BEIJING, March 23 -- China, the world's biggest consumer of copper, more than doubled imports of the metal in February compared with the same month last year as the nation entered its peak demand period for the construction industry.

Imports of refined copper and alloys rose to 152,651 metric tons, 167 percent more than a year earlier, according to data issued by the Beijing-based Customs office yesterday. That's the highest import level since May 2005, according to data by Bloomberg News.

The price of copper, used in plumbing materials and wires, has gained five percent so far this year amid speculation that Chinese imports would pick up on seasonal demand. The country drew on its stockpiles after prices rose to a record 8,800 U.S. dollars a ton on May 11, and last year's imports slumped by almost a third.

"Chinese demand for imports is showing no sign of flagging," said Li Ling, a trader at Star Futures Co. in Shanghai. "As it's entering a peak consumption period, some processors increased purchases."

Copper prices have rallied every year since 2002 because of falling stockpiles, strong Chinese demand and supply disruptions from major producers such as Chile.

On the London Metal Exchange, copper for delivery in three months rose 136 dollars, or 2.1 percent, to 6,745 U.S. dollars a ton, at 6:08pm Shanghai time yesterday. Copper for delivery in June rose 0.7 percent to settle at 61,000 yuan (7,895 dollars) a ton on the Shanghai Futures Exchange.

China's apparent consumption of copper was 356,763 tons in February, according to Bloomberg calculations derived by combining production and imports, minus exports and reported stockpile increases.

China's demand for copper rose to 387,000 tons in January from 288,000 tons a year earlier, the World Bureau of Metal Statistics said on Wednesday.

The country's output of copper fell 4.8 percent to 220,000 tons in February, according to data from the National Bureau of Statistics issued in a statement on March 16.

Refined copper production has been limited by shortages of copper concentrates, the raw material for the refined metal. Imports of copper concentrates rose 35 percent to 392,366 tons in February, the customs data showed.

In February, copper stockpiles monitored by the Shanghai Futures Exchange rose 16,888 tons, or 70 percent, to 40,886 tons. Stockpiles of the rival lightweight metal aluminum rose 63,334 tons, or 217 percent, to 92,927 tons.