Optimization of the warm up process of the compression moulds for the tyre manufacturing industry

Abstract

Pneumatic tyres are of major importance in the modern life. It is estimated that over one billion tyres are manufactured worldwide annually. The manufacturing process is rather power consuming one, mainly to a curing operation taking place in a press dome. The tyre compression mould warm up process is a powerful heat transfer technique. Saturated steam is fed into a press dome to directly transfer heat energy into the prismatic container through convection and conduction heat transfer.

This dissertation concerns the work done at Apollo-Dunlop tyres, the tyre compression mould warm up process was optimised to reduce the high energy cost. A heat transfer numerical analysis was carried out to investigate the steam quantity required to warm up the tyre compression mould from an ambient temperature ( ) to operational temperature ( ). Thereafter, an experimental work was performed to investigate the actual duration required to warm up the tyre compression mould to the operational temperature. This was achieved by establishing a temperature profile of the tyre compression mould during the warm up session. The numerical analysis and the experimental results were correlated to create a new warm up process with reduced steam consumption and warm up duration. The new warm up process was tested and the results are furnished in this study (see Appendix B for the performance results sheet). Apollo-Dunlop tyres (Pty) Ltd reduced a five hour tyre compression mould warm up process to a three hour process. The implementation of the proposed reduced warm up process occurred after the research work in this paper was presented to Apollo-Dunlop tyres (Pty) Ltd board members. This work was acknowledged by the company management and a new technological process has been implemented (Appendix A for the relevant documents, note: the specifications sheet show the warm-up duration as four hours, but the actual operational warm up duration is five hours). A cost saving analysis on energy usage was carried out to indicate that Apollo–Dunlop tyres will currently save approximately around about

0.64 million per year after implementing this study.