Plastics fuel tanks for automobiles not yet preferred in Asia

Plastics fuel tanks in automobiles have been in existence for over three decades. The first plastic fuel tank was installed in the 1969 Porche model. In fact, today more than 90% of European cars and 70% of North American cars are fitted with plastics fuel tanks. Yet! The Asian car manufacturers seem to remain aloof from the plastics fuel tank, evident in the fact that plastics fuel tanks are fitted in only 10-15% of Asian cars.
What factors lead to the non preference of plastics fuel tanks in Asia?

The predominant presence of small cars in Asia, having lower weights as compared to the European and North American cars could be a major reason. The major driving force; weight saving; does not exist in Asian cars. Or is it that labour required to assemble metal tanks is cheaper in Asia and therefore savings in the form of labour does not provide enough incentive for the changeover? Or the minimum economic size restricts its usage in Asia? The mould of fuel tanks is quite expensive and needs orders of larger size to amortize its cost.
All these factors contribute to the fact that plastics fuel tanks for automobiles are not yet preferred in Asia.
Will this trend reverse in the near future?

Plastics fuel tanks made from high molecular weight HDPE along with co-extruded EVOH are very widely used in European and North American cars. High molecular weight of HDPE provides toughness and more uniform thickness distribution on account of higher melt strength. EVOH provides the required resistance to fuel vapour to prevent loss of fuel. The plastics fuel tanks obviously provide corrosion resistance, the only alternative to such corrosion resistance being stainless steel. Most of the Asian cars use metal sheets which are not effective in corrosion resistance.

The fuel tank is generally manufactured from extrusion blow moulding. However, it can also be manufactured by thermoforming process. PE fuel tank manufactured by thermoforming, though not yet fully established, is being used by one of the big Australian cars.

The plastics fuel tanks have excellent resistance to loss of fuel vapour and meet all the present emission norms. However, the new emission law to be introduced in 2005 in California would demand extensive development work, particularly from the connection / joints that are the most prone to leakage. This law will demand less than 0.054 grams of fuel loss/day. Will this new law reverse the trend in favour of stainless steel tanks in North America? Or will the plastic moulders, along with HDPE suppliers like Basell and Solvay rise to the occasion with newer developments?

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