Italian-based tyre retreader Marangoni’s latest product development in the OTR tyre segment represents a new retread solution for Kiruna slag pot carriers. According to Ayhan Haliloglou, OTR tyre Area Manager at Marangoni, Valtasiirto, a Finnish company specialising in delivering comprehensive solutions for industrial indoor and outdoor logistics requested for design specifications that included traction and cut/tear resistance features, required for the use in the mining industry.
Marangoni introduced “new premium tyres” with a custom casing, higher load capacity and a completely new tread design.
In producing the casing model, Marangoni first proposed a rigorous casing inspection regime for the tyres to be equipped on the Kiruna utility vehicles; Haliloglou also said that Marangoni had not retreaded a tyre size of 29.5R29 before, so its operators extensively checked the different parts of the tyres to ensure their quality and casing integrity prior to the retreading process.
Haliloglou added: “The OTR tyre is rebuilt from the casing on as if it was a new tyre. The casing is mounted on the building machine and spins, while an extruder arm applies three different layers of compound – base, intermediate and tread – evenly from shoulder to shoulder.”
During the inspection/measurement phase of the casing, when it became apparent that this specific type of casing could not be processed in a conventional hot-cure mould, Marangoni opted to cure the tyre in their autoclave. The different curing facilities, namely Marangoni’s Recaflex system, that Marangoni has in its Rovereto factory enables the company to retread almost any OTR tyre available. Finally, a shearography machine was used for a detailed visual inspection of the inner structure of the tyre, to identify defects and imperfections. Marangoni is one of the few European retreaders to use this method.
The tyres have since been shipped back to Finland where the MTXL retreads are in operation and are being closely monitored by Lujakumi’s technical specialists. As a distributor, Finnish-headquartered Lujakumi has been using Marangoni’s Ringtread System for the retreading of truck and bus tyres. As of 2018, Lujakumi has added Marangoni OTR retreads to their commercial offer.