WASHINGTON, Jan 27 (Reuters) - A U.S. trade panel gave unanimous final approval on Tuesday to hefty import duties on Chinese-made bed springs.

The U.S. International Trade Commission voted 6-0 that Chinese innersprings being sold in the United States at "less than fair value" have hurt U.S. producers.

U.S. springs manufacturer Leggett & Platt filed a petition in late 2007 asking for import protection.

The ITC ruled domestic producers have been injured by the unfairly-priced Chinese springs, even though imports declined to 1.06 million pieces in 2007 from 1.54 million in 2005.

The panel vote sets the way for the Commerce Department to issue a final anti-dumping order imposing duties ranging from around 165 to 235 percent on the Chinese product.

The case is one of many trade cases that have been filed against China in recent years.

Last week, the Commerce Department gave preliminary approval to anti-dumping duties ranging up to 324.43 percent on certain tow-behind lawn groomers from China.

It also announced final duties on stainless pressure pipe from China. It set an antidumping duty of 299.16 percent on Froch Enterprise Co Ltd and a countervailing duty of 55.21 percent on all Chinese producers or exporters with the exception of Zhejiang Jiuli Hi-Tech Metals Co, which had a lesser countervailing duty of 10.53 percent.