Quake-hit Riken says unclear when output to resume

TOKYO, July 18 (Reuters) - Riken Corp. 6462.T, a major Japanese manufacturer of piston rings, said on Wednesday it was unclear when it could resume production at its quake-hit factories -- a development that may disrupt supplies to Japan's auto makers.

The company has two piston ring plants and nine affiliated plants in Kashiwazaki, the city worst hit by the quake, in northwestern Japan.

Riken says it commands half of the domestic market for piston rings and around 70 percent of the market for seal rings that prevent oil leaks in automatic transmissions and continuously variable transmissions.

The company said it planned to spend the next few days putting equipment in proper position.

After that it would continue to check the precision of the equipment, make test runs and check for quality before beginning full-fledged production. Gas and water supplies were still cut off, it added.

((Reporting by Edwina Gibbs, editing by Mike Miller; Reuters messaging:; Email:; +81 3 3432-8720)) Keywords: JAPAN QUAKE

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