (up to 5% discharge). From may 2014 we have introduced the new computer controlled buffing machine RAS 45.
In this phase a strip of rubber is applied on tire, a
computerized machinery working with dimensions, thickness and profiles of the
tyres stored in memory makes this operation precise and versatile, allowing to
compensate differences among the frameworks. On every tyre the right quantity
and thickness of material is applied in order to improve the following work.
This procedure allows to avoid rubber joints favouring the final tyre balancing.
This operation allows to identify and compensate the unbalances on casings to be retreaded.
Is a true chemical transformation that allow to permanently join rubber to framework, this takes place inside some moulds inserted in presses working at 150° C and 15 Bar of pressure in predetermined times and it allows to engrave the final profile on the tyre, restoring the shape that all knows. Inflating nitrogen during the cooking allows the respect of pressure and vulcanization curves, to advantage the uniformity of worn and own long road life. This phase represents an ulterior test of validity and resistance of the work, that finally it will begin a new life on the road.
After varnishing that makes it look like a new tire two verifications make the final quality control: first an accurate inside control looking for damages, separations or bad reparations, then pressure control that is made by skilled staff and this allows to pick out the possible fault production. This is a selection procedure that allows to send to final use only the perfect product. Finally a finishing touch that removes each possible rubber dribbles.