Bridgestone Maximising Raw Materials Efficiency

During 2000 and early 2001 the BLIC (Bureau de Liaison des Industries du Caoutchouc), predecessor to the European Tyre and Rubber Manufacturers’ Association, conducted a full Life Cycle Assessment study (LCA) of a representative European 195/65 R15 passenger car tyre, using both carbon black and silica based versions of the H rated summer tyre in the study. Bridgestone, as a member of the Technical Working Group, played an active role in the study.

While, at 84 per cent, the ‘use’ phase of a tyre’s life cycle was identified by the LCA as making the largest contribution to the environmental load of a car tyre, the impact of raw materials, which accounts for 10 per cent, is the second largest factor. Keeping this in mind, Bridgestone Europe comments in its latest Environmental Commitment and Performance report, published November 2008, that the choice of ingredients used is very important, including the promotion of an environmental oriented supply chain.

The most prevalent of these ingredients, according to LCA data, is rubber, which accounts for 43 per cent of a passenger car tyre’s content (25 per cent synthetic and 18 per cent natural). Fillers, carbon black and silica, take a 28 per cent slice of the tyre raw material cake, and various chemicals and cords make up the rest (see pie chart for details).

Bridgestone selects its suppliers according to the framework of its Bridgestone Product Oriented Environmental Management System (POEMS), which organises the efforts of different functions, competencies and resources towards the goal of continuously improving the environmental performance the company’s tyres. Under this POEMS framework then, environmental criteria plays a significant role in the selection of suppliers, and their compliance with legal and other requirements through the chain is strictly verified by the company. For Bridgestone Europe this means that a supplier with ISO 14001 certification would potentially receive preferential selection through a ranking system.

Many people adhere to the saying ‘if you want a job done properly, do it yourself’, and while Bridgestone doesn’t apply this thinking in its policies, the company relies ever more so upon in-house supply capabilities for a portion of its natural and synthetic rubber, carbon black and steel cord. Bridgestone currently operates 19 raw material facilities in 10countries, not counting those belonging to major subsidiaries. The newest of these facilities is the carbon black production plant operated by Mexico Carbon Manufacturing SA DE CV, a wholly owned member of the Bridgestone Group. The 35,000 ton a year facility, the company’s third, opened in October 2008 and will supply the Bridgestone Group’s tyre plants in the Americas.

As part of its said goal to become the undisputed number one tyre and rubber company, Bridgestone reports it is working to enhance competitiveness throughout the entire supply chain. In late October the company announced the details of an agreement made with Toyo Tire & Rubber to “create increased efficiencies and generate synergistic efforts” in a number of areas. Under this arrangement with Toyo, when procuring raw materials the two companies will mutually supply materials produced in-house and maximise the utilisation of both companies’ engineering subsidiaries. Bridgestone and Toyo will also, in the medium to long-term, jointly procure raw materials and integrate raw material specifications to the greatest extent possible.

One potential source of raw materials is not heavily utilised by Bridgestone, the company states in its recent report. This is recycled content; aside from recycled zinc oxide, which accounts most of the zinc oxide used by Bridgestone in its tyres, the company comments that using a level of recycled content in its tyres has generally shows negative effects on wear and rolling resistance, and thus on fuel consumption. This occurs due to a loss of chemical reaction in the material. The tyre major adds that the limited and unstable supply of high-quality crumb rubber, and recycled materials in general, restricts the recycled content in tyres, and thus the company utilises only a small proportion of post-consumer recycled tyre material in its tyre lines.