Temperature measurement and control within moulded rubber during vulcanization process

Controlling the vulcanization of thick moulded rubber parts is an important industrial challenge. The vulcanization field of moulded rubber parts, indeed, is dependent upon the temperature history undergone by any rubber points during moulding process. The geometrical sophistication of many industrial parts causes inhomogeneity of heat transfers within the mould cavity during the moulding cycle. Vulcanization field assessment requires to develop a heat transfer model, which would be coupled to the rubber chemical history within the mould. With this aim in view, a simulation tool is proposed here. In order to validate the model, a temperature-controlled moulding device is developed and described in this paper. The accuracy of the thermal control and the supervision of heat transfers it allows is specially underlined. Mould temperature history checking is carried out using an original measuring device recording temperatures directly within the moulded parts. The control of heat transfers achieved with the moulding equipment presented here is verified with experimental measurements. These results also confirm the validity of the heat transfer model. Digital modelling here has made it possible to predict successfully the vulcanization front (dividing surface between unvulcanized and vulcanized materials) progress in various moulding configurations.