Energy Efficiency of the Vulcanization Process of a Bicycle Tyre

The production of tyres is one of the most energy consuming manufacturing activities in the rubber sector. In the production cycle of a tyre, the curing operation has the maximum energy loss. This is mostly due to the extensive use of steam as a source of heat and pressure in the vulcanization process. To the author's knowledge, no scientific work is available in the literature where the energy efficiency of a tyre vulcanization press is estimated by means of a comprehensive model of all main components, including the moulds, the press with its heated plates, the bladder and, of course, the tyre. The present work aims at filling this gap. First, the press used for developing the model is described, along with its components and its typical product, a bicycle tyre. The instruments used for measuring flow rates, temperatures and pressures are also listed. Then, a numerical model is presented, that predicts the energy transfers occurring in the vulcanization press during a full process cycle. The numerical model, developed with the software Simcenter Amesim 2021.1, has been validated by means of measurements taken at the press. The results indicate that the amount of energy which is actually consumed by the tyre for its reticulation process amounts to less than 1% of the total energy expenditure. The paper demonstrates that the tyre industry is in urgent need of an electrification conversion of the traditional steam-based processes.

Automated summary

The production of tyres is a highly energy-consuming activity in the rubber sector, with curing operations accounting for the largest energy loss due to the extensive use of steam. This study fills the gap in the literature by estimating the energy efficiency of a tyre vulcanization press using a comprehensive model. The model predicts energy transfers in the press during a full process cycle and shows that the actual energy consumed by the tyre for its reticulation process is less than 1% of the total energy expenditure. The paper highlights the urgent need for electrification conversion in the traditional steam-based processes of the tyre industry.